Re: Overlapping Routes

Dave Katz <dkatz@JUNIPER.NET> Fri, 15 April 2005 19:19 UTC

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Date: Fri, 15 Apr 2005 12:19:05 -0700
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From: Dave Katz <dkatz@JUNIPER.NET>
Subject: Re: Overlapping Routes
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On Apr 15, 2005, at 2:22 AM, Tom Petch wrote:

> Agree with everything Dave saids but would stress that OSPF by design 
> does not
> cater for overlapping prefix (from the same router) so a router MUST 
> NOT
> originate two LSA, one a /24 and the other a /28 for the same prefix.  
> Other
> routing protocols are different which is an issue when redistributing 
> from them
> into OSPF.

Do not confuse the encoding of the LSA IDs with the concept of 
advertising overlapping routes.  It is perfectly reasonable to 
advertise overlapping routes, if not necessarily too useful.  In fact, 
all the gorp in appendix E is to specifically support overlapping 
routes (because of the screwed up LSA ID encoding.)

--Dave

Zhao-Yang Dong
Dave Katz
Tom Petch
OSPF LSID with vary length masks Acee Lindem
Re: LSIDs with vary length masks Acee Lindem
Re: OSPF LSID with vary length masks Acee Lindem
Re: OSPF LSID with vary length masks Acee Lindem
Re: OSPF LSID with vary length masks Acee Lindem
Re: Overlapping Routes Dave Katz