Subject: [pim] RP map problem - BSR

From: "Katta Sambasivarao" <[email-masked]>
Date: 8 Jan 2002 12:54:39 -0000

hi,
I have a doubt about using RP-set info received in 
BSR message.

Section 3.4 of BSR draft talks about checking for new RPs and missing old RPs in BSR message for J/P states this router got.

Suppose I received a BSR message with RP1 and RP2 for group (G/32) and RP1 priority is more than RP2.

Now I select RP1 as RP for group G. Now in later BSR message, suppose that the priority of RP1 is less than RP2. 
From the draft(sec 3.4), I understood that RP priority is used only in tie breaking. Once we selcted RP we will not change until that RP becomes un-available or new RP becomes available. So the change in priority like in above case will not affect the existing states. 

But will that not lead to problem. A router that booted late and received 2nd BSR message will map G to RP2 while this router will use RP1 for G.

I think, Section 3.4 should address the change in RP priority case also. A router should check for correctness of old RP mappings as per new BSR message.

Please correct me, if my understanding is not correct.

Thanks in advance.

regards,
Katta