[arin-ppml] [Fwd: Draft Policy 2011-5: Shared Transition Space for IPv4 Address Extension]

The following statement from 2011-5 is incorrect or at a minimum chooses
to deliberately rule out one option.

> Service providers are currently presented with three options for
> obtaining sufficient IPv4 address space for NAT444/IPv4 extension
> deployments: (1) Request allocations under the NRPM; (2) share address
> space with other providers (this proposal); or (3) use address space
> allocated to another entity (i.e. ‘squat’).  Of the three options,
> option 2 (this proposal) is preferable, as it will minimize the number
> of addresses used for IPv4 extension deployments while preserving the
> authority of IANA and RIRs.

Which is use RFC 1918 space. The fact that there are conflicts with
addresses used in gateways in no way invalidates the suitability of
private scope ip addresses for use in a private scope. Creating new
private scope ranges which gateways do not treat as such has it's own
liabilities and at a minimum that needs to be acknowledged and balanced
against threat of collisions.