On Tue, 1 Jan 2008 12:57:17 +0100 Iljitsch van Beijnum <iljitsch@muada.com> wrote:
On 31 dec 2007, at 1:24, Mark Smith wrote:
Another idea would be to give each non-/48 customer the first /56 out of each /48.
Right, so you combine the downsides of both approaches.
It doesn't work when ARIN does it:
Well, ARIN aren't running the Internet route tables. If they were, I'd assume they'd force AS6453 to do the right thing and aggregate their address space.
* 24.122.32.0/20 4.68.1.166 0 0 3356 6453 11290 i * 24.122.48.0/20 4.68.1.166 0 0 3356 6453 11290 i * 24.122.64.0/20 4.68.1.166 0 0 3356 6453 11290 i * 24.122.80.0/20 4.68.1.166 0 0 3356 6453 11290 i * 24.122.96.0/20 4.68.1.166 0 0 3356 6453 11290 i * 24.122.112.0/20 4.68.1.166 0 0 3356 6453 11290 i * 24.122.128.0/20 4.68.1.166 0 0 3356 6453 11290 i * 24.122.144.0/20 4.68.1.166 0 0 3356 6453 11290 i * 24.122.160.0/20 4.68.1.166 0 0 3356 6453 11290 i * 24.122.176.0/20 4.68.1.166 0 0 3356 6453 11290 i * 24.122.192.0/19 4.68.1.166 0 0 3356 6453 11290 i * 24.122.224.0/20 4.68.1.166 0 0 3356 6453 11290 i * 24.122.240.0/20 4.68.1.166 0 0 3356 6453 11290 i
And it's unlikely to work here: for those standard size blocks, you really don't want any per-user config: you want those to be assigned automatically. But for the /48s you do need per-user config, if only that this user gets a /48. So these two block sizes can't realistically come from the same (sub-) range.
Maybe I'm not understanding this correctly. Are you saying that customers who have a /56 would get dynamic ones i.e. a different one each time they reconnect? If they've got a routed downstream topology, with multiple routers and subnets (because of course, they've got 256 of them), I don't think customers will be very happy about having to renumber top /56 bits if e.g. they have a DSL line sync drop out and get a different /56. Static assignments of /56 to customers make sense to me, and that's the assumption I've made when suggesting the addressing scheme I proposed. Once you go static with /56s, you may as well make it easy for both yourself and the customer to move to a /48 that encompasses the original /56 (or configure the whole /48 for them from the outset). Regards, Mark. -- "Sheep are slow and tasty, and therefore must remain constantly alert." - Bruce Schneier, "Beyond Fear"