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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>A Short Introduction to the Regorous Compliance by Design Methodology</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Guido Governatori Data</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>CSIRO</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Australia</string-name>
        </contrib>
      </contrib-group>
      <abstract>
        <p>We provide a short outline of the compliance by design methodology proposed by Sadiq and Governatori to ensure compliance of business processes and its implementation in Regorous.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>Many de nitions of compliance have been proposed. However, regulatory compliance
is generally understood as the set of activities in place in an organisation to ensure
that the procedures, policies, processes and operations of the organisation comply
with the normative frameworks governing the business and environment where the
organisation operates. Sadiq, Governatori, and Naimiri [26] proposed a de nition of
regulatory compliance as a relation between two sets of speci cations, more precisely,
between the (formal) speci cations of a set of regulations and the (formal) speci cations
of a system. The de nition is further operationalised by focusing on formal models
of business processes for the speci cations of a system, and the relationship is that
activities performed to execute a business process do not violate the (relevant) set of
norms.</p>
      <p>
        In the past decade a plethora of compliance frameworks have been proposed; we
refer to [17, 25] for introductory material to general ideas about compliance, [
        <xref ref-type="bibr" rid="ref2 ref4 ref7">7, 4,
2</xref>
        ] for surveys and evaluations from the functionalities and business point of view,
and to [20, 19] for classi cations of the underlying approaches and their suitability to
properly represent normative requirements. The compliance-by-design methodology
and techniques advanced by [26], extended in [
        <xref ref-type="bibr" rid="ref15">15, 17</xref>
        ] and then implemented as
Regorous [
        <xref ref-type="bibr" rid="ref10">18, 10</xref>
        ] emerged as a strong ICT based solution for handling the regulatory
compliance of business processes [20, 19]; Regorous combines a conceptually sound
logical representation of norms with mathematical models of business processes and,
at the same time, it o ers a practical solution to determine whether business processes
comply with relevant normative frameworks.
      </p>
      <p>In the next section we give a very brief overview of business processes and we
argue that they can be used to represent a large class of systems. Then in Section 3
we discuss how to model norms in FCL, the rule language used in Regorous, then in
Section 4 we outline the compliance architecture for Regorous.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Business Processes</title>
      <p>
        A business process model is a self-contained, temporal and logical order in which
a set of activities are expected to be executed to achieve a business goal. Typically,
a process model describes what needs to be done and when (control ow), who is
going to do what (resources), and on what it is working on (data). Many di erent
formalisms (Petri-Nets, Process algebras, . . . ) and notations (BPMN, YAWL, EPC, . . . )
have been proposed to represent business process models (we refer to [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] for an
extensive presentation of business processes languages and modelling techniques,
and [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] for the technical foundations). Besides the di erence in notation, purposes,
and expressive power, business process languages typically contain the following
minimal set of elements: tasks, connectors (control ow gateways) and events. A task
corresponds to a (complex) business activity, and connectors (e.g., sequence, and-join,
and-split, (x)or-join, (x)or-split) de ne the relationships among tasks to be executed;
for the events we restrict ourselves to the start and end event. The combination of
tasks and connectors de nes the possible ways in which a process can be executed.
Where a possible execution, called process trace or simply trace, is a sequence of tasks
and events respecting the order given by the connectors. We will use TP to refer to the
set of traces of a process P . In other terms, TP represents all possible ways in which
the process can be executed.
      </p>
      <p>Compliance is not only about the tasks that an organisation has to perform to
achieve its business goals, but it is concerned also on their e ects (i.e., how the activities
in the tasks change the environment in which they operate), and the artifacts produced
by the tasks (for example, the data resulting from executing a task or modi ed by the
task) [21]. To capture this aspect [26] proposed to enrich process models with semantic
annotations. Each task in a process model can have attached to it a set of semantic
annotations. An annotation is just a set of formulas giving a (partial) description of
the environment in which a process operates. Then, it is possible to associate to each
task in a trace a set of formulas corresponding to the state of the environment after
the task has been executed in the particular trace. Notice, that di erent traces can
results in di erent states, even if the tasks in the traces are the same. In addition, even
if the end states are the same, the intermediate states can be di erent. Accordingly,
we extend the notion of trace. First of all, we introduce the function</p>
      <p>State : TP</p>
      <p>N 7! 2L;
where N is the set of natural numbers and L is the set of formulas of the language
used to model the annotations.
3</p>
    </sec>
    <sec id="sec-3">
      <title>Modelling and Reasoning with Norms</title>
      <p>As we have already discussed to check whether a business process is compliant with
a relevant regulation, we need an annotated business process model and the formal
representation of the regulation. The annotations are attached to the tasks of the
process, and it can be used to record the data, resources and other information related
to the single tasks in a process.</p>
      <p>
        For the formal representation of the regulation we use FCL [
        <xref ref-type="bibr" rid="ref15 ref9">9, 15</xref>
        ]. FCL is a simple,
e cient, exible rule based logic. FCL has been obtained from the combination of
defeasible logic (for the e cient and natural treatment of exceptions, which are a
common feature in normative reasoning) [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] and a deontic logic of violations [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ]. In
FCL a norm is represented by a rule
      </p>
      <p>a1; : : : ; an ) c
Where a1; : : : ; an are the conditions of applicability of the norm/rule and c is the
normative e ect of the norm/rule. FCL distinguishes two normative e ects: the rst is
that of introducing a de nition for a new term; the second is</p>
      <p>
        The second normative e ect is that of triggering obligations and other deontic
notions. FCL supports all deontic notions (normative requirements) proposed and
classi ed for compliance purposes in [
        <xref ref-type="bibr" rid="ref8">8, 22</xref>
        ], see Figure 1. In addition it has mechanisms
to terminate and remove obligations (see [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ] for full details). For obligations and
permission we use the following notation:
• »P¼p: p is permitted;
• »OM¼p: there is a maintenance obligation for p;
• »OAPP¼p: there is an achievement preemptive and perdurant obligation for p;
• »OAPNP¼p: there is an achievement preemptive and non-perdurant obligation for p;
• »OANPP¼p: there is an achievement non preemptive and perdurant obligation for p;
• »OANPNP¼p: there is an achievement non preemptive and non-perdurant obligation
for p.
      </p>
      <p>
        Compensations are implemented based on the notion of ‘reparation chain’ [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ]. A
      </p>
    </sec>
    <sec id="sec-4">
      <title>Compliance</title>
      <p>Legalese Formalisation
4</p>
      <p>Compliance
Rule Base
Rule1
Rule2
Rule3
Rule4
Rule5
Rule6
Rule7
Rule8
Rule9
...</p>
      <p>Recommendation Sub-system</p>
      <p>
        recommendations
as implemented in Regorous. Given an annotated process and the formalisation of the
relevant regulation, we can use the algorithm initially proposed in [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ] to determine
whether the annotated process model is compliant. The procedure runs as follows:
1FCL is agnostic about the nature of the literals it uses. They can represent tasks (activities executed in a
process), or propositions representing state variables and the happening of events.
reparation chair is an expression
      </p>
      <p>O1c1</p>
      <p>O2c</p>
      <p>Oncn;
where each Oi is an obligation, and each ci is the content of the obligation (modelled
by a literal). The meaning of a reparation chain is that we have that c1 is obligatory, but
if the obligation of c1 is violated, i.e., we have :c1, then the violation is compensated
by c2 (which is then obligatory). But if even O2c2 is violated, then this violation is
compensated by c3 which, after the violation of c2, becomes obligatory, and so on.</p>
      <p>
        The reasoning behind FCL is the standard mechanism of defeasible logic [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]
extend to handle the deontic notions. We refer the interested readers to [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] for a full
description and all technical details.
      </p>
      <p>Each task in a process model can have attached to it a set of semantic annotations. In our
approach the semantic annotations are literals in the language of FCL1, representing
the e ects of the tasks. Figure 2 depicts the architecture of the compliance methodology
Compliance Checker</p>
      <p>Annotated Business Process</p>
      <p>Input
Obligations
if sis
at ly
wh ana</p>
      <p>Logical State
Representation</p>
      <p>State(t,1)
State(t,2)
State(t,3)
State(t,4)</p>
      <p>A process is (fully) compliant if and only if all traces are compliant (all obligations
have been ful lled or if violated they have been compensated). A process is partially
compliant if there is at least one trace that is compliant.</p>
      <p>
        Regorous proved to be conceptually sound for the modelling of norms [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ] against
underlying semantics advanced in [
        <xref ref-type="bibr" rid="ref8">8, 22</xref>
        ] It does not su er from the problem of wrong
representation of norms a ecting formalism based on possible world semantics [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]
and temporal logic based compliance frameworks [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ].
      </p>
      <p>
        Notice that the Regorous’s strategy to examine all traces (with the proviso that
all loops are unfolded once) is optimal, in the sense that [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] proved that the problem
of determining whether a process is weakly compliant is NP-complete and
CoNPcomplete for the case of full compliance.
      </p>
      <p>It is worth noting that the core notion we require is that of a trace, which is can
be simply understood as a sequence of relevant event. Thus, the idea presented in
this section and used in Section 4 can be adopted for a large variety systems (all we
need is a sequence of events, each with a set of semantic annotations attached to each
event). Also, it can be used at di erent stages of the life-cycle of a business processes
design-time, run-time and auditing. At design time, we have to simulate all possible
execution of the process with abstract data, at run time, we use the data generated
by an instance (case) of the process, and we can evaluate if up to the current task the
process is compliant, determine what obligations are currently in force and predict
if the instance is going to be compliant. Finally, it is possible to replay the entire log
(split in cases) for auditing purposes, eventually retrieving the data from log of from
the databases related to the processes [21, 23].
4.1</p>
      <p>Implementation and Evaluation
As we have already alluded to our compliance-by-design methodology has been
implemented in Regorous which has been implemented on top of Eclipse. For the
representation of process models, it uses the Eclipse Activiti BPMN 2.0 plugin, extended with
features to allow users to add semantic annotations to the tasks in the process model.
Regorous is process model agnostic, this means that while the current implementation
is based on BPMN all Regorous needs is to have a description of the process and the
annotations for each task. A module of Regorous take the description of the process
and generates the execution traces corresponding to the process. After the traces are
generated, it implements the algorithm outlined above, where it uses the SPINdle rule
engine [24] for the evaluation of the FCL rules. In case a process is not compliant (or
if it is only weakly compliant) Regorous reports the traces, tasks, rules and obligations
involved in the non compliance issues.</p>
      <p>
        Regorous was successfully tested in a number of pilot project with industry partners
in banking, insurance, telecommunications and building sectors. See [25, 18] for the
results of the evaluation in the telecommunication sector for compliance against the
Australian Customers Protection Code (C628-2012). As we noted above, in general,
the problem of determine whether a business process is compliant is computationally
intractable. However, Regorous adopts a series of strategies to reduce the number of
computations [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. Furthermore, experience with the pilot project seem to indicate
the theoretical computational limits, do not really a ect practical applications.
17. Governatori, G., Sadiq, S.: The Journey to Business Process Compliance. In: Cardoso, J., van der Aalst,
      </p>
      <p>W. (eds.) Handbook of Research on BPM, pp. 426–454. IGI Global (2009)
18. Governatori, G., Shek, S.: Regorous: A Business Process Compliance Checker. In: Francesconi, E., Verheij,</p>
      <p>B. (eds.) ICAIL 2013, pp. 245–246. ACM, New York (2013)
19. Hashmi, M., Governatori, G.: Norms Modeling Constructs of Business Process Compliance Management</p>
      <p>Frameworks: A Conceptual Evaluation. Arti cial Intelligence and Law (2017)
20. Hashmi, M., Governatori, G., Lam, H.-P., Wynn, M.T.: Are We Done with Business Process Compliance:</p>
      <p>State-of-the-Art and Challenges Ahead. Knowledge and Information Systems (2018)
21. Hashmi, M., Governatori, G., Wynn, M.T.: Business Process Data Compliance. In: Bikakis, A., Giurca, A.</p>
      <p>(eds.) RuleML 2012, LNCS, vol. 7438, pp. 32–46. Springer, Heidelberg (2012)
22. Hashmi, M., Governatori, G., Wynn, M.T.: Normative Requirements for Regulatory Compliance: An</p>
      <p>Abstract Formal Framework. Information Systems Frontiers 18(3), 429–455 (2016)
23. Islam, M.B., Governatori, G.: Exposing the RuleRS: a rule-based architecture for decision support systems.</p>
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24. Lam, H.-P., Governatori, G.: The Making of SPINdle. In: Governatori, G., Hall, J., Paschke, A. (eds.)</p>
      <p>RuleML 2009, LNCS, vol. 5858, pp. 315–322. Springer, Heidelberg (2009)
25. Sadiq, S., Governatori, G.: Managing Regulatory Compliance in Business Processes. In: vom Brocke, J.,
Rosemann, M. (eds.) Handbook of Business Process Management 2nd edition, International Handbooks
on Information Systems, vol. 2, pp. 265–288. Springer, Berlin-Heidelberg (2015)
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    </sec>
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