Re: [babel] Martin Duke's Discuss on draft-ietf-babel-source-specific-07: (with DISCUSS)

Toke Høiland-Jørgensen <> Thu, 05 November 2020 11:53 UTC

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From: Toke Høiland-Jørgensen <>
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To: Martin Duke <>, The IESG <>
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Date: Thu, 05 Nov 2020 12:53:15 +0100
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Subject: Re: [babel] Martin Duke's Discuss on draft-ietf-babel-source-specific-07: (with DISCUSS)
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Martin Duke via Datatracker <> writes:

> Martin Duke has entered the following ballot position for
> draft-ietf-babel-source-specific-07: Discuss
> When responding, please keep the subject line intact and reply to all
> email addresses included in the To and CC lines. (Feel free to cut this
> introductory paragraph, however.)
> Please refer to
> for more information about IESG DISCUSS and COMMENT positions.
> The document, along with other ballot positions, can be found here:
> ----------------------------------------------------------------------
> ----------------------------------------------------------------------
> I am concerned about the congestion implications of this architecture. If there
> are P prefixes in the network, the number of TLVs exchanged potentially goes
> from P to P^2.
> Perhaps this is an unrealistic use case. But are there any safeguards in the
> protocol against this happening (e.g. limitations on size/freq of updates?) Or
> ought there to be some operational guidance to be somewhat selective about
> source prefixes?

The way it's been used in deployments that I'm aware of, generally only
default routes are distributed with a source prefix, and more specific
routes internally to the network do not have source prefixes. See my
reply to Alvaro for a fuller example: