336
C
HAPTER
16: C
ONFIGURING
Q
UALITY
OF
S
ERVICE
WMM QoS on the WX Switch
MSS performs classification on ingress to determine a packet’s CoS value.
This CoS value is used to mark the packet at the egress interface.
The classification and marking performed by the switch depend on
whether the ingress interface has an 802.1p or DSCP value other than 0,
and whether the egress interface is tagged or is an IP tunnel.
The mappings between DSCP and CoS values are configurable. (See
“Changing CoS Mappings” on page 344.) 802.1p and CoS values map
directly and are not configurable. DSCP 0 of the DSCP-to-CoS map is
reserved. 802.1p determines CoS for packets with DSCP 0. CoS 0 of the
CoS-to-DSCP map is also reserved. CoS 0 packets are marked with DSCP 0.
Table 27 shows how WMM priority information is mapped across the
network. When WMM is enabled, 3Com switches and MAPs perform
these mappings automatically.
You can use static CoS to assign the same CoS value to all packets for a
specific SSID. The static CoS value is assigned on the MAP, in both traffic
directions (from the client to the WX and from the WX to the client). (For
information, see “Configuring Static CoS” on page 343.)
Table 27
WMM Priority Mappings
Service
Type
IP Precedence IP ToS
DSCP
802.1p
CoS
MAP
Forwarding
Queue
0
0
0
0
0
0
Background
3
3
0x60
24
3
3
1
1
0x20
8
1
1
Best Effort
2
2
0x40
16
2
2
4
4
0x80
32
4
4
Video
5
5
0xa0
40
5
5
6
6
0xc0
48
6
6
Voice
7
7
0xe0
56
7
7
Summary of Contents for 3CRWX120695A
Page 138: ...138 CHAPTER 6 CONFIGURING AND MANAGING IP INTERFACES AND SERVICES ...
Page 272: ...272 CHAPTER 11 CONFIGURING RF LOAD BALANCING FOR MAPS ...
Page 310: ...310 CHAPTER 13 CONFIGURING USER ENCRYPTION ...
Page 322: ...322 CHAPTER 14 CONFIGURING RF AUTO TUNING ...
Page 350: ...350 CHAPTER 16 CONFIGURING QUALITY OF SERVICE ...
Page 368: ...368 CHAPTER 17 CONFIGURING AND MANAGING SPANNING TREE PROTOCOL ...
Page 412: ...412 CHAPTER 19 CONFIGURING AND MANAGING SECURITY ACLS ...
Page 518: ...518 CHAPTER 21 CONFIGURING AAA FOR NETWORK USERS ...
Page 530: ...530 CHAPTER 22 CONFIGURING COMMUNICATION WITH RADIUS ...
Page 542: ...542 CHAPTER 23 MANAGING 802 1X ON THE WX SWITCH ...
Page 598: ...598 CHAPTER 26 ROGUE DETECTION AND COUNTERMEASURES ...
Page 706: ...706 GLOSSARY ...