Well the message I got earlier was the IPv6 will not fix
the NAT problem - true or not true?
depends on how you define "the NAT problem"
- if you define it as a shortage of addresses, then IPv6 *does*
solve the NAT problem - provided, of course, that the RIRs
are willing to assign reasonable sized blocks (much larger
than IPv4 assignments) and similarly, that ISPs do not charge
onerous amounts to route reasonably sized address blocks to
customers.
- if you define it as the ability to "plug and ping" small networks
into the Internet, then (as far as I can tell) we still need
a small piece of protocol beyond IPv6 to have a "pure IPv6"
plug-and-ping solution. in the interim, either PPP or DHCP
will give you an IPv4 address; this combined with 6to4
gives you a /64 on a plug-and-ping basis, and the protocol work
for this is already done.
- if you define the NAT problem as the ability to easily renumber
networks (or more precisely, the ability to avoid needing to
renumber networks), then IPv6 probably still needs a bit of work
until renumbering an IPv6 network is as painless an operation
as "renumbering" an IPv4 network using a NAT. of course the
NAT produces its own kind of pain, which you might or might not
realize is part of the cost of using a NAT to renumber.
- if you define the NAT problem as the ability to provide the
security and illusion of security that folks get from NATs,
rest assured that the same degree of security and illusion
can be provided using IPv6 mechanisms. However, with IPv6,
the NATs won't prevent applications that need stable addresses
from having them.
- if you define the NAT problem as the inability to run
certain kinds of applications, then yes, IPv6 does solve
those problems. however you have to modify your application
to run IPv6.
- if you define the NAT problem as the difficulty associated
with trying to bilaterally connect together various IPv4 networks,
each of which uses potentially overlapping address spaces, then yes
IPv6 solves this problem. (IPv6 seems like a big win for B2B
communications)
so to answer your question succinctly I'd say "mostly true".
I assume with IPv6 there is no need for NATs. Who thinks
they will still be around - humm maybe if the ISP charge
a fortune for 4 IP addresses vs 1 IP address (IPv6 or IPv4).
it's probably misleading to think of IPv6 vs. NATs as an either-or
situation. NATs will definitely be around for awhile - to provide
connectivity for legacy v4-based applications and networks,
(email and web will be primarily v4-based for a long time)
and NAT-PT to provide some measure of interoperability between
v6 and v4 apps. However, one hopes that NATs will not interfere
with pure v6 connectivity, so that applications that are written
for IPv6 will be able to rely on the increased functionality.
Keith