The document discusses the depletion of IPv4 addresses and the need to migrate to IPv6. It makes the following key points: 1) IPv4 addresses are being depleted as seen by utilization and trend data, so migration to IPv6 is necessary to ensure ongoing availability of contiguous IP address blocks. 2) All stakeholders - enterprises, internet service providers, equipment vendors, and content providers - need to begin supporting both IPv4 and IPv6 now to ensure full interoperability during the transition and avoid being unable to connect to an IPv6-only internet in the future. 3) Specifically, enterprises should make their services reachable over IPv6, ISPs should begin connecting customers with both IPv4 and IPv6

1. IPv4 depletion and migration to IPv6 John Curran Chairman American Registry of Internet Numbers (ARIN)

4. IPv4 - Address Space Utilization ARIN IPv4 Depletion

5. IPv4 - Address Space Trend ARIN IPv4 Depletion