7 files changed, 316 insertions, 405 deletions
diff --git a/src/main/java/org/traccar/protocol/NDTPv6Protocol.java b/src/main/java/org/traccar/protocol/NDTPv6Protocol.java
deleted file mode 100644
index 78dc11b50..000000000
--- a/src/main/java/org/traccar/protocol/NDTPv6Protocol.java
+++ /dev/null
@@ -1,26 +0,0 @@
-/*
- * 2020 - NDTP v6 Protocol
- */
-package org.traccar.protocol;
-
-import org.traccar.BaseProtocol;
-import org.traccar.PipelineBuilder;
-import org.traccar.TrackerServer;
-import org.traccar.config.Config;
-
-import javax.inject.Inject;
-
-public class NDTPv6Protocol extends BaseProtocol {
-
-    @Inject
-    public NDTPv6Protocol(Config config) {
-        addServer(
-                new TrackerServer(config, getName(), false) {
-                    @Override
-                    protected void addProtocolHandlers(PipelineBuilder pipeline, Config config) {
-                        pipeline.addLast(new NDTPv6ProtocolDecoder(NDTPv6Protocol.this));
-                    }
-                }
-        );
-    }
-}
diff --git a/src/main/java/org/traccar/protocol/NDTPv6ProtocolDecoder.java b/src/main/java/org/traccar/protocol/NDTPv6ProtocolDecoder.java
deleted file mode 100644
index 788afd65b..000000000
--- a/src/main/java/org/traccar/protocol/NDTPv6ProtocolDecoder.java
+++ /dev/null
@@ -1,309 +0,0 @@
-/*
- * 2020 - NDTP v6 Protocol Decoder
- */
-package org.traccar.protocol;
-
-import io.netty.buffer.ByteBuf;
-import io.netty.buffer.Unpooled;
-import io.netty.channel.Channel;
-
-import java.net.SocketAddress;
-import java.nio.ByteBuffer;
-import java.nio.ByteOrder;
-import java.util.Date;
-
-import org.traccar.BaseProtocolDecoder;
-import org.traccar.NetworkMessage;
-import org.traccar.Protocol;
-import org.traccar.helper.BitUtil;
-import org.traccar.helper.Checksum;
-import org.traccar.model.Position;
-import org.traccar.session.DeviceSession;
-
-public class NDTPv6ProtocolDecoder extends BaseProtocolDecoder {
-
-    public NDTPv6ProtocolDecoder(Protocol protocol) {
-        super(protocol);
-    }
-
-    private static final byte[] SIGNATURE = {0x7E, 0x7E};
-
-    private static final int NPL_FLAG_CRC = 2;
-    private static final int NPH_RESULT_OK = 0x00000000;
-    private static final int NPL_TYPE_NPH = 2;
-    private static final int NPL_ADDRESS_SERVER = 0;
-
-    /* common packets for all services */
-    private static final int NPH_RESULT = 0;
-
-    /* NPH service types */
-    private static final int NPH_SRV_GENERIC_CONTROLS = 0;
-    private static final int NPH_SRV_NAVDATA = 1;
-
-    /* NPH_SRV_GENERIC_CONTROLS packets */
-    private static final int NPH_SGC_RESULT = NPH_RESULT;
-    private static final int NPH_SGC_CONN_REQUEST = 100;
-
-    /* NPH_SRV_NAVDATA packets */
-    private static final int NPH_SND_RESULT = NPH_RESULT;
-
-    private static void sendResultResponse(
-            Channel channel,
-            short serviceId,
-            int requestId,
-            int nphSendResult,
-            int nphResult
-    ) {
-        // Формирование пакета данных
-        byte[] serviceIdBytes = ByteBuffer
-                .allocate(2)
-                .order(ByteOrder.LITTLE_ENDIAN)
-                .putShort(serviceId)
-                .array();
-        byte[] nphSendResultBytes = ByteBuffer
-                .allocate(4)
-                .order(ByteOrder.LITTLE_ENDIAN)
-                .putInt(nphSendResult)
-                .array();
-        byte[] requestIdBytes = ByteBuffer
-                .allocate(4)
-                .order(ByteOrder.LITTLE_ENDIAN)
-                .putInt(requestId)
-                .array();
-        byte[] nphResultBytes = ByteBuffer
-                .allocate(4)
-                .order(ByteOrder.LITTLE_ENDIAN)
-                .putInt(nphResult)
-                .array();
-
-        byte[] allByteArray = new byte[serviceIdBytes.length +
-                requestIdBytes.length +
-                nphSendResultBytes.length +
-                nphResultBytes.length];
-
-        System.arraycopy(serviceIdBytes, 0, allByteArray, 0, serviceIdBytes.length);
-        System.arraycopy(
-                nphSendResultBytes,
-                0,
-                allByteArray,
-                serviceIdBytes.length,
-                nphSendResultBytes.length
-        );
-        System.arraycopy(
-                requestIdBytes,
-                0,
-                allByteArray,
-                serviceIdBytes.length + nphSendResultBytes.length,
-                requestIdBytes.length
-        );
-        System.arraycopy(
-                nphResultBytes,
-                0,
-                allByteArray,
-                serviceIdBytes.length + requestIdBytes.length + nphSendResultBytes.length,
-                nphResultBytes.length
-        );
-
-        // ПАКЕТ ОТВЕТА КЛИЕНТУ
-        ByteBuf response = Unpooled.buffer();
-        // NPL
-        response.writeBytes(SIGNATURE);
-        response.writeShortLE(allByteArray.length); // Размер данных
-        response.writeShortLE(NPL_FLAG_CRC); // Флаги
-
-        response.writeShort(
-                Checksum.crc16(Checksum.CRC16_MODBUS, ByteBuffer.wrap(allByteArray))
-        ); // CRC
-        response.writeByte(NPL_TYPE_NPH); // Тип
-        response.writeIntLE(NPL_ADDRESS_SERVER); // peer_address
-        response.writeShortLE(0); // request_id
-
-        response.writeBytes(allByteArray);
-
-        channel.writeAndFlush(
-                new NetworkMessage(response, channel.remoteAddress())
-        );
-    }
-
-    private static final short MAIN_NAV_DATA = 0;
-    private static final short ADDITIONAL_NAV_DATA = 2;
-
-    private void decodeData(ByteBuf buf, Position position, int dataType) {
-        if (dataType == NPH_SRV_NAVDATA) {
-            short cellType;
-            short cellNumber;
-
-            cellType = buf.readUnsignedByte(); // Тип ячейки
-            cellNumber = buf.readUnsignedByte(); // Номер ячейки
-            if (cellType == MAIN_NAV_DATA && (cellNumber == 0 || cellNumber == 1)) {
-                position.setTime(new Date(buf.readUnsignedIntLE() * 1000)); // Значение реального времени unix
-                position.setLongitude(buf.readIntLE() / 10000000.0); // Долгота в градусах, умноженная на 10 000 000
-                position.setLatitude(buf.readIntLE() / 10000000.0); // Широта в градусах, умноженная на 10 000 000
-
-                short flags = buf.readUnsignedByte(); // Достоверность навигационных данных:
-                // bit7 - достоверность нав. данных (1 - достоверны, 0 – нет);
-                // bit6 - полушарие долготы (1 – E, 0 – W);
-                // bit5 - полушарие широты (1 – N, 0 – S);
-                // bit4 - флаг работы от встроенного аккумулятора;
-                // bit3 – флаг первоначального включения;
-                // bit2 – состояние SOS (1 – SOS, 0 – нет SOS);
-                // bit1 – флаг тревожной информации (один из параметров
-                // находится в диапазоне тревоги)
-                position.setValid(BitUtil.check(flags, 7));
-                if (BitUtil.check(flags, 1)) {
-                    position.set(Position.KEY_ALARM, Position.ALARM_GENERAL);
-                }
-                position.set(Position.KEY_BATTERY, buf.readUnsignedByte() * 20); // Напряжение батареи, 1бит = 20мВ
-                position.set(Position.KEY_OBD_SPEED, buf.readUnsignedShortLE()); // Средняя скорость за период в км/ч
-                position.setSpeed(buf.readUnsignedShortLE() / 1.85); // Максимальная скорость за период в км/ч
-
-                int course = buf.readUnsignedShortLE(); // Направление движения
-                position.setCourse(course);
-
-                position.set(Position.KEY_DISTANCE, buf.readUnsignedShortLE()); // Пройденный путь, м
-                position.setAltitude(buf.readShortLE()); // Высота над уровнем моря в метрах (-18000 - +18000)
-                position.set(Position.KEY_SATELLITES, buf.readUnsignedByte()); // Количество видимых спутников
-                position.set(Position.KEY_PDOP, buf.readUnsignedByte()); // PDOP
-            }
-            cellType = buf.readUnsignedByte(); // Тип ячейки
-            cellNumber = buf.readUnsignedByte(); // Номер ячейки
-            if (cellType == ADDITIONAL_NAV_DATA && cellNumber == 0) {
-                int analogIn1 = buf.readUnsignedShortLE(); // Значение 0 аналогового входа в 16 битном формате
-                //(analogIn1 - отражает напряжение на батерии для радиоборта)
-                int analogIn2 = buf.readUnsignedShortLE(); // Значение 1 аналогового входа в 16 битном формате
-                int analogIn3 = buf.readUnsignedShortLE(); // Значение 2 аналогового входа в 16 битном формате
-                int analogIn4 = buf.readUnsignedShortLE(); // Значение 3 аналогового входа в 16 битном формате
-
-                buf.readUnsignedByte(); // Значение цифровых входов
-                buf.readUnsignedByte(); // Состояние дискретных выходов
-                buf.readUnsignedShortLE(); // Количество импульсов на дискретном входе 0 с предыдущей нав. отметки
-                buf.readUnsignedShortLE(); // Количество импульсов на дискретном входе 1 с предыдущей нав. отметки
-                buf.readUnsignedShortLE(); // Количество импульсов на дискретном входе 2 с предыдущей нав. отметки
-                buf.readUnsignedShortLE(); // Количество импульсов на дискретном входе 3 с предыдущей нав. отметки
-                buf.readUnsignedIntLE(); // Длина трека с момента первого включения
-
-                position.set(Position.KEY_ANTENNA, buf.readUnsignedByte()); // Сила GSM сигнала
-                position.set(Position.KEY_GPS, buf.readUnsignedByte()); // Состояние GPRS подключения
-                position.set(Position.KEY_ACCELERATION, buf.readUnsignedByte()); // Акселерометр - энергия
-                position.set(Position.KEY_POWER, buf.readUnsignedByte() * 200); // Напряжение борт. сети (1бит - 200мв)
-
-                position.set(Position.PREFIX_ADC + 1, analogIn1 * 1);
-                position.set(Position.PREFIX_ADC + 2, analogIn2 * 1);
-                position.set(Position.PREFIX_ADC + 3, analogIn3 * 1);
-                position.set(Position.PREFIX_ADC + 4, analogIn4 * 1);
-
-                // Расчет уровня батареи
-                // float Voltage = 5 / 4096 * analogIn1; // Вольтаж
-
-                float batteryLevel = (analogIn1 - 3600) / 6;
-
-                if (batteryLevel > 100) {
-                    batteryLevel = 100;
-                }
-                if (batteryLevel < 0) {
-                    batteryLevel = 0;
-                }
-
-                position.set(Position.KEY_BATTERY_LEVEL, batteryLevel);
-            }
-        }
-    }
-
-    @Override
-    protected Object decode(
-            Channel channel,
-            SocketAddress remoteAddress,
-            Object msg
-    )
-            throws Exception {
-        ByteBuf buf = (ByteBuf) msg;
-
-        DeviceSession deviceSession = getDeviceSession(channel, remoteAddress);
-
-        // Заголовок NPL
-        buf.skipBytes(2); // Сигнатура (7e 7e)
-        buf.readUnsignedShortLE(); // Размер данных (nph + размер массива данных)
-        buf.readUnsignedShortLE(); // Флаги соединения (2 - проверять crc)
-        buf.readUnsignedShortLE(); // CRC (Modbus)
-        buf.readUnsignedByte(); // Тип пакета (nph)
-        buf.readUnsignedIntLE(); // Адрес участника соединения
-        buf.readUnsignedShortLE(); // Идентификатор NPL
-
-        // Заголовок NPH
-        int serviceId = buf.readUnsignedShortLE(); // Идентификатор услуги (NPH_SRV_NAVDATA) service_id
-        int serviceType = buf.readUnsignedShortLE(); // Тип пакета
-        buf.readUnsignedShortLE(); // Флаг (1 - требуется подтверждение) NPH_FLAG_REQUEST
-        long requestId = buf.readUnsignedIntLE(); // Идентификатор nph
-
-        if (
-                deviceSession == null &&
-                        serviceId == NPH_SRV_GENERIC_CONTROLS &&
-                        serviceType == NPH_SGC_CONN_REQUEST
-        ) { // Регистрация устройства
-            buf.readUnsignedShortLE(); // Версия протокола NDTP (старший номер)
-            buf.readUnsignedShortLE(); // Версия протокола NDTP (младший номер)
-            buf.readUnsignedShortLE(); // Опции соединения (connection_flags)
-            // Определяет настройки соединения,
-            // которые будут использоваться после установки соединения.
-            // На данный момент их две:
-            //  - бит0: шифровать пакеты (0 - нет, 1 — да)
-            //  - бит1: рассчитывать CRC пакетов (0 - нет, 1 — да)
-            //  - бит2: подключение симулятора (0 — подключается обычный клиент,
-            //                                  1 подключается симулятор)
-            //  - бит3:  тип алгоритма шифрования.
-            //  -            0 - blowfish
-            //  -            1 – ГОСТ
-            //  - бит8: наличие поля IMEI (0 - нет, 1 — да)
-            //  - бит9: наличие поля IMSI (0 - нет, 1 — да)
-            //  - остальные биты не используются.
-            int deviceId = buf.readUnsignedShortLE();
-            Position position = new Position(getProtocolName());
-            deviceSession =
-                    getDeviceSession(channel, remoteAddress, String.valueOf(deviceId));
-            position.setDeviceId(deviceSession.getDeviceId());
-
-            if (channel != null) {
-                sendResultResponse(
-                        channel,
-                        (short) serviceId,
-                        (int) requestId,
-                        NPH_SND_RESULT,
-                        NPH_RESULT_OK
-                );
-            }
-
-            position.set(Position.KEY_RESULT, String.valueOf(NPH_SGC_RESULT));
-            position.setTime(new Date());
-            getLastLocation(position, new Date());
-            position.setValid(false);
-
-            return position;
-        }
-
-        if (serviceId == NPH_SRV_NAVDATA) {
-            deviceSession = getDeviceSession(channel, remoteAddress);
-            if (deviceSession == null) {
-                return null;
-            }
-
-            Position position = new Position(getProtocolName());
-            position.setDeviceId(deviceSession.getDeviceId());
-
-            if (channel != null) {
-                sendResultResponse(
-                        channel,
-                        (short) serviceId,
-                        (int) requestId,
-                        NPH_SND_RESULT,
-                        NPH_RESULT_OK
-                );
-            }
-
-            decodeData(buf, position, NPH_SRV_NAVDATA);
-
-            return position;
-        }
-
-        return null;
-    }
-}
diff --git a/src/main/java/org/traccar/protocol/NDTPv6ProtocolEncoder.java b/src/main/java/org/traccar/protocol/NDTPv6ProtocolEncoder.java
deleted file mode 100644
index af0dd58f9..000000000
--- a/src/main/java/org/traccar/protocol/NDTPv6ProtocolEncoder.java
+++ /dev/null
@@ -1,38 +0,0 @@
-/*
- * 2020 - NDTP v6 Protocol Encoder
- */
-package org.traccar.protocol;
-
-import io.netty.buffer.ByteBuf;
-import io.netty.buffer.Unpooled;
-import java.nio.charset.StandardCharsets;
-import org.traccar.BaseProtocolEncoder;
-import org.traccar.Protocol;
-import org.traccar.model.Command;
-
-public class NDTPv6ProtocolEncoder extends BaseProtocolEncoder {
-
-  public NDTPv6ProtocolEncoder(Protocol protocol) {
-    super(protocol);
-  }
-
-  private ByteBuf encodeCommand(String commandString) {
-    ByteBuf buffer = Unpooled.buffer();
-    buffer.writeBytes(commandString.getBytes(StandardCharsets.US_ASCII));
-    return buffer;
-  }
-
-  @Override
-  protected Object encodeCommand(Command command) {
-    switch (command.getType()) {
-      case Command.TYPE_IDENTIFICATION:
-        return encodeCommand("BB+IDNT");
-      case Command.TYPE_REBOOT_DEVICE:
-        return encodeCommand("BB+RESET");
-      case Command.TYPE_POSITION_SINGLE:
-        return encodeCommand("BB+RRCD");
-      default:
-        return null;
-    }
-  }
-}
diff --git a/src/main/java/org/traccar/protocol/NDTPv6FrameDecoder.java b/src/main/java/org/traccar/protocol/NdtpV6FrameDecoder.java
index c869b11a4..5b610013a 100644
--- a/src/main/java/org/traccar/protocol/NDTPv6FrameDecoder.java
+++ b/src/main/java/org/traccar/protocol/NdtpV6FrameDecoder.java
@@ -1,32 +1,32 @@
-/*
- * Copyright 2016 - 2018 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 io.netty.channel.ChannelHandlerContext;
-import org.traccar.BaseFrameDecoder;
-
-public class NDTPv6FrameDecoder extends BaseFrameDecoder {
-
-    @Override
-    protected Object decode(
-            ChannelHandlerContext ctx, Channel channel, ByteBuf buf) throws Exception {
-
-        return buf;
-    }
-
-}
+/*
+ * Copyright 2022 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 io.netty.channel.ChannelHandlerContext;
+import org.traccar.BaseFrameDecoder;
+
+public class NdtpV6FrameDecoder extends BaseFrameDecoder {
+
+    @Override
+    protected Object decode(
+            ChannelHandlerContext ctx, Channel channel, ByteBuf buf) throws Exception {
+
+        return buf;
+    }
+
+}
diff --git a/src/main/java/org/traccar/protocol/NdtpV6Protocol.java b/src/main/java/org/traccar/protocol/NdtpV6Protocol.java
new file mode 100644
index 000000000..ce0dbbef2
--- /dev/null
+++ b/src/main/java/org/traccar/protocol/NdtpV6Protocol.java
@@ -0,0 +1,39 @@
+/*
+ * Copyright 2022 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.handler.codec.string.StringEncoder;
+import org.traccar.BaseProtocol;
+import org.traccar.PipelineBuilder;
+import org.traccar.TrackerServer;
+import org.traccar.config.Config;
+
+import javax.inject.Inject;
+
+public class NdtpV6Protocol extends BaseProtocol {
+
+    @Inject
+    public NdtpV6Protocol(Config config) {
+        addServer(new TrackerServer(config, getName(), false) {
+            @Override
+            protected void addProtocolHandlers(PipelineBuilder pipeline, Config config) {
+                pipeline.addLast(new StringEncoder());
+                pipeline.addLast(new NdtpV6ProtocolDecoder(NdtpV6Protocol.this));
+            }
+        });
+    }
+
+}
diff --git a/src/main/java/org/traccar/protocol/NdtpV6ProtocolDecoder.java b/src/main/java/org/traccar/protocol/NdtpV6ProtocolDecoder.java
new file mode 100644
index 000000000..35cb0bae8
--- /dev/null
+++ b/src/main/java/org/traccar/protocol/NdtpV6ProtocolDecoder.java
@@ -0,0 +1,203 @@
+/*
+ * Copyright 2022 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.buffer.Unpooled;
+import io.netty.channel.Channel;
+import org.traccar.BaseProtocolDecoder;
+import org.traccar.NetworkMessage;
+import org.traccar.Protocol;
+import org.traccar.helper.BitUtil;
+import org.traccar.helper.Checksum;
+import org.traccar.helper.UnitsConverter;
+import org.traccar.model.Position;
+import org.traccar.session.DeviceSession;
+
+import java.net.SocketAddress;
+import java.util.Date;
+
+public class NdtpV6ProtocolDecoder extends BaseProtocolDecoder {
+
+    public NdtpV6ProtocolDecoder(Protocol protocol) {
+        super(protocol);
+    }
+
+    private static final byte[] SIGNATURE = {0x7E, 0x7E};
+
+    private static final int NPL_FLAG_CRC = 2;
+    private static final int NPH_RESULT_OK = 0x00000000;
+    private static final int NPL_TYPE_NPH = 2;
+    private static final int NPL_ADDRESS_SERVER = 0;
+
+    private static final int NPH_RESULT = 0;
+
+    private static final int NPH_SRV_GENERIC_CONTROLS = 0;
+    private static final int NPH_SRV_NAVDATA = 1;
+
+    private static final int NPH_SGC_RESULT = NPH_RESULT;
+    private static final int NPH_SGC_CONN_REQUEST = 100;
+
+    private static final int NPH_SND_RESULT = NPH_RESULT;
+
+    private void sendResponse(
+            Channel channel, int serviceId, long requestId) {
+
+        ByteBuf content = Unpooled.buffer();
+        content.writeShortLE(serviceId);
+        content.writeIntLE(NPH_SND_RESULT);
+        content.writeIntLE((int) requestId);
+        content.writeIntLE(NPH_RESULT_OK);
+
+        ByteBuf response = Unpooled.buffer();
+        response.writeBytes(SIGNATURE);
+        response.writeShortLE(content.readableBytes());
+        response.writeShortLE(NPL_FLAG_CRC); // flags
+        response.writeShort(Checksum.crc16(Checksum.CRC16_MODBUS, content.nioBuffer()));
+        response.writeByte(NPL_TYPE_NPH); // type
+        response.writeIntLE(NPL_ADDRESS_SERVER); // peer address
+        response.writeShortLE(0); // request id
+        response.writeBytes(content);
+        content.release();
+
+        channel.writeAndFlush(new NetworkMessage(response, channel.remoteAddress()));
+    }
+
+    private static final short MAIN_NAV_DATA = 0;
+    private static final short ADDITIONAL_NAV_DATA = 2;
+
+    private void decodeData(ByteBuf buf, Position position) {
+
+        short itemType;
+        short itemIndex;
+
+        itemType = buf.readUnsignedByte();
+        itemIndex = buf.readUnsignedByte();
+        if (itemType == MAIN_NAV_DATA && (itemIndex == 0 || itemIndex == 1)) {
+
+            position.setTime(new Date(buf.readUnsignedIntLE() * 1000));
+            position.setLongitude(buf.readIntLE() / 10000000.0);
+            position.setLatitude(buf.readIntLE() / 10000000.0);
+
+            short flags = buf.readUnsignedByte();
+            position.setValid(BitUtil.check(flags, 7));
+            if (BitUtil.check(flags, 1)) {
+                position.set(Position.KEY_ALARM, Position.ALARM_GENERAL);
+            }
+
+            position.set(Position.KEY_BATTERY, buf.readUnsignedByte() * 20);
+            position.set(Position.KEY_OBD_SPEED, buf.readUnsignedShortLE());
+            position.setSpeed(UnitsConverter.knotsFromKph(buf.readUnsignedShortLE()));
+            position.setCourse(buf.readUnsignedShortLE());
+
+            position.set(Position.KEY_ODOMETER, buf.readUnsignedShortLE());
+            position.setAltitude(buf.readShortLE());
+            position.set(Position.KEY_SATELLITES, buf.readUnsignedByte());
+            position.set(Position.KEY_PDOP, buf.readUnsignedByte());
+        }
+
+        itemType = buf.readUnsignedByte();
+        itemIndex = buf.readUnsignedByte();
+        if (itemType == ADDITIONAL_NAV_DATA && itemIndex == 0) {
+
+            position.set(Position.KEY_BATTERY_LEVEL, Math.max((buf.readUnsignedShortLE() - 3600) / 6, 100));
+            position.set(Position.PREFIX_ADC + 2, buf.readUnsignedShortLE());
+            position.set(Position.PREFIX_ADC + 3, buf.readUnsignedShortLE());
+            position.set(Position.PREFIX_ADC + 4, buf.readUnsignedShortLE());
+
+            buf.readUnsignedByte(); // inputs
+            buf.readUnsignedByte(); // outputs
+            buf.readUnsignedShortLE(); // in1 count
+            buf.readUnsignedShortLE(); // in2 count
+            buf.readUnsignedShortLE(); // in3 count
+            buf.readUnsignedShortLE(); // in4 count
+            buf.readUnsignedIntLE(); // track length
+
+            position.set(Position.KEY_ANTENNA, buf.readUnsignedByte());
+            position.set(Position.KEY_GPS, buf.readUnsignedByte());
+            position.set(Position.KEY_ACCELERATION, buf.readUnsignedByte());
+            position.set(Position.KEY_POWER, buf.readUnsignedByte() * 200);
+        }
+    }
+
+    @Override
+    protected Object decode(
+            Channel channel, SocketAddress remoteAddress, Object msg) throws Exception {
+
+        ByteBuf buf = (ByteBuf) msg;
+
+        DeviceSession deviceSession = getDeviceSession(channel, remoteAddress);
+
+        buf.skipBytes(2); // signature
+        buf.readUnsignedShortLE(); // length
+        buf.readUnsignedShortLE(); // connection flags
+        buf.readUnsignedShortLE(); // checksum
+        buf.readUnsignedByte(); // type
+        buf.readUnsignedIntLE(); // address
+        buf.readUnsignedShortLE(); // identification
+
+        int serviceId = buf.readUnsignedShortLE();
+        int serviceType = buf.readUnsignedShortLE();
+        buf.readUnsignedShortLE(); // request flags
+        long requestId = buf.readUnsignedIntLE();
+
+        if (deviceSession == null && serviceId == NPH_SRV_GENERIC_CONTROLS && serviceType == NPH_SGC_CONN_REQUEST) {
+
+            buf.readUnsignedShortLE(); // version major
+            buf.readUnsignedShortLE(); // version minor
+            buf.readUnsignedShortLE(); // connection flags
+
+            int deviceId = buf.readUnsignedShortLE();
+            Position position = new Position(getProtocolName());
+            deviceSession = getDeviceSession(channel, remoteAddress, String.valueOf(deviceId));
+            position.setDeviceId(deviceSession.getDeviceId());
+
+            if (channel != null) {
+                sendResponse(channel, serviceId, requestId);
+            }
+
+            position.set(Position.KEY_RESULT, String.valueOf(NPH_SGC_RESULT));
+            position.setTime(new Date());
+            getLastLocation(position, new Date());
+            position.setValid(false);
+
+            return position;
+
+        }
+
+        if (serviceId == NPH_SRV_NAVDATA) {
+
+            deviceSession = getDeviceSession(channel, remoteAddress);
+            if (deviceSession == null) {
+                return null;
+            }
+
+            Position position = new Position(getProtocolName());
+            position.setDeviceId(deviceSession.getDeviceId());
+
+            if (channel != null) {
+                sendResponse(channel, serviceId, requestId);
+            }
+
+            decodeData(buf, position);
+
+            return position;
+        }
+
+        return null;
+    }
+
+}
diff --git a/src/main/java/org/traccar/protocol/NdtpV6ProtocolEncoder.java b/src/main/java/org/traccar/protocol/NdtpV6ProtocolEncoder.java
new file mode 100644
index 000000000..7aac8658a
--- /dev/null
+++ b/src/main/java/org/traccar/protocol/NdtpV6ProtocolEncoder.java
@@ -0,0 +1,42 @@
+/*
+ * Copyright 2022 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 org.traccar.BaseProtocolEncoder;
+import org.traccar.Protocol;
+import org.traccar.model.Command;
+
+public class NdtpV6ProtocolEncoder extends BaseProtocolEncoder {
+
+    public NdtpV6ProtocolEncoder(Protocol protocol) {
+        super(protocol);
+    }
+
+    @Override
+    protected Object encodeCommand(Command command) {
+        switch (command.getType()) {
+            case Command.TYPE_IDENTIFICATION:
+                return "BB+IDNT";
+            case Command.TYPE_REBOOT_DEVICE:
+                return "BB+RESET";
+            case Command.TYPE_POSITION_SINGLE:
+                return "BB+RRCD";
+            default:
+                return null;
+        }
+    }
+
+}