bicknell's blog

Origin ASN for Anycasted Services

26 Sep 2011
Leo Bicknell

 There is a new draft from the IETF GROW working group that attempts to standardize how Anycasted services manage their routing announcements.  The draft can be found at:

ftp://ftp.rfc-editor.org/in-notes/internet-drafts/draft-ietf-grow-unique-origin-as-01.txt

Before commenting directly on the draft a review of how ISC operates the F-Root Anycast network is in order.

F-Root Routing: How does it work?

24 Aug 2010
Leo Bicknell

ISC uses an unusual routing configuration for the F-Root name server. While the configuration is relatively easy to understand, it's hard to deduce by looking at the routing tables. We'll explain it here!

The network 192.5.4.0/23 is used for F-Root. The reasons for using this block are historical and unimportant, but the fact that it is a /23 is very important. Looking in the global routing table, you'll find 192.5.4.0/23 routed worldwide; ISC has obtained multiple transit providers for this network to provide excellent access to F-Root.

ASN Collisions and Human Error

03 Jan 2010
Leo Bicknell

There is nothing more sensational than the unexpected, and when the NANOG (North American Network Operators Group) community was recently informed that an ASN collision had occurred it caused a lot of people to sit up and take notice. This event was also very interesting in that researching takes us back to a time before ARIN and RIPE existed, creating an interesting historical twist.