i

PERFORMANCE ANALYSIS OF OLSR PROTOCOL IN MANET

CONSIDERING DIFFERENT MOBILITY SPEED AND NETWORK

DENSITY

KOAY YONG CETT

BACHELOR OF COMPUTER SCIENCE (COMPUTER NETWOR

SECURITY) WITH HONOURS FACULTY OF INFORMATICS AND

COMPUTING UNIVERSITY SULTAN ZAINAL ABIDIN

2019

i

DECLARATION

I declare that the project report entitled Quality Analysis of the OLSR Protocol in

MANET Considering Different Mobility Speed and Network Density is based on the

results of my own investigations using information from knowledgeable sources with

the exception of quotations and quotations properly acknowledged. I also claim that no

student of the University of Sultan Zainal Abidin has previously submitted it.

Signature: ………………………

Name: Koay Yong Cett

Date:

ii

APPROVAL

This project report, entitled Performance Analysis of OLSR Protocol in MANET

Considering Different Mobility Speed and Network Density, was prepared and

presented by Koay Yong Cett (Matric Number: BTBL17046228) and found acceptable

in terms of content, quality and partial compliance with the Bachelor's degree in

Computer Science (Network Security) requirement in University of Sultan Zainal

Abidin.

Signature: ………………………………

Supervisor: Dr. Nor Aida Binti Mahiddin

Date:

iii

ACKNOWLEDGEMENT

First and foremost, I am grateful to my beloved God for blessing me and encouraging

me to finish the OLSR Protocol Performance Analysis this final year in MANET

Considering Different Movement Speed and Network Density study. I would also like

to convey my gratitude and appreciation to my lecturer, Dr. Nor Aida Binti Mahiddin,

for giving me a chance to do work and lead me through study and project experience. I

was profoundly influenced by her passion, honesty, and inspiration. She showed me

how to carry out the research and explain the conclusions of the study as nicely as

possible. Under his leadership, it was a great privilege and joy to be supervised. I am

also extremely indebted to my parents for their determination, encouragement, care and

willingness to educate and prepare me for my coming years. I would also like to thank

my classmates for the encouragement, support and feedback that I have provided

throughout this process.

Lastly, I am very much thankful to the Faculty of Informatics and Computing for the

chance given to me to explore and discover new knowledge. I would really like to thank

all the lecturer for aiding me with assistance and guidance to complete the project for

the final year.

iv

ABSTRAK

Rangkaian Ad Hoc Mudah Alih (MANET) merupakan rangkaian yang dicipta secara

dinamik oleh banyak nodyang bebas atau autonomi yang disambungkan melalui

sambungan tanpa wayar. MANET adalah rangkaian ad hoc mudah alih dan tidak

bergantung kepada infrastruktur yang sedia ada seperti router di rangkaian berwayar

atau titik akses dalam rangkaian tanpa wayar. Nod mudah alih dalam rangkaian ini

bergerak secara rawak dan topologi sering berubah. Protokol routing MANET

memainkan peranan penting untuk memastikan komunikasi yang boleh dipercayai dan

stabil antara nod mudah alih. Dalam routing MANET, protokol menggambarkan

komunikasi antara nod mudah alih dan mendorong mereka untuk memilih laluan yang

terbaik antara sumber dan destinasi. Pada umumnya, terdapat 3 jenis protokol

penghalaan: proaktif, reaktif dan hibrid. Projek ini akan memberi tumpuan kepada

OLSR yang merupakan protokol penghalaan proaktif. OLSR ialah ‘optimized link- state

routing protocol’ di mana penyebaran paket dalam rangkaian dilakukan dengan teknik

relasi pelbagai titik (MPR). Kertas kerja ini menilai prestasi protokol pelayaran OLSR

pada kelajuan mobiliti dan ketumpatan rangkaian yang berbeza. Metrik prestasi yang

dipertimbangkan dalam kajian ini diukur berdasarkan keupayaan purata, nisbah

penghantaran paket dan kelewatan purata. Simulator Rangkaian (NS) versi 2.35 dan

patch luaran UM-OLSR digunakan untuk merangsang dan menilai prestasi protokol

OLSR.

v

ABSTRACT

Mobile Ad Hoc Network (MANET) is generated by an autonomous mobile node

network linked via wireless links in a dynamic manner. MANET is a network of self-

organization and does not relied on pre-existing infrastructure including the wired

network routers or wireless network access points. The mobile nodes in this network

are shifting randomly, and topology is often evolving. MANET routing protocols play

a vital role in making connectivity between mobile nodes reliable and stable Protocols

logically conclude interaction between mobile nodes in MANET routing and urge them

to pick the best pathway between origin and destination. There are 3 types of routing

protocols are generally available: constructive, reactive and hybrid. This project will

focus on OLSR which is a proactive routing protocol. OLSR defined as an optimized

version link state routing where the diffusion of packet in the network is performed with

multi point relay (MPR) technique. This paper examines OLSR routing protocol

performance on varying speed of mobility and network density. The performance

metrics considered in this study is measured based on average throughput, packet

delivery ratio and average delay. Network Simulator (NS) version 2.35 and external

patch UM-OLSR is utilised to stimulate and test the performance of OLSR protocols.

vi

CONTENTS

DECLARATION ........................................................................................................... i

APPROVAL ................................................................................................................. ii

ACKNOWLEDGEMENT .......................................................................................... iii

ABSTRAK ................................................................................................................... iv

ABSTRACT .................................................................................................................. v

CONTENTS ................................................................................................................. vi

LIST OF TABLES .................................................................................................... viii

LIST OF FIGURES .................................................................................................... ix

LIST OF ABBREVIATIONS ..................................................................................... x

LIST OF APPENDICES ............................................................................................ xi

CHAPTER 1 ................................................................................................................. 1

INTRODUCTION ........................................................................................................ 1

1.1 Background ......................................................................................................... 1

1.1.1 Mobile ad hoc network (MANET) ............................................................. 1

1.1.2 Classification of the Routing Protocols ................................................ 3

1.1.3 Optimized Link State Routing (OLSR) Protocol ................................ 5

1.2 Problem Statement ........................................................................................ 9

1.3 Objectives ....................................................................................................... 9

1.4 Scopes ........................................................................................................... 10

1.5 Limitation of Works .................................................................................... 10

1.6 Summary ...................................................................................................... 11

CHAPTER 2 ............................................................................................................... 12

LITERATURE REVIEW ......................................................................................... 12

2.1 Introduction ...................................................................................................... 12

2.2 Related Works .................................................................................................. 13

2.3 Summary ........................................................................................................... 19

CHAPTER 3 ............................................................................................................... 20

METHODOLOGY .................................................................................................... 20

3.1 Introduction ...................................................................................................... 20

3.2 Research of Methodology ................................................................................ 20

3.3 Simulation ......................................................................................................... 22

3.4 Project Framework .......................................................................................... 24

3.5 Project Flowchart of the Route Selection Technique .................................... 27

vii

REFERENCES ........................................................................................................... 29

APPENDIX ................................................................................................................. 32

viii

LIST OF TABLES

TABLE TITLE PAGE

2.1 Comparison of Parameter Metrics 13

3.1 Comparison of Network Simulator 22

3.2 Table in the cache of the nodes 26

ix

LIST OF FIGURES

FIGURE TITLE PAGE

1.1 Classification of Routing Protocol in MANET 3

1.2 Hello Message Format 6

1.3 Format of an OLSR Packet 6

1.4 Classical Flooding and Flooding with MPR 8

3.1 Research Methodology 21

3.2 NS2.35 installed in Ubuntu 16.04 23

3.3 UM-OLSR is patched into NS2.35 23

3.4 Framework of OLSR Routing Protocol 24

3.5 Routing Selection Technique (MPR) 27

x

LIST OF ABBREVIATIONS

MANET Mobile Ad-Hoc Network

OLSR Optimized Link State Routing

AODV Ad-Hoc On-Demand Distance Vector

TORA Temporally Ordered Routing Algorithm

ZRP Zone Routing Protocol

DSR Dynamic Source Routing

DSDV Destination-Sequenced Distance-Vector

GRP Gathering based Routing Protocol

GPSR Greedy Perimeter Stateless Routing

xi

LIST OF APPENDICES

APPENDIX TITLE PAGE

1 Gantt Chart 1: Activities and milestones FYP1 32

1

CHAPTER 1

INTRODUCTION

1.1 Background

1.1.1 Mobile ad hoc network (MANET)

The term MANET originate from the name of an Internet engineering task force

(IETF) work group founded in 1998 with the purpose of standardizing the routing

protocols based on Internet protocol technology for ad hoc networks, mobile, etc.

MANET can be described as a wireless network that is self-organized and self-

configured. It is dynamically generated by an autonomous system of mobile nodes

linked by wireless connections that can be implemented without any external

infrastructure support or centralized administration like centralized base station (BS) or

access point (AP). It is a temporary network that is able to setup anytime and anywhere

as an alternative way for the situation where the infrastructure is poor and insufficient.

For instance, MANET is the primarily selected network to be used in disastrous areas

that could have destroyed existing and local infrastructure, causing a huge breakdown

in communication.

2

MANET essentially consists of multiple nodes or computers like tablets, cell

phones and video cameras. All of these machines are linked so that they can

communicate with each other via a wireless connection. In addition, All MANET

mobile nodes may connect or leave the network at any time without any limitations or

requirements. Then the nodes able to move randomly and organize themselves. Thus,

the network's topology may change vigorously and unforeseeable. Besides, each

network node can be used as a recipient, transmitter or intermediate node that functions

as a router that transmits data to other mobile nodes. The nodes are highly mobile in

real situations and rely on batteries to function depending on the MANET application

types [1].

Routing protocols are required in routing, a method of conveying information

across the network from a point of origin to the exact destination. The routing in

MANET is based on a easy approach that allow the re-emission of the data message by

each node for the ease of propagation within network. The key issues of routing protocol

lie in the choice of the best pathway. To find the correct route between two or mode

nodes in the network, the routing protocols are used. In a specific manner, these

protocols help nodes to make decision on finding the optimal path to route the packets

in network. It is also used to create and sustain an up-to-date routing table that allows

the node to choose the optimal route between the origin node and the target node for

communication. A few routing protocols were suggested to address the problems of

highly mobile nodes and frequent topology shifts in the MANET network [2].

3

1.1.2 Classification of the Routing Protocols

Figure 1.1: Classification of Routing Protocols In MANET

Classification of Routing Protocols is divided into 3 types:

I. Proactive Protocols

It is also defined as table-driven protocols which uses mapping tables to retain

any node's route and path in the network. This builds the network's routing protocols by

constantly sending out the topological information data packets to each node in the

4

network. Thus, with the newest routing information, the routing information of each

node is updated regularly. When new nodes are attached or removed from the network,

control messages are sent to neighbouring nodes and routing tables are modified. This

type of protocol typically utilizes link state algorithms that flood the network with

details about their neighbours [3].

II. Reactive Protocols

It is also called on-demand protocols and initiates a path exploration mechanism

only when the origin node has the information packets to be transmitted to the

destination to find the path between the communicating nodes. Once the path is

established, route maintenance will be done to maintain this route until it is no longer

necessary or the data packets arrive at the destination node. Series of action have been

taken to maintain the new route and avoid any looping such as a sequence number is

used [3].

III. Hybrid Protocols

It is a derivative of the approach of mixing proactive and reactive protocol. It

provides some benefits of both the above listed protocols by establishing an immediate

reactive vicinity up to a certain distance that is interconnected with the proactive

connections. A reactive scan is activated if an application needs to send packets to a

node outside this region. With this, the routes in the coverage zone of a node are

available immediately. Initially, the routing tables are used as proactive routing

protocols with the root nodes. If the node found that no data about the pathway to the

5

destination of origin node, pathway detection is initiated as reactive routing protocols

[4].

1.1.3 Optimized Link State Routing (OLSR) Protocol

OLSR is the equivalent implementation of the routing protocol for the classical

link-state. In contrast to the distance vector routing protocol, this routing protocols are

not subjected to routing loops and have no issues in term of scalability [3]. The

transmission of topological information between nodes leads to the creation of a

significant amount of traffic due to the flooding mechanism of the classical connection

state routing protocols. It is undesirable attribute of the MANET due to inadequate

resources. New procedure is implemented by the OLSR in the network to reduce the

volume of traffic involved. All nodes of OLSR are allowed to receive the data packet

of the topological information and only minimum number of nodes known as Multipoint

Relays (MPRs) are able to transmit the messages across the network. MPRs of certain

node are minimum number of its neighbour that are necessary to communicate will all

its other neighbours within two hops [7]. Thus, it guarantees the data messages of

topological information of network will be received by every node in network.

Two principal mechanism is found in OLSR protocol which is neighbourhood

detection and one for topology management. For this mechanism, 4 types of control

messages used are HELLO, TC, MID, and HNA [1]. Neighbour sensing is performed

by using HELLO packets. It has 3 different function in OLSR protocol. The messages

are sent to its neighbours at one hop and two hops. In addition, it is also used in the

declaration of local node as MPRs. [5] The HELLO message format is shown in Figure

2. The HELLO message is also part of the body of OLSR message that are shown in

6

Figure3. The HELLO data packet is sent in data field of OLSR packet with Message

Type and TTL both set at 1.

Figure 1.2: HELLO message format [9].

Figure 1.3: Format of an OLSR packet [9].

7

The dissemination of topological packet is performed by the spreading of TC

packets using optimized diffusion or MPRs. The TC message packet contain a list of

links in the neighbourhood of node in the network [6]. The OLSR protocol also take

into the consideration of all interfaces that are linked to the node with MID messages.

Thus, the nodes are able to use all available routes independent of the type of each hop

in an efficient way. One of the interface addresses in the network will be chosen to be

the main address and uses as a reference in control messages. Furthermore, HNA

messages are used for the declaration of subnetworks and host outside of MANET. The

subnetworks and hosts are made reachable by a node acting as a gateway [1].

The main goal of MPRs is to lower down the number of redundant or unneeded

transmission during the normal diffusion of the message. MPRs is specifically useful in

the transmission of control messages over the network. The classical diffusion

mechanism applied in link state protocol is optimized by the MPRs. A group of MPRs

is selected by a given node based on the knowledge of the neighbourhood at two hops.

In MANET network with topology that changes in a random manner, the MPRs needed

to be recalculated every time the two-hop neighbour set experience changes. For this

reason, the status of MPRs is set for a limited period in the neighbourhood [8]. The

improvement in diffusion methods of the packets with MPR technique is shown in the

Figure 4. In the first part of the diagram, central node diffuses the control packets to

eight other nodes using the classical the classical flooding technique. On the next

illustration, the relay technique is used and four nodes is selected to relay the message.

Thus, With the choice of MPRs, the number of unnecessary transmissions is minimized.

8

Figure 1.4: Classical flooding and Flooding with MPR technique [1].

9

1.2 Problem Statements

The nodes relocate in an arbitrary and unpredictive way due to the multi-hop

behaviour of ad hoc networks. This non-specific and volatile node motion causes the

connection to split and reform continuously. The performance of the mobile ad hoc

network is depending on the interconnection between any two nodes transferring the

message that contain the topological information. The mobility speed and network

density of the nodes mat affect the duration required to forward the messages from its

source to destination. Thus, it is important to utilise the routing protocol so that the

nodes in the network can maintain the information packet needed for transferring

packets from source to destination.

1.3 Objectives

The main goal of this thesis is to solve the problem statement proposed by

analyse the effect of different mobility speed and network density. Thus, this project is

mainly focus on the following objectives:

o To study the OLSR in MANET.

o To apply the OLSR routing protocol in MANET by using NS2 stimulation tools.

o To analyse and evaluate the performance of OLSR by using different node

mobility speed and network density.

10

1.4 Scopes

The scope in this thesis is to evaluate the performance of OLSR routing protocol

in MANET environment. In addition, the other scope is to study the simulation tools

needed for this routing protocols.

1.5 Limitation of Works

The MANET could not be implemented in real-life experiment because:

1. Costly

The coverage area for the application of MANET such as in a disastrous

environment is large. Then, the amount of labour and mobile devices needed for the

network is very high. Thus, the expenditures for setting up the real-world environment

for MANET will be enormous.

2. Time for configuration is long

The configuration of MANET in real world is time consuming due to the

coverage area required is wide. For instance, disaster area like tsunami is huge and it

will take a few days to set up and build this environment for real-life simulation.

11

1.6 Summary

This chapter covered the context, MANET presentation, problem statement,

project goal, scale and limitation. Because of the existence of MANET, it is promising

in terms of education to establish this research project as a commitment to MANET's

field.

12

CHAPTER 2

LITERATURE REVIEW

2.1 Introduction

In this chapter, few research papers related to the project are selected as a

literature review. Data and information are collected to give a better view of how the

process works and how it benefits from the project.

As described in chapter 1, it is understandably stated about the definition of

routing protocol in MANET. In the multi hop nature of MANET, the nodes

communicate with each other node using the wireless link. Every node can be viewed

as a host as well as a router that transmits topological information data packets to other

nodes in the network. The foremost difficulty in the application of multi hop mobile ad

hoc networks is the evolution of the routing protocol that can perform best in finding

pathway between the origin and targeted destination in MANET. Since MANET is less

a network system and the nodes are constantly breaking and rebuilding, its existence

makes it difficult to control the network. The implementation of the routing protocol is

therefore used to boost the MANET's performance.

13

2.2 Related Works

Figure 2.1: Comparison of Metrics Parameter.

Ad hoc routing protocol is considered as the convention and typical term to

describe the protocol that help to make the decision on which paths to route the packets

between the source and destination of computing devices in MANET. In ad hoc

networks, nodes do not possess the knowledge about the topology of their networks.

Due to the nature of limited resources and random movement of nodes, routing can be

a problem in MANET. Thus, routing protocol is proposed to solve the situation and find

the optimal pathway from the origin to target node.

In a research paper “Performance Analysis of AODV, OLSR and GPSR

MANET Routing Protocols with Respect to Network Size and Density” [10] from

Muthana Najim Abdulleh and Salman Yussof. In this paper, they perform a routing

protocol evaluation comparison with the specific number of nodes and the grid size of

the stimulated area. Routing protocol assessment was conducted by network simulation

14

and efficiency is defined in terms of throughput, average end-to-end delay, packet

delivery fraction and normalized routing load. The stimulation is executed for 2

scenarios and the differences between these 2 scenarios was in term of stimulation

parameter examined. They set the number of nodes for the simulation in the first

example at 30, 50, 70, 90, 110, 130, 150 nodes. In the second scenario, they focus on

the network density and set the map size into 500×500, 750×750, 1000×1000,

1250×1250, 1500×1500 and 1750×1750 in term of metre. The result from the

simulation shows that GPSR outperform OLSR and AODV in the most of the tests.

Furthermore, the simulation findings also demonstrate that the increase in the number

of nodes influences the normalized routing load, while the change in the map scale of

the stimulated region has a significant effect on throughput, end-to-end delay and packet

delivery fraction.

In a research paper from K.Natarajan and G.Mahadevan titled “Mobility based

Performance Analysis of MANET Routing Protocols” [11] make a performance

analysis on how the speed in mobility can influence the routing performance of

protocols. The routing protocols that chosen for the performance analysis is Ad hoc on

demand distance vector routing (AODV), Destination Sequenced Distance Vector

(DSDV), Dynamic Source Routing (DSR), Location-Aided Routing (LAR), Optimised

Link State Routing Protocol (OLSR), Fisheye State Routing (FSR) and Zone Routing

Protocol (ZRP). The network stimulation is split into 3 different scenario which is low

mobility where node speed is 10m/s to 15m/s, medium mobility with node speed is set

to 15m/s to 20m/s and high mobility where node speed is 20m/s to 30m/s. The pause

time is kept constant at 10s. The simulation outcome reveals that LAR and AODV work

better than other protocols, where both transmit approximately 50 to 60 percent data

15

packets, regardless of speed, successfully. Besides, the DSR shows that 53% and 95%

higher delay than AODV and DSDV protocols.

In addition to that, Lakshman Naik L, R. U. Khan and R. B. Mishra in “Analysis

of Node Velocity Effects in MANET Routing Protocols using Network Simulator

(NS3)” [7] analysed the performance of various ad hoc routing protocols with different

node speed. The purpose of this paper is to discuss the effect of mobility speed of the

nodes on different routing protocol. The routing protocol that are chosen for the

performance analysis is AODV, DSDR and OLSR. They run the network simulation

with 3 different node speed which is 10m/s, 20m/s and 30m/s. The simulation has been

carried out by keeping 10 number of source/sink connections fixed. As for the result,

the throughput of the OLSR protocol is high as compared to AODV and DSDV during

node speed variation. Although OLSR has a slight degradation as node speed increases

but it is still better comparing to AODV and DSDV. In addition, packet delivery ratio

of OLSR is higher when comparing to AODV and DSDV. However, OLSR slightly

degrades as node speed increases. In End to end delay, the performance of OLSR is

superior when comparing to the AODV and DSDV. However, OLSR also experience a

slightly degradation as node speed increases. Moreover, the packet loss results reveal

that the performance of OLSR is better than AODV and DSDV, but it slightly degrades

as node speed increases. Lastly, they infer that performance of OLSR is better when it

is compared to AODV and DSDV in all the metrics they analysed.

16

On other hand, Gouri M. Patil, Ajay Kumar and A. D. Shaligram in

“Performance Comparison of MANET Routing Protocols (OLSR, AODV, DSR, GRP

and TORA) Considering Different Network Area Size” [12] make a comparative

performance analysis of various ad hoc routing protocol by considering different

network area size. The routing protocols that have been evaluated are OLSR, AODV,

DSR, GRP (Gathering based Routing Protocol) and TORA (Temporally Ordered

Routing Algorithm). The simulation of the various routing protocol is performed for

network area size of 500 X 500 square meters, 1000 X 1000 square meters and 2000 X

2000 square meters with 50 number of nodes is kept consistent. The results show that

the TORA is the best choice when network load is an important factor. The DSR is the

second-best choice continued with AODV, OLSR and GRP for extensible network area

size up to 2000x2000 square meters. Besides, if end-to-end is important factor in the

application scenario, the GRP provides better performance if network area size is up to

1000 x1000 square meters. While, OLSR is the first choice for 2000x2000 squares

meters. In addition, AODV have the maximum throughput in 3 scenarios with different

network area size.

This recent paper by D. Kumar and S.C. Gupta had conducted “Transmission

Range, Density & Speed based Performance Analysis of Ad Hoc Networks” [13]. The

purpose of this paper is to study the effect of various transmission range, node density

and speed on three routing protocols which is OLSR (proactive), DSR (reactive) and

ZRP (hybrid). These 3 routing protocols represent the three groups in the mobile ad hoc

network which is proactive, reactive and hybrid routing protocols respectively. The

network simulation is executed based on 3 scenarios in term of node density,

transmission range and node speed where the simulation area is kept constant at 1000 x

17

1000 square meter. The first scenario is modelled by using specific the number of nodes

in the fixed area which is 25, 50, 75 and 100 nodes. The second scenario is modelled

by considering different the range of transmission. The transmission range used in this

scenario is 50, 150, 250, 350 and 450 m. As for the third scenario, the speed is set to

0m/s, 4m/s, 8m/s, 12 m/s, 16m/s and 20 m/s in a fixed simulation area. The simulation

result shows DSR performs better than OLSR and ZRP in the performance metrics end

to end delay. In packet delivery ratio, DSR outperforms OLSR and ZRP in all the case.

Lastly, they concluded that DSR is much more better performing protocol followed by

OLSR and ZRP based on the performance metrics used in the simulation.

Moreover, Ashutosh Sharma and Rajiv Kumar conducted a paper “Performance

Comparison and Detailed Study of AODV, DSDV, DSR, TORA and OLSR Routing

Protocols in Ad Hoc Networks” [14] that generates a performance analysis of various

number of ad hoc routing protocols in mobile ad hoc networks. Comparison between

different routing protocols have been done by using different performance metrics like

the average throughput, average packet data ratio and average delay. The results show

that AODV is outperform the other routing protocols in the average throughput. In

addition, OLSR perform best in the scenario of average packet delivery ratio due to the

OLSR perform route selection in acyclic path. Besides, TORA is effective in

performing in dense network by broadcasting the message to all nodes. Lastly, DSR

produces the least delay in the network. They concluded the reactive protocols perform

well in term of average delay and throughput.

18

Lastly, Ako Muhammad Abdullah, Emre Ozen and Husnu Bayramoglu (2019)

conducted “Investigating the Impact of Mobility Models on MANET Routing Protocols”

[15]. In this paper, the authors investigate few mobility models such as Fast Car Model

(FCM), Slow Car Model (SCM), Race Walking Model (RWM) and Human Walking

Model (HWM). These mobility models are designed by the authors with different speed

applied to analyse the performance of AODV, OLSR and GRP protocols with ten pause

time values. Different performance metrics are used to compare the performance

between mobility models with different routing protocol used. For instance, data drop

rate, media access delay, network load, retransmission attempts and throughput. In this

simulation, they show that the performances of these protocols are different from one

model to another. Thus, the results from one model cannot serve as a basis for another

mobility models. From the result of simulation, they deduced that the OLSR protocols

provides better performance than two other routing protocols. In addition, The OLSR

protocol is the most suitable and efficient network routing protocol allowing low delay

and retransmission attempts and higher performance in terms of data transfer from the

source node to the destination node. They also found that the AODV protocol performed

much better compared to OLSR and GRP in respect of data drop rate and network load

in all the configuration of models. AODV network load was a bit high in HWM model

when compared to GRP protocol. In addition, the GRP protocol also yields a much more

lower media access delay and higher throughput than AODV in all scenarios. According

to the results of simulation, they also concluded that they type of application plays a

vital role in determining which protocol should be utilised in the network. For example,

the OLSR protocol is ideal for offering real-time support.

19

2.3 Summary

This chapter manifest and conclude the methods and parameters that were

implemented in the research paper that are related to the evaluation and routing selection

scheme in MANET. This study is crucial to obtain the concept and theory needed to

conduct a successful project.

20

CHAPTER 3

METHODOLOGY

3.1 Introduction

This Chapter discuss the methods and alternatives ways that have been utilised

from the beginning till the end of the following project. The simulation of the project

will also be discussed. The network simulation tools used is NS2 Simulator. In addition,

this chapter will also review the research of methodology and flowchart of the project.

It can provide a better understanding in term of visualization in the implementation of

the project.

3.2 Research of Methodology

In the research of methodology, the planning and scheduling of the project is

crucial for the development of the project. Based on the figure below, there are few

phases of the methodology mentioned. The first phase is related to identifying the

problems regarding the field of research. For this project, the problems of MANET are

identified in this phase. The problem statement is identified based on the related

research paper for a better understanding about MANET and the problems occurred on

MANET. The second phase is designing and developing. The main purpose of the

following phase is to find the suitable method to be implemented in the project. For this

21

project, different mobility speed and network density are used on the OLSR routing

protocol. Next phase in the methodology is the simulation of project. In the following

phase, the simulation that will be used in this project is discussed. The stimulation tool

used for this project will be used for this project is Network Simulator 2 (NS2). In

addition, the last phase is evaluating the performance. The performance metrics of this

project need to be evaluated and analysed. The performance metrics that will be

evaluated are packet delivery ratio, average delay and average throughput.

Figure 3.1: Research Methodology [16].

22

3.3 Simulation

Table 3.1: Comparison of Network Simulator [17]

The simulation of the project is performed with NS2 due to the constraints in

real-life experiment which consume a lot of time and cost. NS2 is used to stimulate the

OLSR routing protocol in current project. NS2 is one of the simulation types utilised in

the network stimulation such as MANET and VANET. This offers emulation for both

wired and wireless networks for routing and multicast protocols. Network Simulator is

authorized under GNU (General Public License) version 2 and is widely referred to as

NS2. Therefore, NS2 is an even-driven, object-oriented and discrete simulator. It is

written in combination of C++ and Octl/tcl programming language. In NS2, C++ is

utilised for thorough protocol implementation and Octl is utilised for the configuration.

The compiled C++ objects are made available to Otcl interpreter in the NS2. This

provides the C++ objects to be managed from the simulator Otcl level. The NS2 is used

for this project because it has the advantages of large number of available models [18].

In addition, UM-OLSR is an OLSR implementation for ns2 network simulator. Thus,

23

UM-OLSR will be used for the simulation of OLSR routing protocol of MANET in this

project.

Figure 3.2: NS2.35 installed in ubuntu 16.04.

Figure 3.3: UM-OLSR is patched into NS2.35.

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3.4 Project Framework

Figure 3.4: Framework of OLSR Routing Protocol.

25

The OLSR protocol consists of two principal mechanisms which is

neighbourhood detection and neighbourhood sensing for topology management. For

both of this mechanism, OLSR protocol uses 4 types of control messages which are

HELLO, TC, MID, and HNA. In addition, neighbourhood sensing is carried out by the

OLSR protocol using the HELLO packets [1]. The distribution of topological

information is performed by the dispersal of TC packet using optimised diffusion or

MPRs. The TC messages contain a list of links in the neighbourhood of the mobile

nodes for the packet management of the OLSR protocol [19]. Besides, the OLSR

protocol takes into account all interfaces kinked to mobile unit by using the MID

messages. Therefore, the noes of the network can utilise all of the available routes

independent of the type of interfaces used at each hop. The OLSR node select one of its

interface address as main address, which it then can be used as a reference in control

messages. Moreover, HNA messages in the OLSR protocol are used to declare

subnetworks and hosts which is outside of the MANET that is reachable by a node

acting as gateway [1].

In neighbourhood sensing, OLSR protocol as a derivative of the classical link-

state protocols maintains a variety of information tables. The tables are updated every

time control messages are received and every time it is sent out. The nodes store a

variety of different tables in the cache:

26

Information tables Explanation

MPR selector set It contains all the local nodes that are selected as MPRs in the

network.

Neighbour Set All the neighbour at one hop distance are saved in the

following table. It is updated dynamically through link set

data. The information involved the symmetric and

asymmetric link neighbours is also stored at this table.

Two-hop neighbour

set

It contains information which is accessible via one hop paths

and this also include the node that inquiry about the

information itself.

In addition, this table may contain similar information of the

same nodes that are appeared in the neighbour set table.

Table 3.2: Table in the cache of the nodes [1].

Furthermore, the HELLO messages have three different roles in OLSR protocol.

The messages are sent to the neighbour at one hop distance for link sensing and

neighbour sensing and to neighbour at two hops away for the two-hop sensing. Lastly,

it functions as an MPR selector sensing which declare the MPRs in the network [1].

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3.5 Project Flowchart of the Route Selection Technique

Figure 3.5: Routing Selection Technique (MPR) [19]

28

OLSR is also known as proactive and table-driven routing protocol. The link

state routing protocols are not subjected to routing loops. In addition, Link state routing

protocol possess no problem in term of scalability. However, link state routing protocol

generates a large amount of traffic during the exchange of topological data in mobile

nodes. Large amount of traffic is an undesirable attribute in MANET due to limited

resources available in MANET [19]. The OLSR protocol implemented a new procedure

or technique to greatly reduce the volume of traffic involved in the process of

exchanging topological data between nodes. In the OLSR protocol, all of the nodes are

authorized and allowed to receive the topological data message. Nevertheless, only a

small number of nodes known as multipoint relays (MPRs) are able to transmit all these

messages across the network. In explanation, The MPRs of the given node are the

minimum number of its immediate neighbours which have the necessities to contact all

its neighbour in two hops. Thus, the MPRs guarantees that the data message of the

network topology will be received by every node in the network.

3.6 Summary

The following chapter clarifies and shows the concept of the research

methodology, framework, and flowchart of the project. It provides a better

understanding for the implementation of the simulator that we selected in this project.

29

REFERENCES

1. Frikha, M. (2011). Ad hoc networks: routing, QoS and optimization. London:

ISTE.

2. Sarkar, S. K., Basavaraju, T. G., & Puttamadappa, C. (2016). Ad Hoc Mobile

Wireless Networks Principles, Protocols, and Applications, Second Edition.

Baton Rouge: CRC Press.

3. Ismail, R., Zulkifli, C. Z., & Samsudin, K. (2016). Routing Protocols for Mobile

Ad-Hoc Network: A Qualitative Comparative Analysis. Jurnal Teknologi, 78(8).

doi: 10.11113/jt.v78.6025

4. Bai, Y., Mai, Y., & Wang, N. (2017). Performance comparison and evaluation

of the proactive and reactive routing protocols for MANETs. 2017 Wireless

Telecommunications Symposium (WTS). doi: 10.1109/wts.2017.7943538

5. Arora, D., Millman, E., & Neville, S. W. (2012). Assessing the Expected

Performance of the OLSR Routing Protocol for Denser Urban Core Ad Hoc

Network Deployments. 2012 IEEE 26th International Conference on Advanced

Information Networking and Applications. doi: 10.1109/aina.2012.93

6. E., Z., & Atef, M. (2017). Performance Evaluation of AODV, DSR and OLSR

in MANET using Opnet Simulator. International Journal of Computer

Applications, 163(11), 23–30. doi: 10.5120/ijca2017913775

7. Naik, L., U., R., & B., R. (2016). Analysis of Node Velocity Effects in MANET

Routing Protocols using Network Simulator (NS3). International Journal of

Computer Applications, 144(4), 1–5. doi: 10.5120/ijca2016910225

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8. Abdullah, A. M., Ozen, E., & Bayramoglu, H. (2019). Investigating the Impact

of Mobility Models on MANET Routing Protocols. International Journal of

Advanced Computer Science and Applications, 10(2). doi:

10.14569/ijacsa.2019.0100204

9. Optimized Link State Routing Protocol (OLSR). (n.d.). Retrieved from

https://tools.ietf.org/html/rfc3626#section-19.

10. Abdulleh, M. N., & Yussof, S. (2015). Performance Analysis of AODV, OLSR

and GPSR MANET Routing Protocols with Respect to Network Size and

Density. Research Journal of Applied Sciences, Engineering and

Technology, 11(4), 400–406. doi: 10.19026/rjaset.11.1794

11. Natarajan, K., & Mahadevan, G. (2017). Mobility based performance analysis

of MANET routing protocols. International Journal of Computer

Applications, 163(10), 37–43. doi: 10.5120/ijca2017913759

12. Performance Comparison of MANET Routing Protocols (OLSR, AODV, DSR,

GRP and TORA) Considering Different Network Area Size. (n.d.). International

Journal of Engineering and Management Research, 6(3), 475–484.

13. Transmission Range, Density & Speed based Performance Analysis of Ad Hoc

Networks. (n.d.). African Journal of Computing & ICT, 8(1), 173–178.

14. Sharma, A., & Kumar, R. (2016). Performance comparison and detailed study

of AODV, DSDV, DSR, TORA and OLSR routing protocols in ad hoc

networks. 2016 Fourth International Conference on Parallel, Distributed and

Grid Computing (PDGC). doi: 10.1109/pdgc.2016.7913218

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15. Abdullah, A. M., Ozen, E., & Bayramoglu, H. (2019). Investigating the Impact

of Mobility Models on MANET Routing Protocols. International Journal of

Advanced Computer Science and Applications, 10(2). doi:

10.14569/ijacsa.2019.0100204

16. Asri, U. S. (2018). An Enhancement of Gateway Selection Scheme in Mobile

Ad-Hoc Network (MANET).

17. Mobile Ad-hoc Network Simulators, a Survey and Comparisons.

(n.d.). International Journal of P2P Network Trends and Technology

(IJPTT), 4(3), 22–26.

18. (n.d.). Retrieved December 21, 2019, from https://www.isi.edu/nsnam/ns/.

19. Moad, D., Djahel, S., & Nait-Abdesselam, F. (2012). Improving the quality of

service routing in OLSR protocol. 2012 International Conference on

Communications and Information Technology (ICCIT). doi:

10.1109/iccitechnol.2012.6285815

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APPENDIX

GANTT CHART FINAL YEAR PROJECT 1

Activity/Week 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Topic

Discussion

Project Title

Proposal

Introduction

Literature

Review

Presentation

Methodology

Draft Report

Submit Draft

Report

Final

Preparation

and

Presentation

Final Report

FYP 1

Gantt Chart 1: Activities and milestones of FYP 1

33