Transition to TCP/IP took place on 1 January 1983. The internet has officially celebrated its 20th birthday.
On 1 January 1983 the Advanced Research Projects Agency Network (Arpanet) of the US Department of Defence - the forerunner of the internet - was switched to the TCP/IP protocol. This enabled millions of computers to go online instead of the Network Control Protocol (NCP) which limited it to just 1,000 machines.
The TCP/IP protocol was designed by Vinton Cerf and Robert Kahn. On the mailing list of the Internet Engineering Task Force, internet pioneer Bob Braden wrote:
"The most logical date of origin of the internet is 1 January 1983, when the Arpanet officially switched from the NCP protocol to TCP/IP."
"Six months later, the Arpanet was split into the two subnets - Arpanet and Milnet [Military Network] - which were connected by internet gateways.
"There may still be a few remaining T-shirts about that read: 'I Survived the TCP/IP Transition'."
Braden added that some people would be surprised to discover that there were actually a few souls wanting to work on the TCP/IP changeover on 1 January. But they did.
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