IPv6 end user addressing

Scott Helms khelms at ispalliance.net
Fri Aug 12 14:18:28 UTC 2011

On 8/11/2011 6:09 PM, Owen DeLong wrote:
> On Aug 11, 2011, at 2:53 PM, Scott Helms wrote:
>> On 8/11/2011 5:28 PM, Owen DeLong wrote:
>>> You're talking about the front end residential gateway that you manage. I'm talking about
>>> the various gateways and things you might not yet expect to provide gateways that residential
>>> end users will deploy on their own within their environments.
>> The question I asked you is why should I as the service provider deploy routers rather than bridges as CPE gear for residential customers.  If you didn't understand the question or didn't want to address that specific questions that's fine, but you certainly didn't answer that question.
> I think i did below. However, in my region of the world, most service providers don't provide the
> CPE and most customers are BYOB.

Are you not CONUS?  I thought I specified North American market, if not 
that was my intent, and in NA the service providers do supply in excess 
of 95% of all CPE.  (Keep in mind that the term CPE is actually a little 
dangerous since telcos use it one way and cable providers another, in 
this case I am referring to the access device that provides the PHY 
translation from the access network (DSL, DOCSIS, FTTx, wireless, etc) 
and that device, which can be a router or a bridge, is almost always 
provided by the service provider.)  My entire question is really should 
that device be a router in the future in your opinion.

>>> Of course, in order for the ISP to properly support these things in the home, the ISP
>>> needs to terminate some form of IPv6 on some form of CPE head-end router in the
>>> home to which he will (statically or otherwise) route the /48 whether it is statically
>>> assigned or configured via DHCPv6-PD.
>> What is a CPE head-end router?  That seems like an oxymoron.  Where would such an animal live, in the home or the head end/central office?  Who is responsible for purchasing it and managing it in your mind?
> In the home and the consumer is responsible. The fact that you utterly want to avoid
> the concept of topology in the home shows me that you really aren't understanding
> where things already are in many homes and where they are going in the future.
> ISP->CPE Head End Router-><Multiple additional routers and other deivces some of which have additional routers and or topology behind them.

I'm not avoiding anything, the term CPE head end router is oxymoronic 
and AFAIK isn't an industry term at all.  I simply want to understand 
where in the physical network this theoretical device lives and who owns 
it.  If its a customer premise device then you shouldn't describe it as 
having anything to do with the head end, since that's the other side 
(often a long way away) of the connection.

> Some definitions of the above pseudo-diagram already exist in many people's
> homes (and I am including Joe six-pack in this) today.
> Lots of users string wired and wireless routers together in multiple layers with and
> without NAT in various (and often creative albeit not necessarily constructive) ways
> within their homes.
> Today, all of that is hidden from you because their CPE head end router (the one
> that talks to your supplied bridge in most cases) NATs it all behind one address.
> In the future, it will be semi-visible in that you'll see the additional addresses, but,
> you still won't have to do anything about it because it's routed and all you have
> to do is deliver the /48 instead of delivering the /128 (equivalent of the /32 you
> deliver today).

Well, that's not really true.  Given the complexities of firewalls and 
allowed access the requirements for service providers to manage that for 
most home users is going to increase rather than stay the same or 
decrease.  That's kind of the point of TR-069 and the related suite 
(TR-098 especially).

Scott Helms
Vice President of Technology
ISP Alliance, Inc. DBA ZCorum
(678) 507-5000

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