proposal for m sc project networks and distributed systems

UNIVERSITY OF NAIROBI

An Empirical Study and Simulation of Wireless VoIP in Areas that are

Geographically ChallengedNetwork Performance and Distributed

Computing

Kenneth Odhiambo ‐ P58/70655/2008Supervisor: Theuri

3/21/2010

Study Programme: Masters in Computer Science (MSc. CS)

This Document outlines my MSc. Dissertation Project Proposal, the purpose of which is to propose a solution that will incorporate a people excluded from the cellular network as a result of geographical challenges. The study will attempt to report the viability of Wireless VoIP in geographically challenged areas, through an empirical study and simulation to address areas related to performance in a wireless environment.

1 | P a g e CONTACT: 0733-999235;; [email protected]

Table of Contents

Contents 1. Introduction ....................................................................................................................... 2

1.1. Problem description ....................................................................................................... 2

1.2. Objective .......................................................................................................................... 3

1.3. Importance of Study (to the MSc. CS) ............................................................................ 3

1.4. Scope of Study: ................................................................................................................ 4

2. Literature Review ............................................................................................................... 5

3. Methodology ....................................................................................................................... 7

4. Resources Required ............................................................................................................ 8

4.1. Software Components..................................................................................................... 8

4.2. Hardware Resources ...................................................................................................... 8

4.3. Other Resources .............................................................................................................. 8

5. Time Schedule ..................................................................................................................... 9

6. Bibliography ..................................................................................................................... 10


1. Introduction

The most prevalent and successful wireless technologies are all cellular. Cellular carriers are

scrambling to provide fast, efficient IP transport mechanisms across the various cellular

networks. But therein lies a lot of the problem. With wireless technology, challenges are

often about finding a line of sight — a clear path from the office or transmitter beaming out

the internet signal to the home or business receiving it. Thus, forested areas, mountainous

regions and remote villages will most certainly be overlooked by cellular carriers, given that

these kinds of terrain require several towers to be setup and this is simply not cost‐effective

for most cellular carriers. Cellular carriers thrive on high demand for voice services which

usually have a high cost of deployment.

Fixed wireless VoIP is cheaper to deploy and has much higher data capacity but the end‐user

device (usually a computer) is more expensive than a cellphone. These not withstanding,

wireless devices are experiencing a plummet in prices globally; this is also reflected in the

local market. A key point to note is that once connectivity has been brought to a reasonable

distance then it can be spread to the challenged area by setting up a Wi‐Fi VoIP mesh

network. Creating a local community wireless network can be done quickly using off‐the‐

shelf components. The real challenge is to build enough demand to make such a network

financially sustainable. The best way to do this is through telephony. A considerable latent

demand for person‐to‐person communication already exists, and phones are easy to use,

have low maintenance and support costs, and can support a wide range of voice based and

data services.

Therefore, this study will assess the use of wireless VoIP technologies for promoting

telecommunication development and applications in the geographically challenged areas.

1.1. Problem description

The country of Kenya boasts some 39 million people (as of the recent census – not yet

confirmed) living in an area spanning 582,650 sq km with the rift valley as one of the major

land marks, deserts to the north, forests and mountainous in the central and western part of

the country and a few islands in the Coastal and Nyanza provinces. With the country’s sheer

size, come the inevitable geographical challenges of deploying microwave technology


successfully. With microwave being the de facto connectivity method in Kenya, We are

forced to deal with the challenges that it brings such as susceptibility to a number of factors

that lead to signal degradation and eventually loss of that signal consequently we get a

communication breakdown. Some of these factors include signal attenuation over distance,

lack of line of sight (LoS), noise addition to the signal etc. Thus, Although Kenya has an

expansive microwave network, in certain areas communication is still a problem. The

microwave network is mainly used for voice communication, with data coming of age slowly.

Only 1 in 400 Kenyans have regular Internet access despite the plunging costs of connectivity,

yet Voice over IP (VoIP) has been touted as a significantly lower‐cost communication media.

With these in mind, we want to look at how communication can be delivered to

geographically challenged areas that cellular providers overlook while taking into

consideration challenges such as performance, quality of service, and resource optimization

of VoIP.

1.2. Objective The main objective is to study and document ways of delivering wireless VoIP to

geographically challenged areas at lower costs while maintaining high performance,

Other objectives include

1. To determine the quality of service offered by wireless VoIP in geographically

challenged areas

2. Simulate a Wireless VoIP Network with focus on Reliability and suggest ways of

addressing the resultant problems

3. To report the finding of the study and simulations

1.3. Importance of Study (to the MSc. CS)

VoIP is a rapidly evolving technology that could possibly revolutionize the

telecommunication industry. When implemented on wireless data networks, VoIP could

prove to be instrumental in the convergence of existing fixed and cellular telephony

networks with the fast growing wired and wireless data networks. Capacity and Quality of

Service are two of the most important issues that need to be resolved before the

commercial deployment of wireless VoIP.


1.4. Scope of Study:

The study focuses on the quality of VoIP in wireless networks with mobile devices both in lab

and live network environment setups by conducting a methodic performance analysis.

Likewise, our study will encompass the signaling performance required for VoIP applications.

We will evaluate VoIP quality and signaling performance in non challenged environment. The

Session initiation protocol (SIP) will be the selected protocol for use during experimentation.

The Study will be conducted in Nairobi area in the following selected areas;

Kileleshwa Estate – A highly vegetative area with new high‐rise buildings springing up.

Kiserean Region, ‐ A hilly suburb with sparsely populated settlements

Nairobi Dam – This area will represent regions with larges quantities of water bodies

Our study takes into consideration both the performance of the network and also the

performance of real embedded VoIP clients. In addition, we validate the results, by

comparing them to the actual performance in areas with clear lines of sight from the service

providers within the Nairobi Region. Based on the results, we analyze the primary

differences in performance between simulations found in the literature, our lab experiences

and a live network case study. Finally, we discuss possible features that can improve the

performance enough in current and future releases to support Wireless VoIP in

geographically challenged areas.


2. Literature Review

An extensive research on the area under discussion will be reviewed, this will feature major

literatures on Wireless mesh networks, VoIP and the surrounding technologies Also best

practices and guidelines used in the networking projects are reviewed. Some of the

indicative literature review is given below:

1. Corinna “Elektra” Achele et al, Wireless Networking in the Developing World, first

Edition, Limehouse Book Sprint Team, 2006

This book looks at a practical introduction to radio physics with details on how a

wireless infrastructure can be built for very little cost compared to traditional wired

alternatives. Light is shed on where waves emanating from device are going, what

happens when they bounce off objects and how they can be used in the same area

without interfering with each other. It examines the intricacies of antennas and

transmission lines receiving signals and passing them to the receiver with minimum

amount of distortion for decoding.

2. Paul J. Fong et al, Configuring Voice over IP, Second edition, Syngress Publishing,

Inc. 800 Hingham Street Rockland, MA 02370, USA, 2002.

To truly add value to wireless VoIP, it is imperative that information relating to new

technologies is taken into account, with coverage of topics such as Session Initiation

Protocol (SIP) and Media Gateway Control Protocol (MGCP). VoIP networks are

required to interconnect in some manner with a traditional voice network, such as to

the public switched telephone network. An understanding of traditional voice‐

networking technology is also invaluable because the historic aspects of voice

networking provide an insight into why certain VoIP protocols are designed and

operate the way they do. After all, there would be no VoIP without traditional voice!

This book offers a review of the available QoS techniques, it also provides actual

configurations of ways to implement several techniques to maintain and improve

voice quality. Finally, this literature will provide guidance that is required to

understand, design, deploy, and maintain VoIP networks.


3. Dr.Ghossoon M.Waleed Al‐Saadoon, “Asterisk Open Source to Implement Voice

over Internet Protocol”, IJCSNS International Journal of Computer Science and

Network Security, VOL.9 No.6, June 2009

This journal provides a procedural approach to building a VoIP network. In order to

be able to simulate a Wireless VoIP network, an understanding of the following will

be important:

1. Setup a server that provides VoIP using Asterisk.

2. Determine the advantages of using VoIP.

3. Check the difference of Asterisk over other type of VoIP server.

4. Study the differences between H.323 protocol and Session Initiation protocol (SIP).

4. The Easy Guide to Data and Voice Networking, Cisco Systems Ltd. The Square

Stockley Park Uxbridge Middlesex UB11 1BN


3. Methodology

To achieve the objectives the project will provide extensive theoretical analysis to be done

to the wireless VoIP system such as the protocols in use, latencies that are experienced while

in use, the capacity that can be handled by the wireless links under extraneous conditions.

As alluded to in the scope, the “challenged” locations are defined by many factors including:

Heavy vegetation, bad weather such as fog, mountainous regions, and areas with large

water bodies etc. Each factor must be properly weighted for importance. Additionally,

because there are so many variables that must be taken into account it will most likely be

impossible to gather all of them from one data source. Thus a major challenge is data

integration.

The Second Stage will include the use of a simulator to study the performance of the

wireless VoIP systems with the selected area. NS3 software will be used to accomplish this

work. A software simulation is important since it normally considers all practical factors

which may be too general to be considered in the theoretical development. The system

parameters will be varied or changed in order to study their effect on the system’s

performance. The parameters used are:

Reliability Mean time to failure (MTTF)

Mean time to repair (MTTR)

Mean time between failures (MTBF)

Percentage of time available

Packet loss rate

Bit error rate

Based on both the theoretical and simulative studies carried out, we shall then document

the results and draw conclusions as to the feasibility of the W‐VoIP in geographically

challenged areas.


4. Resources Required

4.1. Software Components

Asterisk – Free Open Source Tool

Open source software PBX system.

Asterisk gives us connectivity for both PSTN and VoIP networks.

Provides channels for communication on different hardware’s, protocols (SIP), and codec’s.

Yate – Free Open Source Tool

Yate is an open source soft phone which can be used as VoIP client.

Yate provides many modules like ‘callgen’, and ‘message sniffer’ for measuring the performance of the PBX server.

NS3 – Free Open Source Tool To ensure the validity of the results and to extend the results in areas like node mobility we will simulate an access point based wireless network using the Network Simulator (NS2 or NS3). NS2 is a discrete event simulator meant for networking research

4.2. Hardware Resources

Wireless IP Phones – Estimate Price: Kes 1000/=

Active analog Phone ‐ Estimate Price: Kes 1,000/=

GSM Smart Phones with Symbian OS Installed ‐ Estimate Price: Kes 15,000/=

Linksys SPA3102 – Gateway ‐ Estimate Price: Kes 8,000/=

Linksys ATA – Adapter ‐ Estimate Price: Kes 8,000/=

PC ‐ Estimate Price: Kes 10,000/=

4.3. Other Resources

Travel Expenses ‐ Estimate Price: Kes 10,000/=

Documentation – Estimate Price: Kes 5,000/=

Supervisory (72,000/=)

Total Budget expenditure: Estimate Price: Kes: 58,000/=


5. Time Schedule

The final section of this proposal identifies the anticipated workflow of my project along with

expected completion dates. Each phase will have some overlap from other phases. For

example, writing will take place during all phases although for illustrative purposes they are

each listed as disjoint. I have given extensive consideration to the amount of work required

to complete this project and have determined that although difficult this project can be

completed in the allotted time. This can be seen in the summary table directly below

Milestone Estimated Time of Completion

Analyze the project and do literary

review

Define the problem and write

research proposal

Gather data sources

Design schema

Integrate sources

Design Simulation/experiment

Run Simulation/experiments

Gather results

Complete dissertation paper

‐March 1st

‐March 24th

June 10th

July 15th

July 20th

July 25th

August 15th

September 1st

October 1st to 15th


6. Bibliography

i. Dr.Ghossoon M.Waleed Al‐Saadoon, “Asterisk Open Source to Implement Voice over

Internet Protocol”, IJCSNS International Journal of Computer Science and Network

Security, VOL.9 No.6, June 2009

ii. Paul J. Fong et al, Configuring Voice over IP, Second edition, Syngress Publishing, Inc.

800 Hingham Street Rockland, MA 02370, USA, 2002.

iii. Corinna “Elektra” Achele et al, Wireless Networking in the Developing World, first

Edition, Limehouse Book Sprint Team, 2006

iv. Steven M. Ross (The University of Memphis) and Gary R. Morrison (Wayne State

University), experimental research methods,

v. A. Al‐Naamany, H. Bourdoucen and W. Al‐Menthari, Modeling and Simulation of

Quality of Service in VoIP Wireless LAN, Journal of Computing and Information

Technology ‐ CIT 16, 2008, 2, Pages 131–142.

vi. WIKIPEDIA, Voice over IP. Article from Wikipedia, December 2009. (Available on:

http://en.wikipedia.org/wiki/VoIP ).

vii. R. Price, S. Manor, C. Bormann, T. Bremen, J. Christoffersson, H. Hannu, Z. Liu, and J.

Rosenberg, Signaling Compression (SigComp). RFC 3320, January 2003. [Online].

Available: http://www.rfc‐editor.org/rfc/rfc3320.txt

viii. Professor Aduda’s Lecture Notes on Research Methodologies

ix. T. J. Patel, V. A. Ogale and S. Baek, N. Cui, R. Park, Capacity Estimation of VOIP

Channels on Wireless Networks, WNCG, Dept of Electrical and Computer Engineering,

The University of Texas at Austin, Austin TX 78712

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