Marianne A. Azer

A Survey on Trust and Reputation Schemes in Ad Hoc Networks

The dynamic and cooperative nature of ad hoc networks present substantial challenges in securing these networks. There is a natural incentive for nodes to only consume, but not contribute to the services of the system. Intentional misbehavior can aim at an advantage for the misbehaving node or just constitute vandalism, such as enabling a malicious node to mount an attack or a selfish node to save power. The use of reputation systems in many different areas of IT is increasing because of their widely publicized use in online auctions and product reviews. Reputation systems are used to decide who to trust, and to encourage trustworthy behavior. In this paper we introduce the concept, goals, features and architecture of reputation systems and survey the reputation and trust based security schemes that were proposed for ad hoc networks. Finally we conclude this paper.

Immuning Routing Protocols from the Wormhole Attack in Wireless Ad Hoc Networks

Ad hoc networks can be rapidly deployed and reconfigured. Hence, they are very appealing as they can be tailored to lots of applications. Due to their features they are vulnerable to attacks. A particularly severe security attack, called the wormhole attack, has been introduced in the context of ad-hoc networks. During the attack a malicious node captures packets from one location in the network, and tunnels them to another malicious node at a distant point, which replays them locally. In this paper, we propose a scheme for the wormhole attack prevention in ad hoc networks. The scheme relies on the idea that usually the wormhole nodes participate in the routing in a repeated way as they attract most of the traffic. Therefore, each node will be assigned a cost depending in its participation in routing. The cost function is chosen to be exponential in powers of two such that to rapidly increase the cost of already used nodes. Besides preventing the network from the wormhole attack, the scheme provides a load balance among nodes to avoid exhausting nodes that are always cooperative in routing. In addition, a better network performance has been achieved in terms of traffic

Certification and Revocation Schemes in Ad Hoc Networks Survey and Challenges

Ad hoc networks have many features that make them attractive for the use in many applications. However, there are many unsolved problems in ad hoc networks; securing the network being one of the major concerns. The dynamic and cooperative nature of ad hoc networks present substantial challenges in securing these networks. In this paper, we focus on the role of Certification Authorities (CAs) in securing ad hoc networks communication. We introduce the concept of certification authorities and their selection, we survey and classify the certification schemes and give a brief overview on the revocation schemes. We conclude and end this paper by discussing some challenges and research issues in the certification and revocation in ad hoc networks.

Threshold Cryptography and Authentication in Ad Hoc Networks Survey and Challenges

The dynamic and cooperative nature of ad hoc networks present challenges in securing these networks. There are recent research efforts in securing ad hoc networks. Amongst security approaches, there are threshold cryptography and authentication. In this paper we survey the threshold cryptography based schemes and the authentication schemes that have been proposed to secure ad hoc networks. We conclude this paper and identify the challenges and open research areas associated with each of these approaches.

A secure and privacy-preserving event reporting scheme for vehicular Ad Hoc networks

In vehicular ad hoc networks, vehicles should report events to warn the drivers of unexpected hazards on the roads. While these reports can contribute to safer driving, vehicular ad hoc networks suffer from various security threats; a major one is Sybil attacks. In these attacks, an individual attacker can pretend as several vehicles that report a false event. In this paper, we propose a secure event-reporting scheme that is resilient to Sybil attacks and preserves the privacy of drivers. Instead of using asymmetric key cryptography, we use symmetric key cryptography to decrease the computation overhead. We propose an efficient pseudonym generation technique. The vehicles receive a small number of long-term secrets to compute pseudonyms/keys to be used in reporting the events without leaking private information about the drivers. In addition, we propose a scheme to identify the vehicles that use their pool of pseudonyms to launch Sybil attacks without leaking private information to road side units. We also study a strong adversary model assuming that attackers can share their pool of pseudonyms to launch colluding Sybil attacks. Our security analysis and simulation results demonstrate that our scheme can detect Sybil attackers effectively with low communication and computation overhead. Copyright

Security in Ad Hoc Networks: From Vulnerability to Risk Management

Mobile Ad hoc Networks (MANETs) have lots of applications. Due to the features of open medium, absence of infrastructure, dynamic changing network topology, cooperative algorithms, lack of centralized monitoring and management point, resource constraints and lack of a clear line of defense, these networks are vulnerable to attacks. A vital problem that must be solved in order to realize these applications is that concerning the security aspects of such networks. Solving these problems combined with the widespread availability of devices such as PDAs, laptops, small fixtures on buildings and cellular phones will ensure that ad hoc networks will become an indispensable part of our life. In this paper, we discuss the reasons of vulnerability as well as active and passive attacks on such networks. We present the security measures used to secure ad hoc networks such as authentication, threshold cryptography, trust and reputation, and present a risk management scheme. Concluding remarks are presented at the end of this paper, while mentioning the different open research areas and challenges in the discussed security measures.

A Novel Proximity Based Trust Model for Opportunistic Networks

Trust should be earned. This is a famous quote that we use everyday implicitly or explicitly. Trust often is an inherent characteristic of our daily life, but in the digital community and between devices how can we represent trust? Since our mobile and digital devices became our confidants, we cannot share the information embedded in these devices with other devices without establishing trust. Hence, in this research a proximity based trust model based on Homophily principle is proposed. Earlier social studies have shown that people tend to have similarities with others in close proximity. In such clustered communities of interest people tend to communicate, socialize and potentially trust each other. In this paper, a novel proximity based trust model is built taking into consideration different aspects like cooperation or unselfishness, honesty, similarity and Activity.

Combating Sybil Attacks in Vehicular Ad Hoc Networks

Vehicular Ad Hoc Networks (VANETs) are considered as a promising approach for facilitating road safety, traffic management, and infotainment dissemination for drivers and passengers. However, they are subject to an attack that has a severe impact on their security. This attack is called the Sybil attack, and it is considered as one of the most serious attacks to VANETs, and a threat to lives of drivers and passengers. In this paper, we propose a detection scheme for the Sybil attack. The idea is based on public key cryptography and aims to ensure privacy preservation, confidentiality, and non-repudiation. In addition, we suggest a scalable security and privacy solution using short-lived and authenticated certificates that must be issued from the national certification authority in order to guarantee trust among vehicles.

Cluster Head election in Wireless Sensor Networks

Wireless Sensor Networks (WSNs) consist of a collection of cheap, easy to deploy Sensor nodes arranged together to fulfill a specific purpose (monitoring, tracking ...etc.). A WSN network is composed of a Base Station (BS) and collection of sensors. There are a lot of approaches for the network construction. Amongst them is the hierarchical structure, where the network is divided into clusters and the node inside this cluster communicates with BS through a chosen leader called Cluster Head (CH). In this paper, we present cluster-Head election algorithms for WSNs. We will discuss the operations of these algorithms, and compare their performance.

Lightweight Authentication Protocol Deployment over FlexRay

In-vehicle network security is becoming a major concern for the automotive industry. Although there is significant research done in this area, there is still a significant gap between research and what is actually applied in practice. Controller area network (CAN) gains the most concern of community but little attention is given to FlexRay. Many signs indicate the approaching end of CAN usage and starting with other promising technologies. FlexRay is considered one of the main players in the near future. We believe that migration era is near enough to change our mindset in order to supply industry with complete and mature security proposals with FlexRay. This changing mindset is important to fix the lagging issue appeared in CAN between research and industry. Then, we provide a complete migration of CAN authentication protocol towards FlexRay shows the availability of the protocol over different technologies.