A collaborative trust management scheme for emergency communication using delay tolerant networks

Delay Tolerant Network (DTN) comprises of nodes with small and limited resources including power and memory capacity. We propose the use of DTN as an alternate means of communication for the dissemination of emergency information in a post-disaster evacuation operation. We investigate the performance of DTN in providing emergency communication support services under packet dropping attacks. We consider internally motivated attacks where the nodes that are part of the emergency rescue team are compromised with malicious behaviours thereby dropping packets to disrupt the message dissemination during the evacuation operation. A way to mitigating malicious behaviour and improve network performance of DTN is to use incentives in exchanging information between nodes. Unlike existing schemes, we consider the Basic Watchdog Detection System which detects and acts against misbehaving nodes to reduce their overall impact on the network performance. We design a Collaborative Trust Management Scheme (CTMS) which is based on the Bayesian detection watchdog approach to detect selfish and malicious behaviour in DTN nodes. We have evaluated our proposed CTMS through extensive simulations and compared our results with the other existing schemes. Our evaluations show that the use of adequate collaborative strategies between well behaved nodes could improve the performance of Watchdog schemes taking into account the delivery ratio, routing cost and the message delay from the source node to the destination node

A collaborative trust management scheme for emergency communication using delay tolerant networks

Delay Tolerant Network (DTN) comprises of nodes with small and limited resources including power and memory capacity. We propose the use of DTN as an alternate means of communication for the dissemination of emergency information in a post-disaster evacuation operation. We investigate the performance of DTN in providing emergency communication support services under packet dropping attacks. We consider internally motivated attacks where the nodes that are part of the emergency rescue team are compromised with malicious behaviours thereby dropping packets to disrupt the message dissemination during the evacuation operation. A way to mitigating malicious behaviour and improve network performance of DTN is to use incentives in exchanging information between nodes. Unlike existing schemes, we consider the Basic Watchdog Detection System which detects and acts against misbehaving nodes to reduce their overall impact on the network performance. We design a Collaborative Trust Management Scheme (CTMS) which is based on the Bayesian detection watchdog approach to detect selfish and malicious behaviour in DTN nodes. We have evaluated our proposed CTMS through extensive simulations and compared our results with the other existing schemes. Our evaluations show that the use of adequate collaborative strategies between well behaved nodes could improve the performance of Watchdog schemes taking into account the delivery ratio, routing cost and the message delay from the source node to the destination node

Experimental Privacy Analysis and Characterization for Disconnected VANETs

Intelligent Transport Systems (ITS) are special applications of Vehicular Ad-hoc Networks (VANETs) for road safety and efficient traffic management. A major challenge for ITS and VANETs in all its flavours is ensuring the privacy of vehicle drivers and the transmitted location information. One attribute of ITS during its early roll-out stage especially in rural areas and challenged environments is low vehicle density and lack of end-to-end connectivity akin to the attribute of Vehicular Delay Tolerant Networks (VDTNs). This means that contact duration between network entities such as vehicles and road-side units (RSUs) are short-lived. Three popular solutions are the use of pseudonyms, mix-zones, and group communication. Privacy schemes based on the mix-zone technique abound for more conventional VANETs. A critical privacy analysis of such scenarios will be key to the design of privacy techniques for intermittent networks. We are not aware of any work that analyse the privacy problem in intermittent VANTEs. In this paper, we add our voice to efforts to characterize the privacy problem in disconnected VANETs

A Distributed Trust Management Scheme for Data Forwarding in Satellite DTN Emergency Communications

Satellite Communications can be used when other communication systems are either destroyed or overloaded. Observation satellites and Delay/Disruption Tolerant Networks are technologies that can be interconnected to provide emergency communication for disaster recovery operations. DTNs use a store-carry-forward mechanism to forward messages through intermediary nodes to the destination node. The reliability of relaying messages through multi-hop nodes poses a significant problem in DTNs due to lack of consistent connectivity. These network characteristics make DTNs to heavily rely on the cooperation of neighbouring nodes for the successful delivery of packets. However, the presence of malicious or selfish nodes will have a great impact on the network performance. In this paper, we design a decentralised trust management scheme (DTMS) to filter out malicious nodes in DTNs. First, the number of forwarding evidence are combined with the energy consumption rate of the nodes to formulate direct trust. Then, a recommendation trust is computed from the indirect trust, recommendation credibility and recommendation familiarity. Recommendation credibility and familiarity improve the overall recommendation trust by filtering out dishonest recommendations. A comparative analysis of DTMS is performed against a Cooperative Watchdog Scheme (CWS), Recommendation Based Trust Model (RBTM) and Spray & Wait protocol. The results show that DTMS can effectively deal with malicious behaviours in DTNs including trust related attacks

Blockchain-Based Dynamic Key Management for Heterogeneous Intelligent Transportation Systems

As modern vehicle and communication technologies advanced apace, people begin to believe that Intelligent Transportation System (ITS) would be achievable in one decade. ITS introduces information technology to the transportation infrastructures and aims to improve road safety and traffic efficiency. However, security is still a main concern in Vehicular Communication Systems (VCS). This can be addressed through secured group broadcast. Therefore, secure key management schemes are considered as a critical technique for network security. In this paper, we propose a framework for providing secure key management within the heterogeneous network. The security managers (SMs) play a key role in the framework by capturing the vehicle departure information, encapsulating block to transport keys and then executing rekeying to vehicles within the same security domain. The first part of this framework is a novel network topology based on a decentralised blockchain structure. The blockchain concept is proposed to simplify the distributed key management in heterogeneous VCS domains. The second part of the framework uses the dynamic transaction collection period to further reduce the key transfer time during vehicles handover. Extensive simulations and analysis show the effectiveness and efficiency of the proposed framework, in which the blockchain structure performs better in term of key transfer time than the structure with a central manager, while the dynamic scheme allows SMs to flexibly fit various traffic levels

Security and Privacy in Location-Based Services for Vehicular and Mobile Communications: An Overview, Challenges and Countermeasures

Location-based Services (LBS) have gained popularity as a result of the advances in mobile and communication technologies. LBS provide users with relevant information based on their location. In spite of the desirable features provided by LBS, the geographic location of users are not adequately protected. Location privacy is one of the major challenges in vehicular and mobile networks. In this article, we analyse the security and privacy requirements for LBS in vehicular and mobile networks. Specifically, this paper covers privacy enhancing technologies and cryptographic approaches that provide location privacy in vehicular and mobile networks. The different approaches proposed in literature are compared and open research areas are identified