Domain Name Services (DNS)

DNS is a network of servers that map Internet names to their numeric IP addresses.

The purpose of the NIH External Domain Name Service (DNS) is to provide authoritative resolution for NIH domains (such as nih.gov and the various subdomains such as cit.nih.gov). The focus of this service is Internet users and external systems attempting to access NIH data, not for internal computers within NIH. Internal resolution for NIH users is provided by the Dynamic Domain Name Service (DDNS).

The NIH External DNS service consists of three servers housed in physically diverse locations. Two are located within the main NIHnet network and a third (ns3) is located on the NCCS network in Sterling, VA. Since the NCCS network can operate entirely independent of the main NIHnet network, external systems will be able to resolve NIH domain information even if the entire NIHnet network is inaccessible. This model, adopted by all major Internet Service Providers, ensures NIH domains and IP addresses can be resolved in any number of disaster situations.

Visit the NIH Domain Name Service (DNS) home page for more information.