[ppml] [address-policy-wg] Those pesky ULAs again

[Paul_Vixie at isc.org]

> - IPv6 space is not infinite.  It's a 64-72 bit address space.  That's
>   right, subnets with > 256 hosts are very uncommon today, so we've wasted
>   64 bits to number 256 things.  That makes the space effectively on the
>   long end 72 bits.

according to <http://www.ipv6conference.com/conference.htm>, i gave a talk
entitled "DHCPv6 - The Case Against Stateless Autoconfig" at NAV6TF'2005.

according to <http://www.isc.org/index.pl?/sw/dhcp/dhcp4_0.php>, there's
now code in "alpha test release" status to handle DHCPv6.

imho, the days of EUI64 are numbered.  at home i'll probably use a /120 for
each LAN.  at work, we might splurge and use /96's.  not that a /56 isn't
enough for my house or anything, i just want the sparseful wastitude of the
new address bits in IPV6 to all be at the top end.  i'm using a /124 for my
T1, mostly to make the PTR's easy to write and read.

>   But more importantly, we have the T-Shirt from this exercise.
>   Back in the 80's we gave out Class A's.  It was the right thing
>   to do.

was it?  DEC got 16.0.0.0/8 on the basis of having 130000 employees and
something like 10000 offices.  they turned in five class B's to get the A.
does anybody here think that DEC needed a class A by ARIN's current 
standards?  this was a post-subnet, post-CIDR allocation.

>   I predict with the current allocation procedures IPv6 will be
>   "used up" in my lifetime.  I also predict the groups today getting
>   /32's (and larger) will look like the legacy class A holders in
>   20 years time.  When your doorknob automatically requests a ULA-C
>   /64 when you bring it home, and your house has 2,000 of them as every
>   individual system talks to each other we'll be looking at this quite
>   differently.

i include this only so that i can say, i nearly agree.  unless we have an
IP architecture that splits EID/RID, those doorknobs will not be globally
reachable.  (not that this is a problem for doorknobs but it might be for
microwave ovens or something.)