North American Network Operators Group|
Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical
Re: honoring AS-path prepend from a peer or customer?
On Thu, Feb 18, 1999 at 08:53:09PM -0500, Avi Freedman wrote: > Standard practice is to accept them, though you may need to tell > the peer or upstream what regexps to allow if they filter by as-path > as well as by prefix. (Always a good idea...) Yes, whenever I've set up customer/peer bgp sessions, I've done it such that we only did prefix filtering, not any as-path filtering, this allows them to prepend as they wish, just not advert anything other than what we filtered them at. > My side question is - what shipping routers will let you rewrite > AS-Paths by doing anything other than just prepending? Just wondering > if any 7007-type horrors are lurking in the wings. I believe Criscos, > Bays, and gated boxes can't do this (without BGP->IGP->BGP redistribution). I'm also interested. There have been vendor bugs that have tipped off 7007, etc.. but I'm only really familar with one vendor that (might) be able to do something like this. I would suspect that anyone not honoring your as-path prepending would be doing as-path filtering. - Jared -- Jared Mauch | pgp key available via finger from firstname.lastname@example.org clue++; | http://puck.nether.net/~jared/ My statements are only mine.