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problem. No specific implementations exists for this
approach. (Xiang et al., 2021b) proposes a tool which
allows the detection of data inconsistency of work-
flow processes based on unfolding techniques simi-
lar to the ones in (Xiang et al., 2017). The authors
use the guard-driven reachability graph from (Xiang
and Liu, 2020) to apply model-checking techniques
for detecting deadlocks and proper-termination, but
no other data-flow errors are detected. Because the
configuration graph does not take into consideration
all the possible values of guards, incorrect results can
be obtained regarding the proper termination.
Our approach uses the WFD-net proposed in
(Tr
ˇ
cka et al., 2009), allowing read, write, delete op-
erations and guards for transitions. Instead of trans-
forming a model of the process into Petri nets in or-
der to apply model-checking techniques (as in (Tr
ˇ
cka
et al., 2009; von Stackelberg et al., 2014; M
¨
ulle et al.,
2019)), we provide a formalization of workflows with
data in Maude, by specifying WFD-nets as theories in
the rewriting logic. This approach permits the specifi-
cation of configurations as states of the Kripke struc-
ture that will be used by the LTL checker in Maude.
The proposed configuration embeds all the data infor-
mation needed to describe the data anti-patterns.
The existing approaches do not permit the specifi-
cation of data in the initial state of the process or the
specification of conditions on data when the workflow
terminates, as we propose in this paper.
7 CONCLUSIONS
In this paper we have proposed the specification of
workflow nets with data in Maude, providing a for-
mal semantics for WFD-nets. We have introduced
two notions of soundness to describe the correctness
of workflows with data. Unlike other notions of cor-
rectness defined for workflows with data, in which
the termination condition only requires that the final
marking (o) should be reached, these properties re-
quire that at least one data element or all data ele-
ments from a given set should be present when the
workflow terminates. We have formalized these cor-
rectness properties using the CTL temporal logic. We
have also formalized the data-flow errors (redundant
data, missing data, lost data and inconsistent data) us-
ing the LTL temporal logic. The verification of prop-
erties can be done using the LTL model checker from
Maude and the umaudemc utility for Maude.
In ongoing work, we plan to identify and formal-
ize other data flow errors, study soundness with other
types of termination requirements and also consider
the modelling of security constraints over data ele-
ments. We intend to develop a tool for editing WFD-
nets, that will also automate the transformation from
WFD-nets to Maude specifications and will permit the
verification of properties.
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