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Software Engineering Challenges: of Complex Self-Organising Systems Prof. A. Taleb-Bendiab School of Computing Liverpool John Moores University email: a.talebbendiab@livjm.ac.uk http://www.cms.livjm.ac.uk/taleb. Outline. Drivers for a paradigm shift Autonomic Grid Computing
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Software Engineering Challenges: of Complex Self-Organising SystemsProf. A. Taleb-BendiabSchool of ComputingLiverpool John Moores Universityemail: a.talebbendiab@livjm.ac.ukhttp://www.cms.livjm.ac.uk/taleb Prof. A. Taleb-Bendiab, talk: Reading’06, Date: 06/06/2014, Slide: 1
Outline • Drivers for a paradigm shift • Autonomic Grid Computing • Autonomic Computing • Setting the Scene for • Drivers for a paradigm shift • Quest for a new theoretical framework • Recent bio-inspired initiatives • SAS, DASADA, SRS and ANTS • Understanding autonomic systems engineering • Definitions and state of the art • Challenges and Open Research Questions • Complexity Networks • Self-organising systems • Complex random networks • Conclusions Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 2
Emerging Networked Landscapes Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 3
Drivers for a Paradigm Shift #2 • Modern Expectations • High-Availability -- 24x7 delivery • near-100% availability is becoming mandatory for e-commerce, enterprise apps, online services, ISPs • Change • Support rapid deployment of new hw/sw, services, etc • Maintainability • Provide flexible systems admin. env. • reduce system administrators tasks, complexity and cost • Just-in-time scalability • Allow flexible system up scaling without sacrificing performance, availability or maintainability • evolutionary growth and adaptation • Survivability • Full malleability Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 4
A Shift Towards What? • Key question is not only how to achieve the above listed modern expectations as: • a single metric/attribute or a cost/value-effective combination of them all • But IBM argues that it’s how to reduce the cost and complexity of achieving that • Management by delegation • Rethinking systems design • So where to next? Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 5
Autonomic Computing Inspired by the “autonomic” function of the human central nervous system. software systems that take care of the mundane elements of systems management themselves, allowing human operatives to concentrate on more important work. Major Recent Initiatives • 4 major research thrusts: • Biologically-inspired diversity: genetically diverse computing fabric • “Cognitive immunity” and self-healing: see automated cyber immune response and system regeneration. • Granular, scalable redundancy: This research thrust area will increase the practicality of redundancy techniques. • Reasoning about the insider threat to preempt insider attacks and detect system overrun. • A 2020 vision of a class of space exploration missions termed nanoswarms, where many cooperating picospacecraft or intelligent spacecraft work in teams to explore the asteroid belt, based on the efficiency and coordination of hive culture. • Some Recent Initiatives • SAS -- Self-Adaptive Systems (DARPA, 1997) • DASADA -- Dynamic Assembly for Systems’ Adaptability, Dependability, and Assurance (DARPA, 2000) • AC -- Autonomic Computing (IBM, 2001) • ACom- Autonomic Communication (EU, 2003) • SRS -- Self-Regenerative Systems (DARPA, 2003) • ANTS -- Autonomous Nano-Technology Swarm (NASA) • KP -- Knowledge Plane (MIT, DARPA, 2004) • Defined by Laddaga in the 1997 DARPA Broad Agency Announcement as: • “...software that evaluates its own performance and changes behaviour when the evaluation indicates that it is not accomplishing what the software is intended to do...”. • To adapt, the system reacts to environmental change - the problem is recognising the need for change, then planning, enacting and verifying the change - these are self-managing concerns Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 6
Autonomic Grid Computing at the Rescue • For more details • Autonomic Computing • Drivers for change • High-availability, etc. • Definitions • Designs and principles • State-of-the-art • Grid Computing • Middleware Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 7
Remaining Research Challenges • Host-Based • Complexity Paradox • Autonomic computing aims to reduce admin. costs, hide system complexity and intricacy, • Though, their designs are becoming more complex • as yet are poorly understood as echoed by D. Garlan 2005 • “… how do we design, build, and evolve such sw systems so that they can meet given—and evolving—requirements ...” • Incremental deployment of AC capabilities in legacy systems. • AOP-based evolution, Interoperation • Support functional and non-functional requirements for autonomy. • Evaluation mechanisms and metrics [ref] • Governance vs Autonomy Paradox • Balancing and adjusting governance and autonomy • Programming, control and Interaction Models • Complex-Based • Self-organisation • Complex and random Networks Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 8
Progress to Date #1 • Has been informed by a set of design paradigms • Model-based vs Self-Organising Systems design models • Top-down vs bottom-up • Applying and/or revisiting: • cybernetic principles • control systems theory, regulation, reward and sanctions • Decision theory, Complexity theory • DAI and CI • dynamic planning, deliberative models, ML • Middleware support • self-awareness, reflection and deliberation • Autonomic Software Architecture, etc. Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 9
The Story so Far #1 • Currently design models of the 1st generation ”autonomic systems” employ; • Explicit managed autonomy via policies and rule sets predefining at design-time all extraneous behaviour using constructs such as; • Event Condition Action, Design by contract • Separation of concerns – AOP, etc. • State-of-the-art of autonomic systems designs including; • autonomic software models and architecture, standards • tools and techniques to support • the design, modelling, analysis • and evolution of autonomic software • Define associated models for their • programming, control • interaction models with human and/or other non-AC systems (legacy). • Delegation of authority and its adjustment Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 10
Story so far #2 • More recent work is focusing on scalable methods for specifying dynamic behaviour of autonomic systems. • Axiomatic vs algebraic modelling • FOL based calculi Vs process algebra • Evolving • policies and control model • Structural/organisational model • Bounded autonomy and adjustments • Unifying models for • model-based and SOS approaches for autonomic systems engineering and management Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 11
Our Approaches #1 • More recent theoretical work is focusing on scalable methods for specifying and enacting dynamic behaviour of autonomic systems • Autonomic Systems Engineering • Related Work: IBMblueprint (www-03.ibm.com/autonomic/pdfs/ACBP2_2004-10-04.pdf) • An autonomic manager contains a continuous control loop that monitors activities and takes actions to adjust the system to meet business objectives • Autonomic managers learn from past experience to build action plans • Elements need to be instrumented consistently, based on open standards • Our model • Model-based Approach • Systems theory, design patterns, design grammar and service-oriented programming • A. Taleb-Bendiab, D.W. Bustard, R. Sterritt, A. Laws, M. Randles, F. Keenan, P. Miseldine, "Model-Based Self-Managing Systems Engineering", in Proceedings of the 16th International Workshop on Database and Expert Systems Applications (DEXA’05), SAACS'05: 3rd International Workshop on Self-Adaptable and Autonomic Computing Systems, pp., • David Bustard, Roy Sterritt, A. Taleb-Bendiab, A. Laws, M. Randles, F. Keenan, 05, "Towards a Systemic Approach to Autonomic Systems Engineering", EASE'2005. • David Bustard, Roy Sterritt, A. Taleb-Bendiab, A. Laws, M. 06, "Autonomic System Design Based on the Integrated Use of SSM and VSM", to appear in AI Review, Vol. , No. , Springer, ISSN 0269-2821. • K. Liu, A. Taleb-Bendiab, 05, "Presenting a Case for a Principled Approach to Citizen, Business and Technology Integration in e-Government Services: Challenges and Research Opportunities", Egov'05. Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 12
Our Approaches #2 • Emergence-based Approach • Complexity: Complex Systems • Seth Bullock and D. Cliff (HP Report, Ref.) • Complexity and Emerging Behaviour in IT Systems Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 13
Entropic Autonomic Design Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 14
Illustrative Example Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 15
Achievements So far … Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 16
Design Patterns: VSM and GOF Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 17
Related work Outlined in the Autonomic computing edge: The “Standard” way of autonomic computing, Brent Miller, 29/05/2005. Though more is required – Our Approach Autonomic Software Patterns Associated Frameworks Description languages Sensor and Actuator Description Service Assembly and deployment Monitoring Standards -- Interoperation Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 18
P2P Self-Organising Overlays: Grids Show Example -1 Request monitor (via MSDL) Readings Deploy Sensor (via SADL) Sensor Provider Show Example-4 Sensor & Actuator Framework Show Example-2 Readings as XML Inject Show Example-5 Show Example-3 Edit Sensors Select Sensors Consumer Sensors Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 19
Modelling Autonomy • Algebraic specification • Related work • Process Algebra • CSP • Static model checking and dynamic software analysis • Our model • Using SSC used to formalizes the behaviour of dynamically changing systems FOL (McCarthy, 1963).. • Support concurrent actions and timing constraints. • Each situation can be viewed as a history of previous actions. • Action, guards and time can be modelled at deliberation points in an autonomic setting. • M. Randles, A. Taleb-Bendiab, Philip Miseldine, Andy Laws, "Adjustable Deliberation of Self-Managing Systems", ECBS 2005: 449-456. [ppt] Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 20
Evolving and Adjustable Autonomy • Via compositional model and evolution of • Software services (components) • Software governance (Control) via • Formal modelling of norms, rules of play • Encoded via CA-SPA constructs • Enactment support – from spec. to code using Neptune language • deployed onto software control Centre (agent) on grid middleware • M. Randles, A. Taleb-Bendiab, P. Miseldine, 05, "Mind out of Programmable Matter: Exploring Unified Models of Emergent System Autonomy for Collective Self-Regenerative Systems", Extended Abstract, the 2nd GSFC/IEEE Workshop on Radical Agent Concepts (WRAC'05), NASA GSFC Visitor's Center, Greenbelt, MD, 20th-22nd September 2005. • Miseldine, P., Taleb-Bendiab A. “A Programmatic Approach to Applying Sympathetic and Parasympathetic Autonomic Systems to Software Design”, Self-Organisation and Autonomic Informatics (ISBN I-58603-577-0), Hans Czap, Rainer Unland, Cherif Branki, Huaglory Tianfield (Eds.), pp:3-17, IOS Press, Amsterdam, 2005.Awarded "Most Innovative Paper" at Conference • Miseldine, P., Taleb-Bendiab, A., “CA-SPA: Balancing the Crosscutting Concerns of Governance Autonomy in Trusted Software”, IEEE International Workshop on Trusted and Autonomic Computing Systems within AINA 2006. Vienna, Austria. April 2006. Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 21
Self-Governance Theory Deliberative layer using the EBDI model Formal modelling of norms, etiquette, rules of play deployed via CA-SPA constructs Enactment support – from spec. to code Governing Autonomy Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 22
Programming Autonomic Systems • Neptune Meta-Language • Integrated Development Environment: • Miseldine, P., Taleb-Bendiab A. A Programmatic Approach to Applying Sympathetic and Parasympathetic Autonomic Systems to Software Design. to appear in the 2005 International Conference on Self-Organization and Adaptation of Multi-agent and Grid Systems (SOAS’2005). Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 23
A Programming Model forSelf-Organising Object Systems Common Object Functionality Set Make Requests / Intervene in Operation Incoming Data Openness Data Formatter Monitor Status / Performance Common Feature Layer Evolvable Object Request Codec Processed Data Middleware Communication Register upon instantiation Mobility Distributed Shared Memory Facility Lookup a service Middleware Specify interest Serialize + Transport Inform of instantiated interest object Suspend Operation Prof. A. Taleb-Bendiab, talk: Reading’06, Date: 06/06/2014, Slide: 24
Object-Level Application Service Composition Performance Agent System Security Agent Middleware Service Gateway Object Inform Spawn Administrative Interface Common Feature Layer Middleware Direct Application 1. Register Request Service Spawn 7. Connect Service Gateway Prof. A. Taleb-Bendiab, talk: Reading’06, Date: 06/06/2014, Slide: 26
Example 1: A Grid-Based Decision Systems Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 27
Re-engineering via Neptune toolkit New Another One? -- Dental Triage Demo. Visual Modelling of Protocol or process flow Current System Process is compiled into an open introspective format New Grid-Based System Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 28
PCT/Other OH-Dental Service 24 Dental Triage Service Dental Inventory Service Dental Triage Service NHS Direct EPR Service E-Dental Booking Service Clinical Care Pathway/Governance Accounting/billing Service East Lancashire Architecture A&E/PDS/EDS/DPrac/Other East Lancashire Dental Middleware Adastra Call Buffer Service Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 29
Acknowledgements • Acknowledgements • My thanks to the Team • • Apologies to individual researchers • if I didn’t have time to mention your work • Useful Links • www.cms.livjm.ac.uk/2nrich • www.cms.livjm.ac.uk/cloud • www.cms.livjm.ac.uk/taleb Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 30
That’s the end – so I’m off ! Prof. A. Taleb-Bendiab, talk: Reading Guest Seminar, Date: 06/06/2014, Slide: 31