On 2012-06-04 23:06, Owen DeLong wrote:
On Jun 4, 2012, at 6:11 PM, Jeroen Massar wrote:
On 2012-06-04 17:57, Owen DeLong wrote: [..]
If you're going to redesign the header, I'd be much more interested in having 32 bits for the destination ASN so that IDR can ignore IP prefixes altogether.
One can already do that: route your IPv6 over IPv4.... IPv4 has 32bit destination addresses remember? :)
It is also why it is fun if somebody uses a 32-bit ASN to route IPv4, as one is not making the problem smaller that way. ASNs are more used as identifiers to avoid routing loops than as actual routing parameters.
Greets, Jeroen
While this is true today (to some extent), it doesn't have to always be true.
If we provided a reliable scaleable mechanism to distribute and cache prefix->ASN mappings and could reliably populate a DEST-AS field in the packet header, stub networks would no longer need separate ASNs to multihome and IDR routing could be based solely on best path to the applicable DEST-AS and we wouldn't even need to carry prefixes beyond the local AS border.
The problem here does not lie with the fact that various of these systems (LISP comes to mind amongst others) have been well researched and implemented already, but with the fact that the general operator community will not change to such a new system as it is not what they are used to. Greets, Jeroen