QoS for Video conferencing

[ja raju]

Hi guys,

I'm having some issues with classifying video conference traffic for QoS on our WAN link.

This is the config i'm using: (partial)

class-map match-any VIDEO

match protocol rtp video

policy-map QoS-Policy

class VIDEO

    bandwidth 1024

  set ip dscp cs5

policy-map WAN-10M

class class-default

    shape average 10485760

  service-policy QoS-Policy

interface GigabitEthernet0/0

bandwidth 10000

ip address <ip> 255.255.255.252

ip nbar protocol-discovery

ip flow ingress

load-interval 30

duplex full

speed 100

media-type rj45

service-policy output WAN-10M

Then I got the users to test making video calls from their Cisco phones to a remote site via the WAN link but I don't see any packets matching the VIDEO class.

wanrtr#sh policy-map int g0/0 output class VIDEO

GigabitEthernet0/0

  Service-policy output: WAN-10M

    Class-map: VIDEO (match-any)

      0 packets, 0 bytes

      30 second offered rate 0 bps, drop rate 0 bps

      Match: protocol rtp video

        0 packets, 0 bytes

        30 second rate 0 bps

          Queueing

          queue limit 64 packets

          (queue depth/total drops/no-buffer drops) 0/0/0

          (pkts output/bytes output) 0/0

          bandwidth 1024 kbps

      QoS Set

        dscp cs5

          Packets marked 0

Any idea why there's no match on rtp video?

Thanks in advance.

[John Blakley]

Does nbar show matches on rtp video?

show ip nbar protocol-discovery

If it's not showing video there, then you may not be marking those packets like that. I don't have Cisco phones in our environment (that do video as well). Is there a way that you can match on the specific subnet and cs marking that the phone provides instead of using nbar? And as a side note I believe video should generally be marked to CS4 instead of 5 so it doesn't crossover into your voice traffic.

[ja raju]

I only see "rtp". It does not specify whether it's rtp-video, audio, etc. If there's no way around this, I would need to use ACL to mark the traffic instead. Yea I think I'm going to mark video as cs4 instead of cs5, thanks for that

wanrtr#show ip nbar protocol-discovery

GigabitEthernet0/0

Last clearing of "show ip nbar protocol-discovery" counters 3d19h

                            Input                    Output                 

                            -----                    ------                 

   Protocol                 Packet Count             Packet Count           

                            Byte Count               Byte Count             

                            30sec Bit Rate (bps)     30sec Bit Rate (bps)   

                            30sec Max Bit Rate (bps) 30sec Max Bit Rate (bps)

   ------------------------ ------------------------ ------------------------

   rtp                      11242371                 25957872               

                            2247292882               3607790125             

                            649000                   731000                 

                            2471000                  2166000