On Mon, Mar 17, 2008 at 8:48 PM, Larry J. Blunk <ljb@merit.edu> wrote:
RFC2827 is about source address filtering which is not really the same as BGP route announcement filtering. Unfortunately, I have not come across
Yup, radb etc for that. Not fully awake when I wrote that, and hit send too soon. The PTCL thing was deliberate origination of a bogus prefix, meant for consumption by Pakistani ISPs . Abovenet too - they surely intended SOMETHING (no idea what) - announcements dont come tagged with communities (and communities with maybe 130 odd prefixes out of the huge number that abovenet advertises) simply by accident. Leaking that prefix out might be accidental - or it was not leaked at all, abovenet is massive, lots of transit customers. PTCL leaking youtube prefixes out to the world rather than pakistani ISPs was an accident. And their upstream PCCW not filtering weird and wonderful route advertisements from downstream customers was .. well, a decision that PCCW took (or rather, chose not to take) That wasnt the first bogus announcement PTCL made .. about a day or so after l'affaire youtube, I looked up PTCL's AS17557 on cidr-report, which also lists allocations announced and withdrawn in the past week. One interesting allocation .. 22.22.22.0/24 22.0.0.0/8 Prefixes added and withdrawn by this origin AS in the past 7 days. - 22.22.22.0/24 Withdrawn That's nic.mil IP space - and that sounds a lot like someone with enable at PTCL probably meant 202 or something similar, but is in the habit of typing new routes directly into production routers, rather than pasting it into a text editor and doing some syntax checking first, using cvs or svn for routes etc. There are enough calls for sBGP and such - but a lot can be accomplished before then simply by doing all the mom and apple pie best practice stuff (and by carrot-and-sticking other SPs into doing them, more importantly - especially any that fit the "large carrier upstream of multiple smaller ISPs with less than clued admins" type places. http://www.apnic.net/meetings/22/docs/tut-routing-pres-bgp-bcp.pdf for example. srs