Tut2: Discrete-event Simulation with Applications to Computer Communication Systems Performance

Room: Diamant

Presenters:

Helena Szczerbicka University of Hannover, Germany
Kishor S. Trivedi, Duke University, Durham, NC, USA
Pawan K. Choudhary, Duke University, Durham, NC, USA

Abstract

As complexity in computer and communication systems increases, it is becoming increasingly hard to analyze system analytically. Similarly measurement based tools for system performance evaluation is becoming more expensive. In this tutorial, discrete event simulation as a model based technique will be introduced. It is widely used for the performance assessment of complex stochastic systems. Importance of applying a systematic methodology for building correct, problem dependent, and credible simulation models will also be discussed. These will be made evident by relevant experiments for different real-life problems and interpreting their results.

The tutorial will start providing motivation for using simulation as a methodology for solving problems, different types of simulation (steady state vs. terminating simulation), pros and cons of analytical versus simulative solution of a model. This will also include different classes of simulation tools existing today. It will be followed by steps involved in input data modelling of a simulation. Data collection, parameter estimation, goodness-of-fit test and random deviate generation will be discussed. A detailed analysis of discrete event simulation including steady state and terminating simulation will be presented. Use of data structures for realization of simulation will be discussed. Analysis of output results involving statistical concepts like point estimate, interval estimate, confidence interval and methods for generating it, will also be covered. Different approaches for deciding model validity will be described along with how model verification and validation relate to the model development process. Also various validation techniques will be defined.

The tutorial will also discuss some of the most widely used simulation packages like OPNET , ns-2 and CSIM . A broad and fair comparison of different packages will help one in deciding the best package for a given application. Also different methods of speeding the simulation like importance sampling, importance splitting and regenerative simulation will be taken. Finally the tutorial will provide several examples covering applications like TCP/IP, IEEE 802.11, and client-server application.

The tutorial will help in understanding simulation beyond just setting parameters in templates of simulation packages.

Presenters

Helena Szczerbicka , full Professor, holds the Chair for Modelling and Simulation, in Department of Computer Science at University of Hannover, Germany. She has a M.Sc. in Applied Mathematics and Ph.D. in Computer Science from Warsaw University of Technology, Poland. She has been on the faculties of Warsaw University, University of Karlsruhe, Germany and University of Bremen, Germany. She spent her sabbaticals at University of California, Berkeley and University of Central Florida, Orlando. Currently she leads a research group SIM-Simulation and Modelling. She works actively in Federation of European Simulation Societies (Eurosim), German Simulation Society (Asim) and Society for Computer Simulation (SCS). She is associate member of the McLeods Institutes of Simulation Sciences, USA. She conducts the FG4.5.3 Working Group Simulation and Artificial Intelligence of the German Society of Computer Science (GI). She has authored/co-authored more than 90 papers and one book. Her research interests are in the field of modelling performance and performability of large scale discrete dynamic systems. She is currently involved in establishing a Center for Integrated Simulation at University of Hannover.  

Kishor S. Trivedi holds the Hudson Chair in the Department of Electrical and Computer Engineering at Duke University, Durham, NC. His research interests are in reliability and performance assessment of computer and communication systems. He has published over 300 articles, lectured extensively on these topics and supervised 38 Ph.D. dissertations. He is the Duke-Site Director of an NSF Industry-University Cooperative Research Center between NC State University and Duke University. He is a co-designer of the HARP, SAVE, SHARPE, SPNP and SREPT modeling packages which have been widely circulated. He is the author of Probability and Statistics with Reliability, Queuing and Computer Science Applications, 2nd edition, published by Wiley. He is a Fellow of the IEEE and a Golden Core Member of IEEE Computer Society.

Pawan K. Choudhary received his bachelor's degree in ECE from Indian Institute of Technology, India, in 2002. He is currently pursuing Ph.D. at Duke University , Durham, North Carolina. His research interests are in simulative and analytic modeling of computer systems.