Dell 6200 SERIES manual Example #2 Configuring DiffServ VoIP Support, 148

Example #2: Configuring DiffServ VoIP Support

Enter Global Config mode. Set queue 6 on all ports to use strict priority mode. This queue shall be used for all VoIP packets. Activate DiffServ for the switch.

console#config cos-queue strict 6 diffserv

Create a DiffServ classifier named class_voip and define a single match criterion to detect UDP packets. The class type match-all indicates that all match criteria defined for the class must be satisfied in order for a packet to be considered a match.

class-map match-all class_voip match protocol udp

exit

Create a second DiffServ classifier named class_ef and define a single match criterion to detect a DiffServ code point (DSCP) of EF (expedited forwarding). This handles incoming traffic that was previously marked as expedited elsewhere in the network.

class-map match-all class_ef match ip dscp ef

exit

Create a DiffServ policy for inbound traffic named pol_voip, then add the previously created classes 'class_ef' and 'class_voip' as instances within this policy.

This policy handles incoming packets already marked with a DSCP value of EF (per class_ef definition), or marks UDP packets per the class_voip definition) with a DSCP value of EF. In each case, the matching packets are assigned internally to use queue 6 of the egress port to which they are forwarded.

policy-map pol_voip in class class_ef assign-queue 5 exit

class class_voip mark ip-dscp ef assign-queue 5 exit

exit

Attach the defined policy to an inbound service interface.

interface ethernet 1/g1 service-policy in pol_voip

exit exit

148

Quality of Service