The modern context of quick technological evolution has nowadays let computer science to reach people in both professional and private spheres. In a world where technologies are accessible to everyone, the gates to cyber-crimes are opened to any computer fan with some knowledge and skills. In this dangerous environment, individuals, companies, organisations, and institutions must protect themselves against criminals. The presence of a stable and reliable security system is now crucial in every technology ambience since crimes are increasing in number, types, and ease of execution. The security of a system can be reached building a shield which must cover all the different aspects of protection.