Subject: [pim] PIM-SM: Can RPF checks in lost_assert macros be omitted?

From: Mark Doll <[email-masked]>
Date: Fri, 17 Sep 2004 15:19:53 +0200

Hi PIM folks!

What would happen, if RPF checks in the lost_assert macros would be 
omitted? As a consequence, there would be only a lost_assert(*,G,I) and 
a lost_assert(S,G,I) and no lost_assert(S,G,rpt,I) any more, since the 
difference between the (S,G,I) and (S,G,rpt,I) version is only a 
different RFC check.

ColdAssert and AssertTrackingDesired explicitly incorporate an 
approprate RPF check, so they don't need it in lost_assert. Also the 
data forwarding rule does it's own RPF check, so it's not nececessy 
there either.

The reason for omitting the RFC check is, that this presumably 
superfluous check can cause two routers to simultaneously forward the 
same traffic on a shared LAN, as Venu correctly pointed out.

Or am I simply too blind to see the apparentness of my mistake here?

- Mark.

_______________________________________________
pim mailing list
[email-masked]
https://www1.ietf.org/mailman/listinfo/pim