Merit Network
Can't find what you're looking for? Search the Mail Archives.
  About Merit   Services   Network   Resources & Support   Network Research   News   Events   Home

Discussion Communities: Merit Network Email List Archives

North American Network Operators Group

Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical

Re: BGP4 COMMUNITY attribute

  • From: John W. Stewart III
  • Date: Thu Mar 27 14:34:58 1997

 > What is the general concensus about passing communities in the "community"?

i could see a reason for a subscriber passing communities
through a mid-level provider to a top-level provider.  but i'm
not sure if it makes sense [yet] for top-levels to pass
communities between themselves

 > > > 1. Is COMMUNITY a transitive attribute only between me and my immediate
 > > > upstream supplier or 
 > > > is it being propagated further into Internet (so I can influence how
 > > > somebody ,say, 5 AS hops 
 > > > away from me sees my routes) ?
 > >
 > >the attribute is defined as transitive (i.e., once associated
 > >with a route it *stays* associated with the route).  however, in
 > Unless an intermediate provider deliberately changes the value, as
 > opposed to appending to it.

these values aren't an end-to-end thing .. it's simply a
way for providers to more easily facilitate routing policies.
your comment implies somebody being a bad guy...

 > >practice, many providers are configured to not send communities
 > >to other providers
 > Is this a conscious decision or just that they have not turned on 
 > "send-community"?

both.  they don't turn on send-community so that others don't
see their communities.  maybe they have some whiz-bang features
that make configing their neat really cool, and they don't want
others to see their communities because it might imply a way for
others to do the same thing without the same amount of work

- - - - - - - - - - - - - - - - -

Discussion Communities

About Merit | Services | Network | Resources & Support | Network Research
News | Events | Contact | Site Map | Merit Network Home

Merit Network, Inc.