I was going through the MVPN concepts. As per my understanding, the draft rosen 6 was PIM ASM based, in which
- The provider core uses PIM ASM and thus we need to connfigure an RP, to which all PE's in the network will send a PIM join. The Group for which the join would be sent should be same since this group would be used in the Default MDT.
- If the source wants to switch to the Data MDT, then it would send a special UDP message via the default MDT so that all the PE's would recevive it. This message would have the Group address to which the source would now send the data. All the interested PE's will now send a PIM join to the source PE and thus data would start flowing on the Data-MDT instead of Default MDT.
- Now When we say the core network is PIM-SSM based, why do we need to configure the RP?
- As per my understading, now there will be BGP messages which will help in autodiscovery of the PE's and now the PE's can send a join directly to the PE. What is the need of the RP here in case on PIM-SSM ?