There are many kinds of control networks which have been used in various non-IP network areas, such as BA (Building Automation), FA (Factory Automation) and PA (Process Automation). These do not incorporate reasonable security mechanisms as they have been mainly used for closed networks. Recently the security of control networks is becoming important because of the popularization of the Internet, the deployment of wireless technologies and the security requirements of such infrastructures. Control networks require security mechanisms which 1) enable end-to-end security that do not depend upon specific network topology, 2) work with multiple control network technologies, and 3) are suited to small embedded devices commonly used in control networks. This paper shows security mechanisms which can meet the above requirements, assuming that IP is applied to the control networks.