EA as
Cybernetics
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Abstract
TOGAF says EA "regards the enterprise as a system, or system of systems."
A general system theory was developed in the1950s by Bertalanffy, Wiener, Ashby and others.
“An Introduction to Cybernetics”, by Ross Ashby, was published in 1956.
Ashby started “Cybernetics was defined by Wiener as "the science of control and communication, in the animal and the machine" in a word, as the art of steersmanship.
Co-ordination, regulation and control are its themes, for these were of the greatest biological and practical interest.”
Coordination, regulation and control are also themes of EA.
I have below paraphrased some sentences from Ashby’s book, replacing Cybernetics by EA.
And then added some comments presenting EA as a branch of Cybernetics.
(This is Cybernetics in its original form, before sociologists messed with it).
Co-ordination, regulation and control are themes of Cybernetics.
Coordination (integration), regulation and control are also themes of EA.
On the primacy of the behavioural view
EA is about the steersmanship of business entities and events.
It takes an essentially functional and behaviouristic view of a business.
On the standardisation and repetition of processes
EA deals with all forms of behaviour where the processes are regular, or determinate, or reproducible.
It is almost always about the plural rather than the singular, addressing classes of business entities and events that need to be monitored and directed.
On modelling continuous behaviour as discrete
EA treats the enterprise as a system in which all state changes are seen as discrete steps.
It assumes core business processes can “digitised”, that is, monitored or directed by digital information systems.
On modelling enterprise state in variables
EA treats the enterprise as a system whose current state can be represented as a large and complex vector, a compound of variables.
Trouble is, this vector is not only very large, but also distributed across scores or hundreds of business data stores.
And so, the enterprise architect has to study disintegrity between databases, and consider where and how to reduce it.
On systems as abstractions
We should be clear about what a "system” is.
Our first impulse is to point at an operational business and say "the system is that thing there".
This method has a fundamental disadvantage: every real-world entity contains no less than an infinity of variables.
A real computer has many attributes that must be ignored by enterprise architects.
A real employee has not only a name, salary and role, but also a nervous system, bodily organs, food tastes, musical aptitude, and so on.
Any suggestion that architects should study "all" the facts is unrealistic, and actually the attempt is never made.
What is necessary is that architects select and study facts that are both a) important to the success of the business b) systemisable.
The system now means, not a thing, but a list of variables that are useful and can be recorded.
The enterprise system is that which architects describe in an EA repository.
On change
EA is concerned with two completely different kinds of change:
· changes to an operational system state, the everyday behavior of the business, which occurs under its own business rules
· changes to a system description, change to business rules, described in “transition states” of an architecture description.
On the coupling of subsystems
EA is concerned both with the division of the enterprise system into subsystems, and with the coupling of those subsystems.
EA takes the holistic view; it looks to integrate subsystems to the benefit of the wider business system.
On the black box view of systems and subsystems
EA is concerned with abstraction of system description from operational system contents and workings.
Most obviously, it encapsulates systems and subsystems; it defines system behavior in the form of interfaces and service contracts.
On complexity
EA is concerned with systems that are not only large but complex, and challenges lie more in the complexity than the size.
On uncertainty about the system boundary
EA is concerned
with systems whose boundaries are determined by observers, and therefore
somewhat arbitrary.
But there is no escaping the need to bound the system of interest as best we can.
References
You can read relevant text from Ashby's original in the “Introduction to Cybernetics” paper on the System Theory page at avancier.website.
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