[arin-ppml] ARIN-prop-127: Shared Transition Space for IPv4 Address Extension

Jack Bates jbates at brightok.net
Thu Jan 20 11:36:50 EST 2011

Oppose prop 127

On 1/20/2011 10:26 AM, ARIN wrote:
> Updates 4.10 of the NRPM:
> A second contiguous /10 IPv4 block will be reserved to facilitate IPv4
> address extension. This block will not be allocated or assigned to any
> single organization, but is to be shared by Service Providers for
> internal use for IPv4 address extension deployments until connected
> networks fully support IPv6. Examples of such needs include: IPv4
> addresses between home gateways and NAT444 translators.

For the use proposed, /10 is not enough space. It is also a use which is 
not region specific, and wasteful for each region to specify their own 
space for such purposes.

> Until such customers replace their Home Gateways and all IPv4-only
> devices with IPv6-capable devices, Service Providers will be required to
> continue to offer IPv4 services through the use of an IPv4 address
> sharing technology such as NAT444. A recent study showed that there is
> no part of RFC1918 space which would not overlap with some IPv4
> gateways, and therefore to prevent address conflicts, new address space
> is needed.

Overlap with home gateway addressing is not a concern of ARIN. RFC1918 
could be utilized and home gateways reconfigured if necessary. It is 
wasteful to allow a small percentage of possible conflicts to warrant 
additional space. The larger conflict of RFC1918 space is cpe management 
addressing which used RFC1918, in which case, a very large cable company 
just ran out and had to request addressing to support this case. A /10 
wouldn't come close to supporting that many subscribers.


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