Certificate Based Security at Device Level of Automation System

This paper discusses the security at device level of automation system. Process networks are traditionally considered to be isolated networks. However manufacturers of devices tend to use backdoor in their products to remotely manage them. Also merging of TCP/IP-stack and using wireless connections at device level is gaining interest. Therefore the assumption of isolation is rejected and some security measures at device level are considered in this paper. OPC UA is an application framework that enables global connectivity. There is some security consideration in the specification of OPC UA. However these security measures aren't efficient enough to be used at device level. Thus, implementing a new authentication only security policy profile or using OPC UA for data transfer and IPSec for authentication is proposed.