Enterprise Architecture Analysis

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title

Enterprise Architecture Analysis

author

Bernard Szlachta (bs@NobleProg.co.uk)

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Enterprise Architecture Analysis。

• We create models in order to support the decision-making process
• Changes in the enterprise architecture should be consulted with the model
• Alternative designs should be

Analysis Techniques。

• What to analyse?
  • Functional
  • Quantitative
• How to analyse?
  • Simulation
  • Analytical

Functional Analysis。

• Validates weather the architecture works
• Validates architecture after change (is it going to work?)
• What is the impact of the change in terms of functional correctness

Quantitative Analysis。

• Answers quantitative questions questions like:
  • "how quick the response will come"
  • "how cheap it will be to make a change"
  • "how much is it going to cost"
• Performance is a major concern with today realities

Simulation 。

• Shows dynamic behaviour of the model
• Can check both Functional as well as non-functional aspects of the architecture e.g.
  • Is the message going to be received by an appropriate system?
  • How many messages can we send per second with the current setup?

Analytical Analysis。

• Provides non-statistical answers (i.e. result is reproducible)

Model Value Destruction。

by David Bridgeland and Ron Zahavi, Business Modeling: A Practical Guide to Realizing Business Value

• Not every model should be built.
• Sometimes the costs of creating and using a model are greater than the benefits that are gained from its use (model value destruction).
• Creating/using a model always takes time:
  • time interacting with the subject matter experts,
  • time spent constructing the model with modeling tools, and making the model simpler
  • time spent finding and fixing problems with the model,
  • and time spent verifying a model with subject matter experts.
  • time spent analyzing the model for business implications,
  • time spent explaining the model to others,
  • time spent maintaining the model when things change, and so on.

The decision about whether to create a model is ultimately an economic decision: Are we going to deliver more value using this model than we will spend creating/using/maintaining it?

Model Value Analysis。

• For small models, that can be built in an hour or four, we typically make a quick informal analysis (Do we expect to realize enough benefits to offset the time and trouble of creating the model?)
• Simple and useful model has value.
• More formal analysis - model value analysis - a summary of the expected costs and the expected benefits, and a comparison of the two.

• Spend 1% of the total anticipated modeling time on the model value analysis, to decide whether the other 99% makes economic sense.