On Mon, 31 Dec 2007 13:18:41 -0800 Joel Jaeggli <joelja@bogus.com> wrote:
Mark Smith wrote:
Another idea would be to give each non-/48 customer the first /56 out of each /48. If you started out with a /30 or /31 RIR block , by the time you run out of /48s, you can either start using up the subsequent /56s out of the first /48, as it's likely that the first /56 customer out of the /48 would have needed the /48 by that time.
As stated, that approach has really negative implications for the number of routes you carry in your IGP.
Well, for 120K+ customers, I doubt you're using an IGP for anything much more than BGP loopbacks - and you'd have to be aggregating routes at a higher layer in your routing hierarchy anyway, to cope with 120K routes, regardless of what method you use to dole out /48s or /56s to end-sites.
Alternatively you might have become more comfortable with giving each customer a /48, and wouldn't require any of them to renumber - they'd just have to shorten their prefix length.
Regards, Mark.
-- "Sheep are slow and tasty, and therefore must remain constantly alert." - Bruce Schneier, "Beyond Fear"