Network Performance

& Evaluation (NPE)

Junaid Qadir, Ph.D.

Today’s agenda:

What is Network Performance Evaluation

(NPE)?1

2 About this course: contents and resources

What is NPE?

1

ˉ Importance of Computer Networks

ˉ Importance of NPE

ˉ What does performance mean?

NPE (design, analysis and

evaluation)For a given packet arrival pattern and desired

performance (e.g., low packet drops), what

should be the size of router buffers? (design

question)

1

2 What is the quantitative improvement in

performance of the router after the latest

software (or hardware) upgrade? (analysis/

evaluation question)

Goals of NPE

Comparison of design alternatives1

2 System dimensioning

3 Relationship (causal/ correlational) modeling

4 Performance description in appropriate metrics.

About this course

2

Course Outline

45 lectures

Introduction to this course

(Lecture 1)

Today’s lecture

12 lectures

The Science and Art of NPE

Part A

Lecture 2-13

Module 1/3

Lecture 2-13

12 lectures

The Science of NPE

Statistical background (grammar of

science)

The Art of NPE

Part A12 lectures

The Science and Art of NPE

Part A12 lectures

The Science of NPE

The Science and Art of NPE

"The fundamental principle of science, the

definition almost, is this: the sole test of the

validity of any idea is experiment." -

Richard Feynman.

'In questions of science the authority of a

thousand is not worth the humble

reasoning of a single individual.' Galileo

Galilei.

The Science and Art of NPE

Part A12 lectures

Statistical background

It is better to be approximately right than be exactly wrong – John

Tukey

Part A12 lectures

The Art of NPE

The Science and Art of NPE

"Excellence in statistical graphics

consists of complex ideas

communicated with clarity, precision,

and efficiency." – Edward Tufte.

“All models are wrong; some are

useful." – George Box.

Part B

13 lectures

Lecture 14-26Lecture 2-13

Module 2/3

Empirical/ Experimental

NPE

Empirical/

experimental NPEPart B13 lectures

Lecture 14-26

Workload Modeling

Design of Experiments

Internet Measurement

Empirical/ Experimental NPE

Part B13 lectures

Workload Modeling

Empirical/ Experimental NPE

"The essence of modeling, as opposed to just

observing and recording, is one of abstraction.

This means two things: generalization and

simplification." - Dror Feitelson.

Part B13 lectures

Design of Experiments

Empirical/ Experimental NPE

Hypothesis testing is at the very core of the scientific method.

Does the „magic

tablet‟ work as

advertised or is it

just a gimmick?

Part B13 lectures

Internet Measurement

Empirical/ Experimental NPE

"Measure what is measurable, and make

measurable what is not so." - Galileo

Galilei

Part C

18 lectures

Lecture 27-44Lecture 14-26Lecture 2-13

Module 3/3

Simulation/ Modeling based

NPE

Part C

Simulation/ Modeling based NPE

18 lectures

Lecture 27-44

Probability and Stochastic Processes

Preliminaries

Analytical Modeling

Simulation Modeling

Part C18 lectures

Stochastic Background

Simulation/ Modeling based NPE

PROBABILITY

RANDOM VARIABLE’S VALUE

Part C18 lectures

Analytical Modeling

Simulation/ Modeling based NPE

ROUTER

PACKET

"The essence of modeling is one of abstraction.

This means two things: generalization and

simplification."

QUEUE

SERVER

Part C18 lectures

Simulation Modeling

Simulation/ Modeling based NPE

Computer based simulation modeling can be performed when

experimenting with real system is not practical or efficient and when

simpler analytical methods do not exist

Summary of this course

(Lecture 45)

Lecture 27-44Lecture 14-26Lecture 2-13

Course conclusion

Course textbook

Course guidebook

Course companion site

http://vulms.vu.edu.pk

Course companion site

http://sites.google.com/site/netperfeval

Reference for today’s lecture

Chapter 1 [Raj Jain]

Find more lecture resources at the course‟s companion site:

http://sites.google.com/site/netperfeval

Books

Raj Jain, “The Art of Computer Systems Performance Analysis”

Figures and Images:

Credits/ Acknowledgments

Car Crash: http://www.pclaunches.com/other_stuff/audi_uses_supercomputer_for_crash_simulations.php

Galileo‟s Portrait: http://en.wikipedia.org/wiki/File:Justus_Sustermans_-_Portrait_of_Galileo_Galilei,_1636.jpg

George Box‟s Picture: http://gallery.socionix.com/d/49618-2/1990_George_Box.jpg

VU LMS: http://vulms.vu.edu.pk

Edward Tufte‟s Picture: http://www.freebase.com/view/en/envisioning_information

Clipart supplied with Microsoft Office

These resources have been used in these lecture slides for educational purpose under the fair use doctrine.

The ownership of these resources, if copyrighted, is retained by their respective copyright owners.

[ end of lecture ]