v6 & DSL / Cable modems [was: Private use of non-RFC1918 IP space (IPv6-MW)]

Seth Mattinen sethm at rollernet.us
Thu Feb 5 01:35:08 UTC 2009

Mark Andrews wrote:
> In message <498A3CA5.6060801 at internode.com.au>, Matthew Moyle-Croft writes:
>> Anthony Roberts wrote:
>>> On Thu, 05 Feb 2009 11:08:44 +1030, Matthew Moyle-Croft
>>> <mmc at internode.com.au> wrote:
>>>> Let's face it - the current v6 assignment rules are to solve a 1990s set 
>>>> of problems.  A /64 isn't needed now that we have DHCP(v6).
>>> It's needed to prevent people from NATing in v6, as they'll still want
>>> their stuff behind a firewall, and some of them will want subnets.
>> Why do we want to prevent people using NAT?   If people choose to use 
>> NAT, then I have no issue with that. 
>> This anti-NAT zealotism is tiring and misplaced. 
> 	NAT's break lots of things and increase the development
> 	costs of every piece of network based software being written.
> 	If we could get a true accounting of the extra cost imposed
> 	by NAT's I would say it would be in the trillions of dollars.
> 	NAT's are a necessary evil in IPv4.  If every node that
> 	currently communicates to something the other side of a NAT
> 	was to have a global address then we would have already run
> 	out of IPv4 addresses.
> 	NAT's are not a necessary evil in IPv6.  Just stop being
> 	scared to renumber.  Addresses are not forever and when you
> 	design for that renumbering get easier and easier.
> 	For everything else there are alternate solutions.

Far too many people see NAT as synonymous with a firewall so they think
if you take away their NAT you're taking away the security of a firewall.

A *lot* of these problems we face are conceptual rather than technological.


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