[ppml] The myth of IPv6-IPv4 interoperation, was: Re: Legacy /24s

[michael.dillon at bt.com]

> The point is that the transition to another address length 
> inherently means that hosts only implementing the shorter 
> length can't talk to ones only implementing the larger length 
> if those actually get to use that length as opposed to the 
> old length and a bunch of 0 bits.

Hmmm... Hosts implementing globally unique IPv4 addresses can't talk to
ones only implementing non-unique addresses.

True on the surface of it, but in practice people use NAT proxies and a
significant percentage of Internet traffic is between such incompatible
IPv4 hosts. 

Given that IPv4-IPv6 proxying is as simple to implement as PNAT, one
wonders why people are making such a fuss.

--Michael Dillon