On Wed, Dec 28, 2011 at 6:23 AM, Iljitsch van Beijnum <[email protected]> wrote: > Also somehow the rule that all normal address space must use 64-bit interface > identifiers found its way into the specs for no reason that I have ever been > able > to uncover. On the other hand there's also the rule that IPv6 is classless and > therefore routing on any prefix length must be supported, although for some > implementations forwarding based on > /64 is > somewhat less efficient.
This ambiguity has always bothered me. The address architecture RFC requires a 64-bit interface identifier, but it's required to be unenforced by implementation, which makes it more of a suggestion at best. I think the wording should be updated to changed MUST to SHOULD. That said, and despite my own use of prefix lengths other than 64-bit, I do believe that a 64-bit prefix for each host network is in our long-term interest. Not having to size networks based on the number of hosts is a good thing. Features made possible by a 64-bit address space is a good thing. -- Ray Soucy Epic Communications Specialist Phone: +1 (207) 561-3526 Networkmaine, a Unit of the University of Maine System http://www.networkmaine.net/
