draft-ietf-grow-simple-va-04 needs another deployment consideration.

Routes in the RIB (not the FIB) are sometimes used
to resolve BGP nexthops and nexthops for static routes.

There is a rule not to resolve such nexthops using the default
route. If routes are removed from the RIB, they will no
longer be able to resolve nexthops. Also, when resolving
nexthops, the resolving routes sometimes carry attributes
that are important to the resolving process. If the
default route is used to resolve nexthops, such attributes
would be lost. Examples of such attributes are
IGP distance (it may be the same as the default) and
whether it is on a tunnel.

The reason for that rule is this:
A non default route says: I can reach the advertised
network and all IP addresses covered by it. If any
IP address covered by this prefix is unreachable,
then it doesn't exist.
A default route says: I can reach many IP addresses,
but obviously not all of them. I can not tell you
which I can actually reach and which I can't.

Routes in the RIB may also be redistributed to other
protocols. If they no longer exist in the RIB, they
will not be redistributed.

These considerations do not break the technique,
but they need to be stated.

--
Jakob Heitz.

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Ronald 
Bonica
Sent: Monday, April 30, 2012 9:52 AM
To: [email protected]
Cc: [email protected]; [email protected]
Subject: Re: [GROW] draft-ietf-grow-simple-va

Robert,

This sounds reasonable to me. Please issue a new version of the draft, as the 
current version has expired. When you issue a new version, change the filename, 
so that it won't look like a WG submission. Also, ping me so that I can send 
the document on for IETF Last Call.

                                                             Ron

> -----Original Message-----
> From: Robert Raszuk [mailto:[email protected]]
> Sent: Monday, April 30, 2012 1:49 AM
> To: Ronald Bonica
> Cc: [email protected]; [email protected]
> Subject: Re: [GROW] draft-ietf-grow-simple-va
> 
> Ron,
> 
> >> So, how do we proceed? If you want to demonstrate WG support of
>  >> draft-ietf-grow-simple-va, let the WG LC proceed. If you want to
> >> publish without demonstrating WG support, I would be glad to AD
> >> sponsor that draft.
> 
> Please proceed with AD sponsorship on this draft.
> 
> In my view the idea and the draft have already received sufficient
> support within this group, other IETF and IRTF groups as well as
> outside of IETF in various public forums.
> 
> Thx,
> R.
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