Re: [Idr] BGP Attribute for Large communities (Attribute 30) was squatted on - Let's get a new attribute number (1 week WG call (10/18 to 10/25)

marco@lamehost.it Wed, 19 October 2016 07:25 UTC

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Cc: IETF IDR WG <idr@ietf.org>, Kristian Larsson <kll@dev.terastrm.net>
Subject: Re: [Idr] BGP Attribute for Large communities (Attribute 30) was squatted on - Let's get a new attribute number (1 week WG call (10/18 to 10/25)
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October 18, 2016 6:06 PM, "Nick Hilliard" <nick@foobar.org>; wrote:

> There is an objective problem here, namely that there is no
> vendor-specific range for path attributes. Given the nature of path
> attribute interpretation, it could be argued that this might be a good
> thing because different vendors will interpret TLVs in different ways,
> which is a potential source of bgp session instability. On the other
> hand, it means that if vendors need to go off and do something new,
> there are no options other than squatting. A vendor-specific range will
> at least contain this problem, so that IANA won't run into the same
> problem in future.
> 

Scary

> On a related issue, it would probably be a good idea to run beacon tests
> with other path attributes to see how they affect reachability, i.e.
> have any other vendors squatted any other path attribute values, and if
> large-communities is moved to 31 or 32, will it suffer the same problem?
> 
> Nick

Definitely a good idea, but to handle with care.
URL: https://labs.ripe.net/Members/erik/ripe-ncc-and-duke-university-bgp-experiment