Service-Oriented Bandwidth Borrowing Scheme for Mobile Multimedia Wireless Networks

Multimedia applications (audio phone, video on demand, video conference, file transfer, etc.) will be integrated into future mobile communication systems. Bandwidth is the most critical resource in mobile multimedia wireless networks. Due to mobile user mobility and limited bandwidth in the mobile wireless communications networks, the quality-of-service (QoS) guarantee becomes very complicated for multimedia applications. Therefore, the available bandwidth of wireless networks should be managed in the most efficient manner. In order to provide mobile hosts (MHs) with highly satisfying degree of QoS in mobile communication systems, new and efficient bandwidth allocation schemes must be developed. In this paper, we propose and evaluate a novel scheme for bandwidth borrowing in mobile multimedia wireless networks. We employ a service-oriented bandwidth borrowing strategy to reduce the overhead of bandwidth reconfiguration and to satisfy QoS requirements of ongoing MHs in cellular systems. Furthermore, we design efficient call admission control algorithms for different multimedia services. The QoS guarantees can be maintained at a comfortable level in cellular systems. Simulation results show that our proposed scheme outperform the previously proposed scheme

Security and Privacy Issues in Wireless Mesh Networks: A Survey

This book chapter identifies various security threats in wireless mesh network (WMN). Keeping in mind the critical requirement of security and user privacy in WMNs, this chapter provides a comprehensive overview of various possible attacks on different layers of the communication protocol stack for WMNs and their corresponding defense mechanisms. First, it identifies the security vulnerabilities in the physical, link, network, transport, application layers. Furthermore, various possible attacks on the key management protocols, user authentication and access control protocols, and user privacy preservation protocols are presented. After enumerating various possible attacks, the chapter provides a detailed discussion on various existing security mechanisms and protocols to defend against and wherever possible prevent the possible attacks. Comparative analyses are also presented on the security schemes with regards to the cryptographic schemes used, key management strategies deployed, use of any trusted third party, computation and communication overhead involved etc. The chapter then presents a brief discussion on various trust management approaches for WMNs since trust and reputation-based schemes are increasingly becoming popular for enforcing security in wireless networks. A number of open problems in security and privacy issues for WMNs are subsequently discussed before the chapter is finally concluded.Comment: 62 pages, 12 figures, 6 tables. This chapter is an extension of the author's previous submission in arXiv submission: arXiv:1102.1226. There are some text overlaps with the previous submissio