Steve Maine, as usual, has as very thoughtful summary of the core specifications of the Web Services Architecture as presented by Don Box in his talk, WS-Why?, at the XML Developer's Conference. What, according to Don Box, are the core specifications?
- XML: Common data model and way of looking at the word
- SOAP: Orthogonal content and extensibility
- WS-Addressing: Transport-agnostic view of a message's destination and source
- WS-MetadataExchange: Self-Description
- XSD/WSDL: Contract description languages
If any of these specifications are not already well-known to you be sure to peruse Microsoft's introduction to the Web Services Architecture witepaper.
A recent C|Net News article features a Paris Cost/Benefit statement about “pulling a Munich”, i.e., mandating a complete change-over to “open source” technologies. The Paris report's conclusion?
“...it would mean significant additional costs without improving the service provided.”
A French daily is quoted saying that it would cost $70 million USD over 5 years to move away from Microsoft to open source technologies. The largest portion of that, $12 million USD, for retraining.
The statement concludes that Paris will be
“...moving away from dependence on the information technology of providers with de facto monopolies.”
But the question is: are you trading one lock-in for another? For example, J2EE is a quasi-open standard. But as web sites building tools become more powerful (read: complex) it will be harder and harder to code to an agnostic standard. An old develop saw goes: “If it isn't tested, it doesn't work.” I feel it will certainly become the case that unless you are diligently committed to “open-standards” and rigorous regression-test on two or more platforms, it will become very difficult to not get sucked into lock-in.
At which point you have to ask yourself: Do I was to be locked-in to the “de facto monopoly” or to a barely-supported marginal player or unsupported open-source player?
Hmmm, I think I'll stick with the monopolist. Something to think about...