On Apr 05, Jon MacLaren loaded a tape reading: ...
What kind of obligations can you have on the initiator side if "the obligations in the agreement are not dependent on the initiator being informed of the decision"?
I can't reconcile these two ideas.
Jon.
The point is that there is a momentary hazard where the initiator is _possibly_ obligated and does not know whether the Agreement will happen or not. If he is obligated to pay for service, he doesn't know whether he will need to present funds at some point... he might not want to spend them elsewhere, etc. In many cases, this hazard can be dealt with speculatively: by waiting for the answer. Waiting is not a satisfactory speculative behavior if and only if the Agreement terms include real-time scheduling constraints at the same temporal granularity as the messaging, e.g. if waiting causes a violation. This is a theoretical corner case, and may not be a practical one if entities are conservative about the kinds of agreements they will negotiate, e.g. not trying to negotiate about services with hard start times that are "too close" to the present. Another solution might be to deploy WS-Agreement in an environment with better messaging guarantees. If messaging itself were trustworthy, it might make sense for there to be introspective terms in the Agreement that bound the responder's decision time (for example, the responder is in violation if he says "yes" too late). For many best effort cases, the waiting solution can mask this hazard since delay is not a violation for either party. I really don't know where to go with this discussion. I've been making this point for years too... A phased approach cannot resolve this hazard: someone is always the last to know, and the other party doesn't know if he knows. Pure transactions do not work in this kind of quasi-realtime problem where they cannot be rolled back, i.e. work cannot be undone and resources cannot be unspent. Other compensation actions must be undertaken, e.g. pay a penalty, to offset the costs of the system thrashing and not doing real work. karl -- Karl Czajkowski karlcz@univa.com