Distributed Computing
ETH Zurich

Discrete Event Systems (HS 2010)

Over the past few decades the rapid evolution of computing, communication, and information technologies has brought about the proliferation of new dynamic systems. A significant part of activity in these systems is governed by operational rules designed by humans. The dynamics of these systems are characterized by asynchronous occurrences of discrete events, some controlled (e.g. hitting a keyboard key, sending a message), some not (e.g. spontaneous failure, packet loss).

The mathematical arsenal centered around differential equations that has been employed in systems engineering to model and study processes governed by the laws of nature is often inadequate or inappropriate for discrete event systems. The challenge is to develop new modeling frameworks, analysis techniques, design tools, testing methods, and optimization processes for this new generation of systems.

In this lecture we give an introduction to discrete event systems. We start out the course by studying popular models of discrete event systems, such as automata and Petri nets. In the second part of the course we analyze discrete event systems. We first examine discrete event systems from an average-case perspective: we model discrete events as stochastic processes, and then apply Markov chains and queuing theory for an understanding of the typical behavior of a system. In the last part of the course we analyze discrete event systems from a worst-case perspective using the theory of online algorithms and adversarial queuing.

Course language: German

Lecture by Prof. Roger Wattenhofer and Dr. Kai Lampka Thursday 13.15-15.00 @ ETZ E9 (new room!) .

Exercises by Jasmin Smula and Tobias Langner Thursday 15.15-16.45 @ ETZ E9 (new room!).


Exam Review

After the exam grades have been published in myStudies, you can take a look at your exam until the end of April. To do so, please visit our secretary Tanja Lantz (office ETZ G88) on Monday, Wednesday, or Friday during office hours.


Exam

The exam is scheduled for Tuesday, 25. January 2011. from 9:00 to 12:00 @ HG E41.

You may use any written material like scripts, your own notes, exercise sheets, books, etc...
All electronical devices (computers, calculators, cell phones, etc...) are not allowed during the exam!


Sample Exam

In order to get a feeling of our exam style, you may have a look at this sample exam and the sample solutions (please excuse the apparent random choice of language in the exercises/solutions).


Question Session

We will hold a question session in which we (try to) answer your questions about this lecture. The session is on Thursday, 20. January 2011, 9:00 - 11:00 at ETZ E 81.
Please send us your questions ahead of time, at the latest until Wednesday, 19. January 2010 at 14:00 by email to either of the assistants.


Exercise Proceedings

At the beginning of every lecture week, we will publish a new exercise sheet here. This exercise sheet is intended to be solved during the exercise session on Thursday where two tutors will be available to assist you and to answer potential questions.

You can hand in your solutions for correction after the exercise session on a voluntary basis. This is not mandatory since a Testat is not required to be admitted to the final exam (see here for further information).


Question Wiki

We try to keep all answers to questions send to us by mail (but not the ones we answer in the exercise sessions, though) publicly available on this Question Wiki such that everyone can profit.



Lecture Notes

The following documents are lecture notes of former students. (We provide no guarantee that these documents are correct!)



Lecture material


Title Slides Additional Material References

Chapter 0
Introduction
23/09/2010
PDF 1:1
PDF 4:1
[cassandras]

Chapter 1
Automata and Languages
23/09/2010
PDF 1:1
PDF 4:1
[sipser]
[exorciser]

Chapter 2
Smarter Automata
07/10/2010
PDF 1:1
PDF 4:1
[sipser]
[exorciser]

Chapter 3
Stochastic Discrete Event Systems
22/10/2010
PDF 1:1
PDF 4:1
[bertsekas]
[schickinger]

Chapter 4
Worst-Case Event Systems
15/11/2010
PDF 1:1
PDF 4:1
Mario und Luigi
[borodin]
[fiat]
[hochbaum]

Chapter 5
Network Calculus
01/12/2010
PDF 1:1
PDF 4:1
[boudec]

Chapter 6a
Background Material
07/12/2010
PDF 1:1
PDF 4:1

Chapter 6b
Petri Nets
07/12/2010
PDF 1:1
PDF 4:1
[murata]

Chapter 6c
CTL Model Checking
15/12/2010
PDF 1:1
PDF 4:1
[baier]

Chapter 6d
Timed Automata
20/12/2010
PDF 1:1
PDF 4:1


Exercise material


Title Exercise Sample Solution

Exercise 1
Assigned: 20/09/2010
Due: 23/09/2010
Download Download

Exercise 2
Assigned: 27/09/2010
Due: 30/09/2010
Download Download

Exercise 3
Assigned: 04/10/2010
Due: 07/10/2010
Download Download

Exercise 4
Assigned: 11/10/2010
Due: 14/10/2010
Download Download

Exercise 5
Assigned: 18/10/2010
Due: 21/10/2010
Download Download

Exercise 6
Assigned: 26/10/2010
Due: 28/10/2010
Download Download

Exercise 7
Assigned: 01/11/2010
Due: 4/11/2010
Download Download

Exercise 8
Assigned: 10/11/2010
Due: 11/11/2010
Download Download

Exercise 9
Assigned: 15/11/2010
Due: 18/11/2010
Download Download

Exercise 10
Assigned: 22/11/2010
Due: 25/11/2010
Download Download

Exercise 11
Assigned: 29/11/2010
Due: 02/12/2010
Download Download

Exercise 12
Assigned: 06/12/2010
Due: 09/12/2010
Download Download

Exercise 13
Assigned: 13/12/2010
Due: 16/12/2010
Download Download

Exercise 14
Assigned: 20/12/2008
Due: 23/12/2009
Download Download UppaalSolutions.zip


'Testat'

You do not need a Testat to attend the final exam. However, if you need a Testat, e.g. because you don't intend to take the final exam, but need an attestation that you attended the class, you need to hand in at least 80% of the exercises.

References

[exorciser] Exorciser - Interaktive Lernsoftware für theoretische Informatik
Download
[bertsekas] Data Networks
Dimitri Bertsekas, Robert Gallager.
Prentice Hall, 1991, ISBN: 0132009161
[borodin] Online Computation and Competitive Analysis
Allan Borodin, Ran El-Yaniv.
Cambridge University Press, 1998
[boudec] Network Calculus
J.-Y. Le Boudec, P. Thiran.
Springer, 2001
[cassandras] Introduction to Discrete Event Systems
Christos Cassandras, Stephane Lafortune.
Kluwer Academic Publishers, 1999, ISBN 0-7923-8609-4
[fiat] Online Algorithms: The State of the Art
A. Fiat and G. Woeginger.
[hochbaum] Approximation Algorithms for NP-hard Problems (Chapter 13 by S. Irani, A. Karlin)
D. Hochbaum.
[murata] Petri Nets: Properties, Analysis and Applications
Tadao Murata.
Proceedings of the IEEE, vol. 99, issue 4, April 1989. pp. 541--580
Download
[schickinger] Diskrete Strukturen (Band 2: Wahrscheinlichkeitstheorie und Statistik)
T. Schickinger, A. Steger.
Springer, Berlin, 2001
[sipser] Introduction to the Theory of Computation
Michael Sipser.
PWS Publishing Company, 1996, ISBN 053494728X
[baier] Principles of Model Checking
Christel Baier and Joost-Pieter Katoen.
MIT Press