Cisco Systems 2960 Configuring Ingress Queue Characteristics

29-57
Catalyst 2960 Switch SoftwareConfiguration Guide
78-16881-01
Chapter29 Configuring QoS
Configuring Standard QoS
Note In the above DSCP-to-DSCP-mutation map, the mutated values are shown in the body of the matrix. The
d1 column specifies the most-significant digit of the original DSCP; the d2 row specifies the
least-significant digit of the original DSCP. The intersection of the d1 and d2 values provides the mutated
value. For example, a DSCP value of 12 corresponds to a mutated value of 10.
Configuring Ingress Queue Characteristics
Depending on the complexity of your network and your QoS solution, you might need to perform all of
the tasks in the next sections. You will need to make decisions about these characteristics:
•Which packets are assigned (by DSCP or CoS value) to each queue?
•What drop percentage thresholds apply to each queue, and which CoS or DSCP values map to each
threshold?
•How much of the available buffer space is allocated between the queues?
•How much of the available bandwidth is allocated between the queues?
•Is there traffic (such as voice) that should be given high priority?
These sections contain this configuration information:
•Mapping DSCP or CoS Values to an Ingress Queue and Setting WTD Thresholds, page 29-57
(optional)
•Allocating Buffer Space Between the Ingress Queues, page 29- 59 (optional)
•Allocating Bandwidth Between the Ingress Queues, page 29-60 (optional)
•Configuring the Ingress Priority Queue, page 29-61 (option al)
Mapping DSCP or CoS Values to an Ingress Queue and Setting WTD Thresholds
You can prioritize traffic by placing packets with particular DSCPs or CoSs into certain queues and
adjusting the queue thresholds so that packets with lower priorities are dropped.
Beginning in privileged EXEC mode, follow these steps to map DSCP or CoS values to an ingress queue
and to set WTD thresholds. This procedure is optional.