Cyberspace security consists of three parts – information security, system security, and application security. Information security leverages cryptographical mechanisms to guarantee data privacy; system security leverages sandboxing, program analysis etc. to guarantee the authentication and privacy of system usage; application security leverage anomaly behavior detection to recognize malicious user and software. In this course, we would discuss typical security issues and solutions in each section, and require students to practice them in course projects. We would also research into new security issues in latest scenarios and new technologies (e.g., machine learning, trusted execution environment) that can be used to solve security problems.