[arin-ppml] End non-public IPv4 assignments?

Jimmy Hess mysidia at gmail.com
Wed Jan 26 20:41:14 EST 2011

On Tue, Jan 25, 2011 at 11:20 PM, Owen DeLong <owen at delong.com> wrote:

The NRPM 4.3.5  is already a policy whose effect is to restrict
assignments to non-connected networks. They are currently allowed when
they decide "private IP numbers are ineffective".
So a modified 4.3.5 could merely state

"4.3.5. Non-connected Networks
End-users not currently connected to an ISP and/or not planning to be
connected to the Internet are encouraged to use private IP address
numbers reserved for non-connected networks (see RFC 1918). When
private, non-connected networks require interconnectivity and global
IP address numbers are necessary, globally unique addresses may be
requested or received by application to ARIN or specified transfer and
used to provide this interconnectivity;  new allocations for
non-connected networks will be allocated from a block reserved for
that purpose.   No block or portion of ARIN's  final /8 allocation
will be used to satisfy a request for non-connected networks;  If
address space is unavailable for this purpose,  ARIN will treat it as
an unmet request under the provisions of 4.1.8."

> It needs to be unique among the networks they interconnect with and
> the networks those networks interconnect with.

> Now, when you consider that many of the networks they interconnect
> with may well interconnect with the internet... Guess what.

Networks that are non-connected are ones that by design do not have
any host on that network allowed to send or receive a packet  with a
source or destination address of another organization's network.

The networks you are describing that interconnect with multiple other
entities' networks are not non-connected networks. If an org declares
a network non-connected by design, in an IP address application, then
they are stating that  no transitive relationship they have between
their network  and other networks  will be allowed to connect their
network to further networks over IP.  If they have a plan to
interconnect with multiple other networks,  then the current
restrictions under NRPM 4.3.5 don't apply to them  in the first place,
 because they are making a connected network.

The networks that actually do interconnect may also be separate from
the network(s) used to perform the interconnection.    It's possible
for networks to connect together by transitive connections  _through_
a non-connected network;  in this case,   the interconnecting networks
 are not restricted by 4.3.5, and should have global IP address space,
   but  the  non-connecting network that attaches connected networks
together  does not require global IP address space.

They should be restricted to managed/shared private IP space by 4.3.5,
  they do not need global IP address space,  unless the networks
performing the interconnection are themselves interconnected, by


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