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ICL Technical Journal Volume 6 Issue 3 TECHNICAL JOURNAL Volume 6 Issue 3 May 1989 Published by INTERNATIONAL COMPUTERS LIMITED at OXFORD UNIVERSITY PRESS ICL TCPU M IPA I The ICL Technical Journal is published twice a year by ' . International Computers Limited at Oxford University JOURNAL Press Editor J. Howlett ICL House, Putney, London SW15 ISW, UK Editorial Board J. Howlett (Editor) F.F. Land H.M. Cropper (F International) (London Business School) D.W. Davies, FRS K.H. Macdonald G.E. Felton M.R. Miller M.D. Godfrey (British Telecom Research (Imperial College, London Laboratories) University) J.M.M. Pinkerton C.H.L. Goodman E.C.P. Portman (STCTechnology Ltd B.C. Warboys (University and King’s College,) of Manchester) London) All correspondence and papers to be considered for publication should be addressed to the Editor. The views expressed in the papers are those of the authors and do not necessarily represent ICL policy. 1989 subscription rates: annual subscription £35 UK, £44 rest of world, US $88 N. America; single issues £17 UK, £22 rest of world, US $38 N. America. Orders with remittances should be sent to the Journals Subscriptions Department, Oxford University Press, Walton Street, Oxford 0X2 6DP, UK. This publication is copyright under the Berne Convention and the Inter­ national Copyright Convention. All rights reserved. Apart from any copying under the UK Copyright Act 1956, part 1, section 7, whereby a single copy of an article may be supplied, under certain conditions, for the purposes of research or private study, by a library of a class prescribed by the UK Board of Trade Regulations (Statutory Instruments 1957, No. 868), no part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means without the prior permission of the copyright owners. Permission is, however, not required to copy abstracts of papers or articles on condition that a full reference to the source is shown. Multiple copying of the contents of the publication without permission is always illegal. © 1989 International Computers Limited Printed by H Charlesworth & Co Ltd, Huddersfield ISSN 0142-1557 TECHNICAL Contents JOURNAL Volume 6 Issue 3 Foreword John Dickson 407 Tools, Methods and Theories: a personal view of progress towards Systems Engineering David E. Talbot 409 Systems Integration Roger Lucas 415 An architectural framework for systems P. Henderson and B. Warboys 435 Twenty Years with Support Environments Brian Warboys and Philip Veasey 447 An Introduction to the IPSE 2.5 Project R.A. Snowdon 467 The case for Case Fred Russell 479 The UK Inland Revenue operational systems E. Wilson 496 La Solution ICL chez Carrefour a Orleans Y. Pisigot 500 A Formally Specified In-Store System for the Retail Sector Val Jones 511 ... towards a Geographic Information System J.M.P. Quinn 542 ICL Technical Journal May 1989 j “Ingres Physical Design Adviser”: a prototype system for advising on the physical design of an Ingres relational database Michael Gunner 557 KANT — a Knowledge Analysis Tool Graham E. Storrs and Chris. P. Burton 572 Pure logic language Edward Bahh 585 The ‘Design to Product’ Alvey Demonstrator Dr. L.D. Burrow 598 Notes on Authors 617 i> ICL Technical Journal May 1989 Foreword It is now clear that Information and Information Systems are becoming the life-blood of organisations. The scale and impact of this is demonstrated in this issue, on the one hand by the experience at the Inland Revenue in the UK, where one of the largest databases in Europe is now regarded as a mere component in an organisa­ tion-wide system, and on the other by what is happening at the most recently-opened CARREFOUR hypermarket in France, where the closest integration of business needs and information systems is required for instant and local information on customer needs, stock optimisation and responsive price and margin management. These two examples are not isolated instances but are increasingly represen­ tative of the demands of our marketplace. This marketplace is one in which customers need to manage and specify such systems as a part of their overall business process, and in which ever-increasing standards of quality and reliability are demanded. It is appropriate therefore that this issue concentrates on system architec­ tures and integration. Clear demonstration is given of: — the scale and complexity of systems currently in use — the availability of formal methods for aiding the correct specification and implementation of these systems and — the emergence of concepts and formalisms to support the design and management of the complex integrated socio-technical systems that will be required in the 1990s. In addition, this issue vividly illustrates the impressive range of skills and experience available from ICL and its collaborators and the way in which advanced system theories and techniques can be rapidly applied to give real business advantage. John Dickson Managing Director, ICL Product Operations ICL Technical Journal May 1989 407 Tools, Methods and Theories: a personal view of progress towards Systems Engineering* David E. Talbot ICL Marketing and Business Strategy, Bracknell, Berkshire Introduction I am writing this paper from the standpoint of an Industrial consumer of Tools, Methods and Theories. As such, one needs to be clear that the overall goal of real interest is concerned not just with software engineering, or human factors, or the inclusion of “knowledge” in systems or devices but with the predictable construction of systems which usually contain all or at least very many of these constituent elements. It is, of course, a system that in the end a customer buys, not just its software or hardware or a knowledge base or the interfaces that it presents to its users. The overall goal of work in this field must therefore be Systems Engineering. The original Alvey Software Engineering Strategy certainly recognised this requirement from the outset. However, it also appreciated that we had a considerably less well founded position in Systems Engineering than in Software Engineering. In consequence, over its limited course of 5 years the emphasis of the programme was placed on developing and consolidating the Methods, Theories and Tools required to turn the business of producing software into a more predictable enterprise and one much less dependent on “wizards” and similar exotic creatures. Furthermore, Software Engineering was seen as a promising base from which a more general approach to building systems could be realised. I aim, therefore, to review: - how far Software Engineering has developed in terms of meeting its original more limited aims and how this contributes to the Systems Engineering goal. - how far associated disciplines concerned with hardware, with issues of the human interface and with knowledge based systems have moved to encompass also the “system” view. "This paper is based on an address given at the 1988 Alvey Conference; permission to publish it here is gratefully acknowledged. ICL Technical Journal May 1989 409 - and above all, how far these notions are really entering the industrial “soul” and having clear and measurable effects on providing customers with systems that meet their needs that is “Quality” systems. The Systems Company Let me start by proposing a view of “The Systems Company”. It is one that owes much to the thinking of Peter Cropper, Brian Warboys and others in ICL who have been worrying professionally about this subject for some years. A rather simple model would contain a number of quite straightforward notions: - first, a view of requirements, and one, moreover, that takes the view that the elicitation of requirements is a process that requires more than just sound systematic methods and good tools, but also some understanding and sympathy with the “market” being investigated. next, the recurring dream (nightmare?) of “components” and the notion of component re-use as still the major way in which both the quality of the finished system can be better assured and the productivity of the engineers can be raised. - last, the notion of dealing with components and processes over which the engineer has only limited control. It raises the issue of how design and engineering integrity can be established in an environment where the use of imported product components, and hence by implication their produc­ tion processes, needs to be considered the natural way of doing business rather than the exception. Perhaps, however, the more interesting features of such a model are concerned with points not recorded explicitly. These are: - that the model itself is recursive and is true for successive points on an integration chain where one man’s system must be considered simply as another man’s component. Thus at one end of the integration chain it may be concerned with etching silicon and at the other with, say, the production of a major C3 System. - that scale is a constant feature and that any method, theory or tool needs to accommodate itself completely to systems enterprises that are generally interesting only at levels measured in terms of tens of man years and involving the work of teams rather than individuals. - that since successive integration is an ever present reality the chances of needing to deal effectively with complexity are high. Against this background, let me now review developments so far. Software engineering Most software engineers would, I believe, have little difficulty in relating to the model described. However, most would also have some difficulty in 410 ICL Technical Journal May 1989 saying how current developments in methods, theories and tools have been of practical assistance to them in dealing with a number of the issues raised. In the area of design the notions of “design in the large(r)” are well established. Much good work has certainly been achieved in the develop­ ment of theories and methods concerned with helping deal more effectively with decomposition, improved modularity and binding, approaches to designing-in desirable properties such as reliability and such like.
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