> In IPv6, the simpler solution is to allocate a /64 to groups of machines that 
> serve such a function.
> If you need to move the group, you can simply move the entire prefix.

If we change the prefix, then I have to contact and deal with the bureaucracy 
of external corporate entities. This is a significant cost that is completely 
prevented by using NAT. Also, given that the prefix is a network address, now 
we have to contact a separate department with a separate bureaucracy to get 
routing changes approved. Again, how is this easier without nat? 

> You can break p2p just as quickly without NAT using policy. NAT doesn't 
> provide policy, it just limits
> your ability to choose your own policy.

The goal is not to break p2p.  The goal is to use NAT for various reasons, and 
the fact that it breaks p2p is just a benefit. You keep pointing out that NAT 
should be eliminated so that p2p will work, to me, that is an good argument for 
the opposite. NAT, at least in a coroprate world, is never going away. There 
are two many good reasons for it to exist. For a ISP/CPE or University 
environment, I understand your argument, but not for a corporate network.

If there were a good NAT46 implementation on a cisco asa, juniper firewall, 
checkpoint and others, then most corporate networks could stay in ipv4 RFC1918 
private IP addresses, get PA ipv6 global routable address space from their 
providers, and setup global NAT pools and have access to ipv4 and ipv6 with no 
internal changes. It may not be ideologically pure, but it would work, as least 
as well as it does now, and allow the migration to ipv6 to move forward easier.


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