The combination of computer system security into existing Computer Science undergraduate education is a critical and convoluted errand. With the expanding danger of computer intrusion, PC violations, and data wars, Computer Science instructors bear the duty of developing another age of graduates who know of computer security related issues and are outfitted with appropriate information and skills to tackle the issues. The errand of incorporating PC security into existing Computer Science programs, in any case, is confounded because of the way that most faculty individuals do not have the forte information in this field. Computer system security contracts with the administrative process and technical protection applied to computer software, hardware, and information to guarantee against unintentional illegal permission to computer system information. This paper introduces the system security technologies including validation, data encryption technology, firewall technique, antivirus technology, intrusion detection system, and VPN (a virtual private network).