Hi, Alex:

    Usually, we only keep the best route to a destination. As you said, at
any time, there may be only one entry for an ASBR with multiple next hops
due to equal-cost multipath. My understanding is that what described in the
RFC is a process to build the best route to an ASBR when you have choice
among multiple routes. It does not mean that an implementation has to keep
all possible routes to an ASBR.

Feng Xie

-----Original Message-----
From: alex lerin [mailto:alexlerinYAHOO.COM]
Sent: Thursday, August 23, 2001 5:43 AM
To: OSPFDISCUSS.MICROSOFT.COM
Subject: About ASExternal calculation

Hi..
I have a doubt in ASExternal Calculation...

  In ASExternal calculations of RFC2328, Section
16.4,3rd point 3rd paragraph,it says that if the
forwarding address is zero,th packet should be sent to
the ASBR itself.Also it says that we have to prune for
multiple entries.
  My doubt is that how can we prune when there is
always only one entry for the ASBR in the routing
table.Because whenever we get a destination ,we check
for its entry in the routing table and compare the
path type etc.,and if thay are equal cost we only add
the next hop entry to the route and not a different
entry.So there is no possibility for multiple entries
for the same ASBR in the routing table.
  If I am wrong tell me when can there be more than
one entries for the same ASBR in the routing table?

  Thanks in advance
  Alex

__________________________________________________
Do You Yahoo!?
Make international calls for as low as $.04/minute with Yahoo! Messenger
http://phonecard.yahoo.com/

• Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]