Re: [Idr] new ID on expansion of private use ASN range

[Jeffrey Haas <[e-mail]>]

On Tue, Jul 03, 2012 at 09:39:48AM -0400, Jon Mitchell wrote:
> > If you want ~1M, pick 2^20 addresses.  You could probably even just do 2^16
> > and have most providers happy.  (2^16 was the number I had in mind for my
> > draft.)  This lets you align the private AS number at a convenient as.dot
> > boundary.  I could even forsee someone's CLI saying PRIVATE.<num> :-)
> 
> [JM]  Although 65K private ASNs meet our near term needs, BGP is being
> used further and further down in the DC, with proposals that push it
> even to the host/hyper-visor.  Therefore, given the large amount of
> space available, I think it makes sense to not limit this so artifically
> and be frustrating operators again 5-10 years from now as more and more
> creative network designs are proposed.  As for any implementation hoping
> to make more asdot friendly implementations and encourage it's use, I
> think this sounds like a good reason not to make the range 16 bits!

Mostly, if you're going to pick a range of addresses, just keep clean bit
alignment.  That would mean it's cleanly maskable in the code.

If you pick 2^20, you can have PRIVATE1.<as> through PRIVATE16.<as>.   While
I'm only partially serious about something like this as a UI mechanism, one
consideration is that 4-byte numbers in decimal format are big enough to be
difficult for humans to parse for convenience and having such mneumonics
might be very helpful.  (To be contrary, canonical display and machine
readable should always be as-plain formatted.)

-- Jeff