Re: router-router NHRP

[Yakov Rekhter <[e-mail]>]

Dimitry,

> > Consider a router X within an OSPF domain, ASBR Y of that domain, and
> > router Z (outside of the OSPF domain) that peers with Y using BGP.  Z
> > advertises to Y a route to some destination D, and puts its own address
> > as the next hop. Y injects this route into OSPF.  When X originates an
> > NHRP Request for D, and the Request reaches Y, Y has a route to D, but
> > the next hop on this route is not Y, but Z. Y returns Z as the next hop
> > in the NHRP Reply. Since Y certainly sees any changes in this route, Y
> > would be able to send to X a Purge message once Y notices the changes.
> > 
> 
> Good.  But there is no text in your proposal that requires a proxy router tha
t
> replied with a third party address to send a Purge message to the originator
> of the shortcut.  The proposal should be clear on that since there are
> certain implications of such a requirement, e.g. the amount of state that nee
d
> to be saved at a proxy router, especially if such a router is a proxy for
> a good number of edge forwarders.

The text of my proposal certainly could be improved.

Yakov.