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Explore the fundamentals of complex IT systems using government examples. Learn about architecture frameworks, useful approaches to understanding complex systems, and the influence of factors in a complex environment. Discover the tools essential for a complex system architect and effective strategies for architecting in such environments.
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Architecting in a Complex System Environment John Hodgson & Phil PiperICT Architects
The fundamentals of Complex IT System/s(Using Government systems examples) • Complex IT systems • What is a complex IT system? • Common Factors and Influences (within a Government environment). • A Systems of Systems view • Common Factors • Value and issues in identifying, analysing, designing and specifying IT systems in a complex environment. • Architecture Frameworks • Models and Zachman, DODAF, MODAF, AUSDAF and TOGAF Gordian knot. • Business, Systems, Services and Technology • Complex System Architect’s basic tool sets • Whiteboards, A3 sheets, Office, Visio, JPGs, System Architect, etc. • Useful approaches to understanding Complex Systems. • Useful approaches to Architecting Systems in a complex environment.
Complex I.T. systems • What is a complex IT system? • More than three subsystems.. • Multiple business process engagement • Significant data exchanges • Significant human interactions within the systems • How do you recognise this? • Different governance regimes evident • High frequency of change • Multiple data exchange methods • Complexity behaviours
An Alternate View of Complexity • What is a complex IT system? • A complex system is one that exhibits emergent behaviour. • Emergent Behaviour is behaviour that was not predicted from the sum of the functions of the parts. • For example, the World Wide Web is a “small-world network”. Ie, the number of hops between two nodes increases in proportion to the log of the number of nodes. That was not “designed-in” or predicted by the designers. • Emergent behaviour is often negative. We call this “bugs”. • So, system collections are complex when they start exhibiting bugs that are the result of interactions between the systems. These can be very difficult to diagnose.
Interfaces – How Many Are There? 2N > N(N-1) How can that be? For N systems, the worst case is N(N-1) What we would like is at most, 2N We can evolve a complex set of systems towards 2N by applying enterprise architecture patterns like SOA.
Systems of Systems • Complex systems are typically system of systems • Multiple layers of systems • Architects are often tasked with only a subset of this – Focus
Common Factors • Teaming is a necessity • No single source of truth • Fragmentation of design, projects and support • Documentation is always poor • Abstraction is essential • Architects become valued as complexity increases
Complex Systems are influenced by many factors e.g. Defence Warehouse Mobile Environment
Architecture Frameworks • Framework v’s Architectural process • TOGAF • ZACHMAN • DODAF, MODAF and AUSTDAF • “Common language” for architects • Rarely exactly accurate • Most can be correlate to each other
Basic tool sets for complex system architect’s • Whiteboarding • Print copies, photos, coloured pens • Integrated project teams, working groups, team reviews • A3 sketch pads • MS Office, Adobe Acrobat • Visio and JPGs • System Architect & Enterprise Architect • Above all, an inquisitive mind and some affront to ask questions
Technical and Threat Risk Assessment Assessment Processes Risk Sources
Threat / Technical Risk Assessments (Aust / ISO Standards) • Detailed Identified Risk Calculations • (Add/Remove Information where required along with Risk Forms. Comments can be made in any field to enhance or better explain the rating.) Table R01 – Loss of services due to loss of communications
Useful approaches to understanding Complex Systems • Start at the top - the Enterprise’s Business Objectives • Document visually and ask for comments • Identify the Executive’s direction of change • Document (or find) the objectives • Identify the Enterprise “modus operandi” • Develop (or find) an outline Concept of Operations (or Concept of Business) • How should the business be working? • How is it actually working? • Strategic, Tactical and Immediate objectives • Lean from those who have gone before • Look for historic and previous efforts • Ask for the war stories, but don’t accept as gospel • Where have the greatest changes occurred so far in the Enterprise? Why? • Look for “change levers” • Small investments - large impacts • Be patient • Enterprises take time to change • Both human and external factors rarely allow for “Engineering Discipline” • But it doesn’t hurt to bring some skills to bear. • Draw and Write for your audience • Who reads the Plumbing Specs for a new Building? • Prof Julius Somner-Miller (circa 1970s) • Always ask - WHY is it so?”
Time for Questions And thanks for listening…