Re: [Idr] IETF LC for IDR-ish document <draft-ietf-grow-bgp-reject-05.txt> (Default EBGP Route Propagation Behavior Without Policies) to Proposed Standard

Job Snijders <> Thu, 20 April 2017 15:41 UTC

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Date: Thu, 20 Apr 2017 17:41:42 +0200
From: Job Snijders <>
To: Enke Chen <>
Cc: Jared Mauch <>, Hares Susan <>,
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Subject: Re: [Idr] IETF LC for IDR-ish document <draft-ietf-grow-bgp-reject-05.txt> (Default EBGP Route Propagation Behavior Without Policies) to Proposed Standard
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On Thu, Apr 20, 2017 at 08:36:17AM -0700, Enke Chen wrote:
> If it is not obvious, let me state the I participate in IDR WG as an
> individual contributor, just like you do I suppose.
> Let me rephrase what I said, for a code base with a large and diverse
> customer base I do not foresee any possibility for the default
> behavior change in this case. Again please treat it as my personal
> opinion.
> I am certainly aware of other cases where the default behavior has
> been changed. But this one is different.  This case seems similar to
> the default behavior ("permit" or "deny") for an empty ACL.  Once the
> "permit" or "deny" is set in the code and is widely deployed for a
> long time, it is just not possible to make the switch between "permit"
> and "deny".

You say "it is not possible", however there are examples where it turned
out to be possible. At least one implementer confirmed on this list that
they plan to change their default.

Perhaps, "impossible" should be phrased as "unwilling".

Kind regards,