Panagiotis Karkazis

A Novel Trust-Aware Geographical Routing Scheme for Wireless Sensor Networks

AbstractWireless sensor networks are vulnerable to a wide set of security attacks, including those targeting the routing protocol functionality. The applicability of legacy security solutions is disputable (if not infeasible), due to severe restrictions in node and network resources. Although confidentiality, integrity and authentication measures assist in preventing specific types of attacks, they come at high cost and, in most cases, cannot shield against routing attacks. To face this problem, we propose a secure routing protocol which adopts the geographical routing principle to cope with the network dimensions, and relies on a distributed trust model for the detection and avoidance of malicious neighbours. A novel function which adaptively weights location, trust and energy information drives the routing decisions, allowing for shifting emphasis from security to path optimality. The proposed trust model relies on both direct and indirect observations to derive the trustworthiness of each neighboring node, while it is capable of defending against an increased set of routing attacks including attacks targeting the indirect trust management scheme. Extensive simulation results reveal the advantages of the proposed model.

Design of primary and composite routing metrics for RPL-compliant Wireless Sensor Networks

The diversity of applications that current and emerging Wireless Sensor Networks (WSNs) are called to support imposes different requirements on the underlying network with respect to delay and loss, while at the same time the WSN imposes its own intricacies. The satisfaction of these requirements highly depends on the metric upon which the forwarding routes are decided. In this view, the IETF ROLL group has proposed the RPL routing protocol, which can flexibly work on various routing metrics, as long as they hold specific properties. The system implementer/user is free to decide whether to use one or multiple routing metrics, as well as the way these metrics can be combined. In this paper, we provide ways to quantify the routing metrics so that they can be combined in an additive or lexical manner. We use extensive simulation results to evaluate the impact of several routing metrics on the achieved performance.

Combining trust with location information for routing in wireless sensor networks

As the applications of wireless sensor networks proliferate, the efficiency in supporting large sensor networks and offering security guarantees becomes an important requirement in the design of the relevant networking protocols. Geographical routing has been proven to efficiently cope with large network dimensions while trust management schemes have been shown to assist in defending against routing attacks. Once trust information is available for all network nodes, the routing decisions can take it into account, i.e. routing can be based on both location and trust attributes. In this paper, we investigate different ways to incorporate trust in location-based routing schemes and we propose a novel way of balancing trust and location information. Computer simulations show that the proposed routing rule exhibits excellent performance in terms of delivery ratio, latency time and path optimality. Copyright

Evaluating routing metric composition approaches for QoS differentiation in low power and lossy networks

The use of Wireless Sensor Networks (WSN) in a wide variety of application domains has been intensively pursued lately while Future Internet designers consider WSN as a network architecture paradigm that provides abundant real-life real-time information which can be exploited to enhance the user experience. The wealth of applications running on WSNs imposes different Quality of Service requirements on the underlying network with respect to delay, reliability and loss. At the same time, WSNs present intricacies such as limited energy, node and network resources. To meet the application’s requirements while respecting the characteristics and limitations of the WSN, appropriate routing metrics have to be adopted by the routing protocol. These metrics can be primary (e.g. expected transmission count) to capture a specific effect (e.g. link reliability) and achieve a specific goal (e.g. low number of retransmissions to economize resources) or composite (e.g. combining latency with remaining energy) to satisfy different applications needs and WSNs requirements (e.g. low latency and energy consumption at the same time). In this paper, (a) we specify primary routing metrics and ways to combine them into composite routing metrics, (b) we prove (based on the routing algebra formalism) that these metrics can be utilized in such a way that the routing protocol converges to optimal paths in a loop-free manner and (c) we apply the proposed approach to the RPL protocol specified by the ROLL group of IETF for such low power and lossy link networks to quantify the achieved performance through extensive computer simulations.

A novel flexible trust management system for heterogeneous wireless sensor networks

Security has been recognised as a key issue for the expansion of wireless sensor network applications. To defend against the wide set of security attacks, legacy security solutions are not applicable due to the very limited memory and processing resources of the sensor nodes as well as due to the reason that sensor networks are required to operate in an autonomous infrastructureless manner. Trust management schemes consist a powerful tool for the detection of unexpected node behaviours (either faulty or malicious). Once misbehaving nodes are detected, their neighbours can use these information to avoid cooperating with them either for data forwarding, data aggregation or any other cooperative function. We propose a novel trust management system based on both direct and indirect trust information, which allows for fast detection of a wide set of attacks, including those addressing the reputation exchange scheme, while energy awareness is also incorporated in our approach.

RPL modeling in J-Sim platform

Recently, Routing Protocol for Low Power and Lossy Networks (RPL) has been proposed by IETF ROLL WG in order to cope with Low Power and Lossy Networks (LLN) requirements implied by different application domains. In this paper, we present RPL modeling in J-Sim simulation environment, providing a complete simulation framework for performance evaluation as well as experimentation on open issues, such as the support of multiple instances and the definition of routing strategies based on the composition of several metrics.

Secure geographic routing in ad hoc and wireless sensor networks

Security in sensor networks is one of the most relevant research topics in resource constrained wireless devices and networks. Several attacks can be suffered in ad hoc and wireless sensor networks (WSN), which are highly susceptible to attacks, due to the limited resources of the nodes. In this paper, we propose innovative and lightweight localization techniques that allow for intrusion identification and isolation schemes and provide accurate location information. This information is used by our routing protocol which additionally incorporates a distributed trust model to prevent several routing attacks to the network. We finally evaluate our algorithms for accurate localization and for secure routing which have been implemented and tested in real ad hoc and wireless sensor networks.

Trust-aware and link-reliable routing metric composition for wireless sensor networks

The usability of wireless sensor networks in modern applications requires the fulfillment of dynamic Quality of Service QoS requirements that can only be met in a reactive manner by the introduction of composite routing metrics, capturing several distinct network characteristics. However, combining routing metrics is neither a trivial nor an arbitrary task, given the routing protocol requirements and routing metrics properties. In this paper, the theoretical framework of routing algebra formalism is adopted and extended to incorporate single or composite routing metrics, because the satisfaction of routing algebra properties ensures convergence, optimality, and loop-freeness. Moreover, packet forwarding indication is defined as a new trust metric for systems a with or b without network retransmissions to avoid forwarding attacks, while a novel composite routing metric is presented, combining link reliability and trust-awareness in an additive manner, fulfilling the theoretical requirements. Finally, this composite metric is applied to the Routing Protocol for Low Power and Lossy Networks via simulations, which verify its efficiency in several scenarios, including the comparison between lexical and additive metric composition approaches. Copyright

Managing QoS for Future Internet Applications over Virtual Sensor Networks

The integration of Wireless Sensor Networks (WSNs) in the Future Internet has opened new opportunities for novel applications that meet the needs of modern societies. Virtualisation of the available resources and the services offered by WSNs enables their efficient sharing between diverse applications reducing costs. Responding to this challenge, the VITRO project has designed a WSN virtualization architecture that targets to decouple the physical sensor infrastructure from the applications running on top of it. In the concept of Virtual Sensor Network platform, the WSNs are capable of collaborating among each other (even if they belong to different administrator domains or comprise of heterogeneous platforms) to flexibly support service composition and fuel novel application development. To meet the diverse Quality of Service (QoS) requirements imposed by the different applications running on top of the same infrastructure, VITRO has designed, implemented and integrated a routing solution that enables the establishment of different routing paths per application, based on different routing criteria in order to optimize the performance aspect(s) of interest to each application. In this paper, we demonstrate how the VITRO routing solution could be employed in various use cases including smart homes/buildings, smart cities, smart business environments and security-related applications. We evaluate the achieved performance using computer simulation results and provide guidelines for prospective users.

Efficient Detection of Routing Attacks in Wireless Sensor Networks

A lot of effort has been spent in securing the routing procedure in wireless sensor network (WSNs) since this is accomplished in a cooperative way and is vital for the communication of the sensors with the base station which collects the sensed data. The communication over wireless links in combination with the ad hoc organization introduces vulnerabilities. Each node monitors the behaviour of its neighbours in order to check whether they behave maliciously or not. Nodes with low trustworthiness are then avoided during routing decisions which are based on location and trust information. The efficiency of the proposed approach in defending against black-hole, grey-hole and integrity attacks is evaluated using computer simulations.