[address-policy-wg] PI concept in general, was IPv6 PI resource question!

On Wed, Feb 16, 2011 at 12:33 PM, Nick Hilliard <nick at inex.ie> wrote:
> Regarding routing slots, here's some hand-waving / back-of-a-napkin / finger
> in the air analysis:
[...]
> If there is massive ipv6 deaggregation, it will cause 4x the damage of the
> equivalent ipv4 deaggregation.  This is bad, and it will cost lots of people
> lots of money.
>
> Nick

Yeah, and this is exactly why I believe keeping stuff simple (eg,
approximately 10^3.14 times better with a PIv6 for a AS-cust who wants
to announce a route than cracking away at the "PA" LIR-blocks),
enables networks to filter deaggs in a much less destructive way.
Which brings us into LIR/BGP territory: IMNSHO policies should /
should continue to advice operators that "PA" space is
provider-dependent whereas PI is PI, in terms of non-guaranteed but
best-effort-expected routing goes. ;)

There is a much better chance to get it right with v6 due to its size
than v4, since we can be pretty specific about where PI and micro
allocs come from and where /32s-or-shorter come from, and they're not
overlapped.

While address assignment policies traditionally does not dictate
routing policies (it actually does set the lower bar in v6, plus
there's the multihoming bit :) ), it is better to lay the framework
for a constructive v6-land then a destructive one.

Also, costs, policies and administrativia should incentivize networks
to not check out a discontinuous PIv6 /48 per site if they have many.
Obviously, it is beneficial that networks operate out of contiguous
space rather than fragmented, since it allows routing policies to
automatically drop more-specifics.
Whether or not someone decides to do so is up to them, of course.  The
key is of course that the addressing allows it to happen.   This is
how I mean address assignment policies perhaps not dictate routing
policies, but they certainly lays the framework for how it can
operate.

Cheers,
Martin