Mapping Layer 3/4 Priorities To Cos Values - SMC Networks 6724AL2 Management Manual

C
ONFIGURING THE
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.
Console(config)#queue bandwidth 1 4 16 64
Console(config)#exit
Console#show queue bandwidth
Queue ID Weight
-------- ------
Console#

Mapping Layer 3/4 Priorities to CoS Values

This 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.
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 Port Priority, 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.
2-138
S
WITCH
0 1
1 4
2 16
3 64
3-191
3-194