OSPF : Summarization of type-7 lsa's

tajay <tajay@NETD.COM> Tue, 05 July 2005 04:24 UTC

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From: tajay <tajay@NETD.COM>
Subject: OSPF : Summarization of type-7 lsa's
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hi guys,
I have some doubts and queries in NSSA. Whenever we use summarization in 
 OSPF we generate only one type-5  lsa for all type-7 lsa's which falls 
under configured summary address.

Now As per RFC 1587 / 3101  " The path type should always be set to the 
highest path type that is subsumed by the net range."

Metric depends on path type ,

    1> If path type selected is external type 2 then type 5 metric 
should be set to the largest type-7 metric subsumed by this net range + 1 ;

****** I have doubt like.. why we add 1 in this cost ..Is there any 
specific reason behind this?

 2> If the path type selected in external type 1 , the type -5 metric 
should be set to the largest metric..

***  In this case we don't add any cost to ASBR. why this is so?

Can any one please give me guideline.

with regards