Session M200 - Managing Information the Right Way

SHARE 70
February 29 - March 4, 1988

John Zachman (IBM) has been involved for twenty years in systems analysis from an academic point-of-view. His comments here were interesting - we all would like to model the corporation accurately, build logical, physical and operational models for data, and be well documented; but we've got a JOB to do!

He mentioned something that we seasoned veterans have known for years, and the PC people are just finding out: "Decentralization without structure or architecture is chaos and anarchy".

Zachman contrasts building computer systems with house building. There are many different representations for your dream house: the basic layout you had in mind to begin with, the Architect's drawing, the Architect's plans, the Contractor's plans and his Shop plans, and the actual building itself. These are not so different from the logical descriptions of an application system, from the requirements as stated by the user through external specification, analysis, programming and delivery.

You can describe systems from many different viewpoints: he listed three.

  1. Functional specifications are like HIPO diagrams - you describe the Input, Process and Output. They are good for describing processes, but fall short when describing the information or objects being processed, or the final product.
  2. Material specifications are like Bill-Of-Material systems: they describe Objects, Relations and Things. They describe well how the pieces-parts all fit together, but don't give a hint as to how they got that way.
  3. Spatial specifications try to describe all the objects or information in relation to each other at any given instant of time: Site, Link and Site. The problem with this particular description is that it is a snapshot of a dynamic process.
The Zachman model of Information Systems Architecture is a matrix of different descriptions and models of the process being automated. He claims that when you describe a system you should produce Functional, Material and Spatial descriptions according to the views of all parties: the Business, the User, the Analyst, the Data Administrator, the Programmer and the System.

MY OPINION: this is the Chinese army approach to systems development. It is great if you have two hundred people, constant turnover, and your more immediate deadlines can wait. I keep thinking about the old joke: "up to {here} in alligators", it is difficult to remember that the "original objective was to drain the swamp".

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