Successfully reported this slideshow.

Marlon Dumas @ BPMN 2010


Published on

Published in: Business, Technology
  • Be the first to comment

  • Be the first to like this

Marlon Dumas @ BPMN 2010

  1. 1. Unraveling Unstructured Process Models Marlon Dumas University of Tartu, Estonia Joint work with Artem Polyvyanyy and Luciano García-Bañuelos Invited Talk, BPMN’2010 Workshop, Potsdam, 14 Oct. 2010
  2. 2. Poll: Which desk do you prefer? 2
  3. 3. Poll: Which model do you prefer? 3
  4. 4. The Problem •  Premise: Structured is “better” –  Easier to understand –  Easier to analyze –  Easier to automatically layout –  Easier to abstract (zoom-out) •  We know not all models can be structured… •  Which ones can, which ones can’t? 4
  5. 5. Analysis of Structured Models 5 CTparallel = Max{T1, T2,…, TM} CT = p1T1+p2T2+…+pmTm= CT = T/(1-r) CT = T1+T2+…+ Tm Laguna & Marklund (2005): Business Process Modeling, Simulation and Design
  6. 6. Automated Layout and Abstraction 6 Wil van der Aalst et al., Process Mining Tutorial
  7. 7. A Bit of History 7 1968 1969 1970s (and 80s)
  8. 8. 20 years (and 200 papers) later… •  Everything can be structured if you accept to break and continue •  Everyone forgot to release their implementation (they were ashamed since it was full of GOTOs) 8
  9. 9. 40 years (and 400 papers) later •  We can structure any BPMN diagram, except: –  “Incorrect” ones –  Cycles with multiple exit points –  Z-structures –  Inclusive join gateways, complex gateways and other demons •  Try it out: 9
  10. 10. Corollary (if you care) •  Any (sound) BPMN model can be transformed into an equivalent (readable) BPEL process definition 10 •  If BPEL had break/continue statements or we use boolean variables to simulate break/continue statememts •  And the BPMN model does not have inclusive join gateways, complex gateways and other demons •  And some other minor details not worth mentioning
  11. 11. 11 Behavioral Equivalence Preserves the level of concurrency in a process model Sequential simulation of a process model Fully concurrent bisimilar (FCB) Weakly bisimilar Weakly bisimilar Sequential simulation of a process model
  12. 12. Starting Point – Process Structure Tree 12 Johnson et al. (PLDI’1994), Vanhatalo et al. (BPM’2008)
  13. 13. 13 Taxonomy of Process Fragments ■  Trivials, polygons, and bonds are structured fragments ■  Rigids are “unstructured” 13
  14. 14. Homogeneous XOR Rigid 14
  15. 15. Homogeneous AND Rigid 15
  16. 16. Block-structured version… 16
  17. 17. Homogeneous AND Rigid that cannot be structured •  Causal rules: –  {A, B}  { C } –  { B }  { D } •  Overlap on the left-hand side of the rules
  18. 18. Compare to this… •  Causal relations –  {A, B}  {C, D}
  19. 19. Heterogeneous Acyclic Rigid 19
  20. 20. Equivalent Structured Fragment 20
  21. 21. The Key Ingredient: Unfoldings An unfolding is a representation of a net without “merge” points A complete prefix unfolding is a finite initial part of the unfolding that contains full information about the reachable states 21
  22. 22. Ordering Relations ■ Two transitions of an occurrence net are in one of the following relations: □  A and B are in causal relation (A>B), iff there exists a path from A to B □  A and B are in conflict (A#B), iff there are two transitions t1, t2 that share an input place and there is a path from t1 to A and a path from t2 to B □  A and B are in concurrency (A||B) relation iff A and B are neither in causal, nor in conflict relation A>C1 B>D2 B#A A#D2 C2||D2 D2||C2 22
  23. 23. FCB and Ordering Relations Two process models are FCB-equivalent … … if and only if, (complete prefix) unfoldings of both models expose same ordering relations 23
  24. 24. Structuring Process Models Compute ordering relations of the (unstructured) process model Construct a block-structured process model from ordering relations 24
  25. 25. Ordering Relations Graph An ordering relations graph 25
  26. 26. Modular Decomposition Tree (MDT)   The MDT is unique and can be computed in linear time The MDT ■  A linear (L) module is a total order on a set of nodes of a graph ■  A complete (C) module is a complete graph, or a clique ■  A primitive (P) module is neither trivial, nor linear, nor complete   A module is a set of edges with uniform structure 26
  27. 27. 27 Structuring Acyclic Process Models A primitive module Let G be an ordering relations graph. The MDT of G has no primitive module, iff there exists a well-structured process model W such that G is the ordering relations graph of W.
  28. 28. Heterogeneous Cyclic Rigid 28
  29. 29. For further details… Download and try: • • Perspectives: •  Analyze •  Decompose (e.g. for distributed execution) •  Refactor (extract duplicate fragments into subprocesses) •  Visualize 29