Web Management Guide-R05

Chapter 9 | Class of Service
Layer 3/4 Priority Settings
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Figure 137: Mapping CoS Values to Egress Queues
To show the internal PHB to hardware queue map:
1. Click Traffic, Priority, PHB to Queue.
2. Select Show from the Action list.
3. Select an interface.
Figure 138: Showing CoS Values to Egress Queue Mapping
Layer 3/4 Priority Settings
Mapping Layer 3/4 Priorities to CoS Values
The switch supports several common methods of prioritizing layer 3/4 traffic to
meet application requirements. Traffic priorities can be specified in the IP header of
a frame, using the priority bits in the Type of Service (ToS) octet, or the number of
the TCP/UDP port. If priority bits are used, the ToS octet may contain three bits for
IP Precedence or six bits for Differentiated Services Code Point (DSCP) service.
When these services are enabled, the priorities are mapped to a Class of Service
value by the switch, and the traffic then sent to the corresponding output queue.