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Architecting in a Complex System Environment. John Hodgson & Phil Piper ICT Architects April 2013. 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).
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Architecting in a Complex System Environment John Hodgson & Phil PiperICT Architects April 2013
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. • 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 often 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 is preferred to 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 • Solution v’s System v’s Enterprise Architects
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 must be multi-disciplinary • I.T. Architects become valued as complexity increases
Complex Systems are influenced by many factors Examples New Defence Warehouses Expanding Mobile Environment New Services structures Aging Application infrastructures Changing Business Models Changing partner requirements Increasing efficiency demands
Architecture Frameworks • Framework v’s Architectural process • TOGAF (I.T.methodology) • ZACHMAN (ZF) • DODAF, MODAF and AUSTDAF (Defence-focus) • http://www.iso-architecture.org/ieee-1471/afs/frameworks-table.html • “Common languages” for architects • Rarely exactly accurate • Some are primarily processes, rather than a framework • Most frameworks have a logical flow (process) to them • 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 • MS SharePoint folders • 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 TV Science Show) • Always ask - WHY is it so?”
Time for Questions And thanks for listening…