Category Archives: Thoughts on the World

Modelling an Enterprise Data Architecture

Unlike the simplistic models in books and training courses, a real enterprise has a very complicated data architecture. Most of the data will be held in large legacy or package systems, for which the details of data structure may be unknown. Other data will be held in spreadsheets and personal databases (such as
Microsoft Access), and may be invisible to the IT department or senior business data administrators. Some key data may reside in external systems maintained by service providers or business partners. To manage this you need powerful, simple, but effective models of the data structure from an enterprise viewpoint
— a set of models known as the “Enterprise Data Architecture.”

This article, co-written by Richard Wiggins and originally published in the Rational Edge in February 2003 describes a new approach, based on UML, which meets the real requirements of modelling the Enterprise Data Architecture.

Read the full article
Posted in Agile & Architecture, My Publications, Thoughts on the World | Tagged | Leave a comment

Combining Risk Factors

In “Waltzing with Bears” Tom DeMarco and Tim Lister introduce the very useful concept of the “Uncertainty Diagram”, the probability distribution for project metrics such as delivery date, expenditure or benefit delivery. This is used, for example, to assess the likelihood of delay from a given risk.

However, they rely entirely on Monte-Carlo simulation. I believe that where the curve is defined by, or can be approximated by, a few discrete points, a relatively simple analytical solution can then be used in place of simulation.

Read the full article
Posted in Agile & Architecture, Code & Development, Thoughts on the World | 3 Comments

Modelling Change in Enterprise IT

One of the big problems in a strategic or “enterprise architecture” view of IT is how to model the change in an enterprise’s IT portfolio over time. Most established modeling techniques deal with an essentially static view of the system landscape, supplemented by some modelling of the dynamics within systems. These are very poor tools if you are trying to understand how the complete set of systems, technologies and capabilities change over time. This item discusses two simple techniques which address this problem.

Read the full article
Posted in Agile & Architecture, Thoughts on the World | Tagged | Leave a comment

A Square Peg, and Only Round Holes

Musings on whether an architect can fit neatly anywhere in a traditional IT organisation hierarchy.

Read the full article
Posted in Agile & Architecture, Thoughts on the World | Leave a comment

The Changing Role of An IT Architect

An IT architect (for want of a generic term which isn’t already terribly overloaded) takes on many different roles over time. This article discusses some of those roles, and introduces a model for the different architectural interventions in a typical project life-cycle.

Read the full article
Posted in Agile & Architecture, Thoughts on the World | Tagged | Leave a comment

Characteristics of a Software Architect

My musings on what makes a good software architect.

Read the full article
Posted in Agile & Architecture, Thoughts on the World | Leave a comment

The Tao of the Architect

Philippe Kruchten of Rational has taken the Tao of Lao-Tsu, and created a modern translation focussed on the values and attitudes which an architect should adopt. He says many things which are also said on this site, but much more beautifully.

See http://www.bredemeyer.com/tao_by_Kruchten.htm
Posted in Agile & Architecture, Thoughts on the World | Leave a comment

Strategies for Flexibility

Organisations need to protect and maximise the value of their IT assets. To protect against threats from business and technological change systems need to be flexible: able to change to support new functions, new workloads and new working environments. Flexibility does not happen by accident – it is usually the result of planning, forward thinking and adopting strategies known to enhance and encourage it.

This paper (in Adobe Acrobat Format), originally published by the CBDi Forum, presents some of those strategies.

See https://www.andrewj.com/publications/Strategies%20for%20Flexibility%201d1.pdf
Posted in Agile & Architecture, My Publications, Thoughts on the World | Tagged | Leave a comment