Re: Two queries on calculating AS external routes

"Pat Murphy - (650)329-4044" <pmurphy@omega7.wr.usgs.gov> Thu, 07 July 2005 15:10 UTC

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Date: Thu, 07 Jul 2005 08:13:19 -0700
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From: "Pat Murphy - (650)329-4044" <pmurphy@omega7.wr.usgs.gov>
Subject: Re: Two queries on calculating AS external routes
To: OSPF@PEACH.EASE.LSOFT.COM
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Paresh,

>In my case below, what if the two LSAs are not quite
>functoinally equivalent i.e what if the LSAs have the same
>destination, same cost etc but have different non-zero
>forwarding addresses ? What happens then ?  Do the same
>tie-breaker rules apply or will it be implementation-dependent ?

The tie breaker rules are not applied. Here the installation 
decision process is the same regardless of whether it is 
comparing two Type 5 LSAs, or a Type 5 and a Type 7 LSA, or two 
Type 7 LSAs. Whether or not both are installed depends on the 
pruning done in step (c) as defined in RFC 2328 Section 16.4.1.

Pat