Enhancement of security in the hierarchy model of control and automation by applying Single Sign-On approach for web services

Information security is an important term in both fields of IT systems and control systems. Thus, security requirements should be always considered in design phase. Modern approaches in manufacturing and automation technology such as: DPWS and OPC UA tend to integrate control system networks to the computer networks by the aid of service-oriented architecture technology. Single Sign-On is a property of access control in information security which focuses on authentication mechanism. It can be performed across federated domains and provides a single entry point for the user that can login only once and become capable of accessing to disparate protected resources in different locations. The Security Assertion Markup Language (SAML) can be used invisibly in background of system and apply as the standard for providing Single Sign-On mechanism by exchanging identity information to different security domains regardless of the specific authentication protocol which is used for identities in that domain. This paper proposes the model for performing of Single Sign-On approach for protected devices and applications that support web services technology and locate across different boundaries of the hierarchy model of control and automation.