Assigning IPv6 /48's to CPE's?

michael.dillon at bt.com michael.dillon at bt.com
Tue Jan 8 10:27:58 UTC 2008



> > The answer so far is that EVERYBODY gets a /48, but if you 
> think that 
> > there is a risk that you won't be able to get additional 
> /32s when you 
> > outgrow your first allocation, then give a /56 to RESIDENTIAL SITES.
> > This is not the same as dialup, i.e. residential sites could be 
> > connected with DSL, T1s, wireless, or whatever. In fact, if 
> a business 
> > is connected via dialup, you should give them a /48, because 
> > businesses have a habit of continuous growth, unlike 
> residences which 
> > tend to top out at 5 or 6 residents.
> >   
> We will probably disagree about this one. I will probably 
> give out /48 to residential broadband when we expand IPv6 to 
> residential. But dialup users typically have zero networks; 
> not even the single LAN of res broadband. 

I'm not talking about old folks hanging on to their 386 running
Windows 3.1. There is a vast expanse of real estate known as
rural America that is unlikely to get broadband anytime soon
due to the large distance from the exchange. But these residential
sites are often also family businesses with a network in the barn,
one in the feed silo, etc., etc. They deserve to be assigned an
IPv6 allocation under the same terms as urban sites, i.e. a /48.

Admittedly there are issues in getting IPv6 access to these folks
but in a world in which there aren't enough free IPv4 addresses,
it is still doable using an IPv4 island containing their modem
gateway, your terminal server and your IPv6 tunnel broker. Because
it's an IPv4 island you can hijack any old IPv4 addresses and nobody
will notice. And using IPv4 for transport avoids the need to upgrade
PPP and terminal servers to support IPv6. Those old IPv4 terminal
servers aren't likely to wear out anytime soon.

> Not that changing "all" of our IPv6 dialup users would take 
> more than a couple of calls :). Talk about a narrow niche.

For a rural ISP, it might be the core of their business.

One size does not fit all. There is still room for good old-fashioned
hackery in making an IPv6 Internet functional, just like the early
days of the commercial Internet when people were building terminal
servers out of Linux boxes, and hacking things like PoP before SMTP
to glue things together.

--Michael Dillon



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