As the advances in networking technology help to connect any part of the globe, and openness and scalability of the Internet is opening up a number of new on-line applications, the threats from attackers has also grown drastically. In recent years, attackers have shown increasing sophistication in their ability to launch attacks which threaten the security of the devices connected to the Internet.

Accordingly, this volume discusses the design of effective Intrusion Detection Systems (IDS), clustering techniques in designing anomaly based IDS, network traffic analysis for security analysis, special properties of Elliptic curves in the context of designing security tools, use of a spatio-temporal logic for checking anomalies in filtering rules as model checking in PSPACE, automated intrusion signatures generation technique, use of sensor fusion in IDS, mechanisms for SPIT prevention, detection mechanism for SQL injection attacks, prevention of unknown malware attack, vulnerabilities in web browsers, security issues in ICMP, reputation systems for online community, copyright protection of digital image, multimedia encryption techniques, attacks and countermeasures in WSNs, WMNs, and P2P networks, key agreement and authentication protocols in UMTS.