- UNSUBACK 數據包由服務器發送到客戶端以確認收到 UNSUBSCRIBE 數據包。
- 該數據包不包含Payload，所以剩餘長度爲2，即2字節的可變包頭長度。
1. 固定包頭 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. 可變包頭 Variable header
|
Bit |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0 |
|
byte 1 |
Packet Identifier MSB |
|||||||
|
byte 2 |
Packet Identifier LSB |
|||||||