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Re: [babel] info-model: calculated and received metrics

Juliusz Chroboczek <jch@irif.fr> Fri, 26 April 2019 10:22 UTC

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Date: Fri, 26 Apr 2019 12:22:50 +0200
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From: Juliusz Chroboczek <jch@irif.fr>
To: "STARK, BARBARA H" <bs7652@att.com>
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Subject: Re: [babel] info-model: calculated and received metrics
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> This was discussed in Prague, but I think it still didn't come to the right conclusion (in my head) as I look at it again.
>> From reading rfc6126bis, it appears that 
>  - all routes advertised by neighbors will have a received metric
>  - all routes advertised by this router will have a calculated metric
>  - routes originated by this router will not have a received metric
>  - routes with infinite received metrics don't need a calculated metric

In the last case -- the calculated metric will necessarily be infinite.

> For a route to exist in the info model babel-routes object, either the
> received or calculated metric MUST be non-zero (rfc6126bis only mentions
> the received metric as being in its route table).

Zero is a perfectly fine value for a metric (actually, the very best).
Perhaps you meant defined instead of non-zero?

-- Juliusz

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