Re: Cogent/Level 3 depeering

[Joe Abley <jabley () isc org>]

On 5-Oct-2005, at 15:22, Jeff Shultz wrote:

> Interesting. Balkanization of the Internet anyone? As one other  
> commenter hinted at, it does sound like a recipe for encouraging  
> multi-homing, even at the lowest levels. How many ASN's can the  
> system handle currently?

It's a 16-bit number; 0 isn't used, and the IANA (per RFC 1930)  
reserves 64512 through 65535 for private use. So from a resource  
allocation perspective, the answer is 64511.

There is a proposal to introduce 32-bit AS numbers. See, for example:

  http://www.ietf.org/internet-drafts/draft-ietf-idr-as4bytes-11.txt
  http://www.ietf.org/internet-drafts/draft-huston-idr-as4bytes- 
survey-00.txt

We have talks scheduled for Los Angeles about AS number exhaustion.


Joe