On Sat, 22 Dec 2007 12:53:52 -0800 "Christopher Morrow" <morrowc.lists@gmail.com> wrote:
On Dec 22, 2007 12:23 PM, Ross Vandegrift <ross@kallisti.us> wrote:
On Fri, Dec 21, 2007 at 01:33:15PM -0500, Deepak Jain wrote:
For example... Within one's own network (or subnet if you will) we can absorb all the concepts of V4 today and have lots of space available. For example... for the DMZ of a business... Why not give them 6 bits (/122?) are we anticipating topology differences UPSTREAM from the customers that can take advantage of subnet differences between /64 and /56 ?
I am confused on this point as well. IPv6 documents seem to assume that because auto-discovery on a LAN uses a /64, you always have to use a /64 global-scope subnet. I don't see any technical issues that require this though. ICMPv6 is capable of passing info on prefixes of any length - prefix length is a plain old 8bit field.
Uhm, so sure the spec might be able to do something different than /64 but most equipment I've used only does auto-conf if the prefix is a /64 :( Somewhere along the path to ipng we got reverted to classful addressing again :(
Not really. Classful IPv4 defined both an addressing structure *and* an agorithm to match destinations against the route table entries (i.e. classful forwarding won't match on a default route if the router knows at least one prefix within a classful network). IPv6 uses the longest match rule regardless of any addressing structure, and only uses structure for a few portions of the total IPv6 address space, for the operation of things like DHCPv6 and address autoconfiguration. A change in IPv6 addressing structure won't involve a change in the route table matching algorithm. Regards, Mark. -- "Sheep are slow and tasty, and therefore must remain constantly alert." - Bruce Schneier, "Beyond Fear"