RE: OSPF Multipoint

On ti, jul 12, 2011 at 21:41:30, Joe Astorino wrote:
> Cc: Cisco certification
> Subject: Re: OSPF Multipoint
>
> Another way to think about it is that OSPF p2m treats connections as
> individual point-to-point links. As such, each router advertises a /32
> host route and actually suppresses the advertisement of the broader
> network route
>

Joe explains it very well. The underlying reason to use it is that your
layer2 topology does not match your layer3 topology. Think NBMA hub&spoke
where spokes don't have PVCs to each other. The normal behavior would be to
not change the next-hop since they are connected to same network and this
would break l3 connectivity.

/Daniel

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Received on Tue Jul 12 2011 - 22:25:18 ART