[arin-ppml] Sensible IP Allocations Revision 0.9
owen at delong.com
Wed Dec 1 17:44:19 EST 2010
Here is the revised text of proposal 121. Changes in this version:
2. Improved definition of ISP/LIR to close loophole for multihomed
This is version 0.9 of the proposal:
Amend section 2 as follows:
Delete section 2.9 (Obsolete)
Replace section 2.10 with the following:
2.10 The term End Site shall mean a single structure or service delivery
address, or, in the case of a multi-tenant structure, a single tenant
within said structure (a single customer location).
Add the following:
2.12 The term serving site shall mean a location where an ISP terminates
or aggregates customer connections, including, but, not limited to
Points of Presence (POPs), Datacenters, Central or Local switching
office or regional or local combinations thereof.
2.13 The term provider assignment unit shall mean the prefix of the
smallest block a given ISP assigns to end sites (recommended /48).
2.14 The term utilized shall have the following definitions:
(i) A provider assignment unit shall be considered fully utilized when
it is assigned to an end-site.
(ii) Larger blocks shall have their utilization defined by dividing the
number of provider assignment units assigned from the
containing block by the total number of provider assignment
units. This ratio will often be expressed as a percentage
(e.g. a/t*100, for a /36 3072/4096 * 100 = 75% utilization)
Replace sections 6.5.1 through 6.5.3 with the following:
(a) The terms ISP and LIR are used interchangeably in this document and
any use of either term shall be construed to include both meanings.
(b) The term nibble boundary shall mean a network mask which aligns
on a 4-bit boundary (in slash notation, /n, where n is evenly divisible
by 4, allowing unit quantities of X such that 2^n=X where n is
evenly divisible by 4, such as 16, 256, 4096, etc.)
6.5.2 Initial Allocations to LIRs
(a) All allocations shall be made on nibble boundaries.
(b) In no case shall an LIR receive smaller than a /32
unless they specifically request a /36.
(c) The maximum allowable allocation shall be the smallest
nibble-boundary aligned block that can provide an equally
sized nibble-boundary aligned block to each of the
requesters serving sites large enough to satisfy the needs
of the requesters largest single serving site using no more
than 75% of the available addresses.
This calculation can be summarized as /N where
N = 48-(X+Y) and X is a multiple of 4 greater
than 4/3*serving sites and Y is a multiple of 4
greater than 4/3*end sites served by largest serving site.
(d) For purposes of the calculation in (c), an end site which
can justify more than a /48 under the end-user assignment
criteria in 6.5.8 shall count as the appropriate number of /48s
that would be assigned under that policy.
(e) For purposes of the calculation in (c), an LIR which has
subordinate LIRs shall make such allocations according
to the same policies and criteria as ARIN. In such a case,
the prefixes necessary for such an allocation should be treated
as fully utilized in determining the block sizing for the parent LIR.
(f) An LIR is not required to design or deploy their network
according to this structure. It is strictly a mechanism to
determine the largest IP address block to which the LIR
An organization qualifies for an allocation under this policy if
they meet any of the following criteria:
(a) Have a previously justified IPv4 ISP allocation from ARIN
or one of its predecessor registries or can qualify for
an IPv4 ISP allocation under current criteria.
(b) Are currently multihomed for IPv6 or will immediately
become multihomed for IPv6 using a valid assigned
global AS number and will be making reassignments
to other organizations.
(c) Provide ARIN a reasonable technical justification,
indicating why an allocation is necessary, including
the intended purposes for the allocation, and describing
the network infrastructure the allocation will be used to
support. Justification must include a plan detailing assignments
to other organizations or customers for one, two and five year
periods, with a minimum of 50 assignments within 5 years.
6.5.3 Subsequent Allocations to LIRs
(a) Where possible ARIN will make subsequent allocations by
expanding the existing allocation.
(b) An LIR which can show utilization of 75% or more of their
total address space, or more than 90% of any serving site
shall be entitled to a subsequent allocation.
(c) If ARIN can not expand one or more existing allocations,
ARIN shall make a new allocation based on the initial
allocation criteria above. The LIR is encouraged, but not
required to renumber into the new allocation over time
and return any allocations no longer in use.
Replace section 6.5.4 with the following
6.5.4 Assignments to end users shall be governed by the same
practices adopted by the community in section 6.5.8 except
that the requirements in 220.127.116.11 do not apply.
Add the following to 6.5.7
LIRs which received an allocation under previous policies which is
smaller than what they are entitled to under this policy may receive
a new initial allocation under this policy provided that they agree to
renumber into that new allocation and return their prior allocation(s)
within 5 years. If possible, ARIN will simply expand their existing
allocation rather than requiring renumber and return.
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