Link 11 ( v. Engl. Connection for link ) denotes a military data exchange standard for data links to NATO, which is used especially in the Navy, but also in parts in the Air Force (Link 11B).

Link 11 was designed in 1955 by the U.S. Navy and the U.S. company Rockwell Collins and serves the automated exchange of information between the situational leadership systems of ships and aircraft. Link 11 is laid down with its data definitions and the rules and regulations in Standardization Agreement STANAG 5511.

Link 11 uses UHF and HF radio links for transmission of digital information, with a Net Control Station are all located in the network units sequentially interrogates (Full Roll Call ). Because of its susceptibility to interference and low data rate, it is now technically obsolete. 1975 began the developments to link 16 and the U.S. Navy delivered the first Link 16 applications mid -1990s from. Nevertheless, the link 11 in many navies continues to serve as the primary source of information for the management image exchange and issue of orders in real time.

Since 1992 it is, Link 22 (also known as NATO Improved Link Eleven; NILE ) to develop, to replace Link 11 and Link 16 in the future.

Link 11B is based on a direct connection, where two peers exchange data.