To what extent does setting communities on BGP routes work in the real
world?
I can't help suspecting that in reality, routes would get aggregated,
or communities would be dropped or replaced, somewhere between source
and destination.
Adam,
To what extent does setting communities on BGP routes work in the real
world?I can't help suspecting that in reality, routes would get aggregated,
or communities would be dropped or replaced, somewhere between source
and destination.
In order to prepare an IETF draft on the utilization of
extended communities to control the redistribution of routes
(see http://www.infonet.fundp.ac.be/doc/reports/draft-bonaventure-bgp-redistribution-02.txt)
we did a study of the utilization of the community attribute
for traffic engineering purposes. This study was based on two
sources of information :
- the RIPE whois database for the advertised communities
- the BGP routing tables collected by RIPE and routeviews
This analysis shows that BGP communities are becoming frequently
used for traffic engineering purposes. A summary of our findings
is available as
http://www.infonet.fundp.ac.be/doc/tr/Infonet-TR-2002-02.html
and you can find the analysed data on the web as well, see
http://alpha.infonet.fundp.ac.be/anabgp/
Our intention is submit this analysis as an informational RFC one
day to document the common utilizations of the community attribute
in today's Internet. Comments on the above mentionned report
are welcome.
Best regards,
Olivier Bonaventure