Louis Pouzin

Louis Pouzin

Louis Pouzin, born in 1931, is a French engineer who invented the CYCLADES computer network and its datagram packet-switching network, from which TCP/IP was derived. Having studied at École Polytechnique in Paris, Pouzin worked on one of the world’s first time-sharing systems at Massachusetts Institute of Technology (MIT) in the mid-1960s. He wrote a program called RUNCOM, the first operating system ‘shell’: an idea that led to the first shell that ran atop UNIX, the operating system that would spread the idea across the computing world.

Pouzin joined the Delegation a l’Informatique in 1971 and returned to the US to meet people involved with ARPANET, including Vint Cerf. In the early 1970s, Pouzin invented the datagram (a data telegram) and CYCLADES, the first network to make the host computers responsible for the reliable delivery of data, rather than the network, in a bid to overcome the limitations of the ARPANET design. He conducted the first demonstration in 1973 and continued to refine the network, which undoubtedly contributed to the way the Internet works today.

Pouzin is currently Project Director with EUROLINC, an association promoting the use of native languages on the Internet. He was named a Chevalier of the Légion d’Honneur by the French government in 2003 and inducted into the Internet Hall of Fame in 2012.


The Internet and the World Wide Web have revolutionised the way we communicate and enabled the creation of whole new industries.