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question about PIM-SM and PIM-SSM

hi folks,

my topology is like this:

Source - R1 - R2 - R3 - Host

R1 has support for SSM and PIM-SM

R2 has support for SSM and PIM-SM

R3 has support for PIM-SM and IGMPv2 only

Host today uses IGMPv2, but IGMPv3 is coming soon

My focus is to have, as last step, a SSM-IGMPv3 infrastructure. But today I couldn't.

How to create a solution that could be simple to migrate from PIM-SM to SSM?

First of all, I think, I've to assign a 232.x.x.x range for multicast groups, is it? Then I've to implement a PIM-SM solution, whit RP, ... or maybe I could use SSM on R1-R2, and SM on R3?

Any advice will be appreciated




Re: question about PIM-SM and PIM-SSM

I thinks IGMP v3 is backward compatible with IGMP v2 and IGMP v1.

IGMP v1 and V2 cannoe coexists with each other


New Member

Re: question about PIM-SM and PIM-SSM

Let's look at your reasons for wanting to use SSM in the first place... are you ever going to have more than one sender? Will there ever be a time when your hosts will be running IGMPv3 and want to restrict from which of those sender's they prefer the Mcast stream?

If the answer is no to any of the above, then you are ok with just igmpv2 and sm. I would spend more time worrying about AUTO-RP vs BSR there are many discrete differences in a large network to the two. I personally am a big fan of BSR and built my network using it.

Also there are other things coming such as MSDP/anycast that are far more likely to be widely implemented instead of SSM. check into those...