Petri Nets 2015

Slides and Lecture notes

• NEW THIS YEAR: Here is a preliminary version of the lecture notes for the course. We will make corrections until the course starts.
• Here is a summary containing all definitions and theorems presented in the lecture notes and in the exercises.
• This set of slides introduces some basic definitions:
  • Place, transition, arc, token, marking, firing rule.
  • Causality, conflict, concurrency.
  • Deadlock-freeness, liveness, boundedness
• In the last part of the course I'll use material from these books:
  • My book on Free Choice Petri Nets with J. Desel
  • My book on Unfoldings with K. Heljanko
  Notice that you can download them directly (for free) through the links above.
• This paper by Prof. Tadao Murata was published in 1989, but it still is a very nice introduction to Petri nets. The paper has over 9500 citations in Google Scholar!
• The Petri Nets World is a very interesting site with lots of information on all aspects of Petri nets. In particular you can find there a list of Petri net tools.
• There are many tools for editing and analyzing Petri nets.
  • A reasonable tool, very easy to install, although with some annoying bugs, is PIPE2 (Platform Independent Petri net Editor 2).
  • CPNTools is a very sophisticated, more professionally developed, tool for coloured Petri nets. It is also very easy to install, but more difficult to understand!
  • APT is command-line based Java tool with many functions for analyzing Petri nets, such as checking boundedness or liveness, finding traps, siphons and invariants and constructing reachability and coverability graphs.
  • LoLA is a command-line based tool written in C++ which can answer queries on Petri nets such as reachability or or deadlock checking.
• In SS13 I used my laptop as a blackboard, and I put the resulting handwritten notes online. This year I'll replace them by handouts.
  Anyway, just in case you find them useful, Here are the handwritten notes of SS13:
  • Backwards coverability algorithm:
    • Note1.jnt
    • Note1.pdf
  • Abstract backwards reachability algorithm.
    • Note2.jnt
    • Note2.pdf
  • The marking equation
    • Note3.jnt
    • Note3.pdf
  • Place and transition invariants
    • Note4.jnt
    • Note4.pdf
    • Note5.jnt
    • Note5.pdf
  • Structure theory
    • Struct1.jnt
    • Struct1.pdf
    • Struct2.jnt
    • Struct2.pdf
    • Struct3.jnt
    • Struct3.pdf
    • Struct4.jnt
    • Struct4.pdf

Exam of SS13

• Exam
• Solution