Step1. Configure the QoS on the End device


1.  Configure the Access-list to identify the type of traffic

CME2(config)#access-list 100 permit udp range 8766 35000 any range 8766 35000

2. Create a class-map and associate the access-group with it.

CME2(config)#class-map RTP_SUBNET_192_168_255   

CME2(config-cmap)#match access-group 100


3. Create a policy map and set the DSCP value for the VOIP RTP traffic. Then apply it to the inbound traffic of the interface FastEthernet 1/0:

CME2(config)#policy-map Set-EF-PHB-RTP-192-168-255

CME2(config-pmap)#class RTP_SUBNET_192_168_255

CME2(config-pmap-c)#set dscp ef


CME2(config)#int fa1/0

CME2(config-if)#service-policy input Set-EF-PHB-RTP-192-168-255

After the end devices have set CoS or ToS values, the switch has the option of trusting them.