"A Protocol for Packet Network Intercommunication"
Year First Appeared
1974
Creator
Vinton G. Cerf, Robert E. Kahn
A May 1974 paper by Vinton Cerf and Robert Kahn, published in IEEE Transactions on Communications, that introduced a single shared protocol for joining together independent packet-switched networks. The design described here became the technical foundation of the internet; four years later, it was split into the two layers we now know as TCP and IP.
Importance in Internet Culture
The paper articulated the idea of "internetworking" — connecting separately designed networks (the ARPANET, a packet radio network, a satellite network) into a single virtual network using a shared protocol and a new device the authors called a "gateway," which the world would later call a router. It established the end-to-end principle that still defines the internet: the network's job is to move packets; reliability, ordering, and flow control belong to the endpoints. Cerf and Kahn shared the 2004 Turing Award largely on the strength of the ideas first written down here.
Interesting Fact
What Cerf and Kahn originally proposed was a single protocol called the Transmission Control Program. It wasn't until 1978, after running the protocol over real networks, that researchers split it into two layers — TCP for end-to-end reliability, IP for routing and addressing — producing the "TCP/IP" name that stuck. The paper also introduced ideas that took decades to feel ordinary, like variable-length packet headers, end-to-end checksums, and fragmentation across networks with different maximum packet sizes. Cerf and Kahn described what they were proposing as a "protocol skeleton," explicitly expecting it to evolve as networks did.