Re: LC Comments on "considerations" scaling analysis

[Robert Raszuk <raszuk at cisco.com>]

Hi Thomas,

> And a last call by IDR too for the BGP part ?

As a matter of fact that would be indeed a great suggestion.

There are changes defined in the spec which silently modify the route 
reflection behaviour as specified in RFC4456. Those need to be clarified.

Example from draft-ietf-l3vpn-mvpn-considerations-03:

      "Using plain BGP route selection procedures,
      the route reflector will withdraw a C-multicast Source Tree Join
      for a said (C-S,C-G) when there is no PE advertising one anymore."

Quote from RFC4456:

   "When an RR receives a route from an IBGP peer, it selects the best
   path based on its path selection rule.  After the best path is
   selected, it must do the following depending on the type of peer it
   is receiving the best path from

      1) A route from a Non-Client IBGP peer:

         Reflect to all the Clients.

      2) A route from a Client peer:

         Reflect to all the Non-Client peers and also to the Client
         peers."

Therefor in "plain BGP" we advertise best path and withdraw best paths 
or replace them with implicit withdraw. And you may have changes to 
C-multicast best path each time you receive one from any PE or best path 
owner PE withdraws one.

Cheers,
R.