Early Broadband Service Trials: The Cambridge iTV trial

1994-96. ATM Ltd (later renamed Virata Inc) and Online Media, Cambridge UK.

Link to a local radio article about `Home Shopping Services'.

Architecture of the iTV trial

The Cambridge Digital Interactive Television (iTV) Trial started in September 1994, with ten users connected in the first phase. ATM networking technology was employed throughout the system, with two-way digital data being carried alongside cable TV signals over fibre optic links. In phase two, begun in March 1995, the network and the content server facilities were substantially enhanced, and the number of user sites (homes, schools and businesses) was increased: by January 1996 it approached one hundred.

E1 G.80x ATM Line Card NIC

The above E1 network interface card (NIC) design was used in the set-top boxes of the iTV Trial. Nearly 100 such were installed in homes and schools in Cambridge. We used an E1 baseband signal running on the CATV feeder coax from the street cabinet to each home. The analogue CATV occupied the upper frequencies as usual. I (djg) designed this card, code named LUCY, using two Xilinx devices because each device had two global clock networks and I needed a total of four clock domains.

The FPGA designs for the NIC saw the first real use of my CSYN Verilog compiler. This was probably a world first, being both the first academic and first commercial instance of programming an FPGA using RTL.

The Wild Vision production run of the Line Card NIC was exactly the same as my design except they used a new PCB layout: Wild Vision NIC.

First fibre-to-the-home in Cambridge?

The first few houses added to the trial had a dark fibre from the Online Media building. An optical-to-electrical convertor was needed to connect the STB in the house. This is explained in the following video (duration 1:30, excluding 30 second epilogue) recorded in the "Street" of the William Gates Building at the launch of the Computer Architecture Research Centre, June 2024. A fibre-to-the-home first?

Later connections in the trial mostly used fibre-to-the-kerb (FTC) technology, with an ATM switch in the kerbside.

Fast forward to 2023, when fibre-to-the-home (FTH) became a commercial reality in Cambridge. If Cambridge Fibre connect to Brian Knight's house they'll find he already has a fibre!

Online Media Set-top Box

Here is one of the set-top boxes from the trial (courtesy BJ Knight). The IR remote controller was custom designed for us by Allen Boothroyd of Meridian Audio.

Set-top box internal view:

The Lucy ATM card is top centre. The two ROMs, top left, contain RISCOS V3.5.

Press cuttings and so on

• `Cambridge Corners the Future' in Networking Volume 05, No.10, Nov 95.

• Agenda for Action in the UK, Visit to Acorn Online Media, Cambridge, Wednesday 22 May 1996     CACHED.

• `Cambridge Consumers Move Into 21st Century with Interactive TV', Phase 2 Press Release, 30th March 1995. CACHED.

• `Consumer interactivity in Cambridge', Nigel Harper. Multimedia Applications, Services and Techniques — ECMAST '97 Lecture Notes in Computer Science, 1997, Volume 1242/1997, 581-592, DOI: 10.1007/BFb0037377

• `Moving Towards Interactive TV - The Trial in Cambridge' Chris Keen, Online Media. Full text via SAGE.

• `The Cambridge Digital iTV Trial.' DJ Greaves and M Taunton. CAM TRIAL.

• `Cambridge Corners the Future in Networking.' Tony Krzyzewski. LINK1, LINK2, LINK3.

• `The Superhighway in Action: the Cambridge Trial'. G. Vincent, in IEE Review (Volume: 41 , Issue: 3 , 18 May 1995) UK companies are at the forefront of world efforts to bring the communications revolution to the home. The author describes a comprehensive ATM-based trial currently running in the UK. The first phase of the trial was set up to solve the technical issues involved in setting up and operating a low cost, fully switched ATM-end-to-end infrastructure capable of delivering a wide range of information types, up to and including video. It also explored the basic logistics of service provision, including for example, a regularly updated news-on-demand service. The second phase extends the number of users and implements some cost reductions in the technology employed, but also focuses on the development of services. For this expansion of the trial an environment has been created (the 'Service Nursery') for development and trialling of the new generation of multimedia services that will make the superhighway a commercial reality.
          PDF.

• `Realising the Broadband Access Future' by James F Kelly of BT. in `Broadband Access and Network Management: NOC'98' ISBN=9051994001. Edited by D. W. Faulkner, A. L. Harmer - 1998.

• Family at forefront of TV `revolution' Cambridge Evening News , 4th October 1994 (Courtesy BJK).
  

• Electronics Weekly, `Spotlight: Video-on-Demand via Satellite'. June 7 1995.
  An interview with Malcolm Bird of Online Media (Courtesy BJK).
  

• `Multimedia Milestone'. Financial Times, 1st March 1995 (Courtesy BJK).
  

• `Interactive TV Tempts Viewers'. Philippine Star, 24th Feb 1995 (Courtesy BJK).
  

• Online Media Press Release (Courtesy BJK).
      PDF.

• `TV that thinks it's a Video'. Daily Telegraph, 11th October 1994 (Courtesy BJK).
  

• `An engaging message for couch potatoes'. The Times, 28 October 1994 (Courtesy BJK).
  

NYT Contemporaneous Article

`In Old England, A Silicon Fen, Cambridge as a High Tech Outpost'. Not related specifically to the iTV trial, a 4th Jan 1998 NYT article on Silicon Fen. Highlighting Mount Pleasant House, where ATML and Virata were based, and featuring Computer Lab alumni Mike Muller (Arm) and Adrian Wrigley (Computer Lab Rainbow Group).
    (Courtesy BJK).
The photo taken in New Court St John's shows, front-row L-to-R, Roger Needham, Robin Milner, Bill Gates and Alec Broers.

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