Security for QoS assured wireless and mobile networks

The rapid evolution of wireless technologies as well as their pervasive diffusion in everyday’s life has dramatically changed the world in the last two decades. On one side, service providers/operators can nowadays leverage new wireless technologies to reach new types of customers in a cost effective way; on the other side, end users are actually given richer and more flexible “connectivity opportunities” to obtain the required services. The down side of this scenario deals with the increased complexity in the management of all the system components. Users/customers are becoming more and more demanding in terms of the perceived quality of service (QoS), eventually expecting the very same quality they experience in wired networks in the wireless realm. To this extent, advanced wireless systems must be able to support and manage high-quality services, thus matching the heterogeneous requirements coming from the users. Concurrently, risks and security threats are inherent in any wireless network, and there is an increasing demand for effective security-enforcing techniques to attain authentication, privacy, confidentiality, data integrity, privacy, access control, and non-repudiation, when operating and/or using wireless networks. In this scenario, the deployment of security measures and the provision of QoS represent two critical and tightly coupled challenges in the design of network services, architectures, and protocols in today’s inter-networked world. Such challenges are even made harder in mobile wireless scenarios where the network infrastructure may feature mobile, energy and resource-constrained network devices. To this extent, the success of specific wireless networking technologies is often dependant on the capability of the specific technology to support QoS, on one side, and to provide security, on the other side. The aim of this special issue is to provide an upto-date snapshot on advanced solutions to support the design and deployment of secure and efficient services in wireless mobile networks. The special issue is composed of seven high-quality contributions, each one focusing on a specific component of the aforementioned framework. The first batch of four papers deals with security aspects. The first two papers in the batch focus on security solutions for Wireless Mesh Networks (WMNs); namely, the first one, DSA-Mesh: a Distributed Security Architecture forWMNs, proposes a fully distributed security architecture to ensure security and data confidentiality of the communications occurring in the backbone of a WMN; the proposed solution provides a distributed authentication and access control scheme for the wireless mesh routers taking part in the network, as well as a dynamic key distribution algorithm that supports layer-2 encryption. Whilst the wireless mesh architecture addressed in the first paper is general, in the second manuscript onDifferentiated Security in WMNs, the authors target the design of securemechanisms for IEEE 802.11s-basedWMNs. The rationale andmain contribution of the work is the replication in the wireless environment of the virtual LAN structures typical of the wired networks to achieve protection against internal/external attacks including selective forwarding attacks, routing attacks, and eavesdropping. The third contribution, Fast 802.11 handovers with 802.1X re-authentications, targets the issue of supporting secure client mobility in multi-access point Wireless LAN deployments. Namely, the authors analyze the impact of pre-authentication and re-authentication of a mobile client when handing over between two contiguous WLAN access points, and further propose an advance algorithm to reduce the handover latency while maintaining the authentication of the client itself. The last manuscript dealing with security aspects, Characterizing The Greedy Behavior in Wireless Ad Hoc Networks, switches the focus from static wireless network (wireless mesh and wireless LANs) to dynamic wireless ad hoc networks, by analyzing the network-wide impact of greedy behaviors of single wireless nodes. The authors further introduce a rational greedy strategy in the radio