Saturday, May 2, 2009

SOA : A Tale of Two Cities

This post is an attempt to illustrate a key message: the benefits of SOA are dwarfed by the inconvenient of not doing it. When I write SOA, I mean the combination of MDM (Master Data Management), EA (Enterprise Architecture) and Service Architecture on a global scale. This has been the topic of many of my posts, so I won't go into details. I won't detail the expected benefits either (cf. the previous post on SOA's presumed death) : cost reduction, increased agility, sharing and complexity reduction.

What is clear for everyone is that this approach has a cost. It can be a large set-up cost for a first project or a moderate "architectural investment" if SOA is a sustained practice. I have witnessed the two alternatives when a large-scale new project is launched: with and without such an effort.

It is now clear for me that the true difference in the outcome is not the set of expected benefits of a "disciplined/architected" approach, but rather the unexpected benefits (what one could call the strategic agility) and even more the avoidance of major problems in the future life of the IT system that is being built, mostly with respect to data integration.

Separating between strategic and tactical agility makes sense. Tactical agility may be defined as the ability to make the "easy transformations" to the information system (IS) as easily and cheaply as possible (they go hand in hand). Strategic agility is measured by the cost of making "the hard changes" (those that are deemed "impossible" the first time the need is mentioned). Easy vs. hard is both a matter of anticipation (strategic agility is the ability to move the IS towards a brand new direction) and scope. Most of the technology, such as middleware, is geared towards tactical agility. It helps to implement "reasonably easy changes" faster (sometimes much faster). But what helps to "turn around the ship a full 180 degrees" is the hard work on architecture (mostly, data architecture and then, service architecture). See the recently posted bibliography for more pointers. Strategic agility is difficult to evaluate, but not impossible. Playing with scenarios seems to be the best approach. See my book, or "Organisational Capital", edited by Ahmed Bounfour. For the lack of a better word, I will call structural agility the "status of being able to avoid major problems" through the taming of complexity. When complexity is not curved, unseen consequences start to happen. This is when we see huge overruns in budget and time, or even complete failure of large projects.

I am always worried when I see a "core-centric" project, usually motivated by the introduction of a new technology. A "sacred alliance" occurs between the client who sees the new technology as a quick relief of a precise pain, some itching that has been going on for a while, and the IT folks who are always happy to try on a new thing. New technology here may be a rule-based engine, a new database techno, some learning/recommendation engine, a new Web/Interface generation tool, etc. What I mean with "core-centric" is the focus on the core "new thing", the core "new benefit", as opposed to the edge: the integration with the rest, the way the new system interacts with the old stuff. Core-centric projects always follow a successful proof of concept. When the focus is on the core, it is actually hard to fail a proof of concept … I have, obviously, nothing against proofs of concepts. They are clearly necessary, there is no reason to work on the hard stuff (the edge) if the core benefits is not worth it. But one must keep in mind that a successful "proof of concept" is theeasy part. A common plague of core-centric projects is that they are often "designed by committees". This will be the topic of another post … an IT component need to have on clean business customer (a physical person) and one identified architect.

Core-centric projects tend to start well and to end in misery when adding the last 20% of data integration seems to cost 80% of the effort. The sad thing is that one cannot buy an enterprise architecture from an outside vendor (although help/consulting works J). A "turnkey" project, even with a high quality supplier, delivers exactly what you pay for, but no more. Precisely, the level of integration is what is defined in the specification. Extensibility, the ability to add a new data source, to take a new business practice into account, to adapt to a new competitor… are why architecture is necessary before adding a new IT component. One cannot expect to get this kind of "forward thinking" from an outside vendor. ISVs cannot, as a general rule (and each rule has its exception) carry the weight of the integration issue. Another way to say this is that integration should be "inward-bound" and not "outwards-bound": what matters most is outside the new project, not inside. This applies especially to SOA: it is much easier to define the services that a new component may expose than the services that it may use.

IT Strategic Alignment, a buzzword of these last 10 years is indeed a difficult exercise, because of the dynamics of the target – constantly moving - and the inertia of the IS. Enterprise Architecture is about system dynamics and trajectories. Aligning over the "strategy" is necessarily difficult because the target is vague and shifting its shape continuously. The fast movement of the target coupled with the slow speed of IT transformation means that both anticipation and abstraction are required. Anticipation is necessary because transforming the IS takes time. Even within the framework of a sustained SOA effort, herding the set of services towards the desired service architecture takes time. Abstraction is required to filter out the "micro-variations" and to focus on the key long-term changes.

Let us pick an analogy: imagine that we want to wrap objects of various shapes that are given to us randomly, with sheets of a rigid material. A good example would be statues, since they exhibit very different forms. To prepare beforehand, we pre-fold the sheets. Obviously, the objects represent the business opportunities … while folding the sheets represent undergoing IT projects to fit the opportunities. The preparation beforehand is similar to enterprise architecture: a little effort in advance to speed up things when the real problem occurs. However this preparation only helps if the folds are actually useful to wrap the new shapes. It is actually an interesting analogy since finding a set of versatile preparatory folds is a hard problem.

The following set of illustrations is taken from wrappings by Christo. They are not the best illustration of this fictitious example (no pre-folding since the wrapping material is not rigid) but they look nice J

From this analogy we can pick three key principles:

  • One cannot do the architecture without knowing what "the future holds" from a business perspective : Service Architecture is about business
  • Going from the shape to the folds is tricky : Architecture is not for "dummies", it requires thinking and abstraction
  • One can overdo it and spend more time solving the puzzle than solving the business problem. It is easier to wrap a complex form than find the optimal set of folds that would help wrapping the most.

It would be easy to transform this post into a fictional story to contrast two approaches for a new complex IS project, with and without a SOA investment. I might do this as a new "Caroline story" for a new edition of my book, in a Tale-of-two-cities' style. So, to return to the initial question, what could motivate Caroline to "do it right", if it means a slower start and an increase in the total cost ? Purely defensive arguments are hard to sell, even if perfectly correct (e.g., a higher cost estimate but a higher probability of avoiding overruns). This brings us back to the concept of "situation potential", borrowed from Chinese strategy and which I have mentioned earlier. This is truly a powerful idea, worth yet another post; it unties the Gordian knot that mixes complexity, the difficulty to forecast and the different time scales. It may be seen as the combination of tactic agility, strategic agility and structural agility. Being able to demonstrate and sell the increase of "situation potential" is what it takes to develop a long-term Enterprise Architecture effort.

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