One of the requirements for enabling two nodes to communicate through a network is the existence of a fully connected path between them. However, there are scenarios in wireless networks where this is not the case and yet nodes still need to communicate freely. Despite concerted efforts to resolve this problem of unconnected wireless nodes trying to relay crucial information, network users still experience significant communication challenges owing to failures or non-existence of critical infrastructural links between nodes and their security challenges. This research work is aimed at enhancing the security component of PRoPHET routing protocol by incorporating internodes cooperation. Simulation was carried out using the opportunistic network environment (ONE). This report presents the modeled opportunistic network using the security aided and group encounter forPRoPHET routing protocol. Node cooperation technique was developed and incorporated into the security aided and groups encounter PRoPHET routing protocol in order to improve its security. For the 20-node test scenario considered, the improved security aided and group encounter PRoPHET routing protocol outperformed the method proposed in the security aided and group encounter PRoPHET routing protocol of Basu et al., (2015) by 19.6%, 7.9%, 34.7% for delivery probability, hop count and buffer timeand for the benchmark Helsinki simulation area considered, it outperformed the method implemented in the work of Basu et al., (2015) by 25.7%, 62.9%, 55.5% with respect to delivery probability, hop count and buffer time respectively. Results showed that, node cooperation technique improved the security aided and groups encounter PRoPHET routing protocol because it increased the delivery probability, reduced the latency, reduced the hop count and increased the buffer time when tested on a 20-node test program and on the bench mark Helsinki simulation area at the end of the simulation time of 44000 seconds.
TABLE OF CONTENTS
TABLE OF CONTENT vi
LIST OF FIGURES x
LIST OF ABBREVIATIONS xi
CHAPTER ONE: INTRODUCTION
1.1 Background 1
1.2 Significance of Research 4
1.3 Problem Statement 4
1.4 Research Aim and Objectives 5
CHAPTER TWO:LITERATURE REVIEW
2.1 Introduction 6
2.2 Review of Fundamental Concepts 6
2.2.1 Opportunistic networks 6
2.2.2 Routing in an Opportunistic Network 7
2.2.3 Other Candidate Routing Protocols for Context-Based Opportunistic Network 9 220.127.116.11 Context-Aware Routing 9
18.104.22.168 Mobility Space Routing (MobySpace Routing) 9
22.214.171.124 Bubble-Rap 9
126.96.36.199 PRoPHET + (Probability Routing using History of Encounter and Transitivity plus) 10
188.8.131.52 PRoPHET (Probability Routing using History of Encounter and Transitivity) 10
2.2.4 PRoPHET Routing Protocol 10
2.2.5 Security Threats and Requirements 12
2.2.6 Disaster Response and Infrastructure 12
2.2.7 Post Disaster Relief Operation 14
2.2.8 PRoPHET for Group Encounter Routing 14
2.2.9 Pin Distributions at the Setup Phase 15
2.2.10 Modifying PRoPHET for Group Encounter Routing 16
2.2.11 Group Encounter Based and Security 17
184.108.40.206 Shelter-Node’s Generation and Encryption of Message 18
220.127.116.11 Signing Message at Shelter-Node to Avoid Bundle Store Overflow Attack 18
18.104.22.168 Handling Identity Spoofing Attack Using Group Based Authentication 19
22.214.171.124 Challenge-Response Technique 19
126.96.36.199 Key Encryption Technique 20
188.8.131.52 Verification of Message at Forwarder-node 21
184.108.40.206 Preventing Black hole attacks Using Encounter Tokens 21
220.127.116.11 Encounter Token Verification at Forwarder-Node 22
2.2.12 Node Cooperation in Opportunistic Network 24
2.2.13 Helsinki simulation area 24
2.3 Review of similar works 25
CHAPTER THREE:MATERIALS AND METHODS
3.1 Introduction 33
3.2 Modelling the Java Platform 34
3.2.1 Java Development Kit 34
3.2.2 Configuring of Environment Variables 34
3.3 Setting up the Java Development Environment 35
3.4 Setting up the ONE Simulator 37
3.4.1 Download the ONE 1.5.1-RC2 37
3.5 Interfacing the IDE with ONE-RC 37
3.6 Setting up the Routing Protocol 37
3.6.1 Modelling PRoPHET Routing Protocol on Test Case 38
3.6.2 Modelling Post Disaster based Scenario for PRoPHET Routing in Helsinki 40
3.6.3 PRoPHET based Node Cooperation 43
CHAPTER FOUR:RESULTS AND DISCUSSIONS
4.1 Introduction 47
4.2 Performance Evaluation for Test Node 47
4.3 Performance Evaluation for Helsinki 50
CHAPTER FIVE:CONCLUSION AND RECOMMENDATIONS
5.1 Introduction 54
5.2 Summary of Findings 54
5.3 Conclusions 54
5.4 Significant Contributions 55
5.4.1 Limitations 55
5.5 Recommendations 56
Appendix A1 61
The program class for PRoPHET routing on the test node 61
Appendix A2 65
Theprogram for PRoPHET routing node cooperation based for the test node 65
Appendix B1 75
Detail Results Obtained for the Test Node without node cooperation 75
Mobile Ad-hoc Network (MANET) is defined as a collection of communication devices or nodes that communicate without any fixed infrastructure and pre-determined organization of available links (Dinakar et al.,, 2012). The Opportunistic Network (OppNet), also called any path routing, is characterized as a necessary evolution of traditional MANET with providing wireless network properties. OppNet consists of both fixed and human-carried mobile devices (nodes) that communicate with each other with or without any infrastructure (a central command station that monitors and controls the activities of the network)(Papaj et al.,, 2012). OppNets are formed by individual nodes. All nodes can be disconnected for some time intervals and each opportunistically exploits any contact with other nodes to forward its messages (Papaj et al., 2012). Each node computes for the best paths based on its knowledge of the routes. The messages are routed and transmitted by “store-carry-forward” model as shown in Fig. 1.1.
Fig.1.1: Example of opportunistic network(Papaj et al., 2012).
The main function of an OppNet is to provide ability to exchange messages between source and destination nodes. Nodes can be of two types, mobile and fixed (Yogi & Chinthala, 2014). They are responsible for the control and management decisions on locally available information in
order to provide effective communication between nodes. The mobility in an OppNet is used to provide efficient communication between unconnected groups of nodes. In MANET, the security mechanisms are based on the assumption that there is a connection between source and target nodes (end-to-end connections). In an OppNet, however, there is need for security solutions, which provide security for all the nodes, all services and applications that participate in routing and transmission process. It is a type of Delay Tolerant Network (DTN) that is composed of mobile and super nodes, and comprising of the following features:(Dumytroet al., 2011).
1. Nodes are intermittently connected.
2. There is no permanent source-destination and end-to-end paths between nodes.
3. Disconnections and reconnections frequently occur between nodes.
4. Network connectivity is highly variable.
All network topologies are variable; moreover, node mobility enables an OppNet to be applied in crisis management areas (Dumytroet al., 2011).
During data transmission, OppNets are connected through user devices as they move, thus completing message transmission. However, this transmission method is accompanied by the security problem of uncertainty during movements. For example, users may not be aware of whether randomly encountered nodes are secured and may be attacked when they encounter malicious nodes (Nicholas et al., 2013). In addition, protecting user‟s personal privacy is another crucial concern. OppNet-related studies have mostly emphasized designing resource-efficient routing methods and have seldom focused on the protection of personal data and privacy. There is sporadic connectivity of nodes and there is need to provide secure delivery of the messages from source node to destination node (Guo et al.,, 2015).
OppNets are going to be the future generation technology with limitless applications and scopes because in times of war, where network becomes sparse or in remote areas of developing countries where there is limited access to the Internet, the OppNet routing protocols promise to be a better message delivery, since it is mainly characterized by store, carry and forward paradigm (Huang et al.,, 2008). With the recent growth in wireless devices, there is a huge opportunity of message delivery where every node can become a participant. Routing in an
OppNet is challenging because it is not known in advance as to when a node will get the opportunity to deliver message to its right next candidate node. Network topology is also unknown to every node in the network and it changes dynamically. Even if an appropriaterouting methodology is chosen, it is hard to know whether a candidate node behaves appropriately or maliciously in the system. Thus, node cooperation is required in a systematic manner. This requires some techniques that let the routing node know the exact behavior of other nodes. This helps in identifying the malicious behavior of nodes in the network. A malicious behavior leads to a considerable delay in the message delivery or no delivery at all to the intended destination in the network under consideration (Wu et al.,, 2015). In such networks, continuous end-to-end connectivity may be impossible. Because of unique features of high mobility of nodes, frequent link variation, and long communication delays, many opportunistic forwarding protocols present major security issues (Wu et al., 2015). The design of OppNets faces serious problems such as how to effectively implement node authentication and access control, confidentiality and data integrity as well as ensuring routing security, privacy protection, cooperation, and trust management. In other words, systematic research on security solutions for forwarding protocols in OppNets is still open and challenging (Basu et al.,, 2015).
For example, any large-scale disasters like flood and cyclone have severe impact on communication infrastructure. Services like cell phone/internet connectivity immediately become non-functional in emergencies due to the failure of the supporting infrastructure through both system damage and system overuse (Luo et al.,, 2006). Therefore, the possibility of information exchange using normal communication infrastructure is almost ruled out. According to the World Disasters Report, (2013), when disaster strikes, access to information is as important as access to food and water (Vinck, 2013). As identified by project RESCUE, any crisis response activity consists of several interrelated phases each of which requires appropriate situational information for its execution (Mehrotra et al.,, 2004). This acute need for information exchange demands setting up of a temporary post-disaster communication network until the normal communication infrastructure is operational again.
Therefore, PRoPHET(Grasic et al.,, 2011) is one of the benchmark routing protocols for DTN. It fits well for such encounter-based forwarding as it uses the history of previous encounters with
other nodes, as well as the transitive properties of the network for bundle forwarding over the network (Grasic et al., 2011). Nevertheless, to use PRoPHET for such group encounter based routing of situational messages; the protocol needs to be aligned with the group mobility patterns and history of group encounters.PRoPHETis one of the major forwarding protocols in an opportunistic network which relies on the implicit assumption that all nodes in the network are honest and are working towards the common goal of message forwarding (Kaur&Kaur, 2009; Orozco et al.,Verma & Srivastava, 2012). However, this assumption turns out incorrect in the presence of unauthorized and malicious nodes that can launch serious attacks like black-hole attack, identity spoofing, bundle store overflow and other forms of attacks on the network. However, some nodes in the opportunistic network may not be willing to participate in the routing process at all times (Ciobanu et al.,, 2015). Thus, a node may be selfish towards another node, for various reasons, for example, it might be low on resources such as battery life, memory or lack of interest in helping nodes outside its own group. The existence of such selfish nodes in an OppNet might leads to messages having high delays or never to be delivered at all, so these nodes must be acknowledged and avoided when possible. Therefore, incorporating security features into PRoPHET for protecting the network from possible attacks and guarding messages from possible eavesdropping are inevitably important in maintaining its operation.
1.2 Significance of Research
The significance of this research work is to ensure availability and to resist malicious dropping in OpptNets where a node may refuse to act as a relay and only settle for sending and receiving its own data or information, thus, causing considerable delay degradation in the network. The improvement which involved the development of a node cooperation routing capable to ensure improvement in network security helped in identifying the malicious behavior of nodes in the network which cause considerable delay in the message delivery or no delivery at all.
1.3 Problem Statement
In OpptNets, there is problem of availability and malicious dropping of messages. There is need to identify those nodes that maliciously drop and cause considerable delay degradation in the message timely delivery. This research work is aimed at improving the existing security aided
and group encounter prophet routing protocol by incorporating node cooperation in to it as a means of controlling malicious behavior of nodes.
1.4 Research Aim and Objectives
This research work is aimed at enhancing the security component of PRoPHET routing protocol by incorporating inter-nodes cooperation. The objectives are:
1. To replicate the SAGE-PRoPHET of Basu et al (2015) and develop the improved SAGE-PRoPHET (ISAGE-PRoPHET) using inter-nodes cooperation.
2. To develop the improve SAGE-PRoPHET of an Opportunistic network using node cooperation technique
3. To simulation environment of the 20-nodes and benchmark Helsinki test in ONE simulator and implement the simulations using the routing protocols in 1.
4. To compare the results obtained in 2 using the metrics of delivery probability, hop count and buffer time management.