QOS and Multicast

[bill.greenwood]

I am looking at setting up Multicast for corporate communications, primarily audio and video. We will be using dense-sparce-mode and restricting traffic based on the group either on a location, region, or global basis. My question is on QOS; how do I provide appropriate levels of service to these applications. I can rate-limit and used admin-scoping to contain the traffic, but how do I prioritize this traffic with something like LLQ. We currently use LLQ to prioritize traffic across our WAN.

[Georg Pauwen]

Hello Bill,

depending on which multicast groups you are using, you could configure the following (in this example, access list 1 allows all multicast traffic):

class-map MULTICAST

match access-group 1

!

policy-map MULTICAST_WAN

class MULTICAST

priority 100

!

interface serial0

service-policy output MULTICAST_WAN

access-list 1 permit 224.0.0.0 15.255.255.255

HTH,

Georg

[bill.greenwood]

Georg,

If I understand correctly, classifing multicast is no different from any other traffic. Am I correct?

How does this work with the ability to rate limit this traffic with the IP MULTICAST RATE-LIMIT (either on a group or interface)? I would guess that I could have "high" priority voice multicast traffic would be dropped if it exceeds the rate-limit.

Bill

[thisisshanky]

You can definitely rate-limit traffic, which is a very useful tool, but usually delay sensitive traffic such as video streams do not like rate-limiting which drops packets which is not really good for video.