Introduction to computer security and information and communication technology, encryption techniques, introduction to number theory, public key algorithm, key management, hash function, digital signature and authentication protocol, electronic mail security, Internet Protocol (IP) security (IPsec), Lan security, web security, virus, worm, firewall, intrustion detection and prevention, hacker, software and hardware security, information technology security management, risk analysis and management, digital forensics, ethic, computer security law.