Security Of Wireless Networks

Along with the development and application of wireless networks, more and more concerns are put on security issues. Compared with their wired counterparts, wireless networks risk much more due to their open and instable wireless channels, severe constrains on wireless terminals, and frequently changed topology. In consequence, wireless network is susceptible to many security attacks, which can be defended effectively by using cryptographic protocol. Among all security objectives, authentication and key agreement are essential on which most other goals are relied. The thesis focuses on security technique and methods in wireless networks, including wireless communication networks, Ad Hoc networks, and wireless sensor networks. The key contributions follow below.1. After analyzing security protocols, especially formal methods for authentication protocols, a new authentication protocol is proposed and a formal analysis is given. It is shown from the result that most security goals are met.2. General rules for designing authentication protocols in wireless networks are summarized through analyzing existing protocols, and then a new lightweight authentication protocol is designed for wireless environment based on public key signatures and hash functions.3. End-to-end communication plays an increasing important role in various applications, so we investigate existing such schemes, based on which a new paradigm is proposed. The flaws get fixed in new protocol, and it also shares some advantages over previous schemes.4. It is difficult to authenticate nodes in Ad Hoc networks because there have no infrastructure to rely on. We propose a security protocol with improved performance based on threshold cryptology.5. Wormhole attack is dangerous for Ad Hoc networks and difficult to detect. After proposing an attack model for wormhole attack, we find it is possible to detect and defense such attacks using traffic monitoring.6. Key distribution is far from a trivial work in WSNs for various reasons. Based on their key features, a new framework is proposed in which different keying schemes can be fulfilled.