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Re: IPv6 end user addressing
From: Alexander Harrowell <a.harrowell () gmail com>
Date: Wed, 10 Aug 2011 11:55:15 +0100

On Monday 08 Aug 2011 22:00:52 Owen DeLong wrote:

On Aug 8, 2011, at 7:12 AM, Mohacsi Janos wrote:



On Mon, 8 Aug 2011, Valdis.Kletnieks () vt edu wrote:

On Mon, 08 Aug 2011 10:15:17 +0200, Mohacsi Janos said:

- Home users - they usually don't know what is subnet. Setting up
different subnets in their SOHO router can be difficult. Usually 
the
simple 1 subnet for every device is enough for them. Separating 
some
devices into  a separate subnets is usually enough for the most
sophisticated home users. If  not then he can opt for business 
service....

You don't want to make the assumption that just because Joe Sixpack 
doesn't
know what a subnet is, that Joe Sixpack's CPE doesn't know either.

And remember that if it's 3 hops from one end of Joe Sixpack's 
internal net to
the other, you're gonna burn a few bits to support heirarchical 
routing so you
don't need a routing protocol. So if Joe's exterior-facing CPU gets 
handed a
/56 by the provider, and it hands each device it sees a /60 in case 
it's a
device that routes too, it can only support 14 devices.  And if one 
of the

more exactly 16 routing devices. You don't have to count the all 0 
and all 1 as reserved.... maybe each deeice can see /57 or /58 or 
/59.... depending of capabilities your devices....

I think daisy chaining of CPE routers is bad idea - as probably done 
in several IPv4 home networks. Why would you build several hierarchy 
into you network if it is unnecessary?


I can see things like wanting to have an entertainment systems network 
that is fronted
by a router with additional networks for each entertainment system 
fronted by their
own router, segmentation of various appliance networks with possibly 
an appliance
front-end router, etc.

There are lots of possibilities we haven't thought of here yet. 
Limiting end-users
to /56 or worse will only stifle the innovation that will help us 
identify the possibilities.
For this, if no other reason, (and I cite the limitations under which 
we have begun
to frame our assumptions about how the internet works as a result of 
NAT as an
example), I think we should avoid preserving this cultural 
conditioning in IPv6.


Owen




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. 


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


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.


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.
-- 
The only thing worse than e-mail disclaimers...is people who send e-mail 
to lists complaining about them

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