IPv6 end user addressing

Wed Aug 10 13:02:19 UTC 2011

> 
> Thinking about the CPE thread, isn't this a case for bridging as a 
> feature in end-user devices? If Joe's media-centre box etc would bridge 
> its downstream ports to the upstream port, the devices on them could 
> just get an address, whether by DHCPv6 from the CPE router's delegation 
> or by SLAAC, and then register in local DNS or more likely do multicast-
> DNS so they could find each other. 
> 
Why do I want my kid's network seeing all the multicast packets that are
streaming the adult video from the player to the TV and the Amp in the
master bedroom?

Why do I want my appliance network's multicast packets getting tossed
around on the guest wireless?

Bridging eliminates the multicast isolation that you get from routing.

This is not a case for bridging, it's a case for making it possible to do real
routing in the home and we now have the space and the technology to
actually do it in a meaningful and sufficiently automatic way as to be
applicable to Joe 6-Mac.

> 
> And then it really doesn't matter; everything gets its address, nothing 
> is NATted, every address is mapped to a meaningful hostname.
> 

This assumption that an entire household should be a single broadcast
(or multicast) domain is fundamentally broken and needs to change
going forward.

> 
> Perhaps you'd need more aggregation and routing in the glorious one-IP-
> per-nanite-and-Facebook-fridges future, but that's for another day once 
> we've got fusion and a rational system of government out of the way:-) 
> Joe's network as described isn't big enough or clever enough to need 
> multiple routers. It's just a small LAN and it's only Joe's weirdness in 
> using a $500 Roku as a $5 hank of cat5e and a $20 4-port switch that 
> prevents it from being so.
> 

I think that the nanites and fridges that talk to other kitchen storage
systems will actually happen well before fusion or rational government.

Just because what you describe of today's situation is an accurate
picture of today does not mean it is how we should plan IPv6. Remember,
we don't want to have to replan IPv6 or switch to yet another numbering
system for several years, if not decades. In case you hadn't noticed, doing
so at today's scale is hard. Imagine what it will be like next time.

> 
> Not all problems should be solved by routing - but a list full of 
> "router people" is inherently likely to try to solve all its problems 
> with more routers and routing.

There are reasons to route and reasons to switch. I don't consider myself
a router person, but, I do consider myself a network engineer, so, I try
to use the right tool for the right job. In the case of LAN isolation which
I can see several desirable applications for in a home, I think routing
is a better choice than switching.

Remember, the multicast scopes in IPv6 are interface, link, and larger.
There's no scope in between everything on this interface and everything
on this link. (link == layer 3 network).

Owen