Department of Defense
High Performance Computing Modernization Program

Internet Protocol (IP) version 4 (IPv4) is about forty years old. This critical part of the Internet’s infrastructure is approaching its end of life, as the American Registry for Internet Numbers issued the last remaining IPv4 addresses in its free pool on September 24, 2015. This won’t have an immediate impact on the way people use the Internet, but both the exhaustion of IPv4 addresses and the efforts to deploy IPv6 addresses are impacting the way United States Federal, state, and local government organizations, academic institutions and commercial businesses use the Internet.

The impact of IPv4 address exhaustion on Internet use is described in this 2018 roundup of the state of the Internet by Geoff Huston, while the impact of IPv6 address deployment on Internet use is described: 

A first time visitor to the IPv6 Knowledge Base might want to explore the Initial Introduction article in the General Information section and the Frequently Asked Questions section in the column to the left, and then look at the Overview articles in the General Information and Deployment sections. Someone just starting to think about deploying IPv6 or in the early phases of a deployment might want to explore the Before you Begin article in the Deployment section.

Additional IPv6 Knowledge Base highlights include:

DREN started supporting IPv6 in June, 2003, when it was designated as the first Department of Defense (DoD) IPv6 pilot network by the Assistant Secretary of Defense (Networks and Information Integration)/DoD Chief Information Officer [ASD(NII)/DoD CIO]. By July, 2005, the entire DREN wide-area network was routinely supporting end-to-end IPv6 traffic, sites were supporting IPv6 along with IPv4, and selected applications were IPv6 enabled. DREN has provided its users with servers, services and client applications using IPv6 since then. During the worldwide deployment of IPv6, DREN will continue providing a secure, high-performance IPv6 infrastructure with legacy support for IPv4.

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