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these mappings using concepts from Petri net synthesis is presented in Sect. 14.6.
Section 14.7 summarizes the chapter.

14.2 Event-Driven Process Chains

The EPC is a business process modeling language for the representation of tem-
poral and logical dependencies of activities in a business process. It is utilized by
Scheer in the Architecture of Integrated Information Systems (ARIS) as the central
method for the conceptual integration of the functional, organizational, data, and
output perspective in information systems design. EPCs offer function type elements
to capture activities of a process and event type elements describing preconditions
and postconditions of functions. There are three kinds of connector types includ-
ing AND (symbol ^), OR (symbol _), and XOR (symbol ) for the definition of
complex routing rules. Connectors have either multiple incoming and one outgoing
arc (join connectors) or one incoming and multiple outgoing arcs (split connectors).
As a syntax rule, functions and events have to alternate either directly or indirectly
when they are linked via one or more connectors. OR- and XOR-splits after events
are not allowed as events cannot make decisions. Control-flow arcs are used to link
these elements.
The informal (or intended) semantics of an EPC can be described as follows. The
AND-split activates all subsequent branches concurrently; the XOR-split represents
a choice between one of several alternative branches; the OR-split triggers one, two,
or up to all of multiple branches. In both cases of the XOR- and OR-split, the activa-
tion conditions are given in events subsequent to the connector. Accordingly, splits
from an event to multiple functions should be avoided with XOR and OR, as the
activation conditions do not become clear in the model. The AND-join waits for
all incoming branches to complete and then propagates control to the subsequent
EPC element. The XOR-join merges alternative branches. The OR-join synchro-
nizes all active incoming branches. This feature is called nonlocality as the state of
all transitive predecessor nodes is considered.
Figure 14.1 shows the Carrier Appointment process from Fig. A.4 as an EPC
business process model. It is started when a carrier appointment is needed (start
event at the top). It activates the Prepare Route Guide and Estimate Trailer Usage
functions via an AND-split. The AND-join synchronizes the two branches and trig-
gers the Prepare Transportation Quote. In contrast to YAWL, EPC split-connectors
and join-connectors are elements of their own. A separate XOR-split describes
the following choice and the subsequent events define the respective conditions.
In case of Single Packaging (right branch), the Pickup Appointment is arranged
first, then the Delivery Appointment, and finally the Carrier Manifest is created.
In case of Less than Truck-Load (LTL), the Pickup Arrangement is done in parallel
to a decision whether the Delivery Appointment is done now or later. The OR-join
synchronizes the two active of the three incoming branches before the Bill of Lad-
ing is created. The Delivery Appointment can then be done afterwards if it has not