View Architecture vs Architecture Description

Overview

This is, in Wikpedia terms, a diambiguation page - one that tries to differentiate between terms.

Architecture

Architecture is the property or concept of a real-life thing. You can be directly affected by it.

Architecture Description

This is a representation or a description of the real thing. It need look nothing like the real thing and can be a stylised product. Often it has it’s own notation or language as a convenient short-hand. You will be able to see it but you cannot be directly affected by it in the same way that you can be the architecture itself. It is a set of products - usually drawings, documents and so on.

See
• ISO 42010 definition of Architecture Description

Why Should I Care?

Are these the same? Does it matter?
cat.jpgpictureOfCat.jpg
They are not the same thing. Whilst you know that the second image is a representation of a cat it’s nothing like the cat itself - it won’t chase birds, it doesn’t ‘meow’ nor leave presents in the neighbour’s flower beds!

Architectural modelling or description is all about representing the real-life architecture. In definitions and when talking you need to be careful to distinguish between the two otherwise the reader or listener won’t know whether you’re talking about a problem or characteristic of the real-world architecture or your representation of it. This is particularly true in some of the management-like architecture views that describe the task and the model but make comment on the real-world architecture.

Equally if someone is talking about a “design pattern” for an “architecture” how do we know if they’re really talking about one for the real-world bits (often used by building architects) or one for the model (architecture description)? The latter one will be quite different and be affected by the framework and metamodel - the former very definitely won’t!

Some of the framework definitions are quite loose or woolly when referring to ‘architecture’. For example, the NAV-1 Overview and Summary Information Subview mixes the terms:

Purpose and viewpoint - Explains the need for the architecture, what it will demonstrate, the types of analyses (e.g., Activity-Based Costing) that will be applied to it, who is expected to perform the analyses, what decisions are expected to be made on the basis of an analysis, who is expected to make those decisions, and what actions are expected to result. The viewpoint from which the architecture is developed is identified (e.g., planner or decision maker).

Covered by NATO release conditions.

The ‘architecture’ doesn’t demonstrate anything - here it looks as though they mean ‘architecture description’. It is particularly important for this type of architecture view which can legitimately refer to both that the correct terms are used.

Similar problems affect the definition of MODAF AV-01 Overview & Summary Information View. It is also why the names of the TRAK MVp-01 Architecture Description Dictionary Viewpoint and TRAK MVp-02 Architecture Description Design Record Viewpoint were changed to include ’ Description’ to try and make the distinction clearer.

 

 

 

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