Secure Web-based monitoring and control system

Recently, we have been seeing more and more examples of Web-based monitoring and control systems (WMCSs) with the widespread use of Internet technologies. On the Internet, however, systems or network services are subject to damage from various threats. In this paper, we discuss a secure WMCS whose purpose and objective is to allow operations by authorized users via an intranet, while excluding unauthorized operations. A very important component to protect a control network or devices in a WMCS is a firewall that is called a "plant firewall" (PFW). We propose the main functions of a PFW for securing a WMCS. Those functions are: user authentication, operation rights management, command filtering, progress reporting, communication path encryption, access logging and format conversion.