Addressing plan exercise for our IPv6 course

Fri Jul 23 11:07:01 CDT 2010

It is not about how many devices, it is about how many subnets, because you
may want to keep them isolated, for many reasons.

It is not just about devices consuming lots of bandwidth, it is also about
many small sensors, actuators and so.

The ISP "new" business is not just about more bandwidth but also about
offering new services, which they can charge for. Those services are very
difficult to deploy in NATed scenarios such as the one that we have today
with IPv4.

And I'm not saying to forget about what we have learn with DHCP, in fact
DHCPv6 has many new and good features, but for many reasons,
autonconfiguration is good enough, and much more simple.


> From: Matthew Kaufman <matthew at>
> Reply-To: <matthew at>
> Date: Fri, 23 Jul 2010 07:22:53 -0700
> To: Jordi Palet Martínez <jordi.palet at>
> Cc: <nanog at>
> Subject: Re: Addressing plan exercise for our IPv6 course
>> And then next you can say ok, so /32 bits is big enough for your home, so
>> let's change it again, kill autoconfiguration, ask existing IPv6 users to
>> redo their addressing plans, renumber, etc., and use all the rest of the
>> bits for routing ?
> I *really* don't understand why a /32 isn't big enough for a home. Even
> if you insist on SAA for getting the addresses. How many IPv6 devices is
> the guy going to plug in / attach wirelessly anyway?
>> And so on, of course, where is the limit ? You should propose this to 6man
>> at the IETF.
> The same IETF that until just a few months ago believed that DCCP and
> SCTP would be wildly successful as new IP protocols because NATs don't
> matter?
>> You're not getting it. Autoconfiguration is a very good feature.
> No, no it isn't. It goes on the list of "interesting ideas for IPv6 that
> were good enough to be implemented, and refined (in this case as DHCP),
> for IPv4". Insisting on SAA is basically saying "well, you know all
> those things we learned when we deployed DHCP... lets go ahead and
> forget them and pretend that home machine OS vendors *and* IT
> departments are wrong.
>> More bits
>> for the user to subnet means more business for smart ISPs who don't want to
>> sell addresses but instead services and applications much more easier to
>> deploy thanks to a uniform /48 ways to address all end sites.
> I fail to see how a household, even a really big one, is going to attach
> more bandwidth-consuming devices (which I presume is how the ISP does
> more business) to a link with a /48 on it vs a link with a /64 on it. A
> /64 allows more machines in your house than today's entire Internet has
> connected. Unless you have a new plan for electric power delivery to the
> home, there's no need to go beyond that.
> Matthew Kaufman

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