Compare and contrast the persistence requirements associated with event systems and tuple spaces in the infrastructure of smart spaces.
What will be an ideal response?
Events are intended to be delivered immediately to consumers and, by default, they do not persist. A smart space implementation could, however, choose to record all the events that occur for debugging or replaying applications -- in which case a separate event store would be required, which subscribes to and consumes all events.
Tuples in tuple spaces have lifetimes that are independent of the lifetimes of the components that place them them there. That is a benefite in itself, given changes in the set of participating components. However, it could turn out to be a problem, since some tuples might never be taken from the tuple space even though they have no further value. For that reason, a tuple space implementation might delete tuples after a suitable period of time.
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