Skip to content

Policy Block: Draft Policy ARIN-2025-8: Reserve 4.10 Space for In-Region Use#

ARIN 57 Public Policy and Members Meeting digest Program Adjacent pick 20–22 April 2026

Abstract Slides Recording

E. Marie Brierley (with Kaitlyn Pellak), ARIN Advisory Council

Play the recording: Policy Block: Draft Policy ARIN-2025-8: Reserve 4.10 Space for In-Region Use

  • Why: The policy counterpart to the RIO fraud report — 4.10 space (the IPv4 block reserved to facilitate IPv6 deployment) is one of the documented abuse vectors, and this codifies the in-region restriction.
  • What: Amends Section 4.10 to state the set-aside is dedicated to facilitating IPv6 deployment within the ARIN service area. Staff review confirms this codifies existing practice with no operational impact. The live controversy is scope: PPML commenters noted the vague wording could block legitimate uses — e.g., an org with a globally-used ARIN IPv6 allocation using its 4.10 IPv4 to provide NAT64 for that global v6 space.
  • How: A two-word textual amendment; the interesting question posed to the community is whether "only" should be specified.
  • Where applicable: ARIN-region policy; matters mainly to orgs holding or seeking 4.10 space — which, per the RIO report, includes the more inventive lessees.