Keith Moore writes:
don't think upgrade; think coexistence.
How do IPv4 and IPv6 coexist? Like ASCII and EBCDIC, perhaps?
As an engineer, the right thing to do is to transition away from NAT
(along with IPv4), so that eventually it can be discarded.
I'm not aware of a smooth transition option; how does it work?
And NAT is economically driven. Unless ISPs stop charging for extra
addresses, it's hear to stay.
for some applications, it's simply impractical; for other apps, it's
much more expensive (in terms of added infrastructure and support costs)
to operate them in the presence of NAT. in either case the market for
those apps is greatly reduced, and the apps are more expensive as a result.
It might still be cheaper than converting them to IPv6.
again, this doesn't really solve the problem - it only nibbles off a
small corner of it. NATs do harm in several different ways - they take
away a uniform address space, they block traffic in arbitrary
directions, they hamper appropriate specification of security policies,
and these days they often destroy transparency.
Agreed, but they reduce the amount of money you must pay to your ISP
each month by a factor of ten or more.
the reason this looks so complicated compared to NATs is that NATs never
really worked all of this stuff out. NATs started with a simple design,
pretended it would work well without doing the analysis, and have been
trying to fix it with bizarre hacks ever since that have only made the
People will go to great lengths sometimes to save money.
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