4. A Brief History of the Dial-up Service

Now known more by its more Politically Correct name of the Dial-in Service, it has been around for nearly as long as OUCS has been located at 13 Banbury Road. A small number of large Post Office devices (the precursors of what came to be known afterwards as Modems - MODulation/DEModulators) were attached to the 7906 Communications Processor that handled up to 32 ASR Teletype terminals for the 1906A Central University Computer installed in 1971. The remote user devices were Acoustic Couplers that accepted a standard GPO handset placed into foam cups inside a smart wooden box after the telephone call to the OUCS equipment had been made. This link worked at an amazing 110 baud and these devices were the wonder of the age at the time.

Later the Modular One front-end (7905) would handle 300 baud lines and a Racal unit rack provided remote connectivity for as many as 5 simultaneous remote users. Security was, in those innocent days, covered to everybody’s satisfaction by the plain-text George III operating systems username and password. You have to remember that at that time the remote connections were mainly other computers: the personal computer was a (very) rich scientist’s toy costing at least the equivalent of one and a half years salary of us lesser mortals who had to make it all work.

The early PC boom years of the late 70s/early 80s saw the rise of the ICL 2900 and DEC VAX machines and a gradual dial-up equipment change from 300Bd through 1200, 2400, 4800 and finally 9600Bd handled post-1984 by first Gandalf PACX IV, followed by the Gandalf 2000 StarMaster asynchronous switch in 1986. By this time there were around 10 BT lines to play with connected to the famous Zoom 14.4 kBd modem sets.

In early 1996 the demand for multiple lines, the availability of an alternative telephone company to BT (ComTel) and the relief in the knowledge that now OUCS wasn’t the only entity in the business of digging up Oxford’s hallowed pavements led to the purchase of two Ascend MAX dial-up servers, one to handle 15 BT lines and a second to handle 15 ComTel ones via ISDN 30 multiline circuits. The additional requirement for ISDN connectivity was met by introducing a third MAX unit for the DataCentrix service that allowed small related units such as Energy Studies and Richard Dawkin’s offices to connect to the University backbone with multiple users. With staggering originality we named these boxes MAX1, MAX2 and MAX3. The process of hand-registering usernames and passwords had been an increasingly intensive and time-consuming chore, so these new MAXen were equipped with RADIUS servers linked to the Registration Server, thus automating the registration and authentication processes and providing connectivity logs, the content of which occasionally featured in various Proctors’ disciplinary hearings as College Bursars seemed to regard the service as the perfect opportunity to avoid the expense of data wiring in student rooms.

The service continued to grow and peaked at 150 lines split between BT and NTL (ComTel having gone through various name changes) plus a further 15 ISDN DataCentrix lines. The base hardware was renewed at huge expense around 1999 with the introduction of the final V32(bis) series protocol modems. The DataCentrix service was the first to become redundant and MAX2 was removed quietly and now slumbers in our Workshop, awaiting a call that will probably now never come. As each line continues to cost us £12 per month and with the number of lines actually needed now reduced to 18, the majority of remote users now coming in via broadband and as the Ascend MAX has not been maintainable for at least 5 years now we feel that it is about time to retire MAX1 and MAX3.

At 15 years old they have provided the most long- lived production service on the same hardware that we have ever offered - it is indeed time to say “Goodbye and Thanks!”

Geoff Lescott, University Network Controller

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