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Viable Computing Systems Viable Computing Systems: A Set Theory Decomposition of Anthony Stafford Beer’s Viable System Model; Aspirant of Surpassing Autonomic Computing Ruth Thompson A thesis submitted in partial fulfillment of the requirements of Liverpool John Moores University For the degree of Doctor of Philosophy May 11 Abstract This thesis articulates a novel technology: Viable Computing Systems (VCS) [1], which promotes viability within self-managing computing systems. The research momentum was rising software system complexity within the software industry today [6, 7]. Autonomic Computing [8] has been proposed as a solution to this, yet this research advances into the genre of Viable Computing Systems (VCS) by presenting a conceptual model characterizing homeostatic [9] self-governance, thereby innovating within the genre. By examining cybernetic, mathematical, biological and computing techniques, a first-stage, functional, decomposition of Stafford Beer's cybernetic Viable System Model (VSM) is presented from the viewpoint of dually modelling the relationships between the recursive levels of the VSM and between the component systems. By endorsing autonomy versus governance, this research presents a tangible formalism conceptualising homeostasis [9]. This research uniquely presents an algebraic, atomically derived, emergent model that reflects a set theory decomposition of the VSM. This is pertinent by its composition of multiple, yet independent entities sharing one or more objectives. Although the original scope of the VSM was that of human organizations, this work digresses towards its application to autonomic computing system design. The potential to deliver self-managing systems based upon the principles of the human autonomic nervous system is exposed. Since its inception, scope for progression still exists, thereby enabling the presentation of this innovative research that applies a cybernetic approach to the extension of the aforestated software architectural style. 2 Overall, the thesis presents an expressive grammar as a reference framework, using Beer's VSM as a vehicle to augment the state of the art of autonomic computing into the original field of Viable Computing Systems. This progresses the state of the art by offering an original framework that has the future potential to be translated into code and thus feasibly executed in a real world situation. Case studies demonstrate a theory of how inherent learning and control is sought through system-environment interplay. By focusing on exchanges and interrelationships, the system demonstrates potential to evolve via environmental interaction. This is achieved through the conservation and management of appropriate resources provided by each entity, so exhibiting proof of concept. 3 Dedicated to my inspirational late father (my alpha and my omega). To my family - my loving husband and my beautiful and patient children- my collective raison d’être: my gorgeous little ballerinas Georgina and Jemima and to my sweet baby William - who has been subjected to visiting the libraries and special collections; sitting on my knee, from a newborn to a toddler whilst we wrote almost every iota, in ‘virtual’ isolation - together! (The hand that rocks the cradle...?). Also, lest she is forgotten… for Emily Wilding Davison Facta, Non Verba 4 Acknowledgements I must thank my supervisory team: Professor Azzelarabe Taleb- Bendiab, my Director of Studies Mr. Andy Laws and my Third Supervisor, Dr. Denis Reilly. I also thank Dr. Stu Wade (retired Supervisor) for his noteworthy prior contribution to the research and am grateful to Dr. David Llewellyn-Jones for his advisory role. Additional thanks to Dr. Mark Taylor and Mr. Mark Allen. Similarly to Dr. Paul Strickland and Dr.Carl Bamford (the latter my project supervisor) - two gentlemen, in the very true sense of the word, who assisted me greatly with my first degree. Many thanks to the technical staff from within the School of Computing and Mathematical Sciences. Their timely, professional, responses enabled me to undertake my PhD often under extreme conditions. I especially thank Mr. Paul Cartwright and his seemingly endless technical knowledge and likewise Mr. Warren Anacoura, Mr. Steve Thompson, Mrs. Trina Fitzpatrick, Mr. Dave Folksman and Mr. Neil Rowe. Appreciations to three ladies within the School Office, who have shown consideration, assistance, and professionalism: Miss Janette Skentelbery, Mrs. Loretta Gomm and particularly Miss Lucy Tweedle. Many thanks also to Miss Emily Burningham of the LJMU Special Collections and Archives for both her helpful and timely assistance with viewings, often at very short notice and again allowing William to be in-tow. Immeasurable thanks to my loyal and true friends who have supported me over many years, particularly my children‘s modest Godmothers. To my respective English & Latin teachers at St. Hilda‘s High School for Girls - Non Nobis Domine! 5 To the recently deceased Meir (Manny) Lehman; uninterested in celebrity, yet passionate for his cause célèbre – the advancement of software evolution, via his extensive and groundbreaking magnum opi. The canonical principles underscoring Lehmans‘ research corpus have been an irrefutable motivation to this study; Age can no longer wither him, nor comfort mar his infinite variety. To my loving and eloquently principled late father, who gave me his all by imparting just values, a strong work ethic and sepia-tinged memories of a Blytonesque childhood - so inspiring a lifelong love of reading and writing. Finally to my ever precious babies „How do I love thee…?‟ Georgina, Jemima & William – I did this because of you and for you, with all my love ad infinitum, from Mummy XXXX 6 Contents INTRODUCTION........................................................................................................... 11 1.1 MOTIVATION ...................................................................................................... 13 1.2 STATEMENT OF THE PROBLEM ........................................................................... 15 1.3 AIMS AND OBJECTIVES ...................................................................................... 16 1.4 RESEARCH CONTRIBUTIONS ............................................................................... 18 1.5 SCOPE OF THE THESIS ........................................................................................ 21 1.6 THESIS STRUCTURE ............................................................................................ 22 BACKGROUND ............................................................................................................. 24 2.1 IBM AND AUTONOMIC COMPUTING .................................................................. 24 2.2 CYBERNETIC DEVELOPMENT ............................................................................ 28 2.3 CYBERNETICS VIS-À-VIS AUTONOMIC COMPUTING ........................................ 41 2.4 CHAPTER SUMMARY ........................................................................................ 44 LITERATURE REVIEW QUA VSM & RELATED MODELS ................................ 45 3.1 FEEDBACK CONTROL IN THE SOFTWARE PROCESS ............................................. 45 3.2 THE VIABLE SYSTEM MODEL ............................................................................ 50 3.2.1 Environment .............................................................................................. 61 3.2.2 System One (S1).. ...................................................................................... 63 3.2.3 System Two (S2) ....................................................................................... 66 3.2.4 System Three (S3) ..................................................................................... 67 3.2.5 System Three Star (S3*) ............................................................................ 69 3.2.6 System Four (S4) ....................................................................................... 70 3.2.7 System Five (S5) ....................................................................................... 72 3.2.8 System Three- Four-Five Metasystem Homeostat (S3-4-5) ....................... 74 3.2.9 System Three-Two-One Metasystem Homeostat (S3-2-1) ......................... 74 3.2.10 System Four-Five Metasystem Homeostat (S4-5) ...................................... 75 3.2.11 Models……………………………………………………………… …...75 3.2.12 Communication Channels…………………………………………… ….76 3.2.13 Viability…………………………………………………………… ……77 3.2.14 Recursion ................................................................................................. 78 3.2.15 Managerial Cybernetics .......................................................................... 79 3.2.16 Variety and Variety Engineering ............................................................ 79 3.2.17 Homeostasis ............................................................................................. 82 3.2.18 Autopoiesis .............................................................................................. 83 3.2.19 Amplification ........................................................................................... 84 3.2.20 Transduction…………………………………………………………… . 85 3.3 BRATMAN ET AL‘S INTELLIGENT RESOURCE-BOUNDED MACHINE ARCHITECTURE (IRMA) ......................................................................................................................... 87 3.4 J-REFERENCE MODEL ………………………………… ................................... 89 3.4.1 IRMA Architecture
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