Cogent Communications operates C.ROOT-SERVERS.NET as a public service to the Internet. First operational in 1987, C.ROOT-SERVERS.NET was known as C.NYSER.NET and was established at the request of the Internet Assigned Numbers Authority(IANA). In 1994, C.NYSER.NET became C.PSI.NET. PSINet, the first commercial ISP ever established, was operating the server when the root name server system started using the domain and thus became C.ROOT-SERVERS.NET. In 2002, Cogent Communications acquired PSINet's major U.S assets, which included responsibility for operation of C.ROOT-SERVERS.NET. To promote the vital development of global social and economic infrastructure, Cogent Communications has committed to the safe, reliable and secure operation of the root server for the benefit of the entire Internet. Instances of C.ROOT-SERVERS.NET are located in several locations throughout the United States and Europe.

Operational Principles

The purpose of this statement is to articulate certain general principles embraced by Cogent Communications with the primary goal of promoting public understanding and the continued sound operation of the root name server system. This statement is necessarily general and is not intended to prescribe new operating practices or binding expectations; rather, it is descriptive and reflects certain generally accepted understandings and practices. Cogent Communications is one of the operators which publish the root zone for the common good of the Internet community and strive to operate the root name service in the community's best interest.

Cogent Communications recognize IANA as the authoritative source of the root zone data published on the general Internet root name servers and acknowledge that the integrity of this data is essential to the sound operation of the root name server system. In our capacity as root name server operators, we neither possess nor exert any editorial control over the content of the root zone. Instead, our limited role is to publish the root zone without modification unless otherwise directed by appropriate authority.

In furtherance of the Internet community's best interests, Cogent Communications strive to make the investments in time and resources necessary to operate root name servers responsibly. In the event it becomes necessary to transition operational control to a successor operator, Cogent Communications will endeavor to provide the Internet community with advanced notice and take such other measures as may reasonably be necessary to facilitate a smooth transition.

Cogent Communications, as the operator of the root name server "C", recognizes the following organizations as current root name server operators and endeavors to coordinate operational service with them.


  • 2014‑03‑26 - IPv6 service address for (2001:500:2::C)


  • Bratislava, SK
  • Chicago, US
  • Frankfurt, DE
  • Herndon, US
  • Los Angeles, US
  • Madrid, ES
  • New York, US
  • Queretaro, MX
  • Paris, FR
  • Singapore, SG