Displays current Type-of-Service configuration. In diffserv mode it also shows the current direct 802.1p
assignments and the current DSCP assignments covered later in this section.
For example, an edge switch “A” in an untagged VLAN assigns a DSCP of 000110 on IP packets it receives on
port 6, and handles the packets with high priority (7). When these packets reach interior switch “B” you want
the switch to handle them with the same high priority. To enable this operation, you would configure an
802.1p priority of 7 for packets received with a DSCP of 000110. ToS
diff-services
must be enabled as
shown in the following images.
Figure 30: Viewing the codepoints available for 802.1p priority assignments
Figure 31: ToS configuration that enables both 802.1p priority and DSCP policy assignment
Assigning a DSCP policy on the basis of the DSCP in IPv4 packets received from
upstream devices
The preceding section describes how to forward a policy set by an edge (or upstream) switch. This option
changes a DSCP policy in an IPv4 packet by changing its IP ToS codepoint and applying the priority
associated with the new codepoint. (A DSCP policy consists of a differentiated services codepoint and an
associated 802.1p priority.) You can use this option concurrently with the diffserv 802.1p priority option
(above), as long as the DSCPs specified in the two options do not match.
To use this option to configure a change in policy:
Chapter 8 Quality of Service (QoS): Managing bandwidth
effectively
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