- UNSUBACK 数据包由服务器发送到客户端以确认收到 UNSUBSCRIBE 数据包。
- 该数据包不包含Payload，所以剩余长度为2，即2字节的可变包头长度。
1. 固定包头 Fixed header
|
Bit |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0 |
|
byte 1 |
MQTT Control Packet type (11) |
Reserved |
||||||
|
|
1 |
0 |
1 |
1 |
0 |
0 |
0 |
0 |
|
byte 2 |
Remaining Length (2) |
|||||||
|
|
0 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
2. 可变包头 Variable header
|
Bit |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0 |
|
byte 1 |
Packet Identifier MSB |
|||||||
|
byte 2 |
Packet Identifier LSB |
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