At 05:22 AM 4/20/2003 +0700, Robert Elz wrote:
But if you assume that there are people (and there most probably are) who
are so sold on the "benefits" of NAT, that they're going to use NAT no
matter how much you show them that there is in fact no benefit at all
(which for a site with an IPv6 global /48, and site locals, is certainly
true) then why would you care what address they're using behind the NAT?
That is, whether it is SL, LL, or some random "global" prefix they calculated
by tossing coins.
Actually, it isn't true that an IPv6 global /48 prefix plus site
locals would provide all of the "benefits" of NAT.
In particular, you would still need to renumber your local network
(the global prefixes) when your provider-allocated global
addresses change. Having extra addresses available for internal
traffic (the site-locals) does not make renumbering the global
prefix any easier or less expensive.
Although NAT causes various problems, it does offer a high degree
of provider-independence for internal nodes. You won't get this
using provider-allocated global addresses in IPv6, no matter how
many other addresses you add to each node.
Of course, this isn't why NAT is most often used... NAT is most
often used to extend a single address to cover multiple systems
in a home or small office environment. For that environment,
an IPv6 /48 (without site-locals) would suffice to replace NAT.
I find it almost inconceivable to believe that anyone is deciding the fate
of SL addressing by reference to NAT - that's simply too ludicrous (and sad)
I am similarly disturbed that there are people who want to
specify site-local addressing because they think it will offer
the provider-independence currently offered by NAT.