No Subject

  At the end of phase 2, traffic will be flowing natively from S along a
  source-specific tree to the RP, and from there along the shared tree to
  the receivers.  Where the two trees intersect, traffic may transfer from
  the source-specific tree to the RP tree, and so avoid taking a long
  detour via the RP.

and 

  All of these problems are caused by there being more than one upstream
  router with join state for the group or source-group pair.  PIM does not
  prevent such duplicate joins from occurring - instead when duplicate
  data packets appear on the LAN from different routers, these routers
  notice this, and then elect a single forwarder.  This election is
  performed using PIM Assert messages, which resolve the problem in favor
  of the upstream router which has (S,G) state, or if neither or both
  router has (S,G) state, then in favor of the router with the best metric
  to the RP for RP trees, or the best metric to the source to source-
  specific trees.


I BELIEVE that if there is both (S,G) and (*,G) forwarding state,
that the (S,G) list is searched first and then the (*,G) is used only if
there is no (S,G) match, but I cannot (as I wait for the turkey to cook)
find any documentation that confirms this.

                                   Regards
                                   Marshall Eubanks


   Multicast Technologies, Inc.
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