ARIN-prop-320: /26 initial IPv4 allocation for IXPs

Date: 25 May 2023

Proposal Originator: Chris Woodfield

Problem Statement:

Per NRPM Section 4.4, ARIN has reserved a /15 for micro-allocations for critical internet infrastructure, such as internet exchange points (IXPs) and core DNS service providers. The majority of these allocation requests are made by IXPs. As of the last ARIN report, roughly half of this reservation is allocated (see https://www.arin.net/reference/research/statistics/#ipv4-reserved-pool-status-nrpm-4-10-ipv6-deployments). Projections from ARIN staff suggest that at current allocation rates, the remaining reserved space may be exhausted in the next few years.

In parallel, an analysis of PeeringDB data conducted by the RIPE Address Policy Working Group shows that approximately 70% of global IXPs have fewer than 32 members. An IXP this size could readily operate with a /26 allocation, which would provide 100% overprovisioning beyond their existing peer count. (Source: https://github.com/mwichtlh/address-policy-wg)

Unlike other types of allocations, IXP peering networks are not required to be globally reachable; only members of that IXP must be able to reach the prefix. As such, there is no requirement that an IXP allocation must be no smaller than a /24.

Policy Statement:

Existing text:

4.4. Micro-allocation

ARIN will make IPv4 micro-allocations to critical infrastructure providers of the Internet, including public exchange points, core DNS service providers (e.g. ICANN-sanctioned root and ccTLD operators) as well as the RIRs and IANA. These allocations will be no smaller than a /24. Multiple allocations may be granted in certain situations.

Replace with:

4.4 Micro-allocation

ARIN will make IPv4 micro-allocations to critical infrastructure providers of the Internet, including public internet exchange points (IXPs), core DNS service providers (e.g. ICANN-sanctioned root and ccTLD operators) as well as the RIRs and IANA. These allocations will be no smaller than a /26 for IXPs, or a /24 for other allocations that require global reachability of the assigned allocation. Multiple allocations may be granted in certain situations.

4.4.1 Micro-allocations for Internet Exchange Points (IXPs)

An IXP requesting an initial IPv4 allocation from this reserved space will be assigned a /26 by default. An IXP requesting an allocation larger than a /26 must show an immediate need to utilize more than 25% of the requested allocation size upon initial commissioning.

And IXP requesting an allocation under this section must have also requested, or already received, an IPv6 allocation for the same purpose under Section 6.10.1.

An allocation made to an IXP under this section may only be used for the operation of a public peering LAN. No other uses are allowed.

An IXP that has received an IPv4 allocation under this section may request a larger allocation once they have utilized more than 50% of their existing one. Upon receiving a larger allocation, the IXP must migrate to the new allocation and return their previous one to ARIN within 6 months of receiving the new allocation.

Comments:

This proposal mirrors RIPE policy proposal 2023-01 (see https://www.ripe.net/participate/policies/proposals/2023-01) which is currently under consideration in that region and appears to have sufficient community support for adoption at the time of this writing.

Timetable for Implementation: Immediate