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

Jack Bates jbates at brightok.net
Thu Feb 5 15:13:09 UTC 2009

Matthew Moyle-Croft wrote:
> I'm under no allusion that a /64 is going to be optional - it's really 
> too late which is sad.  I think people have just latched onto it and now 
> accept it and defend it without thinking about "is this still the 
> answer?".   Just because it's in an RFC doesn't mean it's still the 
> right answer in a changing world.

My understanding is that there were long debates over if IPv6 would be 
64 bits or 128 bit. 64 bits of networks should hopefully get us out of 
my lifetime. IPv4 wasn't always classless, though, so the rules may 
change, but not before we absolutely need it.

> Yep - that's what I'm hoping (as I've said and clarified).   But I think 
> the reality is that in the provider world, no matter what people here 
> say, customer demand for an unchanging IPv6 range will increase not 
> decrease - driving up provider routing size and complexity.

We're assigning /60's via PD with network rotation, and will assign /56 
or /48 if it's justified as a static assignment (though possibly handed 
out via PD). The latter needing SWIPs according to ARIN.

A lot of people are trying to get their heads around IPv6, and the 
customers are really have problems with it. This isn't anything new. 
Tools and implementations will be built and improved to support the 
dynamic nature of IPv6 and make things easier for customers so that they 
don't have to worry about renumbers.

Proper CPE routers should be able to receive PD, assign their 
interfaces, and even issue PD to other routers in the network.


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