IPv6 Confusion

Nathan Ward nanog at daork.net
Wed Feb 18 03:16:47 UTC 2009

On 18/02/2009, at 3:04 PM, Steven Lisson wrote:

> ISP gets a chunk of IPv6 address space, sets up customers with it,  
> gets
> their big lovely carrier grade NAT device that NAT's from customers  
> IPv6
> address to whatever IPv4 service they need.
> I'm probably missing something but does this not seem like a good
> option? Why not use IPv6 instead of private IPv4, end user gets
> end-to-end connectivity with anything that is IPv6 enabled while still
> being able to access the legacy IPv4 network.

Or, you do dual-stack, so their applications do not have to be  
modified to support IPv6 - they only need to support IPv4 (with NAT)  
like they always have. They have IPv6 to do end-to-end, and IPv4 to do  
client-to-server, or for legacy application support.

How many of your customers are likely to be running Windows XP in 2  
years? Probably still quite a few - they will not be able to function  
on IPv6-only, as they do not have DHCPv6. In the current state of  
things, IPv4 to the edge is going to be required for some time still I  

Sure, over time applications will need IPv6 support. That is not going  
to be likely to be done by the time we run out of IPv4 resources for  
the edge.

Nathan Ward

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