xoEPC - Jan Mendling

72 3. Event-driven Process Chains (EPC)
wait context status in order to reproduce it at its output arc, see (d). XOR- and OR-joins
propagate a wait context if one of their input arcs has a wait context, see (e) and (f). Sim-
ilar to the dead context propagation, the wait context is propagated until an end node is
received or until an arc holds a token. Furthermore, the wait context is propagated by an
AND-join where all of the inputs have a wait context.
(a) w
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(b)
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(c) w w
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(e) w
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Figure 3.13: Transition relation for wait context propagation
Observations on Context Propagation
The transition relations of context propagation permit the following observations:
• Context changes terminate: It is intuitive that context propagation cannot run in an
(f)
infinite loop. It is easy to verify that the first two phases stop. The propagation of
w
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s
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