16-bit ASN kludge

Sun Dec 5 14:55:04 UTC 2004

On 4-dec-04, at 21:04, Edward B. Dreger wrote:

> I suppose there could be in excess of 65431 transit networks.  I think
> that's why Owen suggested reserving, say, 2^20 ASNs for transit in
> 32-bit space.

How does this make sense? If you have one of the ASes in the range 2^16 
- 2^20-1 you, your customers and your transits still need to be able to 
handle 32 bit AS numbers. Apart from the backward compatibility being 
slightly more important for transit networks there is no upside to 
having a separate transit network and leaf network AS space.

> IvB> What would you like to optimize for?

> Application of Dijkstra's algorithm.

Well, then you're in luck as BGP is highly optimized in this regard: it 
doesn't use the Dijkstra or SPF algorithm. BGP is pretty much a 
distance vector routing protocol.