Re: [Idr] I-D Action: draft-ietf-idr-rs-bfd-02.txt

Randy Bush <randy@psg.com> Mon, 13 March 2017 12:00 UTC

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Date: Mon, 13 Mar 2017 21:00:11 +0900
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Subject: Re: [Idr] I-D Action: draft-ietf-idr-rs-bfd-02.txt
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> Let's observe that the ultimate objective of this draft (and in fact much
> more) can be achieved by assuring that clients receive more then one path
> to given bgp destinations at normal operation.

let's break tradition and actually see what the document says.

Abstract

   When route servers are used, the data plane is not congruent with the
   control plane.  Therefore, the peers on the Internet exchange can
   lose data connectivity without the control plane being aware of it,
   and packets are dropped on the floor.  This document proposes the use
   of BFD between the two peering routers to detect a data plane
   failure, and then uses a newly defined BGP SAFI to signal the state
   of the data link to the route server(s).

and, if you wander over to the referenced route server docco, you'll see
that it already deals with alternate paths.

rady