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National Library of Medicine Ramps Up for Full Deployment of Internet Protocol version 6 (IPv6)

Newest Version of Principal Computer Communications Protocol Provides More IP Addresses, Other Upgrades


The National Library of Medicine (NLM), the world's largest medical library and a component of the National Institutes of Health (NIH), is well on its way to completing a project to provide access to its public information services via native IPv6 (Internet Protocol version 6). IPv6 is an updated and improved Internet communications protocol, succeeding the 30-year-old IPv4, the current default Internet protocol. Although IPv6 will eventually replace IPv4, NLM, like most information providers, will support both IPv4 and IPv6 protocols for years to come. This will ensure access to the Library's electronic resources via both legacy and new technologies.

NLM is phasing in the availability of IPv6 support on an application-by-application basis. The following are applications that were activated for IPv6 during February 2012: 

Access to additional NLM applications will be enabled for IPv6 in the future. To learn the status of NLM applications with IPv6 support, go to: .

NLM will also join leading Internet companies in the World IPv6 Launch event June 6, 2012. World IPv6 Launch is a follow-up to the successful IPv6 Day, a global 24-hour test that NLM participated in on June 8, 2011. Participants in the IPv6 Launch are required to have IPv6 available on or before June 6th. NLM's National Center for Biotechnology Information (NCBI) is planning to make the FTP download site ( production for World IPv6 Launch date, replacing the current FTP test version.

With the global explosion in the number of Internet-enabled devices, organizations and Internet Service Providers have had to expand their networks, which has meant a dramatic spike in the number of IP addresses needed. In February 2011, the Internet Assigned Numbers Authority (IANA) allocated the last remaining IP addresses to regional authorities. Although the central IPv4 pool has been depleted, IPv6 offers a vast number of addresses - some calculations approximate 666 trillion addresses available per grain of sand on earth, to the depth of one mile. The transition to IPv6 from IPv4 will allow the Internet to continue its amazing growth with no danger of running out of IP addresses.

For the near future, IPv6 and IPv4 will co-exist on the NLM network and be transparent to end users. Modern software clients on end-user computing devices are capable of automatically negotiating the use of IPv4 or IPv6 on behalf of the user. By providing native IPv6, NLM allows IPv6 customers the ability to reach NLM applications without having to transverse the IPv4 pathway.       

For additional detailed information about IPv6, please visit: