Both John and Anders feel that certain key artefacts have been placed at the wrong layer of abstraction. John writes
"In my view, Business Rules should not be located at the strategic level at all. I would argue that Business Rules primarily “belongs” to the Business sub-architecture domain."
What is the basis for this argument? Anders points out a consequence
"business rules are located in the government strategy layer and thus tightly coupled to the long term vision of the government agency"
"Business rules are operationalisations of the long term strategy and strategic intent.
Whilst the vision, mission, and purpose of the enterprise do not change very often (i.e. provide the best available services our citizens), the business rules and processes involved in realising this will definitely change."
and therefore
"Business rules belong in the business architecture."
Thus Anders is basing his argument on a statement about the frequency of certain classes of change.
This statement appears to be empirically testable, although I know from my own experience that it is a lot difficult than one might think to gather data to test this kind of statement.
Part of the problem of measuring rates of change is that we don't have a particularly robust theory of change in the first place. Let's look at an example. From time to time, perhaps every year, Steve Ballmer restates the vision of Microsoft. Obviously he doesn't use exactly the same words every year. And of course Microsoft-watchers will seek to interpret even the slightest change of wording or emphasis as a sign of a strategic change in direction. So even if Ballmer himself insists that the vision hasn't changed, we might not believe him. Looking back in time, we might find that major changes in direction had already been hinted at in previous years. So at what point does an apparently minor change in wording become a substantially new vision?
Conversely, when a company has been exposed as unethical, the CEO will go public with an apology and an assertion of a new ethical vision. (Recent example: Barclays Bank.) We might not believe him either.
In both cases, we will probably judge whether there is a new vision or not by observing whether the company behaviour and rules changes or not. (And this is not just external observers - Microsoft and Barclays employees and managers are also making these judgements.) So the rate of change of vision might be epistemologically indistinguishable from the rate of change of behaviour.
However, despite the difficulties in conceptualizing and measuring change, I think it does make sense to derive architectural layers from the idea that certain things have a characteristic rate of change, and that things with a different rate of change should be in different layers. This means that there is at least a possibility of subjecting an architecture to empirical evaluation. I have published this idea in articles for the CBDI Forum, and suggested that architectural theory needs to be based on the Pace Layering principle
In contrast, Anders' appeal to the IAF seems to be purely an argument from authority. The IAF establishes some "fundamental" categories, and so any framework that deviates from these categories must be wrong. I think this line of argumentation is weaker. Even though you may assert some attractive consequences of following IAF, I cannot see any reason for believing that these consequences follow only from IAF and not from any rival framework.
Frameworks and categories may be embedded in metamodels. But how do we know what is the basis for choosing between alternative metamodels?
John Gøtze, Metamodels (January 2013)
Anders Ø. Jensen, Enterprise Architecture and abstraction layers (February 2013)
Ethics, Barclays and totalitarianism (Catholic Commentary January 2013)
Barclays boss tells staff 'sign up to ethics or leave' (BBC News January 2013)
Did Barclays suffer an Ethics Meltdown? (CSR Zone, July 2012)
Sure Kamhunga, Barclays to re-examine its core values (October 2012)
Naven Johal, Barclay’s Does Something Right! (January 2013)
Updated 29 April 2013
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