North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Communities BCP [was: RE: BGP Path Filtering]
> I like using BGP communities: > o filter announcements you receive from downstreams based on your > criteria of choice > o set a specific BGP community (yourAS:whatever) on > announcements which > are to be propagated to various places (upstream providers, etc.) > o do output filtering based on the communities you set > Make sure you clear yourAS:whatever in announcements from your BGP peers. > > You can use this same technique for prefixes you originate, so > that all your > outbound BGP filtering is based on communities. I am hijacking this thread a bit. Setting communities is excellent advice especially if you are just starting out with downstream ASes. The question is that changing your communities down the road might be a big headache depending on whether you'll come to need more advanced ways of filtering your announcements than coarse communities allow. Especially when going (through growth or acquisition) from a single metro network to a multi-metro or national/international one. What criteria does the community think should be used when specifying communities. IMO, overspecificity [sp?] doesn't hurt, but others may (and have) disagreed. What's the BCP? Thanks, Deepak Jain AINET
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