Peter T. Kirstein
Peter Thomas Kirstein (né Kirschstein; 20 June 1933 – 8 January 2020) was a British computer scientist who played a role in the creation of the Internet. He made the first internetworking connection on the ARPANET in 1973, by providing a link to British academic networks, and was instrumental in defining and implementing TCP/IP alongside Vint Cerf and Bob Kahn.