Merge remote-tracking branch 'origin/master'

66 files changed, 1688 insertions, 417 deletions

diff --git a/src/main/java/org/traccar/BaseHttpProtocolDecoder.java b/src/main/java/org/traccar/BaseHttpProtocolDecoder.java
index 57a68acac..b762be12c 100644
--- a/src/main/java/org/traccar/BaseHttpProtocolDecoder.java
+++ b/src/main/java/org/traccar/BaseHttpProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 - 2018 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,6 +15,8 @@
  */
 package org.traccar;
 
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
 import io.netty.channel.Channel;
 import io.netty.handler.codec.http.DefaultFullHttpResponse;
 import io.netty.handler.codec.http.HttpHeaderNames;
@@ -29,9 +31,16 @@ public abstract class BaseHttpProtocolDecoder extends BaseProtocolDecoder {
     }
 
     public void sendResponse(Channel channel, HttpResponseStatus status) {
+        sendResponse(channel, status, null);
+    }
+
+    public void sendResponse(Channel channel, HttpResponseStatus status, ByteBuf buf) {
         if (channel != null) {
-            HttpResponse response = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, status);
-            response.headers().add(HttpHeaderNames.CONTENT_LENGTH, 0);
+            if (buf == null) {
+                buf = Unpooled.buffer(0);
+            }
+            HttpResponse response = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, status, buf);
+            response.headers().add(HttpHeaderNames.CONTENT_LENGTH, buf.readableBytes());
             channel.writeAndFlush(new NetworkMessage(response, channel.remoteAddress()));
         }
     }
diff --git a/src/main/java/org/traccar/BaseProtocol.java b/src/main/java/org/traccar/BaseProtocol.java
index c0fd1e27f..bd3391822 100644
--- a/src/main/java/org/traccar/BaseProtocol.java
+++ b/src/main/java/org/traccar/BaseProtocol.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 - 2018 Anton Tananaev (anton@traccar.org)
+ * Copyright 2015 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,12 +15,14 @@
  */
 package org.traccar;
 
+import io.netty.buffer.ByteBuf;
 import io.netty.buffer.Unpooled;
+import io.netty.channel.Channel;
 import io.netty.handler.codec.string.StringEncoder;
-import org.traccar.database.ActiveDevice;
 import org.traccar.helper.DataConverter;
 import org.traccar.model.Command;
 
+import java.net.SocketAddress;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.HashSet;
@@ -68,11 +70,6 @@ public abstract class BaseProtocol implements Protocol {
         supportedTextCommands.addAll(Arrays.asList(commands));
     }
 
-    public void setSupportedCommands(String... commands) {
-        supportedDataCommands.addAll(Arrays.asList(commands));
-        supportedTextCommands.addAll(Arrays.asList(commands));
-    }
-
     @Override
     public Collection<String> getSupportedDataCommands() {
         Set<String> commands = new HashSet<>(supportedDataCommands);
@@ -88,15 +85,16 @@ public abstract class BaseProtocol implements Protocol {
     }
 
     @Override
-    public void sendDataCommand(ActiveDevice activeDevice, Command command) {
+    public void sendDataCommand(Channel channel, SocketAddress remoteAddress, Command command) {
         if (supportedDataCommands.contains(command.getType())) {
-            activeDevice.write(command);
+            channel.writeAndFlush(new NetworkMessage(command, remoteAddress));
         } else if (command.getType().equals(Command.TYPE_CUSTOM)) {
             String data = command.getString(Command.KEY_DATA);
-            if (BasePipelineFactory.getHandler(activeDevice.getChannel().pipeline(), StringEncoder.class) != null) {
-                activeDevice.write(data);
+            if (BasePipelineFactory.getHandler(channel.pipeline(), StringEncoder.class) != null) {
+                channel.writeAndFlush(new NetworkMessage(data, remoteAddress));
             } else {
-                activeDevice.write(Unpooled.wrappedBuffer(DataConverter.parseHex(data)));
+                ByteBuf buf = Unpooled.wrappedBuffer(DataConverter.parseHex(data));
+                channel.writeAndFlush(new NetworkMessage(buf, remoteAddress));
             }
         } else {
             throw new RuntimeException("Command " + command.getType() + " is not supported in protocol " + getName());
diff --git a/src/main/java/org/traccar/BaseProtocolDecoder.java b/src/main/java/org/traccar/BaseProtocolDecoder.java
index e6e02c2d6..8981fe4c8 100644
--- a/src/main/java/org/traccar/BaseProtocolDecoder.java
+++ b/src/main/java/org/traccar/BaseProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2012 - 2018 Anton Tananaev (anton@traccar.org)
+ * Copyright 2012 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,10 +21,12 @@ import io.netty.handler.codec.http.HttpRequestDecoder;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.traccar.config.Config;
+import org.traccar.database.CommandsManager;
 import org.traccar.database.ConnectionManager;
 import org.traccar.database.IdentityManager;
 import org.traccar.database.StatisticsManager;
 import org.traccar.helper.UnitsConverter;
+import org.traccar.model.Command;
 import org.traccar.model.Device;
 import org.traccar.model.Position;
 
@@ -227,20 +229,32 @@ public abstract class BaseProtocolDecoder extends ExtendedObjectDecoder {
             if (decodedMessage instanceof Position) {
                 position = (Position) decodedMessage;
             } else if (decodedMessage instanceof Collection) {
-                Collection positions = (Collection) decodedMessage;
+                Collection<Position> positions = (Collection) decodedMessage;
                 if (!positions.isEmpty()) {
-                    position = (Position) positions.iterator().next();
+                    position = positions.iterator().next();
                 }
             }
         }
+        long deviceId = 0;
         if (position != null) {
-            connectionManager.updateDevice(
-                    position.getDeviceId(), Device.STATUS_ONLINE, new Date());
+            deviceId = position.getDeviceId();
         } else {
             DeviceSession deviceSession = getDeviceSession(channel, remoteAddress);
             if (deviceSession != null) {
-                connectionManager.updateDevice(
-                        deviceSession.getDeviceId(), Device.STATUS_ONLINE, new Date());
+                deviceId = deviceSession.getDeviceId();
+            }
+        }
+        if (deviceId > 0) {
+            connectionManager.updateDevice(deviceId, Device.STATUS_ONLINE, new Date());
+        }
+        sendQueuedCommands(channel, remoteAddress, deviceId);
+    }
+
+    protected void sendQueuedCommands(Channel channel, SocketAddress remoteAddress, long deviceId) {
+        CommandsManager commandsManager = Context.getCommandsManager();
+        if (commandsManager != null) {
+            for (Command command : commandsManager.readQueuedCommands(deviceId)) {
+                protocol.sendDataCommand(channel, remoteAddress, command);
             }
         }
     }
diff --git a/src/main/java/org/traccar/Main.java b/src/main/java/org/traccar/Main.java
index 6ebd1d399..47d6e91df 100644
--- a/src/main/java/org/traccar/Main.java
+++ b/src/main/java/org/traccar/Main.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2012 - 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2012 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,6 +19,7 @@ import com.google.inject.Guice;
 import com.google.inject.Injector;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.traccar.api.HealthCheckService;
 
 import java.lang.management.ManagementFactory;
 import java.lang.management.MemoryMXBean;
@@ -105,6 +106,27 @@ public final class Main {
         }
     }
 
+    private static void scheduleHealthCheck() {
+        HealthCheckService service = new HealthCheckService();
+        if (service.isEnabled()) {
+            new Timer().scheduleAtFixedRate(
+                    service.createTask(), service.getPeriod(), service.getPeriod());
+        }
+    }
+
+    private static void scheduleDatabaseCleanup() {
+        new Timer().scheduleAtFixedRate(new TimerTask() {
+            @Override
+            public void run() {
+                try {
+                    Context.getDataManager().clearHistory();
+                } catch (SQLException error) {
+                    LOGGER.warn("Clear history error", error);
+                }
+            }
+        }, 0, CLEAN_PERIOD);
+    }
+
     public static void run(String configFile) {
         try {
             Context.init(configFile);
@@ -118,35 +140,19 @@ public final class Main {
                 Context.getWebServer().start();
             }
 
-            new Timer().scheduleAtFixedRate(new TimerTask() {
-                @Override
-                public void run() {
-                    try {
-                        Context.getDataManager().clearHistory();
-                    } catch (SQLException error) {
-                        LOGGER.warn("Clear history error", error);
-                    }
-                }
-            }, 0, CLEAN_PERIOD);
+            scheduleHealthCheck();
+            scheduleDatabaseCleanup();
 
-            Thread.setDefaultUncaughtExceptionHandler(new Thread.UncaughtExceptionHandler() {
-                @Override
-                public void uncaughtException(Thread t, Throwable e) {
-                    LOGGER.error("Thread exception", e);
-                }
-            });
+            Thread.setDefaultUncaughtExceptionHandler((t, e) -> LOGGER.error("Thread exception", e));
 
-            Runtime.getRuntime().addShutdownHook(new Thread() {
-                @Override
-                public void run() {
-                    LOGGER.info("Shutting down server...");
+            Runtime.getRuntime().addShutdownHook(new Thread(() -> {
+                LOGGER.info("Shutting down server...");
 
-                    if (Context.getWebServer() != null) {
-                        Context.getWebServer().stop();
-                    }
-                    Context.getServerManager().stop();
+                if (Context.getWebServer() != null) {
+                    Context.getWebServer().stop();
                 }
-            });
+                Context.getServerManager().stop();
+            }));
         } catch (Exception e) {
             LOGGER.error("Main method error", e);
             throw new RuntimeException(e);
diff --git a/src/main/java/org/traccar/MainModule.java b/src/main/java/org/traccar/MainModule.java
index 0957d9fe3..c3c0182d7 100644
--- a/src/main/java/org/traccar/MainModule.java
+++ b/src/main/java/org/traccar/MainModule.java
@@ -73,6 +73,7 @@ import org.traccar.reports.model.TripsConfig;
 
 import javax.annotation.Nullable;
 import javax.ws.rs.client.Client;
+import io.netty.util.Timer;
 
 public class MainModule extends AbstractModule {
 
@@ -375,6 +376,12 @@ public class MainModule extends AbstractModule {
         return new DriverEventHandler(identityManager);
     }
 
+    @Singleton
+    @Provides
+    public static Timer provideTimer() {
+        return GlobalTimer.getTimer();
+    }
+
     @Override
     protected void configure() {
         binder().requireExplicitBindings();
diff --git a/src/main/java/org/traccar/Protocol.java b/src/main/java/org/traccar/Protocol.java
index 3b66f2598..aea69b353 100644
--- a/src/main/java/org/traccar/Protocol.java
+++ b/src/main/java/org/traccar/Protocol.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2018 Anton Tananaev (anton@traccar.org)
+ * Copyright 2018 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,9 +15,10 @@
  */
 package org.traccar;
 
-import org.traccar.database.ActiveDevice;
+import io.netty.channel.Channel;
 import org.traccar.model.Command;
 
+import java.net.SocketAddress;
 import java.util.Collection;
 
 public interface Protocol {
@@ -28,7 +29,7 @@ public interface Protocol {
 
     Collection<String> getSupportedDataCommands();
 
-    void sendDataCommand(ActiveDevice activeDevice, Command command);
+    void sendDataCommand(Channel channel, SocketAddress remoteAddress, Command command);
 
     Collection<String> getSupportedTextCommands();
 
diff --git a/src/main/java/org/traccar/WebDataHandler.java b/src/main/java/org/traccar/WebDataHandler.java
index 64396de03..d6bfb126b 100644
--- a/src/main/java/org/traccar/WebDataHandler.java
+++ b/src/main/java/org/traccar/WebDataHandler.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 - 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2015 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -18,6 +18,12 @@ package org.traccar;
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import io.netty.channel.ChannelHandler;
+import io.netty.util.Timer;
+import io.netty.util.Timeout;
+import io.netty.util.TimerTask;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import org.traccar.config.Config;
 import org.traccar.config.Keys;
 import org.traccar.database.IdentityManager;
@@ -27,9 +33,13 @@ import org.traccar.model.Position;
 import org.traccar.model.Group;
 
 import javax.inject.Inject;
+import javax.ws.rs.core.HttpHeaders;
+import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.Response;
 import javax.ws.rs.client.Client;
 import javax.ws.rs.client.Entity;
 import javax.ws.rs.client.Invocation;
+import javax.ws.rs.client.InvocationCallback;
 import java.util.HashMap;
 import java.util.Map;
 import java.io.UnsupportedEncodingException;
@@ -39,10 +49,14 @@ import java.util.Calendar;
 import java.util.Formatter;
 import java.util.Locale;
 import java.util.TimeZone;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicInteger;
 
 @ChannelHandler.Sharable
 public class WebDataHandler extends BaseDataHandler {
 
+    private static final Logger LOGGER = LoggerFactory.getLogger(WebDataHandler.class);
+
     private static final String KEY_POSITION = "position";
     private static final String KEY_DEVICE = "device";
 
@@ -53,16 +67,33 @@ public class WebDataHandler extends BaseDataHandler {
     private final String url;
     private final String header;
     private final boolean json;
+    private final boolean urlVariables;
+
+    private final boolean retryEnabled;
+    private final int retryDelay;
+    private final int retryCount;
+    private final int retryLimit;
+
+    private AtomicInteger deliveryPending;
 
     @Inject
     public WebDataHandler(
             Config config, IdentityManager identityManager, ObjectMapper objectMapper, Client client) {
+
         this.identityManager = identityManager;
         this.objectMapper = objectMapper;
         this.client = client;
         this.url = config.getString(Keys.FORWARD_URL);
         this.header = config.getString(Keys.FORWARD_HEADER);
         this.json = config.getBoolean(Keys.FORWARD_JSON);
+        this.urlVariables = config.getBoolean(Keys.FORWARD_URL_VARIABLES);
+
+        this.retryEnabled = config.getBoolean(Keys.FORWARD_RETRY_ENABLE);
+        this.retryDelay = config.getInteger(Keys.FORWARD_RETRY_DELAY, 100);
+        this.retryCount = config.getInteger(Keys.FORWARD_RETRY_COUNT, 10);
+        this.retryLimit = config.getInteger(Keys.FORWARD_RETRY_LIMIT, 100);
+
+        this.deliveryPending = new AtomicInteger(0);
     }
 
     private static String formatSentence(Position position) {
@@ -152,35 +183,111 @@ public class WebDataHandler extends BaseDataHandler {
         return request;
     }
 
-    @Override
-    protected Position handlePosition(Position position) {
+    class AsyncRequestAndCallback implements InvocationCallback<Response>, TimerTask {
 
-        String url;
-        if (json) {
-            url = this.url;
-        } else {
+        private int retries = 0;
+        private Map<String, Object> payload;
+        private Invocation.Builder requestBuilder;
+        private MediaType mediaType = MediaType.APPLICATION_JSON_TYPE;
+
+        AsyncRequestAndCallback(Position position) {
+
+            String formattedUrl;
             try {
-                url = formatRequest(position);
+                formattedUrl = (json && !urlVariables) ? url : formatRequest(position);
             } catch (UnsupportedEncodingException | JsonProcessingException e) {
                 throw new RuntimeException("Forwarding formatting error", e);
             }
+
+            requestBuilder = client.target(formattedUrl).request();
+            if (header != null && !header.isEmpty()) {
+                for (String line: header.split("\\r?\\n")) {
+                    String[] values = line.split(":", 2);
+                    String headerName = values[0].trim();
+                    String headerValue = values[1].trim();
+                    if (headerName.equals(HttpHeaders.CONTENT_TYPE)) {
+                        mediaType = MediaType.valueOf(headerValue);
+                    } else {
+                        requestBuilder.header(headerName, headerValue);
+                    }
+                }
+            }
+
+            if (json) {
+                payload = prepareJsonPayload(position);
+            }
+
+            deliveryPending.incrementAndGet();
         }
 
-        Invocation.Builder requestBuilder = client.target(url).request();
+        private void send() {
+            if (json) {
+                try {
+                    Entity<String> entity = Entity.entity(objectMapper.writeValueAsString(payload), mediaType);
+                    requestBuilder.async().post(entity, this);
+                } catch (JsonProcessingException e) {
+                    throw new RuntimeException("Failed to serialize location to json", e);
+                }
+            } else {
+                requestBuilder.async().get(this);
+            }
+        }
 
-        if (header != null && !header.isEmpty()) {
-            for (String line: header.split("\\r?\\n")) {
-                String[] values = line.split(":", 2);
-                requestBuilder.header(values[0].trim(), values[1].trim());
+        private void retry() {
+            boolean scheduled = false;
+            try {
+                if (retryEnabled && deliveryPending.get() <= retryLimit && retries < retryCount) {
+                    schedule();
+                    scheduled = true;
+                }
+            } finally {
+                int pending = scheduled ? deliveryPending.get() : deliveryPending.decrementAndGet();
+                LOGGER.warn("Position forwarding failed: " + pending + " pending");
             }
         }
 
-        if (json) {
-            requestBuilder.async().post(Entity.json(prepareJsonPayload(position)));
-        } else {
-            requestBuilder.async().get();
+        private void schedule() {
+            Main.getInjector().getInstance(Timer.class).newTimeout(
+                this, retryDelay * (int) Math.pow(2, retries++), TimeUnit.MILLISECONDS);
+        }
+
+        @Override
+        public void completed(Response response) {
+            if (response.getStatusInfo().getFamily() == Response.Status.Family.SUCCESSFUL) {
+                deliveryPending.decrementAndGet();
+            } else {
+                retry();
+            }
+        }
+
+        @Override
+        public void failed(Throwable throwable) {
+            retry();
+        }
+
+        @Override
+        public void run(Timeout timeout) {
+            boolean sent = false;
+            try {
+                if (!timeout.isCancelled()) {
+                    send();
+                    sent = true;
+                }
+            } finally {
+                if (!sent) {
+                    deliveryPending.decrementAndGet();
+                }
+            }
         }
 
+    }
+
+    @Override
+    protected Position handlePosition(Position position) {
+
+        AsyncRequestAndCallback request = new AsyncRequestAndCallback(position);
+        request.send();
+
         return position;
     }
 
diff --git a/src/main/java/org/traccar/api/ExtendedObjectResource.java b/src/main/java/org/traccar/api/ExtendedObjectResource.java
index 007a7b1bd..9e554217e 100644
--- a/src/main/java/org/traccar/api/ExtendedObjectResource.java
+++ b/src/main/java/org/traccar/api/ExtendedObjectResource.java
@@ -55,8 +55,8 @@ public class ExtendedObjectResource<T extends BaseModel> extends BaseObjectResou
             Context.getPermissionsManager().checkDevice(getUserId(), deviceId);
             result.retainAll(manager.getDeviceItems(deviceId));
         }
-        return manager.getItems(result);
 
+        return manager.getItems(result);
     }
 
 }
diff --git a/src/main/java/org/traccar/api/HealthCheckService.java b/src/main/java/org/traccar/api/HealthCheckService.java
new file mode 100644
index 000000000..1e8f0d731
--- /dev/null
+++ b/src/main/java/org/traccar/api/HealthCheckService.java
@@ -0,0 +1,91 @@
+/*
+ * Copyright 2020 Anton Tananaev (anton@traccar.org)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.traccar.api;
+
+import com.sun.jna.Library;
+import com.sun.jna.Native;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.traccar.Context;
+
+import java.util.TimerTask;
+
+public class HealthCheckService {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(HealthCheckService.class);
+
+    private SystemD systemD;
+
+    private boolean enabled;
+    private long period;
+
+    public HealthCheckService() {
+        if (Context.getConfig().getBoolean("web.healthCheck")
+                && System.getProperty("os.name").toLowerCase().startsWith("linux")) {
+            try {
+                systemD = Native.load("systemd", SystemD.class);
+                String watchdogTimer = System.getenv("WATCHDOG_USEC");
+                if (watchdogTimer != null && !watchdogTimer.isEmpty()) {
+                    period = Long.parseLong(watchdogTimer) / 1000 * 4 / 5;
+                }
+                if (period > 0) {
+                    LOGGER.info("Health check enabled with period {}", period);
+                    enabled = true;
+                }
+            } catch (UnsatisfiedLinkError e) {
+                LOGGER.warn("No systemd support", e);
+            }
+        }
+    }
+
+    public boolean isEnabled() {
+        return enabled;
+    }
+
+    public long getPeriod() {
+        return period;
+    }
+
+    private String getUrl() {
+        String address = Context.getConfig().getString("web.address", "localhost");
+        int port = Context.getConfig().getInteger("web.port", 8082);
+        return "http://" + address + ":" + port + "/api/server";
+    }
+
+    public TimerTask createTask() {
+        return new TimerTask() {
+            @Override
+            public void run() {
+                LOGGER.debug("Health check running");
+                int status = Context.getClient().target(getUrl()).request().get().getStatus();
+                if (status == 200) {
+                    int result = systemD.sd_notify(0, "WATCHDOG=1");
+                    if (result < 0) {
+                        LOGGER.warn("Health check notify error {}", result);
+                    }
+                } else {
+                    LOGGER.warn("Health check failed with status {}", status);
+                }
+            }
+        };
+    }
+
+    interface SystemD extends Library {
+        @SuppressWarnings("checkstyle:MethodName")
+        int sd_notify(@SuppressWarnings("checkstyle:ParameterName") int unset_environment, String state);
+    }
+
+}
diff --git a/src/main/java/org/traccar/api/resource/PositionResource.java b/src/main/java/org/traccar/api/resource/PositionResource.java
index c031b842f..67aa6dd32 100644
--- a/src/main/java/org/traccar/api/resource/PositionResource.java
+++ b/src/main/java/org/traccar/api/resource/PositionResource.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 - 2016 Anton Tananaev (anton@traccar.org)
+ * Copyright 2015 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -34,6 +34,7 @@ import javax.ws.rs.core.Response;
 import java.sql.SQLException;
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.List;
 
 @Path("positions")
@@ -63,8 +64,12 @@ public class PositionResource extends BaseResource {
             return Context.getDeviceManager().getInitialState(getUserId());
         } else {
             Context.getPermissionsManager().checkDevice(getUserId(), deviceId);
-            return Context.getDataManager().getPositions(
-                    deviceId, DateUtil.parseDate(from), DateUtil.parseDate(to));
+            if (from != null && to != null) {
+                return Context.getDataManager().getPositions(
+                        deviceId, DateUtil.parseDate(from), DateUtil.parseDate(to));
+            } else {
+                return Collections.singleton(Context.getDeviceManager().getLastPosition(deviceId));
+            }
         }
     }
 
diff --git a/src/main/java/org/traccar/config/Keys.java b/src/main/java/org/traccar/config/Keys.java
index 2c5dcefd5..200ef8aa3 100644
--- a/src/main/java/org/traccar/config/Keys.java
+++ b/src/main/java/org/traccar/config/Keys.java
@@ -101,6 +101,44 @@ public final class Keys {
             "forward.json", Boolean.class);
 
     /**
+     * Boolean value to enable URL parameters in json mode. For example, {uniqueId} for device identifier,
+     * {latitude} and {longitude} for coordinates.
+     */
+    public static final ConfigKey FORWARD_URL_VARIABLES = new ConfigKey(
+        "forward.urlVariables", Boolean.class);
+
+    /**
+     * Position forwarding retrying enable. When enabled, additional attempts are made to deliver positions. If initial
+     * delivery fails, because of an unreachable server or an HTTP response different from '2xx', the software waits
+     * for 'forward.retry.delay' milliseconds to retry delivery. On subsequent failures, this delay is duplicated.
+     * If forwarding is retried for 'forward.retry.count', retrying is canceled and the position is dropped. Positions
+     * pending to be delivered are limited to 'forward.retry.limit'. If this limit is reached, positions get discarded.
+     */
+    public static final ConfigKey FORWARD_RETRY_ENABLE = new ConfigKey(
+            "forward.retry.enable", Boolean.class);
+
+    /**
+     * Position forwarding retry first delay in milliseconds.
+     * Can be set to anything greater than 0. Defaults to 100 milliseconds.
+     */
+    public static final ConfigKey FORWARD_RETRY_DELAY = new ConfigKey(
+            "forward.retry.delay", Integer.class);
+
+    /**
+     * Position forwarding retry maximum retries.
+     * Can be set to anything greater than 0. Defaults to 10 retries.
+     */
+    public static final ConfigKey FORWARD_RETRY_COUNT = new ConfigKey(
+            "forward.retry.count", Integer.class);
+
+    /**
+     * Position forwarding retry pending positions limit.
+     * Can be set to anything greater than 0. Defaults to 100 positions.
+     */
+    public static final ConfigKey FORWARD_RETRY_LIMIT = new ConfigKey(
+            "forward.retry.limit", Integer.class);
+
+    /**
      * Boolean flag to enable or disable position filtering.
      */
     public static final ConfigKey FILTER_ENABLE = new ConfigKey(
diff --git a/src/main/java/org/traccar/database/ActiveDevice.java b/src/main/java/org/traccar/database/ActiveDevice.java
index 207fc454b..e3ece6ad9 100644
--- a/src/main/java/org/traccar/database/ActiveDevice.java
+++ b/src/main/java/org/traccar/database/ActiveDevice.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 - 2018 Anton Tananaev (anton@traccar.org)
+ * Copyright 2015 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,7 +16,8 @@
 package org.traccar.database;
 
 import io.netty.channel.Channel;
-import org.traccar.NetworkMessage;
+import io.netty.handler.codec.http.HttpRequestDecoder;
+import org.traccar.BasePipelineFactory;
 import org.traccar.Protocol;
 import org.traccar.model.Command;
 
@@ -44,12 +45,12 @@ public class ActiveDevice {
         return deviceId;
     }
 
-    public void sendCommand(Command command) {
-        protocol.sendDataCommand(this, command);
+    public boolean supportsLiveCommands() {
+        return BasePipelineFactory.getHandler(channel.pipeline(), HttpRequestDecoder.class) == null;
     }
 
-    public void write(Object message) {
-        channel.writeAndFlush(new NetworkMessage(message, remoteAddress));
+    public void sendCommand(Command command) {
+        protocol.sendDataCommand(channel, remoteAddress, command);
     }
 
 }
diff --git a/src/main/java/org/traccar/database/BaseObjectManager.java b/src/main/java/org/traccar/database/BaseObjectManager.java
index 8bf9ef860..e274e5aba 100644
--- a/src/main/java/org/traccar/database/BaseObjectManager.java
+++ b/src/main/java/org/traccar/database/BaseObjectManager.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 - 2020 Anton Tananaev (anton@traccar.org)
  * Copyright 2017 Andrey Kunitsyn (andrey@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -23,6 +23,8 @@ import java.util.LinkedList;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.locks.ReadWriteLock;
+import java.util.concurrent.locks.ReentrantReadWriteLock;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -32,6 +34,8 @@ public class BaseObjectManager<T extends BaseModel> {
 
     private static final Logger LOGGER = LoggerFactory.getLogger(BaseObjectManager.class);
 
+    private final ReadWriteLock lock = new ReentrantReadWriteLock();
+
     private final DataManager dataManager;
 
     private Map<Long, T> items;
@@ -43,6 +47,22 @@ public class BaseObjectManager<T extends BaseModel> {
         refreshItems();
     }
 
+    protected final void readLock() {
+        lock.readLock().lock();
+    }
+
+    protected final void readUnlock() {
+        lock.readLock().unlock();
+    }
+
+    protected final void writeLock() {
+        lock.writeLock().lock();
+    }
+
+    protected final void writeUnlock() {
+        lock.writeLock().unlock();
+    }
+
     protected final DataManager getDataManager() {
         return dataManager;
     }
@@ -52,12 +72,18 @@ public class BaseObjectManager<T extends BaseModel> {
     }
 
     public T getById(long itemId) {
-        return items.get(itemId);
+        try {
+            readLock();
+            return items.get(itemId);
+        } finally {
+            readUnlock();
+        }
     }
 
     public void refreshItems() {
         if (dataManager != null) {
             try {
+                writeLock();
                 Collection<T> databaseItems = dataManager.getObjects(baseClass);
                 if (items == null) {
                     items = new ConcurrentHashMap<>(databaseItems.size());
@@ -78,12 +104,19 @@ public class BaseObjectManager<T extends BaseModel> {
                 }
             } catch (SQLException error) {
                 LOGGER.warn("Error refreshing items", error);
+            } finally {
+                writeUnlock();
             }
         }
     }
 
     protected void addNewItem(T item) {
-        items.put(item.getId(), item);
+        try {
+            writeLock();
+            items.put(item.getId(), item);
+        } finally {
+            writeUnlock();
+        }
     }
 
     public void addItem(T item) throws SQLException {
@@ -92,7 +125,12 @@ public class BaseObjectManager<T extends BaseModel> {
     }
 
     protected void updateCachedItem(T item) {
-        items.put(item.getId(), item);
+        try {
+            writeLock();
+            items.put(item.getId(), item);
+        } finally {
+            writeUnlock();
+        }
     }
 
     public void updateItem(T item) throws SQLException {
@@ -101,7 +139,12 @@ public class BaseObjectManager<T extends BaseModel> {
     }
 
     protected void removeCachedItem(long itemId) {
-        items.remove(itemId);
+        try {
+            writeLock();
+            items.remove(itemId);
+        } finally {
+            writeUnlock();
+        }
     }
 
     public void removeItem(long itemId) throws SQLException {
@@ -121,7 +164,12 @@ public class BaseObjectManager<T extends BaseModel> {
     }
 
     public Set<Long> getAllItems() {
-        return items.keySet();
+        try {
+            readLock();
+            return items.keySet();
+        } finally {
+            readUnlock();
+        }
     }
 
 }
diff --git a/src/main/java/org/traccar/database/CommandsManager.java b/src/main/java/org/traccar/database/CommandsManager.java
index dc9512d9e..485402807 100644
--- a/src/main/java/org/traccar/database/CommandsManager.java
+++ b/src/main/java/org/traccar/database/CommandsManager.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 - 2020 Anton Tananaev (anton@traccar.org)
  * Copyright 2017 Andrey Kunitsyn (andrey@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -76,7 +76,12 @@ public class CommandsManager  extends ExtendedObjectManager<Command> {
         } else {
             ActiveDevice activeDevice = Context.getConnectionManager().getActiveDevice(deviceId);
             if (activeDevice != null) {
-                activeDevice.sendCommand(command);
+                if (activeDevice.supportsLiveCommands()) {
+                    activeDevice.sendCommand(command);
+                } else {
+                    getDeviceQueue(deviceId).add(command);
+                    return false;
+                }
             } else if (!queueing) {
                 throw new RuntimeException("Device is not online");
             } else {
@@ -142,21 +147,46 @@ public class CommandsManager  extends ExtendedObjectManager<Command> {
     }
 
     private Queue<Command> getDeviceQueue(long deviceId) {
-        if (!deviceQueues.containsKey(deviceId)) {
-            deviceQueues.put(deviceId, new ConcurrentLinkedQueue<Command>());
+        Queue<Command> deviceQueue;
+        try {
+            readLock();
+            deviceQueue = deviceQueues.get(deviceId);
+        } finally {
+            readUnlock();
+        }
+        if (deviceQueue != null) {
+            return deviceQueue;
+        } else {
+            try {
+                writeLock();
+                return deviceQueues.computeIfAbsent(deviceId, key -> new ConcurrentLinkedQueue<>());
+            } finally {
+                writeUnlock();
+            }
         }
-        return deviceQueues.get(deviceId);
     }
 
-    public void sendQueuedCommands(ActiveDevice activeDevice) {
-        Queue<Command> deviceQueue = deviceQueues.get(activeDevice.getDeviceId());
+    public Collection<Command> readQueuedCommands(long deviceId) {
+        return readQueuedCommands(deviceId, Integer.MAX_VALUE);
+    }
+
+    public Collection<Command> readQueuedCommands(long deviceId, int count) {
+        Queue<Command> deviceQueue;
+        try {
+            readLock();
+            deviceQueue = deviceQueues.get(deviceId);
+        } finally {
+            readUnlock();
+        }
+        Collection<Command> result = new ArrayList<>();
         if (deviceQueue != null) {
             Command command = deviceQueue.poll();
-            while (command != null) {
-                activeDevice.sendCommand(command);
+            while (command != null && result.size() < count) {
+                result.add(command);
                 command = deviceQueue.poll();
             }
         }
+        return result;
     }
 
 }
diff --git a/src/main/java/org/traccar/database/ConnectionManager.java b/src/main/java/org/traccar/database/ConnectionManager.java
index dd0071143..4d43bc71b 100644
--- a/src/main/java/org/traccar/database/ConnectionManager.java
+++ b/src/main/java/org/traccar/database/ConnectionManager.java
@@ -139,10 +139,6 @@ public class ConnectionManager {
         }
 
         updateDevice(device);
-
-        if (status.equals(Device.STATUS_ONLINE) && !oldStatus.equals(Device.STATUS_ONLINE)) {
-            Context.getCommandsManager().sendQueuedCommands(getActiveDevice(deviceId));
-        }
     }
 
     public Map<Event, Position> updateDeviceState(long deviceId) {
diff --git a/src/main/java/org/traccar/database/DeviceManager.java b/src/main/java/org/traccar/database/DeviceManager.java
index fa95adeb2..fe17f7ced 100644
--- a/src/main/java/org/traccar/database/DeviceManager.java
+++ b/src/main/java/org/traccar/database/DeviceManager.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016 - 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2016 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -58,11 +58,16 @@ public class DeviceManager extends BaseObjectManager<Device> implements Identity
     public DeviceManager(DataManager dataManager) {
         super(dataManager, Device.class);
         this.config = Context.getConfig();
-        if (devicesByPhone == null) {
-            devicesByPhone = new ConcurrentHashMap<>();
-        }
-        if (devicesByUniqueId == null) {
-            devicesByUniqueId = new ConcurrentHashMap<>();
+        try {
+            writeLock();
+            if (devicesByPhone == null) {
+                devicesByPhone = new ConcurrentHashMap<>();
+            }
+            if (devicesByUniqueId == null) {
+                devicesByUniqueId = new ConcurrentHashMap<>();
+            }
+        } finally {
+            writeUnlock();
         }
         dataRefreshDelay = config.getLong("database.refreshDelay", DEFAULT_REFRESH_DELAY) * 1000;
         lookupGroupsAttribute = config.getBoolean("deviceManager.lookupGroupsAttribute");
@@ -108,11 +113,20 @@ public class DeviceManager extends BaseObjectManager<Device> implements Identity
 
     @Override
     public Device getByUniqueId(String uniqueId) throws SQLException {
-        boolean forceUpdate = !devicesByUniqueId.containsKey(uniqueId) && !config.getBoolean("database.ignoreUnknown");
-
+        boolean forceUpdate;
+        try {
+            readLock();
+            forceUpdate = !devicesByUniqueId.containsKey(uniqueId) && !config.getBoolean("database.ignoreUnknown");
+        } finally {
+            readUnlock();
+        }
         updateDeviceCache(forceUpdate);
-
-        return devicesByUniqueId.get(uniqueId);
+        try {
+            readLock();
+            return devicesByUniqueId.get(uniqueId);
+        } finally {
+            readUnlock();
+        }
     }
 
     @Override
@@ -134,7 +148,12 @@ public class DeviceManager extends BaseObjectManager<Device> implements Identity
     }
 
     public Device getDeviceByPhone(String phone) {
-        return devicesByPhone.get(phone);
+        try {
+            readLock();
+            return devicesByPhone.get(phone);
+        } finally {
+            readUnlock();
+        }
     }
 
     @Override
@@ -176,8 +195,7 @@ public class DeviceManager extends BaseObjectManager<Device> implements Identity
     }
 
     public Set<Long> getAllManagedItems(long userId) {
-        Set<Long> result = new HashSet<>();
-        result.addAll(getAllUserItems(userId));
+        Set<Long> result = new HashSet<>(getAllUserItems(userId));
         for (long managedUserId : Context.getUsersManager().getUserItems(userId)) {
             result.addAll(getAllUserItems(managedUserId));
         }
@@ -186,34 +204,68 @@ public class DeviceManager extends BaseObjectManager<Device> implements Identity
 
     @Override
     public Set<Long> getManagedItems(long userId) {
-        Set<Long> result = new HashSet<>();
-        result.addAll(getUserItems(userId));
+        Set<Long> result = new HashSet<>(getUserItems(userId));
         for (long managedUserId : Context.getUsersManager().getUserItems(userId)) {
             result.addAll(getUserItems(managedUserId));
         }
         return result;
     }
 
-    private void putUniqueDeviceId(Device device) {
-        if (devicesByUniqueId == null) {
-            devicesByUniqueId = new ConcurrentHashMap<>(getAllItems().size());
+    private void addByUniqueId(Device device) {
+        try {
+            writeLock();
+            if (devicesByUniqueId == null) {
+                devicesByUniqueId = new ConcurrentHashMap<>();
+            }
+            devicesByUniqueId.put(device.getUniqueId(), device);
+        } finally {
+            writeUnlock();
+        }
+    }
+
+    private void removeByUniqueId(String deviceUniqueId) {
+        try {
+            writeLock();
+            if (devicesByUniqueId != null) {
+                devicesByUniqueId.remove(deviceUniqueId);
+            }
+        } finally {
+            writeUnlock();
+        }
+    }
+
+    private void addByPhone(Device device) {
+        try {
+            writeLock();
+            if (devicesByPhone == null) {
+                devicesByPhone = new ConcurrentHashMap<>();
+            }
+            devicesByPhone.put(device.getPhone(), device);
+        } finally {
+            writeUnlock();
         }
-        devicesByUniqueId.put(device.getUniqueId(), device);
     }
 
-    private void putPhone(Device device) {
-        if (devicesByPhone == null) {
-            devicesByPhone = new ConcurrentHashMap<>(getAllItems().size());
+    private void removeByPhone(String phone) {
+        if (phone == null || phone.isEmpty()) {
+            return;
+        }
+        try {
+            writeLock();
+            if (devicesByPhone != null) {
+                devicesByPhone.remove(phone);
+            }
+        } finally {
+            writeUnlock();
         }
-        devicesByPhone.put(device.getPhone(), device);
     }
 
     @Override
     protected void addNewItem(Device device) {
         super.addNewItem(device);
-        putUniqueDeviceId(device);
+        addByUniqueId(device);
         if (device.getPhone() != null  && !device.getPhone().isEmpty()) {
-            putPhone(device);
+            addByPhone(device);
         }
         if (Context.getGeofenceManager() != null) {
             Position lastPosition = getLastPosition(device.getId());
@@ -234,18 +286,16 @@ public class DeviceManager extends BaseObjectManager<Device> implements Identity
         cachedDevice.setDisabled(device.getDisabled());
         cachedDevice.setAttributes(device.getAttributes());
         if (!device.getUniqueId().equals(cachedDevice.getUniqueId())) {
-            devicesByUniqueId.remove(cachedDevice.getUniqueId());
+            removeByUniqueId(cachedDevice.getUniqueId());
             cachedDevice.setUniqueId(device.getUniqueId());
-            putUniqueDeviceId(cachedDevice);
+            addByUniqueId(cachedDevice);
         }
         if (device.getPhone() != null && !device.getPhone().isEmpty()
                 && !device.getPhone().equals(cachedDevice.getPhone())) {
             String phone = cachedDevice.getPhone();
-            if (phone != null && !phone.isEmpty()) {
-                devicesByPhone.remove(phone);
-            }
+            removeByPhone(phone);
             cachedDevice.setPhone(device.getPhone());
-            putPhone(cachedDevice);
+            addByPhone(cachedDevice);
         }
     }
 
@@ -256,10 +306,8 @@ public class DeviceManager extends BaseObjectManager<Device> implements Identity
             String deviceUniqueId = cachedDevice.getUniqueId();
             String phone = cachedDevice.getPhone();
             super.removeCachedItem(deviceId);
-            devicesByUniqueId.remove(deviceUniqueId);
-            if (phone != null && !phone.isEmpty()) {
-                devicesByPhone.remove(phone);
-            }
+            removeByUniqueId(deviceUniqueId);
+            removeByPhone(phone);
         }
         positions.remove(deviceId);
     }
diff --git a/src/main/java/org/traccar/database/DriversManager.java b/src/main/java/org/traccar/database/DriversManager.java
index 930951460..d111cd643 100644
--- a/src/main/java/org/traccar/database/DriversManager.java
+++ b/src/main/java/org/traccar/database/DriversManager.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 - 2020 Anton Tananaev (anton@traccar.org)
  * Copyright 2017 Andrey Kunitsyn (andrey@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -27,22 +27,44 @@ public class DriversManager extends ExtendedObjectManager<Driver> {
 
     public DriversManager(DataManager dataManager) {
         super(dataManager, Driver.class);
-        if (driversByUniqueId == null) {
-            driversByUniqueId = new ConcurrentHashMap<>();
+        try {
+            writeLock();
+            if (driversByUniqueId == null) {
+                driversByUniqueId = new ConcurrentHashMap<>();
+            }
+        } finally {
+            writeUnlock();
         }
     }
 
-    private void putUniqueDriverId(Driver driver) {
-        if (driversByUniqueId == null) {
-            driversByUniqueId = new ConcurrentHashMap<>(getAllItems().size());
+    private void addByUniqueId(Driver driver) {
+        try {
+            writeLock();
+            if (driversByUniqueId == null) {
+                driversByUniqueId = new ConcurrentHashMap<>();
+            }
+            driversByUniqueId.put(driver.getUniqueId(), driver);
+        } finally {
+            writeUnlock();
+        }
+    }
+
+    private void removeByUniqueId(String driverUniqueId) {
+        try {
+            writeLock();
+            if (driversByUniqueId == null) {
+                driversByUniqueId = new ConcurrentHashMap<>();
+            }
+            driversByUniqueId.remove(driverUniqueId);
+        } finally {
+            writeUnlock();
         }
-        driversByUniqueId.put(driver.getUniqueId(), driver);
     }
 
     @Override
     protected void addNewItem(Driver driver) {
         super.addNewItem(driver);
-        putUniqueDriverId(driver);
+        addByUniqueId(driver);
     }
 
     @Override
@@ -50,9 +72,9 @@ public class DriversManager extends ExtendedObjectManager<Driver> {
         Driver cachedDriver = getById(driver.getId());
         cachedDriver.setName(driver.getName());
         if (!driver.getUniqueId().equals(cachedDriver.getUniqueId())) {
-            driversByUniqueId.remove(cachedDriver.getUniqueId());
+            removeByUniqueId(cachedDriver.getUniqueId());
             cachedDriver.setUniqueId(driver.getUniqueId());
-            putUniqueDriverId(cachedDriver);
+            addByUniqueId(cachedDriver);
         }
         cachedDriver.setAttributes(driver.getAttributes());
     }
@@ -63,11 +85,16 @@ public class DriversManager extends ExtendedObjectManager<Driver> {
         if (cachedDriver != null) {
             String driverUniqueId = cachedDriver.getUniqueId();
             super.removeCachedItem(driverId);
-            driversByUniqueId.remove(driverUniqueId);
+            removeByUniqueId(driverUniqueId);
         }
     }
 
     public Driver getDriverByUniqueId(String uniqueId) {
-        return driversByUniqueId.get(uniqueId);
+        try {
+            readLock();
+            return driversByUniqueId.get(uniqueId);
+        } finally {
+            readUnlock();
+        }
     }
 }
diff --git a/src/main/java/org/traccar/database/ExtendedObjectManager.java b/src/main/java/org/traccar/database/ExtendedObjectManager.java
index ceb85b537..93e5820fb 100644
--- a/src/main/java/org/traccar/database/ExtendedObjectManager.java
+++ b/src/main/java/org/traccar/database/ExtendedObjectManager.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 - 2020 Anton Tananaev (anton@traccar.org)
  * Copyright 2017 Andrey Kunitsyn (andrey@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -45,24 +45,45 @@ public abstract class ExtendedObjectManager<T extends BaseModel> extends SimpleO
     }
 
     public final Set<Long> getGroupItems(long groupId) {
-        if (!groupItems.containsKey(groupId)) {
-            groupItems.put(groupId, new HashSet<Long>());
+        try {
+            readLock();
+            Set<Long> result = groupItems.get(groupId);
+            if (result != null) {
+                return new HashSet<>(result);
+            } else {
+                return new HashSet<>();
+            }
+        } finally {
+            readUnlock();
         }
-        return groupItems.get(groupId);
     }
 
     public final Set<Long> getDeviceItems(long deviceId) {
-        if (!deviceItems.containsKey(deviceId)) {
-            deviceItems.put(deviceId, new HashSet<Long>());
+        try {
+            readLock();
+            Set<Long> result = deviceItems.get(deviceId);
+            if (result != null) {
+                return new HashSet<>(result);
+            } else {
+                return new HashSet<>();
+            }
+        } finally {
+            readUnlock();
         }
-        return deviceItems.get(deviceId);
     }
 
     public Set<Long> getAllDeviceItems(long deviceId) {
-        if (!deviceItemsWithGroups.containsKey(deviceId)) {
-            deviceItemsWithGroups.put(deviceId, new HashSet<Long>());
+        try {
+            readLock();
+            Set<Long> result = deviceItemsWithGroups.get(deviceId);
+            if (result != null) {
+                return new HashSet<>(result);
+            } else {
+                return new HashSet<>();
+            }
+        } finally {
+            readUnlock();
         }
-        return deviceItemsWithGroups.get(deviceId);
     }
 
     @Override
@@ -74,41 +95,48 @@ public abstract class ExtendedObjectManager<T extends BaseModel> extends SimpleO
     public void refreshExtendedPermissions() {
         if (getDataManager() != null) {
             try {
-
                 Collection<Permission> databaseGroupPermissions =
                         getDataManager().getPermissions(Group.class, getBaseClass());
 
-                groupItems.clear();
-                for (Permission groupPermission : databaseGroupPermissions) {
-                    getGroupItems(groupPermission.getOwnerId()).add(groupPermission.getPropertyId());
-                }
-
                 Collection<Permission> databaseDevicePermissions =
                         getDataManager().getPermissions(Device.class, getBaseClass());
 
+                writeLock();
+
+                groupItems.clear();
                 deviceItems.clear();
                 deviceItemsWithGroups.clear();
 
+                for (Permission groupPermission : databaseGroupPermissions) {
+                    groupItems
+                            .computeIfAbsent(groupPermission.getOwnerId(), key -> new HashSet<>())
+                            .add(groupPermission.getPropertyId());
+                }
+
                 for (Permission devicePermission : databaseDevicePermissions) {
-                    getDeviceItems(devicePermission.getOwnerId()).add(devicePermission.getPropertyId());
-                    getAllDeviceItems(devicePermission.getOwnerId()).add(devicePermission.getPropertyId());
+                    deviceItems
+                            .computeIfAbsent(devicePermission.getOwnerId(), key -> new HashSet<>())
+                            .add(devicePermission.getPropertyId());
+                    deviceItemsWithGroups
+                            .computeIfAbsent(devicePermission.getOwnerId(), key -> new HashSet<>())
+                            .add(devicePermission.getPropertyId());
                 }
 
                 for (Device device : Context.getDeviceManager().getAllDevices()) {
                     long groupId = device.getGroupId();
-                    while (groupId != 0) {
-                        getAllDeviceItems(device.getId()).addAll(getGroupItems(groupId));
+                    while (groupId > 0) {
+                        deviceItemsWithGroups
+                                .computeIfAbsent(device.getId(), key -> new HashSet<>())
+                                .addAll(groupItems.getOrDefault(groupId, new HashSet<>()));
                         Group group = Context.getGroupsManager().getById(groupId);
-                        if (group != null) {
-                            groupId = group.getGroupId();
-                        } else {
-                            groupId = 0;
-                        }
+                        groupId = group != null ? group.getGroupId() : 0;
                     }
                 }
 
             } catch (SQLException | ClassNotFoundException error) {
                 LOGGER.warn("Refresh permissions error", error);
+            } finally {
+                writeUnlock();
             }
         }
     }
diff --git a/src/main/java/org/traccar/database/GroupsManager.java b/src/main/java/org/traccar/database/GroupsManager.java
index d8404c614..81f1968aa 100644
--- a/src/main/java/org/traccar/database/GroupsManager.java
+++ b/src/main/java/org/traccar/database/GroupsManager.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 - 2020 Anton Tananaev (anton@traccar.org)
  * Copyright 2017 Andrey Kunitsyn (andrey@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -95,8 +95,7 @@ public class GroupsManager extends BaseObjectManager<Group> implements Managable
 
     @Override
     public Set<Long> getManagedItems(long userId) {
-        Set<Long> result = new HashSet<>();
-        result.addAll(getUserItems(userId));
+        Set<Long> result = getUserItems(userId);
         for (long managedUserId : Context.getUsersManager().getUserItems(userId)) {
             result.addAll(getUserItems(managedUserId));
         }
diff --git a/src/main/java/org/traccar/database/LdapProvider.java b/src/main/java/org/traccar/database/LdapProvider.java
index d8b5c9f52..a8220ea8e 100644
--- a/src/main/java/org/traccar/database/LdapProvider.java
+++ b/src/main/java/org/traccar/database/LdapProvider.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -81,7 +81,7 @@ public class LdapProvider {
         if (this.adminFilter != null) {
             try {
                 InitialDirContext context = initContext();
-                String searchString = adminFilter.replace(":login", accountName);
+                String searchString = adminFilter.replace(":login", encodeForLdap(accountName));
                 SearchControls searchControls = new SearchControls();
                 searchControls.setSearchScope(SearchControls.SUBTREE_SCOPE);
                 NamingEnumeration<SearchResult> results = context.search(searchBase, searchString, searchControls);
@@ -107,7 +107,7 @@ public class LdapProvider {
     private SearchResult lookupUser(String accountName) throws NamingException {
         InitialDirContext context = initContext();
 
-        String searchString = searchFilter.replace(":login", accountName);
+        String searchString = searchFilter.replace(":login", encodeForLdap(accountName));
 
         SearchControls searchControls = new SearchControls();
         String[] attributeFilter = {idAttribute, nameAttribute, mailAttribute};
@@ -176,4 +176,34 @@ public class LdapProvider {
         return false;
     }
 
+    public String encodeForLdap(String input) {
+        if (input == null) {
+            return null;
+        }
+        StringBuilder sb = new StringBuilder();
+        for (int i = 0; i < input.length(); i++) {
+            char c = input.charAt(i);
+            switch (c) {
+                case '\\':
+                    sb.append("\\5c");
+                    break;
+                case '*':
+                    sb.append("\\2a");
+                    break;
+                case '(':
+                    sb.append("\\28");
+                    break;
+                case ')':
+                    sb.append("\\29");
+                    break;
+                case '\0':
+                    sb.append("\\00");
+                    break;
+                default:
+                    sb.append(c);
+            }
+        }
+        return sb.toString();
+    }
+
 }
diff --git a/src/main/java/org/traccar/database/SimpleObjectManager.java b/src/main/java/org/traccar/database/SimpleObjectManager.java
index 15dda4520..eb8284d4e 100644
--- a/src/main/java/org/traccar/database/SimpleObjectManager.java
+++ b/src/main/java/org/traccar/database/SimpleObjectManager.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 - 2020 Anton Tananaev (anton@traccar.org)
  * Copyright 2017 Andrey Kunitsyn (andrey@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -42,16 +42,22 @@ public abstract class SimpleObjectManager<T extends BaseModel> extends BaseObjec
 
     @Override
     public final Set<Long> getUserItems(long userId) {
-        if (!userItems.containsKey(userId)) {
-            userItems.put(userId, new HashSet<Long>());
+        try {
+            readLock();
+            Set<Long> result = userItems.get(userId);
+            if (result != null) {
+                return new HashSet<>(result);
+            } else {
+                return new HashSet<>();
+            }
+        } finally {
+            readUnlock();
         }
-        return userItems.get(userId);
     }
 
     @Override
     public Set<Long> getManagedItems(long userId) {
-        Set<Long> result = new HashSet<>();
-        result.addAll(getUserItems(userId));
+        Set<Long> result = getUserItems(userId);
         for (long managedUserId : Context.getUsersManager().getUserItems(userId)) {
             result.addAll(getUserItems(managedUserId));
         }
@@ -71,16 +77,16 @@ public abstract class SimpleObjectManager<T extends BaseModel> extends BaseObjec
     public final void refreshUserItems() {
         if (getDataManager() != null) {
             try {
-                if (userItems != null) {
-                    userItems.clear();
-                } else {
-                    userItems = new ConcurrentHashMap<>();
-                }
+                writeLock();
+                userItems = new ConcurrentHashMap<>();
                 for (Permission permission : getDataManager().getPermissions(User.class, getBaseClass())) {
-                    getUserItems(permission.getOwnerId()).add(permission.getPropertyId());
+                    Set<Long> items = userItems.computeIfAbsent(permission.getOwnerId(), key -> new HashSet<>());
+                    items.add(permission.getPropertyId());
                 }
             } catch (SQLException | ClassNotFoundException error) {
                 LOGGER.warn("Error getting permissions", error);
+            } finally {
+                writeUnlock();
             }
         }
     }
diff --git a/src/main/java/org/traccar/database/UsersManager.java b/src/main/java/org/traccar/database/UsersManager.java
index 576a9e6c7..b741a85b6 100644
--- a/src/main/java/org/traccar/database/UsersManager.java
+++ b/src/main/java/org/traccar/database/UsersManager.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 - 2020 Anton Tananaev (anton@traccar.org)
  * Copyright 2017 Andrey Kunitsyn (andrey@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -16,7 +16,6 @@
  */
 package org.traccar.database;
 
-import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
@@ -73,8 +72,7 @@ public class UsersManager extends SimpleObjectManager<User> {
 
     @Override
     public Set<Long> getManagedItems(long userId) {
-        Set<Long> result = new HashSet<>();
-        result.addAll(getUserItems(userId));
+        Set<Long> result = getUserItems(userId);
         result.add(userId);
         return result;
     }
diff --git a/src/main/java/org/traccar/geocoder/FactualGeocoder.java b/src/main/java/org/traccar/geocoder/FactualGeocoder.java
index c7a68c293..f540eb8fe 100644
--- a/src/main/java/org/traccar/geocoder/FactualGeocoder.java
+++ b/src/main/java/org/traccar/geocoder/FactualGeocoder.java
@@ -1,6 +1,6 @@
 /*
  * Copyright 2014 - 2015 Stefaan Van Dooren (stefaan.vandooren@gmail.com)
- * Copyright 2017 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -20,8 +20,16 @@ import javax.json.JsonObject;
 
 public class FactualGeocoder extends JsonGeocoder {
 
+    private static String formatUrl(String url, String key) {
+        if (url == null) {
+            url = "https://api.factual.com/geotag";
+        }
+        url += "?latitude=%f&longitude=%f&KEY=" + key;
+        return url;
+    }
+
     public FactualGeocoder(String url, String key, int cacheSize, AddressFormat addressFormat) {
-        super(url + "?latitude=%f&longitude=%f&KEY=" + key, cacheSize, addressFormat);
+        super(formatUrl(url, key), cacheSize, addressFormat);
     }
 
     @Override
diff --git a/src/main/java/org/traccar/geocoder/GisgraphyGeocoder.java b/src/main/java/org/traccar/geocoder/GisgraphyGeocoder.java
index 3a173f985..b4881a006 100644
--- a/src/main/java/org/traccar/geocoder/GisgraphyGeocoder.java
+++ b/src/main/java/org/traccar/geocoder/GisgraphyGeocoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 - 2017 Anton Tananaev (anton@traccar.org)
+ * Copyright 2015 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,12 +19,16 @@ import javax.json.JsonObject;
 
 public class GisgraphyGeocoder extends JsonGeocoder {
 
-    public GisgraphyGeocoder(AddressFormat addressFormat) {
-        this("http://services.gisgraphy.com/reversegeocoding/search", 0, addressFormat);
+    private static String formatUrl(String url) {
+        if (url == null) {
+            url = "http://services.gisgraphy.com/reversegeocoding/search";
+        }
+        url += "?format=json&lat=%f&lng=%f&from=1&to=1";
+        return url;
     }
 
     public GisgraphyGeocoder(String url, int cacheSize, AddressFormat addressFormat) {
-        super(url + "?format=json&lat=%f&lng=%f&from=1&to=1", cacheSize, addressFormat);
+        super(formatUrl(url), cacheSize, addressFormat);
     }
 
     @Override
diff --git a/src/main/java/org/traccar/geocoder/MapQuestGeocoder.java b/src/main/java/org/traccar/geocoder/MapQuestGeocoder.java
index 4029e3f07..8dc3f76f0 100644
--- a/src/main/java/org/traccar/geocoder/MapQuestGeocoder.java
+++ b/src/main/java/org/traccar/geocoder/MapQuestGeocoder.java
@@ -1,6 +1,6 @@
 /*
  * Copyright 2014 - 2015 Stefaan Van Dooren (stefaan.vandooren@gmail.com)
- * Copyright 2017 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,8 +21,16 @@ import javax.json.JsonObject;
 
 public class MapQuestGeocoder extends JsonGeocoder {
 
+    private static String formatUrl(String url, String key) {
+        if (url == null) {
+            url = "http://www.mapquestapi.com/geocoding/v1/reverse";
+        }
+        url += "?key=" + key + "&location=%f,%f";
+        return url;
+    }
+
     public MapQuestGeocoder(String url, String key, int cacheSize, AddressFormat addressFormat) {
-        super(url + "?key=" + key + "&location=%f,%f", cacheSize, addressFormat);
+        super(formatUrl(url, key), cacheSize, addressFormat);
     }
 
     @Override
diff --git a/src/main/java/org/traccar/geocoder/OpenCageGeocoder.java b/src/main/java/org/traccar/geocoder/OpenCageGeocoder.java
index 822b6e91e..56161e52c 100644
--- a/src/main/java/org/traccar/geocoder/OpenCageGeocoder.java
+++ b/src/main/java/org/traccar/geocoder/OpenCageGeocoder.java
@@ -1,6 +1,6 @@
 /*
  * Copyright 2014 - 2015 Stefaan Van Dooren (stefaan.vandooren@gmail.com)
- * Copyright 2017 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,8 +21,16 @@ import javax.json.JsonObject;
 
 public class OpenCageGeocoder extends JsonGeocoder {
 
+    private static String formatUrl(String url, String key) {
+        if (url == null) {
+            url = "https://api.opencagedata.com/geocode/v1";
+        }
+        url += "/json?q=%f,%f&no_annotations=1&key=" + key;
+        return url;
+    }
+
     public OpenCageGeocoder(String url, String key, int cacheSize, AddressFormat addressFormat) {
-        super(url + "/json?q=%f,%f&no_annotations=1&key=" + key, cacheSize, addressFormat);
+        super(formatUrl(url, key), cacheSize, addressFormat);
     }
 
     @Override
diff --git a/src/main/java/org/traccar/helper/Checksum.java b/src/main/java/org/traccar/helper/Checksum.java
index adfa697c5..d41dc2992 100644
--- a/src/main/java/org/traccar/helper/Checksum.java
+++ b/src/main/java/org/traccar/helper/Checksum.java
@@ -168,6 +168,14 @@ public final class Checksum {
         return checksum;
     }
 
+    public static int modulo256(ByteBuffer buf) {
+        int checksum = 0;
+        while (buf.hasRemaining()) {
+            checksum = (checksum + buf.get()) & 0xFF;
+        }
+        return checksum;
+    }
+
     public static String sum(String msg) {
         byte checksum = 0;
         for (byte b : msg.getBytes(StandardCharsets.US_ASCII)) {
diff --git a/src/main/java/org/traccar/helper/ServletHelper.java b/src/main/java/org/traccar/helper/ServletHelper.java
index e3481e249..b6c587ec3 100644
--- a/src/main/java/org/traccar/helper/ServletHelper.java
+++ b/src/main/java/org/traccar/helper/ServletHelper.java
@@ -1,8 +1,22 @@
+/*
+ * Copyright 2020 Anton Tananaev (anton@traccar.org)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 package org.traccar.helper;
 
 import javax.servlet.http.HttpServletRequest;
 
-
 public final class ServletHelper {
 
     private ServletHelper() {
@@ -14,10 +28,14 @@ public final class ServletHelper {
             String remoteAddress = request.getHeader("X-FORWARDED-FOR");
 
             if (remoteAddress != null && !remoteAddress.isEmpty()) {
-                return remoteAddress.substring(0, remoteAddress.indexOf(",")); // removes the additional data
+                int separatorIndex = remoteAddress.indexOf(",");
+                if (separatorIndex > 0) {
+                    return remoteAddress.substring(0, separatorIndex); // remove the additional data
+                } else {
+                    return remoteAddress;
+                }
             } else {
-                remoteAddress = request.getRemoteAddr();
-                return remoteAddress;
+                return request.getRemoteAddr();
             }
         } else {
             return null;
diff --git a/src/main/java/org/traccar/notification/NotificatorManager.java b/src/main/java/org/traccar/notification/NotificatorManager.java
index 191748379..c5f1ad8a0 100644
--- a/src/main/java/org/traccar/notification/NotificatorManager.java
+++ b/src/main/java/org/traccar/notification/NotificatorManager.java
@@ -32,6 +32,7 @@ import org.traccar.notificators.Notificator;
 import org.traccar.notificators.NotificatorSms;
 import org.traccar.notificators.NotificatorWeb;
 import org.traccar.notificators.NotificatorTelegram;
+import org.traccar.notificators.NotificatorPushover;
 
 public final class NotificatorManager {
 
@@ -61,6 +62,9 @@ public final class NotificatorManager {
                 case "telegram":
                     defaultNotificator = NotificatorTelegram.class.getCanonicalName();
                     break;
+                case "pushover":
+                    defaultNotificator = NotificatorPushover.class.getCanonicalName();
+                    break;
                 default:
                     break;
             }
diff --git a/src/main/java/org/traccar/notificators/NotificatorPushover.java b/src/main/java/org/traccar/notificators/NotificatorPushover.java
new file mode 100644
index 000000000..141d652ca
--- /dev/null
+++ b/src/main/java/org/traccar/notificators/NotificatorPushover.java
@@ -0,0 +1,100 @@
+/*
+ * Copyright 2020 Anton Tananaev (anton@traccar.org)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.traccar.notificators;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.traccar.Context;
+import org.traccar.model.Event;
+import org.traccar.model.Position;
+import org.traccar.model.User;
+import org.traccar.notification.NotificationFormatter;
+
+import javax.ws.rs.client.Entity;
+import javax.ws.rs.client.InvocationCallback;
+
+public class NotificatorPushover extends Notificator {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(NotificatorPushover.class);
+
+    private final String url;
+    private final String token;
+    private final String puser;
+
+    public static class Message {
+        @JsonProperty("token")
+        private String token;
+        @JsonProperty("user")
+        private String user;
+        @JsonProperty("device")
+        private String device;
+        @JsonProperty("message")
+        private String message;
+    }
+
+    public NotificatorPushover() {
+        url = "https://api.pushover.net/1/messages.json";
+        token = Context.getConfig().getString("notificator.pushover.token");
+        puser = Context.getConfig().getString("notificator.pushover.user");
+    }
+
+    @Override
+    public void sendSync(long userId, Event event, Position position) {
+
+        final User user = Context.getPermissionsManager().getUser(userId);
+
+        String device = "";
+
+        if (user.getAttributes().containsKey("notificator.pushover.device")) {
+            device = user.getString("notificator.pushover.device").replaceAll(" *, *", ",");
+        }
+
+        if (token == null) {
+            LOGGER.warn("Pushover token not found");
+            return;
+        }
+
+        if (puser == null) {
+            LOGGER.warn("Pushover user not found");
+            return;
+        }
+
+        Message message = new Message();
+        message.token = token;
+        message.user = puser;
+        message.device = device;
+        message.message = NotificationFormatter.formatShortMessage(userId, event, position);
+
+        Context.getClient().target(url).request()
+                .async().post(Entity.json(message), new InvocationCallback<Object>() {
+            @Override
+            public void completed(Object o) {
+            }
+
+            @Override
+            public void failed(Throwable throwable) {
+                LOGGER.warn("Pushover API error", throwable);
+            }
+        });
+    }
+
+    @Override
+    public void sendAsync(long userId, Event event, Position position) {
+        sendSync(userId, event, position);
+    }
+
+}
diff --git a/src/main/java/org/traccar/protocol/ArnaviBinaryProtocolDecoder.java b/src/main/java/org/traccar/protocol/ArnaviBinaryProtocolDecoder.java
new file mode 100644
index 000000000..e957a6911
--- /dev/null
+++ b/src/main/java/org/traccar/protocol/ArnaviBinaryProtocolDecoder.java
@@ -0,0 +1,179 @@
+/*
+ * Copyright 2020 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 Ivan Muratov (binakot@gmail.com)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.traccar.protocol;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
+import io.netty.channel.Channel;
+import org.traccar.BaseProtocolDecoder;
+import org.traccar.DeviceSession;
+import org.traccar.NetworkMessage;
+import org.traccar.Protocol;
+import org.traccar.helper.Checksum;
+import org.traccar.model.Position;
+
+import java.net.SocketAddress;
+import java.nio.Buffer;
+import java.nio.ByteBuffer;
+import java.util.Date;
+import java.util.LinkedList;
+import java.util.List;
+
+public class ArnaviBinaryProtocolDecoder extends BaseProtocolDecoder {
+
+    private static final byte HEADER_START_SIGN = (byte) 0xff;
+    private static final byte HEADER_VERSION_1 = 0x22;
+    private static final byte HEADER_VERSION_2 = 0x23;
+
+    private static final byte RECORD_PING = 0x00;
+    private static final byte RECORD_DATA = 0x01;
+    private static final byte RECORD_TEXT = 0x03;
+    private static final byte RECORD_FILE = 0x04;
+    private static final byte RECORD_BINARY = 0x06;
+
+    private static final byte TAG_LATITUDE = 3;
+    private static final byte TAG_LONGITUDE = 4;
+    private static final byte TAG_COORD_PARAMS = 5;
+
+    public ArnaviBinaryProtocolDecoder(Protocol protocol) {
+        super(protocol);
+    }
+
+    private void sendResponse(Channel channel, byte version, int index) {
+        if (channel != null) {
+            ByteBuf response = Unpooled.buffer();
+            response.writeByte(0x7b);
+            if (version == HEADER_VERSION_1) {
+                response.writeByte(0x00);
+                response.writeByte((byte) index);
+            } else if (version == HEADER_VERSION_2) {
+                response.writeByte(0x04);
+                response.writeByte(0x00);
+                ByteBuffer time = ByteBuffer.allocate(4).putInt((int) (System.currentTimeMillis() / 1000));
+                ((Buffer) time).position(0);
+                response.writeByte(Checksum.modulo256(time.slice()));
+                response.writeBytes(time);
+            }
+            response.writeByte(0x7d);
+            channel.writeAndFlush(new NetworkMessage(response, channel.remoteAddress()));
+        }
+    }
+
+    private Position decodePosition(DeviceSession deviceSession, ByteBuf buf, int length, Date time) {
+
+        final Position position = new Position();
+        position.setProtocol(getProtocolName());
+        position.setDeviceId(deviceSession.getDeviceId());
+
+        position.setTime(time);
+
+        int readBytes = 0;
+        while (readBytes < length) {
+            short tag = buf.readUnsignedByte();
+            switch (tag) {
+                case TAG_LATITUDE:
+                    position.setLatitude(buf.readFloatLE());
+                    position.setValid(true);
+                    break;
+
+                case TAG_LONGITUDE:
+                    position.setLongitude(buf.readFloatLE());
+                    position.setValid(true);
+                    break;
+
+                case TAG_COORD_PARAMS:
+                    position.setCourse(buf.readUnsignedByte() * 2);
+                    position.setAltitude(buf.readUnsignedByte() * 10);
+                    byte satellites = buf.readByte();
+                    position.set(Position.KEY_SATELLITES, satellites & 0x0F + (satellites >> 4) & 0x0F);
+                    position.setSpeed(buf.readUnsignedByte());
+                    break;
+
+                default:
+                    buf.skipBytes(4);
+                    break;
+            }
+
+            readBytes += 1 + 4;
+        }
+
+        return position;
+    }
+
+    @Override
+    protected Object decode(Channel channel, SocketAddress remoteAddress, Object msg) throws Exception {
+
+        ByteBuf buf = (ByteBuf) msg;
+
+        byte startSign = buf.readByte();
+
+        if (startSign == HEADER_START_SIGN) {
+
+            byte version = buf.readByte();
+
+            String imei = String.valueOf(buf.readLongLE());
+            DeviceSession deviceSession = getDeviceSession(channel, remoteAddress, imei);
+
+            if (deviceSession != null) {
+                sendResponse(channel, version, 0);
+            }
+
+            return null;
+        }
+
+        DeviceSession deviceSession = getDeviceSession(channel, remoteAddress);
+        if (deviceSession == null) {
+            return null;
+        }
+
+        List<Position> positions = new LinkedList<>();
+
+        int index = buf.readUnsignedByte();
+
+        byte recordType = buf.readByte();
+        while (buf.readableBytes() > 0) {
+            switch (recordType) {
+                case RECORD_PING:
+                case RECORD_DATA:
+                case RECORD_TEXT:
+                case RECORD_FILE:
+                case RECORD_BINARY:
+                    int length = buf.readUnsignedShortLE();
+                    Date time = new Date(buf.readUnsignedIntLE() * 1000);
+
+                    if (recordType == RECORD_DATA) {
+                        positions.add(decodePosition(deviceSession, buf, length, time));
+                    } else {
+                        buf.readBytes(length);
+                    }
+
+                    buf.readUnsignedByte(); // checksum
+                    break;
+
+                default:
+                    return null;
+            }
+
+            recordType = buf.readByte();
+        }
+
+        sendResponse(channel, HEADER_VERSION_1, index);
+
+        return positions;
+    }
+
+}
diff --git a/src/main/java/org/traccar/protocol/ArnaviFrameDecoder.java b/src/main/java/org/traccar/protocol/ArnaviFrameDecoder.java
new file mode 100644
index 000000000..473e8b2c7
--- /dev/null
+++ b/src/main/java/org/traccar/protocol/ArnaviFrameDecoder.java
@@ -0,0 +1,82 @@
+/*
+ * Copyright 2020 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 Ivan Muratov (binakot@gmail.com)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.traccar.protocol;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.Channel;
+import io.netty.channel.ChannelHandlerContext;
+import org.traccar.BaseFrameDecoder;
+import org.traccar.helper.BufferUtil;
+
+public class ArnaviFrameDecoder extends BaseFrameDecoder {
+
+    private static final int HEADER_LENGTH = 10;
+    private static final int PACKET_WRAPPER_LENGTH = 8;
+    private static final int RESULT_TYPE = 0xfd;
+    private static final byte PACKAGE_END_SIGN = 0x5d;
+
+    private boolean firstPacket = true;
+
+    @Override
+    protected Object decode(ChannelHandlerContext ctx, Channel channel, ByteBuf buf) throws Exception {
+
+        if (buf.readableBytes() < 4) {
+            return null;
+        }
+
+        if (buf.getByte(buf.readerIndex()) == '$') {
+
+            int index = BufferUtil.indexOf("\r\n", buf);
+            if (index > 0) {
+                ByteBuf frame = buf.readRetainedSlice(index - buf.readerIndex());
+                buf.skipBytes(2);
+                return frame;
+            }
+
+        } else {
+
+            int length;
+            if (firstPacket) {
+                firstPacket = false;
+                length = HEADER_LENGTH;
+            } else {
+                int type = buf.getUnsignedByte(1);
+                if (type == RESULT_TYPE) {
+                    length = 4;
+                } else {
+                    int index = 2;
+                    while (index + PACKET_WRAPPER_LENGTH < buf.readableBytes()
+                            && buf.getByte(index) != PACKAGE_END_SIGN) {
+                        index += PACKET_WRAPPER_LENGTH + buf.getUnsignedShortLE(index + 1);
+                    }
+                    if (buf.getByte(index) != PACKAGE_END_SIGN) {
+                        return null;
+                    }
+                    length = index + 1;
+                }
+            }
+
+            if (buf.readableBytes() >= length) {
+                return buf.readRetainedSlice(length);
+            }
+
+        }
+
+        return null;
+    }
+
+}
diff --git a/src/main/java/org/traccar/protocol/ArnaviProtocol.java b/src/main/java/org/traccar/protocol/ArnaviProtocol.java
index afe491865..aecb42c8c 100644
--- a/src/main/java/org/traccar/protocol/ArnaviProtocol.java
+++ b/src/main/java/org/traccar/protocol/ArnaviProtocol.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 - 2018 Anton Tananaev (anton@traccar.org)
+ * Copyright 2015 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,9 +15,6 @@
  */
 package org.traccar.protocol;
 
-import io.netty.handler.codec.LineBasedFrameDecoder;
-import io.netty.handler.codec.string.StringDecoder;
-import io.netty.handler.codec.string.StringEncoder;
 import org.traccar.BaseProtocol;
 import org.traccar.PipelineBuilder;
 import org.traccar.TrackerServer;
@@ -28,9 +25,7 @@ public class ArnaviProtocol extends BaseProtocol {
         addServer(new TrackerServer(false, getName()) {
             @Override
             protected void addProtocolHandlers(PipelineBuilder pipeline) {
-                pipeline.addLast(new LineBasedFrameDecoder(1024));
-                pipeline.addLast(new StringDecoder());
-                pipeline.addLast(new StringEncoder());
+                pipeline.addLast(new ArnaviFrameDecoder());
                 pipeline.addLast(new ArnaviProtocolDecoder(ArnaviProtocol.this));
             }
         });
diff --git a/src/main/java/org/traccar/protocol/ArnaviProtocolDecoder.java b/src/main/java/org/traccar/protocol/ArnaviProtocolDecoder.java
index 7996cf429..68a70c944 100644
--- a/src/main/java/org/traccar/protocol/ArnaviProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/ArnaviProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 - 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,91 +15,35 @@
  */
 package org.traccar.protocol;
 
+import io.netty.buffer.ByteBuf;
 import io.netty.channel.Channel;
 import org.traccar.BaseProtocolDecoder;
-import org.traccar.DeviceSession;
 import org.traccar.Protocol;
-import org.traccar.helper.DateBuilder;
-import org.traccar.helper.Parser;
-import org.traccar.helper.PatternBuilder;
-import org.traccar.model.Position;
 
 import java.net.SocketAddress;
-import java.util.regex.Pattern;
 
 public class ArnaviProtocolDecoder extends BaseProtocolDecoder {
 
+    private final ArnaviTextProtocolDecoder textProtocolDecoder;
+    private final ArnaviBinaryProtocolDecoder binaryProtocolDecoder;
+
     public ArnaviProtocolDecoder(Protocol protocol) {
         super(protocol);
+        textProtocolDecoder = new ArnaviTextProtocolDecoder(protocol);
+        binaryProtocolDecoder = new ArnaviBinaryProtocolDecoder(protocol);
     }
 
-    private static final Pattern PATTERN = new PatternBuilder()
-            .text("$AV,")
-            .number("Vd,")                       // type
-            .number("(d+),")                     // device id
-            .number("(d+),")                     // index
-            .number("(d+),")                     // power
-            .number("(d+),")                     // battery
-            .number("-?d+,")
-            .expression("[01],")                 // movement
-            .expression("([01]),")               // ignition
-            .number("(d+),")                     // input
-            .number("d+,d+,")                    // input 1
-            .number("d+,d+,").optional()         // input 2
-            .expression("[01],")                 // fix type
-            .number("(d+),")                     // satellites
-            .groupBegin()
-            .number("(d+.d+)?,")                 // altitude
-            .number("(?:d+.d+)?,")               // geoid height
-            .groupEnd("?")
-            .number("(dd)(dd)(dd),")             // time (hhmmss)
-            .number("(dd)(dd.d+)([NS]),")        // latitude
-            .number("(ddd)(dd.d+)([EW]),")       // longitude
-            .number("(d+.d+),")                  // speed
-            .number("(d+.d+),")                  // course
-            .number("(dd)(dd)(dd)")              // date (ddmmyy)
-            .any()
-            .compile();
-
     @Override
     protected Object decode(
             Channel channel, SocketAddress remoteAddress, Object msg) throws Exception {
 
-        Parser parser = new Parser(PATTERN, (String) msg);
-        if (!parser.matches()) {
-            return null;
-        }
+        ByteBuf buf = (ByteBuf) msg;
 
-        Position position = new Position(getProtocolName());
-
-        DeviceSession deviceSession = getDeviceSession(channel, remoteAddress, parser.next());
-        if (deviceSession == null) {
-            return null;
+        if (buf.getByte(buf.readerIndex()) == '$') {
+            return textProtocolDecoder.decode(channel, remoteAddress, msg);
+        } else {
+            return binaryProtocolDecoder.decode(channel, remoteAddress, msg);
         }
-        position.setDeviceId(deviceSession.getDeviceId());
-
-        position.set(Position.KEY_INDEX, parser.nextInt());
-        position.set(Position.KEY_POWER, parser.nextInt() * 0.01);
-        position.set(Position.KEY_BATTERY, parser.nextInt() * 0.01);
-        position.set(Position.KEY_IGNITION, parser.nextInt() == 1);
-        position.set(Position.KEY_INPUT, parser.nextInt());
-        position.set(Position.KEY_SATELLITES, parser.nextInt());
-
-        position.setAltitude(parser.nextDouble(0));
-
-        DateBuilder dateBuilder = new DateBuilder()
-                .setTime(parser.nextInt(), parser.nextInt(), parser.nextInt());
-
-        position.setValid(true);
-        position.setLatitude(parser.nextCoordinate());
-        position.setLongitude(parser.nextCoordinate());
-        position.setSpeed(parser.nextDouble());
-        position.setCourse(parser.nextDouble());
-
-        dateBuilder.setDateReverse(parser.nextInt(), parser.nextInt(), parser.nextInt());
-        position.setTime(dateBuilder.getDate());
-
-        return position;
     }
 
 }
diff --git a/src/main/java/org/traccar/protocol/ArnaviTextProtocolDecoder.java b/src/main/java/org/traccar/protocol/ArnaviTextProtocolDecoder.java
new file mode 100644
index 000000000..b99869e6e
--- /dev/null
+++ b/src/main/java/org/traccar/protocol/ArnaviTextProtocolDecoder.java
@@ -0,0 +1,108 @@
+/*
+ * Copyright 2015 - 2020 Anton Tananaev (anton@traccar.org)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.traccar.protocol;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.Channel;
+import org.traccar.BaseProtocolDecoder;
+import org.traccar.DeviceSession;
+import org.traccar.Protocol;
+import org.traccar.helper.DateBuilder;
+import org.traccar.helper.Parser;
+import org.traccar.helper.PatternBuilder;
+import org.traccar.model.Position;
+
+import java.net.SocketAddress;
+import java.nio.charset.StandardCharsets;
+import java.util.regex.Pattern;
+
+public class ArnaviTextProtocolDecoder extends BaseProtocolDecoder {
+
+    public ArnaviTextProtocolDecoder(Protocol protocol) {
+        super(protocol);
+    }
+
+    private static final Pattern PATTERN = new PatternBuilder()
+            .text("$AV,")
+            .number("Vd,")                       // type
+            .number("(d+),")                     // device id
+            .number("(d+),")                     // index
+            .number("(d+),")                     // power
+            .number("(d+),")                     // battery
+            .number("-?d+,")
+            .expression("[01],")                 // movement
+            .expression("([01]),")               // ignition
+            .number("(d+),")                     // input
+            .number("d+,d+,")                    // input 1
+            .number("d+,d+,").optional()         // input 2
+            .expression("[01],")                 // fix type
+            .number("(d+),")                     // satellites
+            .groupBegin()
+            .number("(d+.d+)?,")                 // altitude
+            .number("(?:d+.d+)?,")               // geoid height
+            .groupEnd("?")
+            .number("(dd)(dd)(dd),")             // time (hhmmss)
+            .number("(dd)(dd.d+)([NS]),")        // latitude
+            .number("(ddd)(dd.d+)([EW]),")       // longitude
+            .number("(d+.d+),")                  // speed
+            .number("(d+.d+),")                  // course
+            .number("(dd)(dd)(dd)")              // date (ddmmyy)
+            .any()
+            .compile();
+
+    @Override
+    protected Object decode(
+            Channel channel, SocketAddress remoteAddress, Object msg) throws Exception {
+
+        ByteBuf buf = (ByteBuf) msg;
+        Parser parser = new Parser(PATTERN, buf.toString(StandardCharsets.US_ASCII));
+        if (!parser.matches()) {
+            return null;
+        }
+
+        Position position = new Position(getProtocolName());
+
+        DeviceSession deviceSession = getDeviceSession(channel, remoteAddress, parser.next());
+        if (deviceSession == null) {
+            return null;
+        }
+        position.setDeviceId(deviceSession.getDeviceId());
+
+        position.set(Position.KEY_INDEX, parser.nextInt());
+        position.set(Position.KEY_POWER, parser.nextInt() * 0.01);
+        position.set(Position.KEY_BATTERY, parser.nextInt() * 0.01);
+        position.set(Position.KEY_IGNITION, parser.nextInt() == 1);
+        position.set(Position.KEY_INPUT, parser.nextInt());
+        position.set(Position.KEY_SATELLITES, parser.nextInt());
+
+        position.setAltitude(parser.nextDouble(0));
+
+        DateBuilder dateBuilder = new DateBuilder()
+                .setTime(parser.nextInt(), parser.nextInt(), parser.nextInt());
+
+        position.setValid(true);
+        position.setLatitude(parser.nextCoordinate());
+        position.setLongitude(parser.nextCoordinate());
+        position.setSpeed(parser.nextDouble());
+        position.setCourse(parser.nextDouble());
+
+        dateBuilder.setDateReverse(parser.nextInt(), parser.nextInt(), parser.nextInt());
+        position.setTime(dateBuilder.getDate());
+
+        return position;
+    }
+
+}
diff --git a/src/main/java/org/traccar/protocol/BceProtocolDecoder.java b/src/main/java/org/traccar/protocol/BceProtocolDecoder.java
index 30f9bb1f3..a259e027a 100644
--- a/src/main/java/org/traccar/protocol/BceProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/BceProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 - 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2015 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -83,10 +83,10 @@ public class BceProtocolDecoder extends BaseProtocolDecoder {
             buf.skipBytes(4);
         }
         if (BitUtil.check(mask, 12)) {
-            buf.skipBytes(2);
+            position.set("fuel1", buf.readUnsignedShort());
         }
         if (BitUtil.check(mask, 13)) {
-            buf.skipBytes(2);
+            position.set("fuel2", buf.readUnsignedShort());
         }
 
         if (BitUtil.check(mask, 14)) {
@@ -113,7 +113,7 @@ public class BceProtocolDecoder extends BaseProtocolDecoder {
             position.set(Position.KEY_FUEL_LEVEL, buf.readUnsignedByte());
         }
         if (BitUtil.check(mask, 4)) {
-            position.set(Position.KEY_RPM, buf.readUnsignedShortLE());
+            position.set(Position.KEY_RPM, buf.readUnsignedShortLE() * 0.125);
         }
         if (BitUtil.check(mask, 5)) {
             position.set(Position.KEY_HOURS, buf.readUnsignedIntLE());
@@ -122,7 +122,7 @@ public class BceProtocolDecoder extends BaseProtocolDecoder {
             position.set(Position.KEY_ODOMETER, buf.readUnsignedIntLE());
         }
         if (BitUtil.check(mask, 7)) {
-            position.set(Position.KEY_COOLANT_TEMP, (int) buf.readByte());
+            position.set(Position.KEY_COOLANT_TEMP, buf.readByte() - 40);
         }
         if (BitUtil.check(mask, 8)) {
             position.set("fuel2", buf.readUnsignedByte());
@@ -217,9 +217,9 @@ public class BceProtocolDecoder extends BaseProtocolDecoder {
             buf.readUnsignedShortLE();
         }
         if (BitUtil.check(mask, 6)) {
-            buf.readUnsignedByte(); // maximum acceleration
-            buf.readUnsignedByte(); // maximum deceleration
-            buf.readUnsignedByte(); // maximum cornering
+            position.set("maxAcceleration", buf.readUnsignedByte() * 0.02);
+            position.set("maxBraking", buf.readUnsignedByte() * 0.02);
+            position.set("maxCornering", buf.readUnsignedByte() * 0.02);
         }
         if (BitUtil.check(mask, 7)) {
             buf.skipBytes(16);
diff --git a/src/main/java/org/traccar/protocol/BlueProtocol.java b/src/main/java/org/traccar/protocol/BlueProtocol.java
index 79f0714ec..d5dc5c421 100644
--- a/src/main/java/org/traccar/protocol/BlueProtocol.java
+++ b/src/main/java/org/traccar/protocol/BlueProtocol.java
@@ -26,7 +26,7 @@ public class BlueProtocol extends BaseProtocol {
         addServer(new TrackerServer(false, getName()) {
             @Override
             protected void addProtocolHandlers(PipelineBuilder pipeline) {
-                pipeline.addLast(new LengthFieldBasedFrameDecoder(1024, 1, 2, 3, 0));
+                pipeline.addLast(new LengthFieldBasedFrameDecoder(1024, 1, 2, -2, 0));
                 pipeline.addLast(new BlueProtocolDecoder(BlueProtocol.this));
             }
         });
diff --git a/src/main/java/org/traccar/protocol/BlueProtocolDecoder.java b/src/main/java/org/traccar/protocol/BlueProtocolDecoder.java
index 98a8ae565..f35ac6fbe 100644
--- a/src/main/java/org/traccar/protocol/BlueProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/BlueProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2019 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,11 +16,14 @@
 package org.traccar.protocol;
 
 import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
 import io.netty.channel.Channel;
 import org.traccar.BaseProtocolDecoder;
 import org.traccar.DeviceSession;
+import org.traccar.NetworkMessage;
 import org.traccar.Protocol;
 import org.traccar.helper.BitUtil;
+import org.traccar.helper.Checksum;
 import org.traccar.helper.DateBuilder;
 import org.traccar.model.Position;
 
@@ -41,6 +44,41 @@ public class BlueProtocolDecoder extends BaseProtocolDecoder {
         return negative ? -coordinate : coordinate;
     }
 
+    private void sendResponse(Channel channel, int deviceIndex) {
+        if (channel != null) {
+
+            ByteBuf response = Unpooled.buffer();
+            response.writeByte(0xaa);
+            response.writeShort(2 + 1 + 1 + 6 + 1);
+            response.writeByte(0x86); // version
+            response.writeByte(0);
+
+            response.writeByte(6); // data length
+            response.writeByte(0xa4); // type
+            response.writeByte(0); // server index
+            response.writeByte(deviceIndex);
+            response.writeByte(0);
+            response.writeByte(0);
+
+            response.writeByte(Checksum.xor(response.nioBuffer(1, response.writerIndex() - 1)));
+
+            channel.writeAndFlush(new NetworkMessage(response, channel.remoteAddress()));
+        }
+    }
+
+    private String decodeAlarm(int value) {
+        switch (value) {
+            case 1:
+                return Position.ALARM_SOS;
+            case 8:
+                return Position.ALARM_OVERSPEED;
+            case 19:
+                return Position.ALARM_LOW_POWER;
+            default:
+                return null;
+        }
+    }
+
     @Override
     protected Object decode(
             Channel channel, SocketAddress remoteAddress, Object msg) throws Exception {
@@ -66,7 +104,7 @@ public class BlueProtocolDecoder extends BaseProtocolDecoder {
             int frameEnd = buf.readerIndex() + buf.readUnsignedByte();
 
             int type = buf.readUnsignedByte();
-            buf.readUnsignedByte(); // reference id
+            int index = buf.readUnsignedByte();
             buf.readUnsignedByte();
             buf.readUnsignedByte(); // flags
 
@@ -98,10 +136,29 @@ public class BlueProtocolDecoder extends BaseProtocolDecoder {
 
                 buf.readUnsignedByte(); // status 2
                 buf.readUnsignedByte(); // status 3
-                buf.readUnsignedByte(); // status 4
+
+                status = buf.readUnsignedByte(); // status 4
+                int ignition = BitUtil.between(status, 2, 4);
+                if (ignition == 0b01) {
+                    position.set(Position.KEY_IGNITION, false);
+                }
+                if (ignition == 0b10) {
+                    position.set(Position.KEY_IGNITION, true);
+                }
+
                 buf.readUnsignedByte(); // status 5
                 buf.readUnsignedByte(); // status 6
 
+                position.set(Position.KEY_STATUS, buf.readUnsignedShort());
+
+            } else if (type == 0x81) {
+
+                position.set(Position.KEY_ALARM, decodeAlarm(buf.readUnsignedByte()));
+
+            } else if (type == 0x84) {
+
+                sendResponse(channel, index);
+
             }
 
             buf.readerIndex(frameEnd);
diff --git a/src/main/java/org/traccar/protocol/EskyProtocol.java b/src/main/java/org/traccar/protocol/EskyProtocol.java
index aaa92da58..fb047c207 100644
--- a/src/main/java/org/traccar/protocol/EskyProtocol.java
+++ b/src/main/java/org/traccar/protocol/EskyProtocol.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 - 2018 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -33,6 +33,14 @@ public class EskyProtocol extends BaseProtocol {
                 pipeline.addLast(new EskyProtocolDecoder(EskyProtocol.this));
             }
         });
+        addServer(new TrackerServer(true, getName()) {
+            @Override
+            protected void addProtocolHandlers(PipelineBuilder pipeline) {
+                pipeline.addLast(new StringEncoder());
+                pipeline.addLast(new StringDecoder());
+                pipeline.addLast(new EskyProtocolDecoder(EskyProtocol.this));
+            }
+        });
     }
 
 }
diff --git a/src/main/java/org/traccar/protocol/EskyProtocolDecoder.java b/src/main/java/org/traccar/protocol/EskyProtocolDecoder.java
index 641b2e28f..1a4f9b906 100644
--- a/src/main/java/org/traccar/protocol/EskyProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/EskyProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 - 2018 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,9 +16,12 @@
 package org.traccar.protocol;
 
 import io.netty.channel.Channel;
+import io.netty.channel.socket.DatagramChannel;
 import org.traccar.BaseProtocolDecoder;
 import org.traccar.DeviceSession;
+import org.traccar.NetworkMessage;
 import org.traccar.Protocol;
+import org.traccar.helper.BitUtil;
 import org.traccar.helper.Parser;
 import org.traccar.helper.PatternBuilder;
 import org.traccar.helper.UnitsConverter;
@@ -35,7 +38,7 @@ public class EskyProtocolDecoder extends BaseProtocolDecoder {
 
     private static final Pattern PATTERN = new PatternBuilder()
             .expression("..;")                   // header
-            .number("d+;")                       // index
+            .number("d+;")
             .number("(d+);")                     // imei
             .text("R;")                          // data type
             .number("(d+)[+;]")                  // satellites
@@ -58,7 +61,8 @@ public class EskyProtocolDecoder extends BaseProtocolDecoder {
     protected Object decode(
             Channel channel, SocketAddress remoteAddress, Object msg) throws Exception {
 
-        Parser parser = new Parser(PATTERN, (String) msg);
+        String sentence = (String) msg;
+        Parser parser = new Parser(PATTERN, sentence);
         if (!parser.matches()) {
             return null;
         }
@@ -81,13 +85,21 @@ public class EskyProtocolDecoder extends BaseProtocolDecoder {
         position.setCourse(parser.nextDouble());
 
         if (parser.hasNext(3)) {
-            position.set(Position.KEY_INPUT, parser.nextHexInt());
+            int input = parser.nextHexInt();
+            position.set(Position.KEY_IGNITION, !BitUtil.check(input, 0));
+            position.set(Position.PREFIX_IN + 1, !BitUtil.check(input, 1));
+            position.set(Position.PREFIX_IN + 2, !BitUtil.check(input, 2));
             position.set(Position.KEY_EVENT, parser.nextInt());
             position.set(Position.KEY_ODOMETER, parser.nextInt());
         }
 
         position.set(Position.KEY_BATTERY, parser.nextInt() * 0.001);
 
+        int index = sentence.lastIndexOf('+');
+        if (index > 0 && channel instanceof DatagramChannel) {
+            channel.writeAndFlush(new NetworkMessage("ACK," + sentence.substring(index + 1) + "#", remoteAddress));
+        }
+
         return position;
     }
 
diff --git a/src/main/java/org/traccar/protocol/FifotrackProtocolDecoder.java b/src/main/java/org/traccar/protocol/FifotrackProtocolDecoder.java
index 40e146e0b..9bc7cb504 100644
--- a/src/main/java/org/traccar/protocol/FifotrackProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/FifotrackProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016 - 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2016 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -116,6 +116,32 @@ public class FifotrackProtocolDecoder extends BaseProtocolDecoder {
                     return Position.ALARM_POWER_CUT;
                 case 16:
                     return Position.ALARM_POWER_RESTORED;
+                case 17:
+                    return Position.ALARM_LOW_BATTERY;
+                case 18:
+                    return Position.ALARM_OVERSPEED;
+                case 20:
+                    return Position.ALARM_GPS_ANTENNA_CUT;
+                case 21:
+                    return Position.ALARM_VIBRATION;
+                case 23:
+                    return Position.ALARM_ACCELERATION;
+                case 24:
+                    return Position.ALARM_BRAKING;
+                case 27:
+                    return Position.ALARM_FATIGUE_DRIVING;
+                case 30:
+                case 32:
+                    return Position.ALARM_JAMMING;
+                case 33:
+                    return Position.ALARM_GEOFENCE_EXIT;
+                case 34:
+                    return Position.ALARM_GEOFENCE_ENTER;
+                case 35:
+                    return Position.ALARM_IDLE;
+                case 40:
+                case 41:
+                    return Position.ALARM_TEMPERATURE;
                 default:
                     return null;
             }
diff --git a/src/main/java/org/traccar/protocol/GatorProtocolDecoder.java b/src/main/java/org/traccar/protocol/GatorProtocolDecoder.java
index 043839be9..087861635 100644
--- a/src/main/java/org/traccar/protocol/GatorProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/GatorProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013 - 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2013 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,6 +23,7 @@ import org.traccar.DeviceSession;
 import org.traccar.NetworkMessage;
 import org.traccar.Protocol;
 import org.traccar.helper.BcdUtil;
+import org.traccar.helper.Checksum;
 import org.traccar.helper.DateBuilder;
 import org.traccar.helper.UnitsConverter;
 import org.traccar.model.Position;
@@ -58,16 +59,16 @@ public class GatorProtocolDecoder extends BaseProtocolDecoder {
         return String.format("%02d%02d%02d%02d%02d", d1, d2, d3, d4, d5);
     }
 
-    private void sendResponse(Channel channel, SocketAddress remoteAddress, byte calibration) {
+    private void sendResponse(Channel channel, SocketAddress remoteAddress, int type, int checksum) {
         if (channel != null) {
             ByteBuf response = Unpooled.buffer();
-            response.writeByte(0x24); response.writeByte(0x24); // header
-            response.writeByte(MSG_HEARTBEAT); // size
-            response.writeShort(5);
-            response.writeByte(calibration);
-            response.writeByte(0); // main order
-            response.writeByte(0); // slave order
-            response.writeByte(1); // calibration
+            response.writeShort(0x2424); // header
+            response.writeByte(MSG_HEARTBEAT);
+            response.writeShort(5); // length
+            response.writeByte(checksum);
+            response.writeByte(type);
+            response.writeByte(0); // subtype
+            response.writeByte(Checksum.xor(response.nioBuffer(2, response.writerIndex())));
             response.writeByte(0x0D);
             channel.writeAndFlush(new NetworkMessage(response, remoteAddress));
         }
@@ -87,7 +88,7 @@ public class GatorProtocolDecoder extends BaseProtocolDecoder {
                 buf.readUnsignedByte(), buf.readUnsignedByte(),
                 buf.readUnsignedByte(), buf.readUnsignedByte());
 
-        sendResponse(channel, remoteAddress, buf.getByte(buf.writerIndex() - 2));
+        sendResponse(channel, remoteAddress, type, buf.getByte(buf.writerIndex() - 2));
 
         if (type == MSG_POSITION_DATA || type == MSG_ROLLCALL_RESPONSE
                 || type == MSG_ALARM_DATA || type == MSG_BLIND_AREA) {
diff --git a/src/main/java/org/traccar/protocol/GlobalstarProtocolDecoder.java b/src/main/java/org/traccar/protocol/GlobalstarProtocolDecoder.java
index 26af8d5af..ab89f10c8 100644
--- a/src/main/java/org/traccar/protocol/GlobalstarProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/GlobalstarProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2019 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,6 +23,7 @@ import io.netty.channel.Channel;
 import io.netty.handler.codec.http.DefaultFullHttpResponse;
 import io.netty.handler.codec.http.FullHttpRequest;
 import io.netty.handler.codec.http.FullHttpResponse;
+import io.netty.handler.codec.http.HttpHeaderNames;
 import io.netty.handler.codec.http.HttpResponseStatus;
 import io.netty.handler.codec.http.HttpVersion;
 import org.traccar.BaseHttpProtocolDecoder;
@@ -96,21 +97,23 @@ public class GlobalstarProtocolDecoder extends BaseHttpProtocolDecoder {
         rootElement.appendChild(state);
 
         Element stateMessage = document.createElement("stateMessage");
-        stateMessage.appendChild(document.createTextNode("Messages received and stored successfully"));
+        stateMessage.appendChild(document.createTextNode("Store OK"));
         rootElement.appendChild(stateMessage);
 
         Transformer transformer = TransformerFactory.newInstance().newTransformer();
         ByteBuf content = Unpooled.buffer();
         transformer.transform(new DOMSource(document), new StreamResult(new ByteBufOutputStream(content)));
 
-        FullHttpResponse response = new DefaultFullHttpResponse(
-                HttpVersion.HTTP_1_1, HttpResponseStatus.OK, content);
         if (channel != null) {
+            FullHttpResponse response = new DefaultFullHttpResponse(
+                    HttpVersion.HTTP_1_1, HttpResponseStatus.OK, content);
+            response.headers()
+                    .add(HttpHeaderNames.CONTENT_LENGTH, content.readableBytes())
+                    .add(HttpHeaderNames.CONTENT_TYPE, "text/xml");
             channel.writeAndFlush(new NetworkMessage(response, channel.remoteAddress()));
         }
     }
 
-
     @Override
     protected Object decode(
             Channel channel, SocketAddress remoteAddress, Object msg) throws Exception {
diff --git a/src/main/java/org/traccar/protocol/Gt06ProtocolDecoder.java b/src/main/java/org/traccar/protocol/Gt06ProtocolDecoder.java
index c435b6cec..946652b03 100644
--- a/src/main/java/org/traccar/protocol/Gt06ProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/Gt06ProtocolDecoder.java
@@ -730,6 +730,14 @@ public class Gt06ProtocolDecoder extends BaseProtocolDecoder {
                 decodeStatus(position, buf);
             }
 
+            if (type == MSG_GPS_LBS_1 && buf.readableBytes() > 75 + 6) {
+                position.set(Position.KEY_ODOMETER, buf.readUnsignedInt());
+                String data = buf.readCharSequence(buf.readUnsignedByte(), StandardCharsets.US_ASCII).toString();
+                buf.readUnsignedByte(); // alarm
+                buf.readUnsignedByte(); // swiped
+                position.set("driverLicense", data.trim());
+            }
+
             if (type == MSG_GPS_LBS_1 && buf.readableBytes() == 2 + 6) {
                 int mask = buf.readUnsignedShort();
                 position.set(Position.KEY_IGNITION, BitUtil.check(mask, 8 + 7));
diff --git a/src/main/java/org/traccar/protocol/HuaShengProtocolDecoder.java b/src/main/java/org/traccar/protocol/HuaShengProtocolDecoder.java
index 9449e2d5c..eac06bbfe 100644
--- a/src/main/java/org/traccar/protocol/HuaShengProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/HuaShengProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016 - 2018 Anton Tananaev (anton@traccar.org)
+ * Copyright 2016 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -25,7 +25,10 @@ import org.traccar.Protocol;
 import org.traccar.helper.BitUtil;
 import org.traccar.helper.DateBuilder;
 import org.traccar.helper.UnitsConverter;
+import org.traccar.model.CellTower;
+import org.traccar.model.Network;
 import org.traccar.model.Position;
+import org.traccar.model.WifiAccessPoint;
 
 import java.net.SocketAddress;
 import java.nio.charset.StandardCharsets;
@@ -137,6 +140,8 @@ public class HuaShengProtocolDecoder extends BaseProtocolDecoder {
 
             position.set(Position.KEY_ODOMETER, buf.readUnsignedShort() * 1000);
 
+            Network network = new Network();
+
             while (buf.readableBytes() > 4) {
                 int subtype = buf.readUnsignedShort();
                 int length = buf.readUnsignedShort() - 4;
@@ -161,12 +166,34 @@ public class HuaShengProtocolDecoder extends BaseProtocolDecoder {
                         position.set(
                                 Position.KEY_VIN, buf.readCharSequence(length, StandardCharsets.US_ASCII).toString());
                         break;
+                    case 0x0020:
+                        String[] cells = buf.readCharSequence(
+                                length, StandardCharsets.US_ASCII).toString().split("\\+");
+                        for (String cell : cells) {
+                            String[] values = cell.split("@");
+                            network.addCellTower(CellTower.from(
+                                    Integer.parseInt(values[0]), Integer.parseInt(values[1]),
+                                    Integer.parseInt(values[2], 16), Integer.parseInt(values[3], 16)));
+                        }
+                        break;
+                    case 0x0021:
+                        String[] points = buf.readCharSequence(
+                                length, StandardCharsets.US_ASCII).toString().split("\\+");
+                        for (String point : points) {
+                            String[] values = point.split("@");
+                            network.addWifiAccessPoint(WifiAccessPoint.from(values[0], Integer.parseInt(values[1])));
+                        }
+                        break;
                     default:
                         buf.skipBytes(length);
                         break;
                 }
             }
 
+            if (network.getCellTowers() != null || network.getWifiAccessPoints() != null) {
+                position.setNetwork(network);
+            }
+
             sendResponse(channel, MSG_POSITION_RSP, index, null);
 
             return position;
diff --git a/src/main/java/org/traccar/protocol/ItsProtocolDecoder.java b/src/main/java/org/traccar/protocol/ItsProtocolDecoder.java
index e8d77f1a8..6a107d67d 100644
--- a/src/main/java/org/traccar/protocol/ItsProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/ItsProtocolDecoder.java
@@ -51,7 +51,7 @@ public class ItsProtocolDecoder extends BaseProtocolDecoder {
             .groupEnd()
             .number("(d{15}),")                  // imei
             .groupBegin()
-            .expression("(..),")                 // status
+            .expression("([^,]{2}),")            // status
             .or()
             .expression("[^,]*,")                // vehicle registration
             .number("([01]),").optional()        // valid
diff --git a/src/main/java/org/traccar/protocol/LeafSpyProtocolDecoder.java b/src/main/java/org/traccar/protocol/LeafSpyProtocolDecoder.java
index 5b352a961..ad0c9bd32 100644
--- a/src/main/java/org/traccar/protocol/LeafSpyProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/LeafSpyProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2019 - 2020 Anton Tananaev (anton@traccar.org)
  * Copyright 2019 Jesse Hills (jesserockz@gmail.com)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -19,16 +19,12 @@ package org.traccar.protocol;
 import io.netty.buffer.Unpooled;
 import io.netty.channel.Channel;
 import io.netty.handler.codec.http.FullHttpRequest;
-import io.netty.handler.codec.http.DefaultFullHttpResponse;
-import io.netty.handler.codec.http.HttpResponse;
 import io.netty.handler.codec.http.HttpResponseStatus;
-import io.netty.handler.codec.http.HttpVersion;
 import io.netty.handler.codec.http.QueryStringDecoder;
 import org.traccar.BaseHttpProtocolDecoder;
 import org.traccar.DeviceSession;
 import org.traccar.Protocol;
 import org.traccar.model.Position;
-import org.traccar.NetworkMessage;
 
 import java.net.SocketAddress;
 import java.nio.charset.StandardCharsets;
@@ -122,13 +118,8 @@ public class LeafSpyProtocolDecoder extends BaseHttpProtocolDecoder {
         }
 
         if (position.getDeviceId() != 0) {
-            if (channel != null) {
-                HttpResponse response = new DefaultFullHttpResponse(
-                    HttpVersion.HTTP_1_1,
-                    HttpResponseStatus.OK,
+            sendResponse(channel, HttpResponseStatus.OK,
                     Unpooled.copiedBuffer("\"status\":\"0\"", StandardCharsets.US_ASCII));
-                channel.writeAndFlush(new NetworkMessage(response, channel.remoteAddress()));
-            }
             return position;
         } else {
             sendResponse(channel, HttpResponseStatus.BAD_REQUEST);
diff --git a/src/main/java/org/traccar/protocol/MeiligaoProtocolDecoder.java b/src/main/java/org/traccar/protocol/MeiligaoProtocolDecoder.java
index cbfc3660a..bd66cdc4b 100644
--- a/src/main/java/org/traccar/protocol/MeiligaoProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/MeiligaoProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2012 - 2018 Anton Tananaev (anton@traccar.org)
+ * Copyright 2012 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -47,7 +47,7 @@ public class MeiligaoProtocolDecoder extends BaseProtocolDecoder {
     }
 
     private static final Pattern PATTERN = new PatternBuilder()
-            .number("(dd)(dd)(dd).?d*,")         // time (hhmmss)
+            .number("(d+)(dd)(dd).?d*,")         // time (hhmmss)
             .expression("([AV]),")               // validity
             .number("(d+)(dd.d+),")              // latitude
             .expression("([NS]),")
diff --git a/src/main/java/org/traccar/protocol/MeitrackProtocolDecoder.java b/src/main/java/org/traccar/protocol/MeitrackProtocolDecoder.java
index 55260ef0c..529496928 100644
--- a/src/main/java/org/traccar/protocol/MeitrackProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/MeitrackProtocolDecoder.java
@@ -70,7 +70,8 @@ public class MeitrackProtocolDecoder extends BaseProtocolDecoder {
             .number("(d+)|")                     // mnc
             .number("(x+)|")                     // lac
             .number("(x+),")                     // cid
-            .number("(x+),")                     // state
+            .number("(xx)")                      // input
+            .number("(xx),")                     // output
             .number("(x+)?|")                    // adc1
             .number("(x+)?|")                    // adc2
             .number("(x+)?|")                    // adc3
@@ -149,39 +150,38 @@ public class MeitrackProtocolDecoder extends BaseProtocolDecoder {
         }
         position.setDeviceId(deviceSession.getDeviceId());
 
-        int event = parser.nextInt(0);
+        int event = parser.nextInt();
         position.set(Position.KEY_EVENT, event);
         position.set(Position.KEY_ALARM, decodeAlarm(event));
 
-        position.setLatitude(parser.nextDouble(0));
-        position.setLongitude(parser.nextDouble(0));
+        position.setLatitude(parser.nextDouble());
+        position.setLongitude(parser.nextDouble());
 
         position.setTime(parser.nextDateTime());
 
         position.setValid(parser.next().equals("A"));
 
         position.set(Position.KEY_SATELLITES, parser.nextInt());
-        int rssi = parser.nextInt(0);
+        int rssi = parser.nextInt();
 
-        position.setSpeed(UnitsConverter.knotsFromKph(parser.nextDouble(0)));
-        position.setCourse(parser.nextDouble(0));
+        position.setSpeed(UnitsConverter.knotsFromKph(parser.nextDouble()));
+        position.setCourse(parser.nextDouble());
 
         position.set(Position.KEY_HDOP, parser.nextDouble());
 
-        position.setAltitude(parser.nextDouble(0));
+        position.setAltitude(parser.nextDouble());
 
-        position.set(Position.KEY_ODOMETER, parser.nextInt(0));
+        position.set(Position.KEY_ODOMETER, parser.nextInt());
         position.set("runtime", parser.next());
 
         position.setNetwork(new Network(CellTower.from(
-                parser.nextInt(0), parser.nextInt(0), parser.nextHexInt(0), parser.nextHexInt(0), rssi)));
+                parser.nextInt(), parser.nextInt(), parser.nextHexInt(), parser.nextHexInt(), rssi)));
 
-        position.set(Position.KEY_STATUS, parser.next());
+        position.set(Position.KEY_OUTPUT, parser.nextHexInt());
+        position.set(Position.KEY_INPUT, parser.nextHexInt());
 
         for (int i = 1; i <= 3; i++) {
-            if (parser.hasNext()) {
-                position.set(Position.PREFIX_ADC + i, parser.nextHexInt(0));
-            }
+            position.set(Position.PREFIX_ADC + i, parser.nextHexInt());
         }
 
         String deviceModel = Context.getIdentityManager().getById(deviceSession.getDeviceId()).getModel();
diff --git a/src/main/java/org/traccar/protocol/Minifinder2ProtocolDecoder.java b/src/main/java/org/traccar/protocol/Minifinder2ProtocolDecoder.java
index b6f257d2c..b8ab134c5 100644
--- a/src/main/java/org/traccar/protocol/Minifinder2ProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/Minifinder2ProtocolDecoder.java
@@ -154,6 +154,15 @@ public class Minifinder2ProtocolDecoder extends BaseProtocolDecoder {
                                     mac.substring(0, mac.length() - 1), rssi));
                         }
                         break;
+                    case 0x23:
+                        if (endIndex > buf.readerIndex()) {
+                            buf.skipBytes(6); // mac
+                        }
+                        if (endIndex > buf.readerIndex()) {
+                            position.setLatitude(buf.readIntLE() * 0.0000001);
+                            position.setLongitude(buf.readIntLE() * 0.0000001);
+                        }
+                        break;
                     case 0x24:
                         position.setTime(new Date(buf.readUnsignedIntLE() * 1000));
                         long status = buf.readUnsignedIntLE();
diff --git a/src/main/java/org/traccar/protocol/OkoProtocolDecoder.java b/src/main/java/org/traccar/protocol/OkoProtocolDecoder.java
index 5adf61494..4d9c9afc4 100644
--- a/src/main/java/org/traccar/protocol/OkoProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/OkoProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 - 2018 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -36,7 +36,7 @@ public class OkoProtocolDecoder extends BaseProtocolDecoder {
     private static final Pattern PATTERN = new PatternBuilder()
             .text("{")
             .number("(d{15}),").optional()       // imei
-            .number("(dd)(dd)(dd).d+,")          // time
+            .number("(dd)(dd)(dd)(?:.d+)?,")     // time
             .expression("([AV]),")               // validity
             .number("(dd)(dd.d+),")              // latitude
             .expression("([NS]),")
@@ -46,14 +46,23 @@ public class OkoProtocolDecoder extends BaseProtocolDecoder {
             .number("(d+.?d*)?,")                // course
             .number("(dd)(dd)(dd),")             // date (ddmmyy)
             .number("(d+),")                     // satellites
-            .number("(d+.d+),")                  // adc
+            .number("(d+.d+|xx),")               // adc
             .number("(xx),")                     // event
-            .number("(d+.d+),")                  // power
+            .number("(d+.d+|xx),")               // power
             .number("d,")                        // memory status
-            .number("(xx)")                      // io
+            .number("(xx)?")                     // io
             .any()
             .compile();
 
+    private double decodeVoltage(Parser parser) {
+        String value = parser.next();
+        if (value.contains(".")) {
+            return Double.parseDouble(value);
+        } else {
+            return Integer.parseInt(value, 16) * 0.1;
+        }
+    }
+
     @Override
     protected Object decode(
             Channel channel, SocketAddress remoteAddress, Object msg) throws Exception {
@@ -89,9 +98,9 @@ public class OkoProtocolDecoder extends BaseProtocolDecoder {
         position.setTime(dateBuilder.getDate());
 
         position.set(Position.KEY_SATELLITES, parser.nextInt());
-        position.set(Position.PREFIX_ADC + 1, parser.nextDouble());
+        position.set(Position.PREFIX_ADC + 1, decodeVoltage(parser));
         position.set(Position.KEY_EVENT, parser.next());
-        position.set(Position.KEY_POWER, parser.nextDouble());
+        position.set(Position.KEY_POWER, decodeVoltage(parser));
         position.set(Position.KEY_INPUT, parser.nextHexInt());
 
         return position;
diff --git a/src/main/java/org/traccar/protocol/OmnicommFrameDecoder.java b/src/main/java/org/traccar/protocol/OmnicommFrameDecoder.java
index 1caf6ceb9..314f19757 100644
--- a/src/main/java/org/traccar/protocol/OmnicommFrameDecoder.java
+++ b/src/main/java/org/traccar/protocol/OmnicommFrameDecoder.java
@@ -27,11 +27,11 @@ public class OmnicommFrameDecoder extends BaseFrameDecoder {
     protected Object decode(
             ChannelHandlerContext ctx, Channel channel, ByteBuf buf) throws Exception {
 
-        if (buf.readableBytes() < 10) {
+        if (buf.readableBytes() < 6) {
             return null;
         }
 
-        int endIndex = buf.getUnsignedShortLE(2) + buf.readerIndex() + 6;
+        int endIndex = buf.getUnsignedShortLE(buf.readerIndex() + 2) + buf.readerIndex() + 6;
         if (buf.writerIndex() < endIndex) {
             return null;
         }
diff --git a/src/main/java/org/traccar/protocol/OmnicommProtocolDecoder.java b/src/main/java/org/traccar/protocol/OmnicommProtocolDecoder.java
index cd8b74c9a..6e9cf52a5 100644
--- a/src/main/java/org/traccar/protocol/OmnicommProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/OmnicommProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2019 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -111,16 +111,29 @@ public class OmnicommProtocolDecoder extends BaseProtocolDecoder {
                 Position position = new Position(getProtocolName());
                 position.setDeviceId(deviceSession.getDeviceId());
 
+                if (message.hasGeneral()) {
+                    OmnicommMessageOuterClass.OmnicommMessage.General data = message.getGeneral();
+                    position.set(Position.KEY_POWER, data.getUboard() * 0.1);
+                    position.set(Position.KEY_BATTERY_LEVEL, data.getBatLife());
+                }
+
                 if (message.hasNAV()) {
-                    OmnicommMessageOuterClass.OmnicommMessage.NAV nav = message.getNAV();
+                    OmnicommMessageOuterClass.OmnicommMessage.NAV data = message.getNAV();
                     position.setValid(true);
-                    position.setTime(new Date((nav.getGPSTime() + 1230768000) * 1000L)); // from 2009-01-01 12:00
-                    position.setLatitude(nav.getLAT() * 0.0000001);
-                    position.setLongitude(nav.getLON() * 0.0000001);
-                    position.setSpeed(UnitsConverter.knotsFromKph(nav.getGPSVel() * 0.1));
-                    position.setCourse(nav.getGPSDir());
-                    position.setAltitude(nav.getGPSAlt() * 0.1);
-                    position.set(Position.KEY_SATELLITES, nav.getGPSNSat());
+                    position.setTime(new Date((data.getGPSTime() + 1230768000) * 1000L)); // from 2009-01-01 12:00
+                    position.setLatitude(data.getLAT() * 0.0000001);
+                    position.setLongitude(data.getLON() * 0.0000001);
+                    position.setSpeed(UnitsConverter.knotsFromKph(data.getGPSVel() * 0.1));
+                    position.setCourse(data.getGPSDir());
+                    position.setAltitude(data.getGPSAlt() * 0.1);
+                    position.set(Position.KEY_SATELLITES, data.getGPSNSat());
+                }
+
+                if (message.hasLLSDt()) {
+                    OmnicommMessageOuterClass.OmnicommMessage.LLSDt data = message.getLLSDt();
+                    position.set("fuel1Temp", data.getTLLS1());
+                    position.set("fuel1", data.getCLLS1());
+                    position.set("fuel1State", data.getFLLS1());
                 }
 
                 if (position.getFixTime() != null) {
diff --git a/src/main/java/org/traccar/protocol/OsmAndProtocolDecoder.java b/src/main/java/org/traccar/protocol/OsmAndProtocolDecoder.java
index 3bc71de81..ec9bbc240 100644
--- a/src/main/java/org/traccar/protocol/OsmAndProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/OsmAndProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013 - 2018 Anton Tananaev (anton@traccar.org)
+ * Copyright 2013 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,15 +15,19 @@
  */
 package org.traccar.protocol;
 
+import io.netty.buffer.Unpooled;
 import io.netty.channel.Channel;
 import io.netty.handler.codec.http.FullHttpRequest;
 import io.netty.handler.codec.http.HttpResponseStatus;
 import io.netty.handler.codec.http.QueryStringDecoder;
 import org.traccar.BaseHttpProtocolDecoder;
+import org.traccar.Context;
 import org.traccar.DeviceSession;
 import org.traccar.Protocol;
+import org.traccar.database.CommandsManager;
 import org.traccar.helper.DateUtil;
 import org.traccar.model.CellTower;
+import org.traccar.model.Command;
 import org.traccar.model.Network;
 import org.traccar.model.Position;
 import org.traccar.model.WifiAccessPoint;
@@ -173,7 +177,18 @@ public class OsmAndProtocolDecoder extends BaseHttpProtocolDecoder {
         }
 
         if (position.getDeviceId() != 0) {
-            sendResponse(channel, HttpResponseStatus.OK);
+            String response = null;
+            CommandsManager commandsManager = Context.getCommandsManager();
+            if (commandsManager != null) {
+                for (Command command : commandsManager.readQueuedCommands(position.getDeviceId(), 1)) {
+                    response = command.getString(Command.KEY_DATA);
+                }
+            }
+            if (response != null) {
+                sendResponse(channel, HttpResponseStatus.OK, Unpooled.copiedBuffer(response, StandardCharsets.UTF_8));
+            } else {
+                sendResponse(channel, HttpResponseStatus.OK);
+            }
             return position;
         } else {
             sendResponse(channel, HttpResponseStatus.BAD_REQUEST);
@@ -181,4 +196,8 @@ public class OsmAndProtocolDecoder extends BaseHttpProtocolDecoder {
         }
     }
 
+    @Override
+    protected void sendQueuedCommands(Channel channel, SocketAddress remoteAddress, long deviceId) {
+    }
+
 }
diff --git a/src/main/java/org/traccar/protocol/PacificTrackProtocolDecoder.java b/src/main/java/org/traccar/protocol/PacificTrackProtocolDecoder.java
index 15e08d7b1..d49a73a86 100644
--- a/src/main/java/org/traccar/protocol/PacificTrackProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/PacificTrackProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2019 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -63,7 +63,7 @@ public class PacificTrackProtocolDecoder extends BaseProtocolDecoder {
         while (buf.isReadable()) {
 
             int segmentId = readBitExt(buf);
-            int segmentLength = readBitExt(buf);
+            int segmentEnd = readBitExt(buf) + buf.readerIndex();
 
             switch (segmentId) {
                 case 0x01:
@@ -83,12 +83,60 @@ public class PacificTrackProtocolDecoder extends BaseProtocolDecoder {
                     position.setSpeed(UnitsConverter.knotsFromKph(BitUtil.to(speedAndCourse, 12) * 0.1));
                     position.set(Position.KEY_INDEX, buf.readUnsignedShort());
                     break;
+                case 0x92:
+                    while (buf.readerIndex() < segmentEnd) {
+                        int field = buf.readUnsignedByte();
+                        int fieldPrefix = BitUtil.from(field, 5);
+                        if (fieldPrefix < 0b100) {
+                            switch (BitUtil.between(field, 2, 5)) {
+                                case 0b000:
+                                    position.set("bus", BitUtil.to(field, 2));
+                                case 0b001:
+                                    position.set("currentGear", BitUtil.to(field, 2));
+                                    break;
+                                default:
+                                    break;
+                            }
+                        } else if (fieldPrefix < 0b101) {
+                            switch (BitUtil.to(field, 5)) {
+                                case 0b00000:
+                                    position.set(Position.KEY_OBD_SPEED, buf.readUnsignedByte());
+                                    break;
+                                case 0b00001:
+                                    position.set(Position.KEY_RPM, buf.readUnsignedByte() * 32);
+                                    break;
+                                default:
+                                    buf.readUnsignedByte();
+                                    break;
+                            }
+                        } else if (fieldPrefix < 0b110) {
+                            buf.readUnsignedShort();
+                        }  else if (fieldPrefix < 0b111) {
+                            switch (BitUtil.to(field, 5)) {
+                                case 0b00000:
+                                    position.set(Position.KEY_ODOMETER, buf.readUnsignedInt() * 100);
+                                    break;
+                                case 0b00001:
+                                    position.set(Position.KEY_HOURS, buf.readUnsignedInt() * 180);
+                                    break;
+                                case 0b00010:
+                                    position.set("idleHours", buf.readUnsignedInt() * 180);
+                                    break;
+                                default:
+                                    buf.readUnsignedInt();
+                                    break;
+                            }
+                        } else {
+                            buf.skipBytes(buf.readUnsignedByte());
+                        }
+                    }
+                    break;
                 case 0x100:
                     String imei = ByteBufUtil.hexDump(buf.readSlice(8)).substring(0, 15);
                     deviceSession = getDeviceSession(channel, remoteAddress, imei);
                     break;
                 default:
-                    buf.skipBytes(segmentLength);
+                    buf.readerIndex(segmentEnd);
                     break;
             }
         }
diff --git a/src/main/java/org/traccar/protocol/PiligrimProtocolDecoder.java b/src/main/java/org/traccar/protocol/PiligrimProtocolDecoder.java
index 47aa86da7..26ce2fe53 100644
--- a/src/main/java/org/traccar/protocol/PiligrimProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/PiligrimProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2014 - 2018 Anton Tananaev (anton@traccar.org)
+ * Copyright 2014 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -18,15 +18,11 @@ package org.traccar.protocol;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.Unpooled;
 import io.netty.channel.Channel;
-import io.netty.handler.codec.http.DefaultFullHttpResponse;
 import io.netty.handler.codec.http.FullHttpRequest;
-import io.netty.handler.codec.http.FullHttpResponse;
 import io.netty.handler.codec.http.HttpResponseStatus;
-import io.netty.handler.codec.http.HttpVersion;
 import io.netty.handler.codec.http.QueryStringDecoder;
-import org.traccar.BaseProtocolDecoder;
+import org.traccar.BaseHttpProtocolDecoder;
 import org.traccar.DeviceSession;
-import org.traccar.NetworkMessage;
 import org.traccar.Protocol;
 import org.traccar.helper.BitUtil;
 import org.traccar.helper.DateBuilder;
@@ -37,19 +33,14 @@ import java.nio.charset.StandardCharsets;
 import java.util.LinkedList;
 import java.util.List;
 
-public class PiligrimProtocolDecoder extends BaseProtocolDecoder {
+public class PiligrimProtocolDecoder extends BaseHttpProtocolDecoder {
 
     public PiligrimProtocolDecoder(Protocol protocol) {
         super(protocol);
     }
 
     private void sendResponse(Channel channel, String message) {
-        if (channel != null) {
-            FullHttpResponse response = new DefaultFullHttpResponse(
-                    HttpVersion.HTTP_1_1, HttpResponseStatus.OK,
-                    Unpooled.copiedBuffer(message, StandardCharsets.US_ASCII));
-            channel.writeAndFlush(new NetworkMessage(response, channel.remoteAddress()));
-        }
+        sendResponse(channel, HttpResponseStatus.OK, Unpooled.copiedBuffer(message, StandardCharsets.US_ASCII));
     }
 
     public static final int MSG_GPS = 0xF1;
diff --git a/src/main/java/org/traccar/protocol/RstProtocolDecoder.java b/src/main/java/org/traccar/protocol/RstProtocolDecoder.java
index 8981c117b..05601ed51 100644
--- a/src/main/java/org/traccar/protocol/RstProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/RstProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2019 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/src/main/java/org/traccar/protocol/SigfoxProtocolDecoder.java b/src/main/java/org/traccar/protocol/SigfoxProtocolDecoder.java
index 304f61836..5fc81085b 100644
--- a/src/main/java/org/traccar/protocol/SigfoxProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/SigfoxProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 - 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -48,6 +48,31 @@ public class SigfoxProtocolDecoder extends BaseHttpProtocolDecoder {
         super(protocol);
     }
 
+    private boolean jsonContains(JsonObject json, String key) {
+        if (json.containsKey(key)) {
+            JsonValue value = json.get(key);
+            if (value.getValueType() == JsonValue.ValueType.STRING) {
+                return !((JsonString) value).getString().equals("null");
+
+            } else {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    private boolean getJsonBoolean(JsonObject json, String key) {
+        JsonValue value = json.get(key);
+        if (value != null) {
+            if (value.getValueType() == JsonValue.ValueType.STRING) {
+                return Boolean.parseBoolean(((JsonString) value).getString());
+            } else {
+                return value.getValueType() == JsonValue.ValueType.TRUE;
+            }
+        }
+        return false;
+    }
+
     private int getJsonInt(JsonObject json, String key) {
         JsonValue value = json.get(key);
         if (value != null) {
@@ -83,7 +108,14 @@ public class SigfoxProtocolDecoder extends BaseHttpProtocolDecoder {
         }
         JsonObject json = Json.createReader(new StringReader(content)).readObject();
 
-        DeviceSession deviceSession = getDeviceSession(channel, remoteAddress, json.getString("device"));
+        String deviceId;
+        if (json.containsKey("device")) {
+            deviceId = json.getString("device");
+        } else {
+            deviceId = json.getString("deviceId");
+        }
+
+        DeviceSession deviceSession = getDeviceSession(channel, remoteAddress, deviceId);
         if (deviceSession == null) {
             sendResponse(channel, HttpResponseStatus.BAD_REQUEST);
             return null;
@@ -92,29 +124,36 @@ public class SigfoxProtocolDecoder extends BaseHttpProtocolDecoder {
         Position position = new Position(getProtocolName());
         position.setDeviceId(deviceSession.getDeviceId());
 
-        if (json.containsKey("time")) {
+        if (jsonContains(json, "time")) {
             position.setTime(new Date(getJsonInt(json, "time") * 1000L));
+        } else if (jsonContains(json, "positionTime")) {
+            position.setTime(new Date(getJsonInt(json, "positionTime") * 1000L));
         } else {
             position.setTime(new Date());
         }
 
-        if (json.containsKey("location")
-                || json.containsKey("lat") && json.containsKey("lng") && !json.containsKey("data")) {
+        if (jsonContains(json, "lastSeen")) {
+            position.setDeviceTime(new Date(getJsonInt(json, "lastSeen") * 1000L));
+        }
+
+        if (jsonContains(json, "location")
+                || jsonContains(json, "lat") && jsonContains(json, "lng") && !jsonContains(json, "data")
+                || jsonContains(json, "latitude") && jsonContains(json, "longitude") && !jsonContains(json, "data")) {
 
             JsonObject location;
-            if (json.containsKey("location")) {
+            if (jsonContains(json, "location")) {
                 location = json.getJsonObject("location");
             } else {
                 location = json;
             }
 
             position.setValid(true);
-            position.setLatitude(getJsonDouble(location, "lat"));
-            position.setLongitude(getJsonDouble(location, "lng"));
+            position.setLatitude(getJsonDouble(location, jsonContains(location, "lat") ? "lat" : "latitude"));
+            position.setLongitude(getJsonDouble(location, jsonContains(location, "lng") ? "lng" : "longitude"));
 
-        } else {
+        } else if (jsonContains(json, "data") || jsonContains(json, "payload")) {
 
-            String data = json.getString(json.containsKey("data") ? "data" : "payload");
+            String data = json.getString(jsonContains(json, "data") ? "data" : "payload");
             ByteBuf buf = Unpooled.wrappedBuffer(DataConverter.parseHex(data));
             try {
                 int event = buf.readUnsignedByte();
@@ -205,10 +244,19 @@ public class SigfoxProtocolDecoder extends BaseHttpProtocolDecoder {
             getLastLocation(position, position.getDeviceTime());
         }
 
-        if (json.containsKey("rssi")) {
+        if (jsonContains(json, "moving")) {
+            position.set(Position.KEY_MOTION, getJsonBoolean(json, "moving"));
+        }
+        if (jsonContains(json, "magStatus")) {
+            position.set(Position.KEY_BLOCKED, getJsonBoolean(json, "magStatus"));
+        }
+        if (jsonContains(json, "temperature")) {
+            position.set(Position.KEY_DEVICE_TEMP, getJsonDouble(json, "temperature"));
+        }
+        if (jsonContains(json, "rssi")) {
             position.set(Position.KEY_RSSI, getJsonDouble(json, "rssi"));
         }
-        if (json.containsKey("seqNumber")) {
+        if (jsonContains(json, "seqNumber")) {
             position.set(Position.KEY_INDEX, getJsonInt(json, "seqNumber"));
         }
 
diff --git a/src/main/java/org/traccar/protocol/SolarPoweredProtocolDecoder.java b/src/main/java/org/traccar/protocol/SolarPoweredProtocolDecoder.java
index eae37386a..6fe54b0b0 100644
--- a/src/main/java/org/traccar/protocol/SolarPoweredProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/SolarPoweredProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2019 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -77,10 +77,24 @@ public class SolarPoweredProtocolDecoder extends BaseProtocolDecoder {
                             position.setLongitude(-position.getLongitude());
                         }
                         position.setSpeed(UnitsConverter.knotsFromKph(buf.readUnsignedByte()));
-                        position.set(Position.KEY_DEVICE_TEMP, (int) buf.readByte());
+                        int temperature = buf.readUnsignedByte();
+                        if (BitUtil.check(temperature, 7)) {
+                            position.set(Position.KEY_DEVICE_TEMP, -BitUtil.to(temperature, 7));
+                        } else {
+                            position.set(Position.KEY_DEVICE_TEMP, BitUtil.to(temperature, 7));
+                        }
                         position.set(Position.KEY_BATTERY, buf.readUnsignedByte() * 0.02);
                         position.setCourse(buf.readUnsignedByte());
                         break;
+                    case 0x83:
+                        buf.readUnsignedInt(); // uptime
+                        buf.readUnsignedInt(); // gps count
+                        buf.readUnsignedInt(); // gsm count
+                        buf.readUnsignedByte(); // positioning time
+                        buf.readUnsignedByte(); // registration time
+                        buf.readUnsignedByte(); // connection time
+                        position.set(Position.KEY_RSSI, buf.readUnsignedByte());
+                        break;
                     default:
                         buf.skipBytes(length);
                         break;
diff --git a/src/main/java/org/traccar/protocol/StarLinkProtocolDecoder.java b/src/main/java/org/traccar/protocol/StarLinkProtocolDecoder.java
index bad6f03a9..2d1613e03 100644
--- a/src/main/java/org/traccar/protocol/StarLinkProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/StarLinkProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 - 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -140,6 +140,11 @@ public class StarLinkProtocolDecoder extends BaseProtocolDecoder {
                     event = Integer.parseInt(data[i]);
                     position.set(Position.KEY_ALARM, decodeAlarm(event));
                     position.set(Position.KEY_EVENT, event);
+                    if (event == 24) {
+                        position.set(Position.KEY_IGNITION, true);
+                    } else if (event == 25) {
+                        position.set(Position.KEY_IGNITION, false);
+                    }
                     break;
                 case "#PDT#":
                     position.setFixTime(dateFormat.parse(data[i]));
diff --git a/src/main/java/org/traccar/protocol/SuntechProtocolDecoder.java b/src/main/java/org/traccar/protocol/SuntechProtocolDecoder.java
index 915f764e1..978d768be 100644
--- a/src/main/java/org/traccar/protocol/SuntechProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/SuntechProtocolDecoder.java
@@ -397,7 +397,7 @@ public class SuntechProtocolDecoder extends BaseProtocolDecoder {
 
             if (isIncludeAdc(deviceSession.getDeviceId())) {
                 for (int i = 1; i <= 3; i++) {
-                    if (!values[index++].isEmpty()) {
+                    if (index < values.length && !values[index++].isEmpty()) {
                         position.set(Position.PREFIX_ADC + i, Double.parseDouble(values[index - 1]));
                     }
                 }
@@ -614,10 +614,21 @@ public class SuntechProtocolDecoder extends BaseProtocolDecoder {
             position.set(Position.KEY_OUTPUT, buf.readUnsignedByte());
         }
 
+        int alertId = 0;
         if (BitUtil.check(mask, 19)) {
-            int value = buf.readUnsignedByte();
+            alertId = buf.readUnsignedByte();
             if (type == 0x82) {
-                position.set(Position.KEY_ALARM, decodeAlert(value));
+                position.set(Position.KEY_ALARM, decodeAlert(alertId));
+            }
+        }
+
+        if (BitUtil.check(mask, 20)) {
+            buf.readUnsignedShort(); // alert mod
+        }
+
+        if (BitUtil.check(mask, 21)) {
+            if (alertId == 59) {
+                position.set(Position.KEY_DRIVER_UNIQUE_ID, ByteBufUtil.hexDump(buf.readSlice(8)));
             }
         }
 
diff --git a/src/main/java/org/traccar/protocol/T800xProtocolDecoder.java b/src/main/java/org/traccar/protocol/T800xProtocolDecoder.java
index 9b146ec90..3331ebb71 100644
--- a/src/main/java/org/traccar/protocol/T800xProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/T800xProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 - 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2015 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -177,8 +177,7 @@ public class T800xProtocolDecoder extends BaseProtocolDecoder {
     }
 
     private Position decodePosition(
-            Channel channel, DeviceSession deviceSession,
-            ByteBuf buf, int type, int index, ByteBuf imei) {
+            Channel channel, DeviceSession deviceSession, ByteBuf buf, int type, int index, ByteBuf imei) {
 
         Position position = new Position(getProtocolName());
         position.setDeviceId(deviceSession.getDeviceId());
@@ -214,8 +213,10 @@ public class T800xProtocolDecoder extends BaseProtocolDecoder {
                 position.set(Position.PREFIX_OUT + (i + 1), BitUtil.check(io, 7 + i));
             }
 
-            position.set(Position.PREFIX_ADC + 1, buf.readUnsignedShort());
-            position.set(Position.PREFIX_ADC + 2, buf.readUnsignedShort());
+            if (header != 0x2626) {
+                position.set(Position.PREFIX_ADC + 1, buf.readUnsignedShort());
+                position.set(Position.PREFIX_ADC + 2, buf.readUnsignedShort());
+            }
 
         }
 
diff --git a/src/main/java/org/traccar/protocol/TelicProtocolDecoder.java b/src/main/java/org/traccar/protocol/TelicProtocolDecoder.java
index 457687b2e..a4f9e2989 100644
--- a/src/main/java/org/traccar/protocol/TelicProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/TelicProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2014 - 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2014 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -42,8 +42,8 @@ public class TelicProtocolDecoder extends BaseProtocolDecoder {
             .number("(dd)(dd)(dd)")              // date (ddmmyy)
             .number("(dd)(dd)(dd),")             // time (hhmmss)
             .groupBegin()
-            .number("(-?d{9}),")                 // longitude
-            .number("(-?d{8}),")                 // latitude
+            .number("(-?d{8,}),")                // longitude
+            .number("(-?d{7,}),")                // latitude
             .or()
             .number("(-?d+),")                   // longitude
             .number("(-?d+),")                   // latitude
diff --git a/src/main/java/org/traccar/protocol/Tlt2hProtocolDecoder.java b/src/main/java/org/traccar/protocol/Tlt2hProtocolDecoder.java
index 7ad99b37e..3ce6438f8 100644
--- a/src/main/java/org/traccar/protocol/Tlt2hProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/Tlt2hProtocolDecoder.java
@@ -38,7 +38,7 @@ public class Tlt2hProtocolDecoder extends BaseProtocolDecoder {
     private static final Pattern PATTERN_HEADER = new PatternBuilder()
             .number("#(d+)")                     // imei
             .expression("#[^#]*")                // user
-            .number("#d+")                       // password
+            .number("#d*")                       // password
             .groupBegin()
             .number("#([01])")                   // door
             .number("#(d+)")                     // fuel voltage
diff --git a/src/main/java/org/traccar/protocol/TopinProtocolDecoder.java b/src/main/java/org/traccar/protocol/TopinProtocolDecoder.java
index ea72b7cb8..eee0e9ae8 100644
--- a/src/main/java/org/traccar/protocol/TopinProtocolDecoder.java
+++ b/src/main/java/org/traccar/protocol/TopinProtocolDecoder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2019 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,6 +23,8 @@ import org.traccar.BaseProtocolDecoder;
 import org.traccar.DeviceSession;
 import org.traccar.NetworkMessage;
 import org.traccar.Protocol;
+import org.traccar.helper.BcdUtil;
+import org.traccar.helper.DateBuilder;
 import org.traccar.model.CellTower;
 import org.traccar.model.Network;
 import org.traccar.model.Position;
@@ -44,11 +46,11 @@ public class TopinProtocolDecoder extends BaseProtocolDecoder {
     public static final int MSG_WIFI_OFFLINE = 0x17;
     public static final int MSG_WIFI = 0x69;
 
-    private void sendResponse(Channel channel, int type, ByteBuf content) {
+    private void sendResponse(Channel channel, int length, int type, ByteBuf content) {
         if (channel != null) {
             ByteBuf response = Unpooled.buffer();
             response.writeShort(0x7878);
-            response.writeByte(1 + content.readableBytes());
+            response.writeByte(length);
             response.writeByte(type);
             response.writeBytes(content);
             response.writeByte('\r');
@@ -75,7 +77,7 @@ public class TopinProtocolDecoder extends BaseProtocolDecoder {
             deviceSession = getDeviceSession(channel, remoteAddress, imei);
             ByteBuf content = Unpooled.buffer();
             content.writeByte(deviceSession != null ? 0x01 : 0x44);
-            sendResponse(channel, type, content);
+            sendResponse(channel, length, type, content);
             return null;
         } else {
             deviceSession = getDeviceSession(channel, remoteAddress);
@@ -95,7 +97,7 @@ public class TopinProtocolDecoder extends BaseProtocolDecoder {
 
             ByteBuf content = Unpooled.buffer();
             content.writeBytes(time);
-            sendResponse(channel, type, content);
+            sendResponse(channel, length, type, content);
 
             return position;
 
@@ -127,7 +129,7 @@ public class TopinProtocolDecoder extends BaseProtocolDecoder {
             if (length >= 7) {
                 content.writeByte(signal);
             }
-            sendResponse(channel, type, content);
+            sendResponse(channel, length, type, content);
 
             return position;
 
@@ -136,9 +138,17 @@ public class TopinProtocolDecoder extends BaseProtocolDecoder {
             Position position = new Position(getProtocolName());
             position.setDeviceId(deviceSession.getDeviceId());
 
-            getLastLocation(position, null);
-
             ByteBuf time = buf.readSlice(6);
+            DateBuilder dateBuilder = new DateBuilder()
+                    .setYear(BcdUtil.readInteger(time, 2))
+                    .setMonth(BcdUtil.readInteger(time, 2))
+                    .setDay(BcdUtil.readInteger(time, 2))
+                    .setHour(BcdUtil.readInteger(time, 2))
+                    .setMinute(BcdUtil.readInteger(time, 2))
+                    .setSecond(BcdUtil.readInteger(time, 2));
+            time.resetReaderIndex();
+
+            getLastLocation(position, dateBuilder.getDate());
 
             Network network = new Network();
             for (int i = 0; i < length; i++) {
@@ -160,7 +170,7 @@ public class TopinProtocolDecoder extends BaseProtocolDecoder {
 
             ByteBuf content = Unpooled.buffer();
             content.writeBytes(time);
-            sendResponse(channel, type, content);
+            sendResponse(channel, length, type, content);
 
             return position;
 
diff --git a/src/main/java/org/traccar/protocol/WondexProtocol.java b/src/main/java/org/traccar/protocol/WondexProtocol.java
index 035dd9160..6401fde85 100644
--- a/src/main/java/org/traccar/protocol/WondexProtocol.java
+++ b/src/main/java/org/traccar/protocol/WondexProtocol.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 - 2019 Anton Tananaev (anton@traccar.org)
+ * Copyright 2015 - 2020 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -25,7 +25,7 @@ import io.netty.handler.codec.string.StringEncoder;
 public class WondexProtocol extends BaseProtocol {
 
     public WondexProtocol() {
-        setSupportedCommands(
+        setSupportedDataCommands(
                 Command.TYPE_GET_DEVICE_STATUS,
                 Command.TYPE_GET_MODEM_STATUS,
                 Command.TYPE_REBOOT_DEVICE,
@@ -33,6 +33,13 @@ public class WondexProtocol extends BaseProtocol {
                 Command.TYPE_GET_VERSION,
                 Command.TYPE_IDENTIFICATION);
         setTextCommandEncoder(new WondexProtocolEncoder(this));
+        setSupportedTextCommands(
+                Command.TYPE_GET_DEVICE_STATUS,
+                Command.TYPE_GET_MODEM_STATUS,
+                Command.TYPE_REBOOT_DEVICE,
+                Command.TYPE_POSITION_SINGLE,
+                Command.TYPE_GET_VERSION,
+                Command.TYPE_IDENTIFICATION);
         addServer(new TrackerServer(false, getName()) {
             @Override
             protected void addProtocolHandlers(PipelineBuilder pipeline) {