ARPANET standardized TCP/IP on this day in 1983 — 43-year-old standard set the foundations for today’s Internet
On January 1, 1983, ARPANET system architects initiated the cutover from the existing NCP to TCP/IP on all hosts.
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On January 1, 1983, ARPANET system architects initiated the cutover from the existing Network Control Program (NCP) with the Transmission Control Protocol/Internet Protocol (TCP/IP) on all hosts. The transition would be complete by June 1983. By 1984, over 100 universities and research facilities in the United States and Europe were connected using what is now regarded as the universal standard for global networking. TCP/IP became the foundation of the Internet as we know it.
Before this momentous decision, networks would use a mix of incompatible protocols and proprietary vendor stacks. NCP, which was displaced by TCP/IP, was designed to be ARPANET-only, and had no internetworking capabilities. With TCP/IP, an internetworking (and thus ‘Internet’) protocol was born, connecting these networks with those beyond their initial confines.
Beyond its internetworking power, TCP/IP was attractive across several other fronts. It was an open standard, which was vendor neutral, extensible, and free to implement. These features didn’t just make it a win for ARPANET, they provided the momentum that the entire world could get behind.
TCP/IP was designed by Dr. Vinton Cerf and Dr. Robert Kahn. It’s layered design also introduced innovations that would become essential to the evolution of the Internet. It boasted features like congestion control, end-to-end reliability, and would spawn future Internet-essential service protocols like HTTP, SMTP, DNS, and more.
If not TCP/IP, then what?
IBM famously described the era’s networking landscape as being like a Tower of Babel, with so many incompatible proprietary protocols clamoring for users. However, its own solution, dubbed SNA, was part of this proprietary problem. Similarly, Xerox would push forward the adoption of its XNS, and DEC its DECnet.
In contrast, the open, scalable, and hardware-agnostic TCP/IP managed to get a clear run at widespread adoption, and succeeded. One could say it won - not by being the best protocol designed to connect everything - but by being the only one. Additionally, its open and free nature, ability to run on everything from PCs to , allowed it to become the common denominator among a throng of multiprotocol network . These all added fuel to TCP/IPs success.
