Re: [Isis-wg] [Bier] BAR field length in draft-ietf-bier-isis-extensions and draft-ietf-bier-ospf-extensions

Tony Przygienda <> Wed, 21 February 2018 00:40 UTC

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From: Tony Przygienda <>
Date: Tue, 20 Feb 2018 16:39:31 -0800
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To: IJsbrand Wijnands <>
Cc: "Jeffrey (Zhaohui) Zhang" <>, "" <>, "" <>, "" <>, Eric Rosen <>
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Subject: Re: [Isis-wg] [Bier] BAR field length in draft-ietf-bier-isis-extensions and draft-ietf-bier-ospf-extensions
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> Future specifications may specify BART values that change the
> interpretation of the BARM octet. Those specifications must handle
> backwards
> ICE: This creates a potential dependency which I think we should avoid. I
> think there are possible use-cases where the combination of the two values
> could be valuable. But since we don’t yet know what that is, lets not
> speculate on it. Let keep both values as equal importance without
> interdependency.

And I happen to think that if this proposal has any merit this is precisely
the paragraph we have to keep to make sure that not every possible BART
value is being slaved to IGP Registry Algorithm a.k.a as BARM then ...
Without this section we would be mandating that BARM is always an IGP
algorithm or FA so basically it would mandate IGP Algorithm registry as the
only option to perform a calculation making BART possibly pretty much
useless ... Having a registry being mapped 1:1 into  another registry known
as identity makes them both them the same thing by another name.

So, to get anywhere close to consensus let's get bit less creative maybe
and stick to the four letters of the alphabet that the AD extended as a
wide playing field and the WG seems to converge around ... Or otherwise
stick to option F) unmodified and see who's interested in it unless you
insist on creating an option G) ...


--- tony