[address-policy-wg] IXP pool lower boundary of assignments

* Matthias Wichtlhuber

> I don't get the point of the /29 discussion anyways. It is based on
> the false assumption that we need to stretch the pool to eternity and
> beyond. We need to stretch the pool until we can test and establish
> IPv4 over IPv6 peering LANs. A /26 default is perfectly fine for
> that.

While I do hope you will be proven to be right about that, I am not so
optimistic. The industry's track record on being able to migrate away
from IPv4 to IPv6 before the exhaustion of the former is not great, to
put it mildly.

That even goes for the IXP pool specifically:

In 2011, we thought a /16 with a default assignment size of /24 would
suffice to «safeguarding future IXPs with IPv4 space».

In 2019, we realised that was too optimistic, doubling the pool size to
a /15, keeping the default /24.

In 2022, we are again realising that we were too optimistic, leaving
the pool size unchanged (for obvious reasons), but aiming to reduce the
default size to /26.

Perhaps third time's the charm. I do hope so, really, but again - not
optimistic. George Santayana's observation comes to mind: «those who
cannot remember the past are condemned to repeat it».

Tore