Model Transformations for Business Process Analysis and Execution

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Model Transformations for Business Process
Analysis and Execution

• Marlon Dumas
• University of Tartu

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Business Process Management (BPM)

• Collection of methods and techniques to design,
  analyze, execute and monitor business operations
  involving humans, software, information and
  physical artifacts using process models.

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OK, so what is a process model?

• Collection of inter-dependent activities whose
  collective performance is intended to achieve a
  goal such as delivering a product or a service.
• E,g. order-to-cash, procure-to-pay,
  issue-to-resolution
• Animated example

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Process models serve many purposes
ProcessImprovement
Compliance /Risk Management
Process Documentation
KnowledgeManagement
Process CostAnalysis / Simulation
EnterpriseSystems
EnterpriseArchitecture
WorkflowManagement
DocumentManagement
Software Evaluation/ Selection
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they have many faces
Abstract Models EPC, BPMN Communication,
simulation, activity-based costing
Detailed Models BPEL, State Machines Data types,
conditions, data mappings, fault
handling Integration, testing, deployment
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and can be seen from many perspectives

• Control-flow
• Data
• Resource
• Operational

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Many in one, or one in many?

• The thing can be many in one sense, but also
  can be one in another sense.
• Imam Ghazali
• Revival of Religious Sciences 

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Process ModellingDealing with Multiplicity

• Multiple modelling languages (meta-models)
• Multiple modelling viewpoints
• Control-flow view vs. data view
• Public views (protocols) vs. private views
• Multiple abstraction levels
• High-level tasks, performance metrics...
• Low-level data transformations, application
  bindings...

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Process Modelling Notations

• Business Process Modelling Notation (BPMN)
• Event-driven Process Chains (EPC)
• Business Process Execution Language (BPEL)
• State machines and variants (e.g. IBM Business
  State Machine, WWF)
• Petri nets (and variants, e.g. YAWL)

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Model transformations

• BPMN-to-BPEL
• Purpose Transform models produced by analysts
  into models for developers (and vice-versa)
• Commonly supported in commercial tool, but in a
  limited manner
• BPEL-to-Petri nets
• For analysis verification
• BPMN-to-Petri nets
• For analysis verification (e.g.
  deadlock-freeness)

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BPMN from 10 000 miles
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BPMN A more detailed view
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Quick BPMN example
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BPEL from 10 000 miles

• Basic activities ltassigngt, ltinvokegt, ltreceivegt
• Sequential flow ltsequencegt, ltwhilegt, ltswitchgt
• Block-structured parallel flow ltflowgt
• Graph-oriented (parallel) flow ltlinkgt
• Event-action rules ltonEventgt
• Other constructs not relevant to this talk
• Only partially supported by some tools

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A quick BPEL example

• ltsequencegt
• ltinvoke check stock availability /gt
• ltswitch () /gt
• ltcase rejectgt ltinvoke order rejection
  /gt lt/casegt
• ltotherwisegt
• ltsequencegt
• ltinvoke order acceptance /gt
• ltflowgt ltinvoke invoicing /gt
• ltinvoke ship goods /gt
• lt/flowgt
• lt/sequencegt lt/otherwisegt lt/switchgt
  lt/sequencegt

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BPMN-to-BPEL Some monsters!
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BPMN-to-BPEL (from 10 000 miles)

• Repeat until reduction to a single node
• Identify a structured quasi-structured SESE
  region ? Fold into a BPEL structured activity
• Identify irreducible SESE regions without
  parallelism ? Apply Goto?While
  transformations, repeat from 1
• Identify acyclic fragments with concurrency ?
  Fold into a BPEL activity with control links
• Identify minimal unstructured components ?
  BPEL event handlers

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BPMN-BPEL Structured Components
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BPMN-BPEL Structured Components
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BPMN-BPEL Structured Components
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Example Only Structured Components
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BPMN-to-BPEL Acyclic component

• Proposition Every acyclic BPMN component with a
  single entry point and a single exit point that
  is 1-safe and sound can be mapped to a BPEL Flow
  with links

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ExampleStructuredAcyclic Components
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Minimizing the use of control links
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For the rest

• Identify a minimal SESE region that is neither
  structured nor acyclic
• For each action in the component, retrieve
• All actions that immediately precede it
• All actions that immediately follow it
• For each action, code the following behaviour
  using event-action rules
• Wait for a suitable combination of predecessors
  to complete
• Perform action
• Notify completion to all successors

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BPEL-to-Petri netApplication to Conformance
Checking
Services
Services
abstract BPEL process
Services
Conformance?
SOAP Messages
Translation
Monitoring / Correlation
Petri net model
Event Log
Conformance Checking!
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From BPEL to WF-nets
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Petri net-based Conformance Checking

• Objectives
• quantitatively measure conformance
• locate deviations

Conformance?
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Conformance Checking Fitness
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Conformance Checking Fitness
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Measuring fitness Log replay analysis
missing tokens remaining tokens
0 1
consumed tokens produced tokens
0 0
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Measuring fitness Log replay analysis
1 2
0 0
missing tokens remaining tokens
consumed tokens produced tokens
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Measuring fitness Log replay analysis
2 4
0 0
missing tokens remaining tokens
consumed tokens produced tokens
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Measuring fitness Log replay analysis
3 5
0 0
missing tokens remaining tokens
consumed tokens produced tokens
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Measuring fitness Log replay analysis
5 6
0 0
missing tokens remaining tokens
consumed tokens produced tokens
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Measuring fitness Log replay analysis
6 7
0 0
missing tokens remaining tokens
consumed tokens produced tokens
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Measuring fitness Log replay analysis
7 7
0 0
missing tokens remaining tokens
consumed tokens produced tokens
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Measuring fitness Log replay analysis
9 9
0 0
missing tokens remaining tokens
consumed tokens produced tokens
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Measuring fitness Log replay analysis
9 9
0 0
missing tokens remaining tokens
consumed tokens produced tokens
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Measuring fitness Log replay analysis
0 1
0 0
missing tokens remaining tokens
consumed tokens produced tokens
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Measuring fitness Log replay analysis
1 2
0 0
missing tokens remaining tokens
consumed tokens produced tokens
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Measuring fitness Log replay analysis
2 4
1 0
missing tokens remaining tokens
consumed tokens produced tokens
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Measuring fitness Log replay analysis
3 5
1 0
missing tokens remaining tokens
consumed tokens produced tokens
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Measuring fitness Log replay analysis
4 6
1 0
missing tokens remaining tokens
consumed tokens produced tokens
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Measuring fitness Log replay analysis
6 7
1 0
missing tokens remaining tokens
consumed tokens produced tokens
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Measuring fitness Log replay analysis
7 8
1 0
missing tokens remaining tokens
consumed tokens produced tokens
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Measuring fitness Log replay analysis
8 8
1 1
missing tokens remaining tokens
consumed tokens produced tokens
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Measuring fitness Log replay analysis
8 8
1 1
missing tokens remaining tokens
consumed tokens produced tokens
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Measuring fitness Log replay analysis
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Measuring fitness Log replay analysis
f 1.0
f 0.540
f 0.955
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Conformance Checking - Appropriateness

100 fitness but not sufficiently specific from
behavioral point of view.
100 fitness but not represented in structurally
suitable way.
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Ongoing work

• Reversible BPMN ? BPEL transformation
• Two-way transformation BPEL ? FSM
• Application to automated service composition
• BPEL ? FSM not too difficult
• FSM ? BPEL more exciting, e.g.

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References