Cisco Cisco Aironet 350 Mini-PCI Wireless LAN Client Adapter Guide De Conception

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5-8
Enterprise Mobility 4.1 Design Guide
OL-14435-01
Chapter 5      Cisco Unified Wireless QoS
  Wi-Fi Multimedia
This classification scheme has eight priorities, which WMM maps to four access categories: AC_BK, 
AC_BE, AC_VI, and AC_VO. These access categories map to the four queues required by a WMM 
device, as shown in 
.
 shows the WMM data frame format. Note that even though WMM maps the eight 802.1P 
classifications to four access categories, the 802.11D classification is sent in the frame.
Note
The WMM and IEEE 802.11e classifications are different from the classifications recommended and 
used in the Cisco network, which are based on IETF recommendations. The primary difference in 
classification is the changing of voice and video traffic to 5 and 4, respectively. This allows the 
6 classification to be used for Layer 3 network control. To be compliant with both standards, the Cisco 
Unified Wireless solution performs a conversion between the various classification standards when the 
traffic crosses the wireless-wired boundary.
Figure 5-6
WMM Frame Format
Table 5-2
Table 2 802.1P and WMM Classification
Priority
802.1P Priority
802.1P Designation
Access Category
WMM Designation
Lowest
1
BK
AC_BK
Background
2
-
0
BE
AC_BE
Best Effort
3
EE
4
CL
AC_VI
Video
5
VI
6
VO
AC_VO
Voice
Highest
7
NC
132599
Frame
control
Dur
A1
A2
A3
A4
Seq
control
QoS
control
Body
FCS
2
2
6
6
6
2
0  or  6
0  or  2
n
4
0
ack
policy
EOSP
0
UP
15-7
6-5
4
3
2-0
Acknowledge ------- 00
Do not acknowledge ------- 01
End of service
period
802.1D
priority