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Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013
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Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

Mar 31, 2015

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Page 1: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

Architecting in a Complex System Environment

John Hodgson & Phil PiperICT ArchitectsApril 2013

Page 2: 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).

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.

Page 3: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

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

Page 4: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

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.

Page 5: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

Dept of Defence

Page 6: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

Dept of Defence(same information)

Page 7: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

Defence – ERP Interfaces

Page 8: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

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.

Page 9: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.
Page 10: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

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

Page 11: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

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

Page 12: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

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

Page 13: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

JSF – A study in complexity

Page 14: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

JSF – Understanding how your element fits in

Page 15: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

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

Page 16: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

Zachman (Circa 1990)

Page 17: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

TOGAF(Open Systems Group)

Page 18: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

DODAF V2

Page 19: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

MODAF

Page 20: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

AUSDAF

Page 21: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

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

Page 22: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

External Imposed Policies & Controls

Page 23: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

Technical and Threat Risk Assessment

Assessment Processes Risk Sources

Page 24: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

•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.)

Risk Calculation Form Risk ID: R01

Threat Loss of services due to loss of communications (Example Only)

Threat sources TS16, TS17, TS19, TS20, TS21

Asset(s) Affected A1, A2, A6 A9, A30

Overview (insert comments here)The loss of the (System/Project Name) services due the infrastructure and networking outside the control of Defence being damaged or wrongly configured.

Likelihood of Occurrence (insert historical supporting information here)Possible

Consequence of Realisation (insert any supporting consequential comments here)Severe

Current Resultant Risk Exposure (insert further specific comments here)High

Treatment Option(Accept, Reduce, Avoid, Share)

Reduce

Treatment Recommendation(s) / Plan(s) TP01, TP02

New Likelihood of Occurrence (insert supporting future outlook comments here)Very Rare

New Consequence of Realisation (insert comments that may support the lowering of consequence, if justified)Severe

New Resultant Risk Exposure (insert any comments here such as countermeasure accompanied by treatment plan allowing the previous rating to be lowered)Medium

Table R01 – Loss of services due to loss of communications

Threat / Technical Risk Assessments (Aust / ISO Standards)

Page 25: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

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?”

Page 26: Architecting in a Complex System Environment John Hodgson & Phil Piper ICT Architects April 2013.

Time for Questions

And thanks for listening…