CAMBRIDGE COMPUTING The First 75 Years Haroon Ahmed Computer Laboratory CAMBRIDGE COMPUTING Th e First 75 Years CAMBRIDGE COMPUTING Th e First 75 Years Haroon Ahmed © 2013 Cambridge Computer Laboratory and Third Millennium Publishing Ltd First published in 2013 by Third Millennium Publishing Limited, a subsidiary of Third Millennium Information Limited 2–5 Benjamin Street London UK EC1M 5QL www.tmiltd.com ISBN 978 1 906507 83 1 All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any storage or retrieval system, without permission in writing from the publisher. British Library Cataloguing in Publication Data: A CIP catalogue record for this book is available from the British Library. Written by Haroon Ahmed Photography by Alan Davidson Managing Editor, Susan Millership Editorial assistance by Neil Burkey Designed by Matthew Wilson Production by Bonnie Murray Reprographics by Studio Fasoli, Italy Printed by Gorenjski Tisk, Slovenia Contents Preface 6 Foreword 8 1 Babbage’s ‘Magical Machines’ 10 2 The Genesis of the Computer Laboratory 20 3 Maurice Wilkes: Computer Pioneer 34 4 Maurice Wilkes and the EDSACs 44 5 Maurice Wilkes: New Directions of Research and the End of an Era 66 6 Computing for All: Networking the University from 84 EDSAC Users to Desktops and Laptops – David Hartley 7 Spreading the Word: Teaching Computer Science 94 and Technology – Peter Robinson 8 The Computer Laboratory, 1980–2012: 104 The ‘Needham Years’ and the Modern Era 9 Entrepreneurs, Spinning Out, Making Money and 122 Linking with Industry 10 The Computer Laboratory on its 75th Birthday: 142 A Centre of Research Excellence Bibliography 162 List of Subscribers 166 Index 170 Acknowledgements and Picture Credits 176 Preface ambridge Computing is an illustrated history celebrating the 75th anniversary of the foundation of Cthe Computer Laboratory on 14 May 1937 and marks the 100th anniversary of the birth of Professor Sir Maurice Wilkes on 26 June 1913. Remarkably, the history of the Laboratory began almost a decade before the fi rst modern electronic computer was built. Professor Sir John Lennard-Jones, founder and fi rst Director of the Mathematical Laboratory (now Computer Laboratory) had the foresight to recognise that numerical methods would become increasingly important in all branches of science, but the central fi gure of this commemorative book is Professor Sir Maurice Wilkes, who reigned over the Laboratory for three and a half decades. In his obituary by the BBC, Wilkes was nominated the ‘Father of British Computing’, a perfect accolade for a true computer pioneer, and three chapters here describe his early career, his work in the era of mainframe computers and his last 15 years of research before retirement. At the heart of the book is an account of the seminal achievement of the Laboratory, the construction and commissioning of EDSAC, the fi rst stored-program digital computer to come into regular service. Although this book is primarily about the Computer Laboratory it does not ignore two great giants of computing, Charles Babbage and Alan Turing, who were both Cambridge men. Babbage conceived mechanical digital computers with almost all the features of a modern stored-program computer nearly 100 years before electronics made it feasible to build practical computers; while Alan Turing is, undoubtedly, the most famous computer scientist of all time and a national hero in the UK. Short accounts of the life and work of these two great men are included in the book. 6 Preface The early remit set by the University for the By 1980 computers had become ubiquitous and Computer Laboratory was to provide a computing the Computer Laboratory had to expand and modernise service to the University, and its history is outlined by its research to keep up with the extraordinary advances David Hartley, the first Director of the Computing taking place in computer science and technology. Its third Service. Undergraduate teaching is an essential activity Director, Professor Roger Needham, led the Laboratory in any university and from its earliest days the Computer for 16 years into the modern era, and towards the end of Laboratory took this commitment to heart. Peter his tenure he helped the University to secure a benefaction Robinson describes the evolution of Computer Science from the William Gates Foundation for a splendid teaching in chapter seven. new building to house the Laboratory. Since then the Laboratory’s research has gone from strength to strength and the last chapter of the book demonstrates the great range and depth of the current research programmes. Although teaching and research are the main activities in the Computer Laboratory it also prides itself on the culture of entrepreneurship it instils into many of those who graduate with a degree in Computer Science. A chapter is devoted to the Laboratory’s formal and informal links with industry and to the spectacularly successful business ventures of some of its alumni. Throughout the writing of the book it has been necessary to balance the historical content against technological details. The choices have been difficult to make but in a book of 176 pages with a large number of illustrations it was necessary to restrict technical details to the essentials. This book could not have been written without the support and cooperation of members of the Laboratory past and present, and they are acknowledged at the end of the book. Documentary sources and the oral evidence from interviews are included in a bibliography. On a personal note, it was necessary to keep to strict deadlines to ensure that the book could be published on the 100th anniversary of the birth of Maurice Wilkes. Writing hours were long and interrupted only when Keir Nizam, aged three, came to visit and demanded to play with his grandfather, bringing a welcome respite. And finally, my wife Anne read all my first drafts and improved them immeasurably with her comments and corrections. Haroon Ahmed January 2013 Professor Ahmed is Visiting Professor at the Computer Laboratory. 7 Foreword Cambridge Computing is more than just the story of computing in Cambridge. Professor Haroon Ahmed sets his history in the broader framework of how calculators and computers evolved worldwide. He also describes how computer technology has been commercialised, using 12 successful companies that have spun out of the Cambridge Computer Laboratory as examples, and provides an update on what is happening in computer research by describing current research in the Computer Laboratory. Th e fi rst electronic computers were built to improve our ability to calculate, to outperform mechanical calculating machines. It was clear from the start that electronic switches, initially using radio valves, would be faster than mechanical mechanisms and that they could be used to build faster calculators, but no-one predicted that through the use of semiconductor integrated circuits these calculators would become so powerful that they would impact upon almost every aspect of human life: the way we communicate, travel, entertain ourselves, grow food, design buildings, improve our health, and so on. Th ere is little that computers have left untouched, and it seems amazing that they did not exist 76 years ago. How to build the fi rst machines, however, was anything but clear. It was a daunting task, highly complex and fi lled with unknowns. Haroon Ahmed tells the story from the beginning, starting with mechanical calculating machines, and then describing how Cambridge’s fi rst stored-progam electronic machine, EDSAC, was built by Maurice Wilkes and his team. He tells how others were making excellent progress in the UK in Manchester, and that in the USA they were operating on a much larger scale, but Wilkes’s small team kept up with the pace and was the fi rst to use their computer in a routine manner to help scientists and engineers in their research. Lord Broers was Vice-Chancellor of Cambridge University, 1996–2003. 8 The William Gates Ahmed’s explanations of how these early machines the computer industry was able to provide the resources Building is the home of the Cambridge University were built are clear and readily understood by non-experts. and the standardisation and Cambridge along with other Computer Laboratory. Occasionally he goes into a depth that may be difficult leading universities purchased rather than built their for the layman but only when it is necessary to explain computers. Similar situations have been reached in other the sequence of events, and even in these cases it doesn’t science-based technologies and when this occurs future interrupt the narrative. In the beginning the pioneers success depends on universities and industry working concentrated on building machines. Their attention closely together. Cambridge excelled in its collaborations then shifted to the way the machines were used, and to with industry and has therefore remained among the educating those who could benefit from them. The next world leaders in computer research. step was to link machines together in rings and networks Professor Ahmed carefully and completely describes thereby connecting scientists and engineers, firstly in the evolution of computers going back and forth in time different laboratories in Cambridge, then around the UK as he alternates between describing technical progress and finally around the world. These ‘networks’ eventually and talking about those who made it happen. He has led to the Internet. produced a volume that is a good read for anyone who In the late 1960s it became apparent that there was wants to learn how things work in the 21st century, a no point in universities continuing to build their own must read for those who are working on the advancement computers. The resources required to remain competitive of computers, and a valuable reference book for historians became too great for universities, and users around of science and technology.