I joined CERN in 1971, at a time when theoretical high-energy physics was in a chaotic state. The field of "Data Communications" at CERN and elsewhere was equally chaotic. The variety of different techniques, media and protocols was staggering; open warfare existed between many manufacturers' proprietary systems, homemade systems (including CERN's own "FOCUS" and "CERNET"), and the rudimentary efforts at defining open or international standards. There were no standards for computer systems or for the communications between them. There were no LAN's, no PC's or Macintoshes, no Unix and no C programming at CERN.

In 1983, for the first time, a Data Communications (DC) group was set up in the CERN Data-handling Division (DD).  I was in the Software (SW) group, which had previously run many DD networking projects. The new DC group had a mandate to unify networking across the whole of CERN, but it soon became clear that this was not going to be done comprehensively. DC group decided to leave major parts of the field to others while it concentrated on building a CERN-wide backbone infrastructure. They also laid a formal stress on ISO networking standards, the only major exception being their support for DECnet. PC networking was ignored almost entirely. IBM mainframe networking (except for BITNET/EARN) remained in SW group. So did the work on electronic mail and news, and the new fields of Unix and workstation-based networking; as these were the areas in which the internet protocols were emerging, CERN's support for them would be uneven and contested for several years to come.

In August 1984 I wrote a proposal to SW group leader, Les Robertson, for the establishment of a pilot project to install and evaluate TCP/IP protocols on some key non-Unix machines at CERN including the central IBM-VM mainframe and a VAX VMS system. This was to decide if TCP/IP could indeed solve the problem of heterogeneous connectivity between the newer open systems and the established proprietary ones. The proposal was approved and the work led to acceptance of TCP/IP as a most promising solution, together with the use of "sockets" (pioneered by the BSD 4.x Unix system) as the recommended API.

In early 1985 I was appointed the "TCP/IP Coordinator" for CERN, as part of a formal agreement between SW group and DC group. DC's policy specifically restricted the internet protocols for use within the CERN site. No external connections were to be made using TCP/IP: here the ISO/IBM/DECnet monopoly still ruled supreme, and would do so until early 1989.

Between 1985 and 1988, the coordinated introduction of TCP/IP within CERN made excellent progress, in spite of the small number of individuals involved. The technologies concerned were basically simple and became steadily easier to buy and install. November 1985 brought a major step forward when LEP's management decided to use TCP/IP  for the control system on the 27-kilometre Large Electron-Positron Collider (LEP). This decision, combined with their later decision to use Unix-based systems, turned out to be essential for the success of LEP.

In 1988, the DC group (later renamed CS group in CN Division) finally agreed to take on the support of TCP/IP. What had been a shoestring SW group operation became a properly staffed and organized activity. CERN opened its first external connections to the internet after a "big bang" in January 1989 to change all IP addresses to official ones.

A key result was that by 1989 CERN's internet facility was ready to become the medium within which Tim Berners-Lee could create the World Wide Web. An entire culture had developed at CERN around "distributed computing", and Tim had contributed in the area of Remote Procedure Call (RPC), mastering several of the tools he needed to implement the web, such as software portability techniques and network and socket programming.

It is my personal belief that the web could have emerged considerably earlier if CERN had been connected earlier to the internet. Tim's first web proposal was written immediately after the opening of CERN's first external connection and Tim had been working with hypertext ideas since 1980, influenced by Ted Nelson's work on Xanadu among other things. But this remains in the realm of speculation. What is certain is that the internet provided a unique opportunity for some of us at CERN to take part in a series of events that changed the world for countless people and will continue to do so, hopefully for the better.

This is an edited and abridged version of Ben Segal's "Short History of Internet Protocols at CERN"