Hi, I'm looking at a number of transit providers in Europe who offer communities that will limit the scope of an announcement by geographic region. For example if you are AS1 you can tell upstream AS2 to propagate your announcements only to peers and neighbors within EU, but not those in the NA or AP regions. This helps networks with unique routing policies. (If you're curious what these might be, just ping me offlist) I'm looking for feedback from people who have done this before. All advice, experiences (preferably with what upstream ASNs) is helpful. Our concerns are basically that this puts a management and engineering aspect of our network into someone else's hands to not mess up. I already know we deal with peers who leak routes, but my guess is that since this is a business relationship with the upstream network they are less likely to bork it up and hopefully manage it programatically. Wishful thinking or sound practice/service offered by high-quality carriers? My questions are thus: 1) I'd this to find out how reliable it is/was (were your routes ever leaked)? 2) How effective it is/was (did it accomplish your goals)? 3) Advice you might have for someone who is considering doing this? Providers to shy away from? Providers who are pretty good? Thanks, David Ulevitch