North American Network Operators Group

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Re: Communities

  • From: Iljitsch van Beijnum
  • Date: Tue Oct 16 06:14:01 2001

On Tue, 16 Oct 2001, Niels Bakker wrote:

> > I've been thinking about other information that could be conveyed in
> > communities. For instance, bandwidth, delay and packet loss.

> And generate a route flap every time a link gets used more or less?
> That would be suboptimal to say the least (the word `countereffective'
> seems more applicable to me).

Using dynamic data for this is not going to work in BGP, so this would
have to be static information (hm, packet loss is not too static,
hopefully).

Static system-derived or configured information would already help a lot.
You can then easily select the route with the highest potential bandwidth
or the lowest speed-of-light delay, without the need to know a lot about
the internals of a transit network.

Introducing "metrics" like this like this is not contrary to BGP design
philosophy: the way in which an AS selects the best route is not defined
in the RFC and the length of the AS path is certainly not the best
possible criterion.

The processing along the way would be limited to a simple addition
(delay), compare/replace (bandwidth) or multiplication (packet loss)
without introducing anything SPF-like.

Iljitsch