16-bit ASN kludge

Mon Dec 6 01:45:47 UTC 2004

--On Sunday, December 5, 2004 3:55 PM +0100 Iljitsch van Beijnum 
<iljitsch at muada.com> wrote:

>
> 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.
>
My thinking was that transit networks could aggregate leaf advertisements
and share only the aggregates instead of the more specifics.  The hope
here was that by having separate leaf/transit ASNs, we could perform another
level of routing table size management/optimization.

I think optimizing for backward compatibility for transit initially, and,
eventually, for transit routing table size while still providing leaf
multihoming capabilities is desirable.

Owen

-- 
If it wasn't crypto-signed, it probably didn't come from me.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 186 bytes
Desc: not available
URL: <http://mailman.nanog.org/pipermail/nanog/attachments/20041205/f17bc522/attachment.sig>