One of the interesting divisions of opinion at the
SPARK workshop (and surfacing afterwards in the
blogs of some of the participants) was about something we might call the weight of the enterprise.
Dare Obasanjo asserts
My Website is Bigger Than Your Enterprise. And Jeff Schneider retorts
My Enterprise Makes Your Silly Product Look Like A Grain of Sand. So who is right?
The basic issue here seems to be the relative amounts of complex engineering required to produce enterprise-grade software versus web-grade software. Dare (and some other participants at the SPARK workshop, including the guys from mySpace) are producing web software with staggering user volumes - much greater than most enterprises have to deal with.
Dare is scornful of enterprise architects, who (he says) "tend to seek complex solutions to relatively simple problems". He and
David Heinemeier Hansson are particularly rude about
James McGovern.
But as Jeff points out, "most people who have never seen a large enterprise architecture have no concept of what it is". CIOs and enterprise architects generally regard enterprise software (their own realm) as much more challenging than web software, involving much higher levels of complexity, and much stricter "non-functional" requirements (security, robustness, and so on). Are they right, or is this just narrow self-interest?
Size, complexity, weight - these are basic architectural concepts. Part of the difficulty with this debate is that we simply don't have an agreed language for discussing architecture properly. In my opinon, IT education is very deficient in this area. (See Footnote 1.)
Enterprise Mashup
One way of thinking about enterprise mashups is that they provide a way of achieving enterprise-grade systems without enterprise-heavy engineering. Let me give an example of something I regard as a business mashup. My example doesn't involve Ruby, it doesn't involve web services, and many people might say it doesn't even count as SOA. But it has always been my favourite example of the "plug-and-play" business that I describe in my book on the Component-Based Business.
Tesco Personal Finance (TPF) is an example of what I would now regard as a business mashup. It combines (mashes together) banking services (provided by the Royal Bank of Scotland) with retail services (provided by Tesco).
From Tesco's perspective, this mashup provides an extremely lightweight way of entering the banking business. In the old days, if you wanted to open a bank, you had to collect a large amount of gold, which you had to deposit with the banking regulators to satisfy them of your financial stability. Then you had to open a number of branches, and employ a small army of clerks and managers. This represented a considerable investment and risk - which meant that the existing banks could earn high profits behind high entry barriers.
In contrast, TPF represented for Tesco a low-cost, low-risk way of entering the banking industry. Simply plug in some external banking services (which already satisfy all the necessary banking regulations), and a humble retailer can become a bank overnight.
SOA
Although the Tesco Personal Finance initiative predated the SOA and Web 2.0 technologies we have today, we can now interpret it as a precursor or harbinger of these technologies - almost a non-technical proof-of-concept. (See Footnote 2.)
SOA enables the lightweight enterprise. It does this not through services but through architecture. (That, in my view, was the primary justification of SPARK.)
The challenge of architecture is to
deconflict the enterprise software space - to create a genuine
separation of concerns. This is easier said than done, and it requires some complex architectural thinking. One of the products of this thinking may be platforms on which developers may use small-scale and simple development techniques to produce large-scale and complex solutions.
See my recent posts on the Business Stack (
SPARK Workshop 2) and
Enterprise Mashups and Situated Software.
Footnote 1 - I have always been critical of university IT courses that teach students to write small programs, and fail to teach them the differences between small stand-alone programs and large interconnected suites of programs. If you go to architecture school, you may never build anything larger than a garden shed with your own hands. But you will have looked at skyscrapers and understood the relevant design and construction principles. You won't qualify as an architect without understanding the scale differences between garden sheds and skyscrapers. But in IT there is no such educational requirement. Vast numbers of people get university degrees in IT-related subjects, and even fancy job titles including the word "architect", without having a clue about effects of scale on software.
Footnote 2 - Sometimes technology seems to make new things possible. But we often find that these things were possible all along, they were just too difficult or expensive or risky. In the 1950s, Stockhausen was producing music that predated the modern synthesizer - and it took him months to produce music that later composers would produce with a few quick knob-twiddles. Some might argue that Stockhausen's achievement was all the greater because of his lack of tools. Similarly, many Renaissance painters might have been able to produce their pictures more efficiently if they had had digital cameras. But perhaps their paintings (and their artistic innovations) were all the greater for being done without modern technology. See my post on Art and the Enterprise.
