Book excerpt: This valuable handbook is a comprehensive compilation of state-of-art advances on security in computer networks. More than 40 internationally recognized authorities in the field of security and networks contribute articles in their areas of expertise. These international researchers and practitioners are from highly-respected universities, renowned research institutions and IT companies from all over the world. Each self-contained chapter covers one essential research topic on security in computer networks. Through the efforts of all the authors, all chapters are written in a uniformed style; each containing a comprehensive overview, the latest pioneering work and future research direction of a research topic.