If you haven't, you should read this first.
Jeff, your heart really seems in the right place. Really. I tend to agree with you, though it may not have been obvious from my posts, that we need to elaborate on underlying principles of service orientation. I don't think that the four tenets are in any way perfect. In fact, in hat tip to your redundancy statement, I would probably claim that 'services share schema and contract, not class" is practically a corollary to the "boundaries are explicit," especially if you use this dictionary definition of explicit:
I think my basic points are that the four tenets add value at a certain level of abstraction, and that we need to refine from there. I will have to be brief [last minute shopping beckons],
But:
Bible reference: Is that your "New Schneider Version?" :) Dude, you should look into a good seminary course -- your exegesis could use some help. The first statement stands on its own merit in the original hebrew. Some of the fault lies in our overloaded use of the word 'love' in English. Your point is, none-the-less, taken.
No, you didn't clarify the difference between philosophy and constraints, though you gave some reasonable examples of constraints, and I get it.
You are wrong on the constraint you derived from "Boundaries are Explicit." That isn't what it is saying at all. Nope. No sir. What you are talking about are implementation details at this [I hestitate to say] level of abstraction.
The second part of boundaries are explicit is really, in my mind, more about the "not classes" part of the "schemas and contracts" tenet later. The redundancy shows.
I don't know that I buy your versioning constraint under autonomy. That is a should, not a must. We should be aware of the consequences, but services are going to get versioned out of existence.
Schema and contract doesn't necessarily (in my mind, at least) mean XML Schema, though we are basically stuck with it for now. This could instead be a guiding principle for where schemas need to go to be able to adequately describe services. I don't have much more on that either, though.
I haven't made it all of the way through the MS video yet, but they don't seem to butcher it too much. The point I am trying to make is that you shouldn't be berate the butcher when your over there carving the pig up. :)
Now, that being said, I will try to provide more constructive feedback, following your lead. Just after the shopping and such. In the meantime, I will point you all back to Pat Helland's excellent section on messages from his article on data inside and out, which I think is a wonderful start in the right direction. Scroll down to Table 1 for the brief version.
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