ANS begins filtering...
- To: apops at apnic dot net
- Subject: ANS begins filtering...
- From: "David R. Conrad" <davidc at apnic dot net>
- Date: Thu, 15 May 1997 13:38:56 +0900
- Sender: firstname.lastname@example.org
------- Forwarded Message Date: Thu, 15 May 1997 00:03:56 -0400 From: Curtis Villamizar <curtis at brookfield dot ans dot net> To: nanog at merit dot edu cc: curtis at ans dot net Subject: prefixes not registered in the IRR/GRR There have been a few recent incidents of incorrect routing information propagated by major providers that have caused substantial outages. An example, though by no means the only example, is the recent AS7007 announcements trig-erred by a routing software bug. In the AS7007 case, some providers had filters in place within 15-20 minutes while others never put filters in place and the upstream provider took over 2 1/2 hours to block the announcements at the source. We've seen similar slow response in other incidents. The AS7007 was easy to detect and isolate because very many destinations where impacted. Other incidents have occurred that impacted a lesser number of prefixes. This type of outage is very hard for a provider to detect. In order to insure that these routing anomalies can no longer impact connectivity within ANS, we will begin filtering routing information based on registered route objects in the IRR/GRR, that is the ANS, CANET, MCI, RIPE, and RADB databases. If you are unfamiliar with the IRR/GRR, documentation is available at: http://www.ra.net/RADB.tools.docs/.docs.html Brief instructions on registering objects are provided at: http://www.ra.net/RADB.tools.docs/register.html During April ANS took routing dumps, analyzed ANS routing policy, and identified 2,829 announced prefixes that were not registered and not covered by an aggregate (reachable anyway). During early April, emphasis was placed on verifying ANS routing policy files. From April 25 to April 29 notifications were sent to 312 origin AS, covering 2,108 of the unregistered prefixes. Notification could not be sent to 151 origin AS covering 721 prefixes due to lack of contact information for the origin AS. Quite a number of the origin AS contacted registered the missing prefixes. Others have not responded and of course those who were not contacted have not corrected problems. We'd like to thank the many people who promptly made corrections. The number of unregistered prefixes has been reduced by almost 1/3. There still remain 2,096 prefixes from 333 origin AS that are not registered. We've put together a web page describing the methodology and listing the remaining unregistered prefixes. The URL is: http://engr.ans.net/route-dumps/ It also interesting to note that 8,562 unregistered prefixes were excluded from these reports because they were overlapped by aggregates. The vast majority of these were /24 prefixes. This may indicate that 8,562 (or more) prefixes need not be included in global routing but are leaking from their aggregates. Curtis ------- End of Forwarded Message _________________________________________________________________________ To unsubscribe: send "unsubscribe" to apops-request at apnic dot net ------------------------------------------------------------------------