Information security is an increasingly important concern among many corporate leaders and system managers who are responsible for computer systems. A modern Information Technology (IT) system, drastically changing the current business/management, is structured by an open system where many different disturbances (e.g., corporate secret agents, hackers and terrorists) influence the IT-based decision making process and business performance/practice. This study is concerned about such a security issue, in particular focusing upon how the infrastructure of a corporate network is protected from hostile agents. The study is also interested in whether the security issue influences our corporate decision making in the e-business world.