On Mon, May 09, 2005 at 12:40:37PM +0200, Gert Doering wrote:
Personally, I opt for a /128+/64+/56+/48 model, with a suffiently relaxed policy that permits /48 assignments to anything that risks being limited by 256 subnets.
So typical large-scale DSL rollouts can be provisioned on an automated base with /56s, providing enough space for 99.99% of all customers ("pick another arbitrary number").
I do agree that /56s will be enough for almost all customers. But then you will see scenarious that people outgrow the /56 and need a new /48 and renumber AND restructure their network into this new space. THIS is what "/48 for everone" is trying to prevent as much as possible. Reserving a /48 space but only assigning /56 makes no sense either. A /56 is 256 subnets only if ignoring ANY hierarchy. If you accept 2-3 levels of hierachy into the customer network, your efficiency goes down, and 8bits of subnetting starts to smell v4ish again. I could probably agree to /56 for residential access though. But definately not for non-residential access like non-miniature companies, universities etc. Do we really gain enough by going down to /56 that is worth the hassle? IMHO, changing the HD-Ratio is a better idea, with no downside I can currently see (can anyone?). Best regards, Daniel -- CLUE-RIPE -- Jabber: dr@cluenet.de -- dr@IRCnet -- PGP: 0xA85C8AA0