40
Figure 11 802.1Q tag header
Table 10 Description on 802.1p priority
802.1p priority (decimal)
0 000 best-effort
1 001 background
2 010 spare
3 011 excellent-effort
4 100 controlled-load
5 101 video
6 110 voice
7 111 network-management
802.11e priority
To provide QoS services on WLAN, the 802.11e standard was developed. IEEE 802.11e is a
MAC-layer enhancement to IEEE 802.11. IEEE 802.11e adds a 2-byte QoS control field to the
802.11e MAC frame header. The 3-bit QoS control field represents the 802.11e priority in the range
of 0 to 7.
Figure 12 802.11e frame structure
1
0
0
0
0
0
0
1
0 0
0
0 0
0 0
Priority
C
F
I
VLAN ID
TPID(Tag protocol identifier)
TCI(Tag control information)
Byte 1
Byte 2
0
Byte 3
Byte 4
7 5 4 3 2 1 0 7 5 4 3 2 1 06 6 7 5 4 3 2 1 0 7 5 4 3 2 1 06 6
Frame
control
Frame
body
Address
1
Address
2
Address
3
Duration/
ID
Sequence
control
Address
4
2
FCS
2 6 6 2 6 2 4
0~2324
QoS
control
6