Which router should RP be configured at?

[wfqk]

Hi, Do you think this is important which router should RP be configured at? 

As we know, after RPT established, it will switch to SPT. And we can also control traffic at RT. Once it exceed the threashold, it could be switched to SPT. Do you think so? Thank you. 

[Austin Sabio]

This is just my opinion, I would use a protocol for such task auto-rp or bsr and leave the selection process of rp to the protocol algorithm itself. 

Please see 

https://www.cisco.com/c/en/us/products/collateral/ios-nx-os-software/ip-multicast/whitepaper_c11-508498.html

http://packetlife.net/blog/2008/oct/20/pim-sm-source-versus-shared-trees/

I hope this helps and good luck!

-Austin

[wfqk]

we have several protocols to configure RP, but do we have some rules to let us choose which router configured as RP is best? For example choosing the router located in the middle between server and reciver

[Austin Sabio · Accepted solution]

According to cisco documentations, here's what I found.

Designing PIM Rendezvous Point

The following sections discuss best practices in designing and deploying the PIM-SM Rendezvous Point.

PIM-SM RP Placement

It is assumed that each medium enterprise site has a wide range of local multicast sources in the data center for distributed medium enterprise IT-managed media and employee research and development applications. In such a distributed multicast network design, Cisco recommends deploying PIM RP on each site for wired or wireless multicast receivers and sources to join and register at the closest RP. The Medium Enterprise Reference design recommends PIM-SM RP placement on a VSS-enabled and single resilient core system in the three-tier campus design, and on the collapsed core/distribution system in the two-tier campus design model. See Figure 2-43.

Figure 2-43 Distributed PIM-SM RP Placement

https://www.cisco.com/c/en/us/td/docs/solutions/Enterprise/Medium_Enterprise_Design_Profile/MEDP/chap2.html#wpxref61810

Study case:

PIM-SM RP Placement Best Practices

It is assumed that each community college site has a wide range of local multicast sources in the data center for distributed community college IT-managed media and student research and development applications. In such a distributed multicast network design, Cisco recommends deploying PIM RP on each site for wired or wireless multicast receivers and sources to join and register at the closest RP. The community college reference design recommends PIM-SM RP placement on a VSS-enabled and single resilient core system in the three-tier campus design, or on the collapsed core/distribution system in the two-tier campus design model.

https://www.cisco.com/c/en/us/td/docs/solutions/Enterprise/Education/CCVE/CCVE_DG/CCVE_Ch3.html

I hope this helps. Please don't forget to mark the correct answer to benefit others. 

Good luck! 

- Austin

[wfqk]

Thank you Austin!

[Austin Sabio]

My pleasure. Thanks for the rating. 

-Austin