ISO is the International Organization for Standardization. Since 1947, as the world’s largest developer of voluntary International Standards, they have published more than 19,500 standards!
TOGAF embraces but does not strictly adhere to ISO/IEC 42010:2007 terminology
The one I want to talk about here is formally known as ISO/IEC/IEEE 42010:2011 (such a catchy and memorable reference!). This is a standard for describing architectures. The idea started in the 1990s as a simple meta model with definitions. It was taken up by IEEE (pronounced “Eye-triple-E,” and standing for the Institute of Electrical and Electronics Engineers), and in 2000 they published IEEE 1471 – the first standard for architecture description. This was then adopted without change, and published by the International Standards Organization as ISO/IEC 42010:2007.
Wow! The reason I mention all this is that, rather confusingly, this standard is referred to as both IEEE 1471, or ISO 42010. And many people refer to the 2007 version even though it has been updated! The most recent version of this standard however is ISO/IEC/IEEE 42010:2011. The best reference point for keeping up-to-date is the home page for this standard on the ISO website. This also has a useful set of Frequently Asked Questions, practical examples of its application in different contexts, diagrams that explain the conceptual model, and definitions of terminology.
So what has all this got to do with TOGAF? According to the TOGAF documentation “TOGAF embraces but does not strictly adhere to ISO/IEC 42010:2007 terminology”. Now you may have noticed this quote refers to the now updated 2007 version… but let’s not worry about that too much. Here are a couple of key points:
- In the ISO standard “system” is a key term, but it is used as a placeholder. The standard doesn’t answer the question “what is a system?”. One possible option is that system refers to an enterprise. TOGAF explicitly considers the enterprise as a system. Following this, the ISO context diagram provides a good succinct summary, showing that an Enterprise (System) exhibits an Architecture, which is expressed in an Architecture Description:
The second point is that broadly the language of TOGAF conforms to the definitions in the ISO standard. ISO defines some of the fundamental terms – such as architecting, architecture, architecture description, architecture framework, architecture viewpoint and architecture view, concern and stakeholder – that lie at the heart of TOGAF.
- The ISO website includes useful MS Word templates for architecture description and viewpoints. Hint: you can find them if you click on Applications, and then look for “Templates for using the Standard”.
- Finally, the standard defines the minimum requirements for an architecture framework. And TOGAF, of course, is an architecture framework. The idea is that future and existing frameworks can orient themselves around these requirements to improve understanding and interoperability for architects working in various frameworks – which can’t be a bad thing!
If you aren’t familiar with the ISO standard then it’s well worth taking a look at the web site. It’s well presented and has very useful diagrams, templates and examples.
And if your enterprise is still using IEEE 1471 or the earlier versions of the ISO standard, then it’s time to get up-dated! ISO/IEC/IEEE 42010:2011 is a valuable resource for all types of architect, whether you are working on systems and software engineering, or the enterprise or business levels.