Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

IP/TV flooding multicast

We have two Ip/TV boxes and they are just constantly flooding the local subnet with thousands of multicast packets. I wouldnt assume that would be the normal operation as this takes up a lot of bandwidth. Does anyone have an idea of the problem?

Hall of Fame Super Silver

Re: IP/TV flooding multicast


Depending on which IPTV boxes they are and how they are configured, it is likely that the multicast that you are seeing IS normal operation. In normal operation each program that is configured on the IPTV server and that is active sends the audio signal for that program on one multicast address and sends the video signal for that program on another multicast address.

That may amount to a significant amount of multicast on the local subnet. Depending on where clients are located that have requested any of these programs the multicast will be forwarded from the subnet where it originates to the subnet where the client receiver is located. The advantage of using multicast is that the first receiver to request the program will generate the particular amount of multicast traffic, but any other receivers on that subnet will also receive the program with zero additional bandwidth requirement.



New Member

Re: IP/TV flooding multicast

What do you mean by "flooding?" Do you mean it is being broadcasted and every switchport is being hit with traffic? If that is the case, you have some multicast leaks in your network and you need to enable igmp snooping on your switches and such. Switch ports should only receive multicast traffic if they subscribe to the group.

CreatePlease login to create content