All things related to multicast

[Jay Ford <>]

On Tue, 18 Mar 2003, Lappa, Joseph wrote:
>    Here are UofPitt, we're running a fairly simple multicast environment
>
> We want make our infrastructure more robust, but still keep it easy to
> debug.  With that in mind...
>
> We're a multi-vender site with Ciscos in the core and a pair of Junipers
> for our border routers.  We run HSRP in many locations with our Ciscos (8
> core 6509s with MSFC running a mix of merged and hybrid code, with going to
> merged soon across campus).  We want to make our multicast routing as
> robust and efficient.
>
>    We are thinking of two possible scenarios:
>
>       1) Make each of our core Cisco 6500s MSDP peers with each other
>          (full mesh), with our Junipers, and configure Anycast-RP with
>          PIM-SM.
>
>       2) Make each of our core Cisco 6500s MSDP peers with each other
>         (full mesh), with our Junipers, and run PIM BSR with PIM-SM.

I have a similar network:
   o  Cisco 6500+MSFC boxes in the core
   o  Cisco 7513 boxes at the border (hopefully becoming Junipers soon)

My current multicast structure has the 2 border boxes acting as the RPs via
static anycast.

> Questions are:
>
>   What is the prefered method these days determining RP?  Anycast-RP or
>   BSR?

I'd say Anycast-RP with static configuration of the RP address.  It's worked
well for me.

>   Are there any problems in running Anycast-RP with HSRP?

I don't do HSRP, so I can't answer that one.

>   How hard is it to debug problems with Anycast-RP vs. PIM BSR?

I haven't had any problems with Anycast-RP.  However, it's just a combination
of MSDP & PIM-SM which are probably already fairly familiar.

>   Will MSDP updates cause a big hit on our 6500 MSFCs?

That depends on your SA rate, but you could just keep the MSDP out of the
core.  I've considered making my core boxes RPs as well, but I'm not sure
there's much point to it.  With the first-packet-triggered cut over to the
shortest path tree, there isn't much downside to having the RPs at the
border.  Do you have a compelling reason for making the core boxes RPs?

________________________________________________________________________
Jay Ford, Network Engineering Group, Information Technology Services
University of Iowa, Iowa City, IA 52242
email: 
,
 phone: 319-335-5555, fax: 319-335-2951