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CLI – The following example shows how to assign WRR weights
of 1, 4, 16 and 64 to the CoS priority queues 0, 1, 2 and 3.

Mapping Layer 3/4 Priorities to CoS Values

This switch supports a common method 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. 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.
Because different priority information may be contained in the
traffic, this switch maps priority values to the output queues in the
following manner:
• The precedence for priority mapping is IP Precedence or DSCP
Priority and then Default Port Priority.
• IP Precedence and DSCP Priority cannot both be enabled.
Enabling one of these priority types will automatically disable
the other.
• IP Precedence and DSCP Priority settings are global and apply
to all ports on the switch.
Console(config)#queue bandwidth 1 4 16 64 3-162
Console(config)#exit
Console#show queue bandwidth 3-165
Queue ID Weight
-------- ------
0 1
1 4
2 16
3 64
Console#
b_mgmt.book Page 93 Tuesday, July 8, 2003 5:24 PM