Policy Proposal 2004-1: Defining Utilization of IPv4 Addresses

Status: Abandoned

Tracking Information

Discussion Tracking

Mailing List:

Formal introduction on PPML on 17 March 2004

Public Policy Mailing List

ARIN Public Policy Meeting:


ARIN Advisory Council:

20 April 2004

ARIN Board of Trustees:

BoT Meetings




Michael Dillon
  1. When an ISP applies for IPv4 address space, ARIN analyzes the utilization rate of any existing IPv4 address blocks allocated to the ISP.
  2. For the purposes of calculating the utilization rate of ARIN allocations, any IPv4 address range that is assigned or allocated by the ISP to another organization will be counted as utilized if it meets the following two conditions.
  3. The assigned or allocated address range must be of a size that is justified by ARIN policy.
  4. The ISP must require the other organization to use their addresses efficiently, in particular by using VLSM and CIDR technologies.
  5. The utilization rate of an address block is calculated as the number of utilized addresses divided by the total number of addresses in the block.

Currently, there is no clear definition of utilization in ARIN's IPv4 policy. The result is that different organizations interpret this in different ways. This policy change is an attempt to level the playing field so that noone has an unfair competitive advantage due to the vagueness of the policy.

This policy change only provides a clear definition for the utilization rate of address blocks allocated by ARIN to ISPs. It does not address the utilization rate of address blocks assigned to end users which would presumably be calculated differently by counting end devices, network and broadcast addresses.

Timetable for implementation: 30 days after ratification