The course Network Security covers the principles and practice of computer and telecommunication network security with particular emphasis on Internet security. After transferring the fundamentals of IT security and cryptography to the networking domain, we follow a top-down approach to network security. Starting with the application layer, the course provides a detailed discussion of network security principles and protocols. In addition to well known mechanisms, recent developments in the area of network security (e.g., peer-to-peer security, mobile network security, etc.) will be thoroughly examined. Further static course information can be found on the SEEMOO homepage.