Michael has very good points here: It would be a lot better to have globally unique addresses rather than re-usable SLs. But how do we do that? Well, if we could allocate a /3 and make:
001x:xxxx:yyyy:SLA:E:U:I:64 = my address 010x:xxxx:yyyy:SLA:E:U:I:64 = corresponding private, 010::/3 blackholed by policy. That would be nice, and I'd drop SLs in a heartbeat, but how realistic is that? Michel. > Michael Thomas wrote: > To my mind, one of the key failure modes of > overlay addressing is collisions when the original > assumptions of the overlay cease to be true -- > like when you get two companies who merge, say, > and their net 10 address spaces collide. This > drives integration attempts to a great deal of > distraction and a Quick Fix NAT(tm) is almost > certainly the result. > What you'd really like in that situation is to > renumber, but color me skeptical that renumbering > will ever be "easy" or "automatic", especially > when you consider the widespread conflation of > addresses as routing tags and as identity. Thus, > I think site locals will still beg the Quick > Fix NAT(tm). Badness. > If we instead say that you should just blackhole > otherwise globally routed prefixes at the site > boundary, we don't run into this problem. If you > have a change of policy, you just change some or > all of the prefix that gets blackholed instead of > renumbering. Just as easy, if not easier than > setting up NAT's, IMHO. -------------------------------------------------------------------- IETF IPng Working Group Mailing List IPng Home Page: http://playground.sun.com/ipng FTP archive: ftp://playground.sun.com/pub/ipng Direct all administrative requests to [EMAIL PROTECTED] --------------------------------------------------------------------
