Contact

Lecturers:

Teaching assistant:

Location & time

Lecture: Thursday 14:15–16:00 in HG D 7.2

Exercises: Thursday 16:15–18:00 in HG D 7.2

About this course

Discrete event systems are systems whose behaviour is driven by the occurrence of asynchronous, discrete events rather than by the steady tick of continuous time — think of packets arriving at a router, jobs entering a queue, or tokens moving through a workflow. This course introduces the modeling frameworks, analysis techniques, and verification tools used to reason about such systems rigorously.

By the end of the course you will be able to:

  1. describe families of languages and the abstract machines that recognise them, and reason about what can and cannot be computed;
  2. model and analyse the long-run and average behaviour of stochastic systems using Markov chains and queueing theory;
  3. specify desired properties of a system and verify them formally using finite-automata techniques and Petri nets.

Course structure

The course is organised in three parts:

  • Part 1 — Computability Models (Prof. Vanbever): regular and non-regular languages, automata, and the limits of computation.
  • Part 2 — Analysis Methods (Prof. Vanbever): Markov chains and queueing theory.
  • Part 3 — Formal Verification (Prof. Josipović): finite-automata verification and Petri nets.

Grading and organization

The course is graded entirely on a written final exam. The exam is open book: all written material (script, slides, your own notes, exercises, books) is allowed. No electronic devices are permitted, except for a non-connected calculator. The exam is in English, and you will not be tested on material that was not covered during the lectures.

Weekly exercise sessions accompany the lectures. The exercises are not graded, but working through them is the best way to prepare for the exam — solutions are discussed in the session and posted here.

Literature

The course is self-contained; the following references are recommended for going deeper:

  • M. Sipser, Introduction to the Theory of Computation, PWS/Cengage.
  • C. Cassandras & S. Lafortune, Introduction to Discrete Event Systems, Springer.
  • D. Bertsekas & R. Gallager, Data Networks, Prentice Hall.
  • T. Schickinger & A. Steger, Diskrete Strukturen (Band 2), Springer.
The schedule below is tentative and may still be adjusted. Lecture and exercise materials are posted here as the semester progresses.
Part 1
Computability Models
Week 1Sep 17
Lecture Introduction & Regular Languages
  1. What is a discrete event system?
  2. Languages and finite automata (DFA / NFA)
  3. Regular expressions

Materials

Exercise
Week 2Sep 24
Lecture Regular Languages
  1. Equivalence of DFAs, NFAs, and regular expressions
  2. Closure properties
  3. Minimisation

Materials

Exercise

Materials

Week 3Oct 01
Lecture Non-Regular Languages
  1. Limits of regular languages: the pumping lemma
  2. Context-free grammars and languages

Materials

  • Slides — coming soon
Exercise

Materials

  • Exercise sheet — coming soon
Week 4Oct 08
Lecture Non-Regular Languages
  1. Pushdown automata
  2. The tandem (pumping) lemma for context-free languages

Materials

  • Slides — coming soon
Exercise

Materials

  • Exercise sheet — coming soon
Week 5Oct 15
Lecture Non-Regular Languages
  1. Closure properties of context-free languages
  2. The Chomsky hierarchy
  3. Turing machines

Materials

  • Slides — coming soon
Exercise

Materials

  • Exercise sheet — coming soon
Part 2
Analysis Methods
Week 6Oct 22
Lecture Markov Chains
  1. Discrete-time Markov chains
  2. Stationary distributions and convergence
  3. Application: PageRank

Materials

  • Slides — coming soon
Exercise

Materials

  • Exercise sheet — coming soon
Week 7Oct 29
Lecture Queueing
  1. Poisson processes and birth–death chains
  2. The M/M/1 queue
  3. Little's law

Materials

  • Slides — coming soon
Exercise

Materials

  • Exercise sheet — coming soon
Week 8Nov 05
Lecture Queueing
  1. More queueing models (M/M/k, M/G/1)
  2. Networks of queues

Materials

  • Slides — coming soon
Exercise

Materials

  • Exercise sheet — coming soon
Part 3
Formal Verification
Week 9Nov 12
Lecture Finite Automata Verification
  1. Modeling systems and specifications
  2. Safety and liveness properties

Materials

  • Slides — coming soon
Exercise

Materials

  • Exercise sheet — coming soon
Week 10Nov 19
Lecture Finite Automata Verification
  1. Temporal logic and model checking
  2. Automata-based verification

Materials

  • Slides — coming soon
Exercise

Materials

  • Exercise sheet — coming soon
Week 11Nov 26
Lecture Verification — topic TBD

Additional verification lecture — topic to be announced.

Materials

  • Slides — coming soon
Exercise

Materials

  • Exercise sheet — coming soon
Week 12Dec 03
Lecture Petri Nets
  1. Places, transitions, and tokens
  2. Modeling concurrency

Materials

  • Slides — coming soon
Exercise

Materials

  • Exercise sheet — coming soon
Week 13Dec 10
Lecture Petri Nets
  1. Reachability and behavioural properties
  2. Analysis techniques

Materials

  • Slides — coming soon
Exercise

Materials

  • Exercise sheet — coming soon
Wrap-up
Recap
Week 14Dec 17
Lecture Recap & Exam Briefing
  1. Course review
  2. Exam format and Q&A

Materials

  • Slides — coming soon
Q&A Exam preparation

Exam

The final exam is a written, open-book exam. All written material (script, slides, your own notes, exercises, books) is allowed; no electronic devices are permitted, except for a non-connected calculator. The exam is in English, and you will not be tested on material that was not covered during the lectures.

Previous exams

Heads up: the set of topics covered in this course has changed over the years — lecturers, chapters, and emphasis differ between editions (for example, the “Online algorithms” chapter is not part of the 2026 edition). Use these past exams to practise, but treat questions on topics we did not cover this year as out of scope, and don't assume this year's exam will match their structure.

With solutions:

Without solutions: