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Participants

Today it was the turn of participants to get a hammering.

A SOA is all about people; about people getting things done. What is more, people have all kinds of relationships to each other :-). What, you might ask, has that got to do with SOA? A lot in my opinion.

Here is an example. Suppose that someone wants to set up a system that allows, among other things, groups, teams, and societies (such as the Society for the Preservation of Cats in the San Francisco neighborhood) to be formed and policed. There are many situations where that is already happening, just take a look at MySpace. Well, each society is going to want its own rules for governing itself. Of course, there is always an overarching set of rules that we abide by: the state and federal law; but federal law tries not to interfere too much in the way that the SPCSF is run.

Our SOA that is supporting all these societies might allow people to execute actions via the SOA: such as declaring that someone is the president, a meeting quorate and so on.

What is a service to do when it receives a request to promote a society member the new president of that society? Certainly, we could restrict the system to record keeping, but a deeper system will try to ensure that the promotion is valid. That involves knowing if the promotion action is from a valid source, whether the action is properly enacted and so on.

All of these validations, and the consequences that follow from the action (the new president can call meetings to order) are really about these other 'out of band' relationships between participants in the SOA system.

The same is really also true for ordinary commerce: a minor may not legally enter a contract (and therefore may not legally buy anything over the Internet). Such a fact is currently respected in the breach more than the observance; but I expect that things like SOX will change that for a lot of people. Enterprises are a lot more like mini-societies than most IT staff (and C*Os) give credit for.

We are trying to ensure that our Reference Architecture properly accounts for the possibility of these out of band relationship because they affect the performance of the system itself. Of course, it is not our job to define what the rules are; only how any set of rules might integrate with SOA-style systems.
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