[ppml] proposed updates to 2006-4

[Michael.Dillon at btradianz.com]

> 1. We should reserve a larger block than a /44.  Reserving larger 
> blocks at this point can likely only benefit us in the future as 
> networks grow.  I've proposed updating 2006-4 to a /40 reserved 
> block, but I'm open to discussing larger blocks if people think thatis 
needed.

Reservation of blocks was introduced for ISPs because
ISP networks are continually growing. This policy is intended
to apply to non-ISPs who do not experience the same scale
of network growth as ISPs. It should be able to assess an
applicant's overall needs and assign a single block that
will suit 99% of applicants for the foreseeable future.

Rather than reserving space, we need to have a sensible
assessment of the applicant's address needs, both now
and in the foreseeable future. 

--Michael Dillon