CS433: Modeling and Simulation

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CS433 Modeling and Simulation

• Al-Imam Mohammad Ibn Saud University

Lecture 01 Introduction
Dr. Anis Koubâa
10 October 2009
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Who I Am?

• Dr. Anis Koubâa
• Assistant Professor at CS Dept.
• Research Associate at ISEP/IPP-HURRAY! (Portugal)
• Email (Teaching) anis.koubaa.ccis_at_gmail.com
• Phone [phone]
• Background
• PhD from INPL/LORIA, Nancy (France)
• Master from UHP Nancy I (France)
• My Research
• Main Wireless Sensor Networks, Cyber-Physical
  Systems, Real-Time Embedded Systems,
  Quality-of-Service, Performance Evaluation
• Other Security

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Teaching Assistant

• Basmah Al-Soli
• Office no. 4034/8
• Office phone [phone]
• E-mail basmah.cs_at_gmail.com

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Texbook

• Tayfur Altiok, Benjamin Melamed,
• SIMULATION MODELING AND ANALYSIS WITH ARENA
• Hardbound, 456 pages,
• publication date JUN-2007ISBN-13
  978-0-12-370523-5ISBN-10 0-12-370523-1Imprint
  ACADEMIC PRESS

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Grading (may be changed)

• Grading Grades will be determined roughly as
  follows (Grading may be changed)
• One Mid-term, 20 total
• One Final Exam, 40 total
• Project, 20 total
• Lab Exams, 10
• Quizzes and Assignments, 10 total

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For more information

• Official course website
• http//www.aniskoubaa.net/ccis/cs433/
• All announcements will be posted on the website
• Interaction with students
• Mailing list
• ccis-cs433-spring2009_at_googlegroups.com
• To register
• http//groups.google.com/group/ccis-cs433-fall2009

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Goals of today

• Understand what is simulation and what is
  modelling
• Some applications of simulation and modelling
• What is the Life Cycle of the Modelling Process

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Some keywords to know

• System
• It is a collection of entities that act and
  interact together toward the accomplishment of
  some logical end (computer, network,
  communication systems, etc.)
• Simulation
• It is an experiment in a computer where the real
  system is replaced by the execution of the
  program
• It is a program that mimics (imitate) the
  behaviour of the real system

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Some keywords to know

• Model
• It is a simplification of the reality
• A (usually miniature) representation of
  something an example for imitation or emulation
• A model can be Analytical (Queuing Theory) or by
  Simulation.
• Performance evaluation (of a system)
• It means quantifying the service delivered by the
  System
• Experimental, Analytical, or by simulation

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Examples
Models of the system
Real System (Motherboard)
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Examples
Simulation models of the system
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Examples
Models of the System
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Example
Models of the System
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What is Simulation?

• ???? ?????????

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Why we need simulation?
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Applications of Simulation
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A few more applications
Flight Simulator
War gaming test strategies training
Transportation systems improved operations
urban planning
Games
Computer communication network protocol design
Parallel computer systems developing scalable
software
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Computer Simulation

• A Computer Simulation is a computer program
• that attempts to simulate an abstract model of a
  particular system.
• that describes the behavior of a real (physical)
  system and its evolution in time
• How it works?
• The behavior of the system is described by state
  variables
• The simulation program modifies the states
  variables to emulate the evolution

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Why Modeling and Simulation?
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Performance Evaluation

• ????? ??????

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Performance Metrics
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Performance Metrics

• The Performance Metric is a measurable quantity
  that precisely captures what we want to measure
  (response time, throughput, delay, etc.).
• For example, in computer systems, we might
  evaluate
• The response time of a processor to execute a
  given task.
• The execution time of two programs in a
  multi-processor machine.
• In network systems, we might evaluate
• The (maximum/average) delay experienced by a
  voice packet to reach the destination
• The throughput of the network
• The required bandwidth to avoid congestion

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What does affect the performance?

• The performance of a system is dramatically
  affected by the Workload.

• The Workload it characterizes the
• Quantity e.g. number of cars
• Nature type of cars (cars, trucks, motocycle,
  etc.)

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What does affect the performance?

• In the context of Web Servers, system inputs are
  http requests (GET or POST requests). The
  workload characterizes
• The intensity of the requests how many requests
  are received by the web server. High intensities
  deteriorate the performance.
• The nature of the requests the request can be
  simple GET request or a request that require the
  access of a remote database. The performance will
  be different for different request types.

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Benchmarks

• Benchmarks used to generate loads that is
  intended to mimic a typical user behaviour.
• Wikipedia definition
• In computing, a benchmark is the act of running a
  computer program, a set of programs, or other
  operations, in order to assess the relative
  performance of an object, normally by running a
  number of standard tests and trials against it.
• Benchmarking is usually associated with assessing
  performance characteristics of computer hardware
• Example the floating point operation performance
  of a CPU.
• Software benchmarks run against compilers or
  database management systems.