Layered Security in Plant Control Environments

Ken Miller Senior Consultant
Ensuren Corporation

KEYWORDS

Plant Controls, Layered Security, Access Control, Computing Environment, Examination, Detection, Prevention, Encryption, Compartmentalization

ABSTRACT

Process control vendors are migrating their plant control technologies to more open network and operating environments such as Unix, Linux, Windows, Ethernet, and the Internet Protocol. Migrating plant controls to open network and operating environments exposes all layers of the computing environment to unauthorized access. Layered security can be used to enhance the level of security for any computing environment. Layered security incorporates multiple security technologies in each computing layer to provide resistance to unauthorized intrusion, while reducing the risk of failure from a single technology. Layered security requires acceptance of a model, development of an access control plan, compartmentalization of the network, and implementation of core security products that address examination, detection, prevention, and encryption. Layered security is considered a “best practice” in any computing environment, and should be widely used in critical control environments.

INTRODUCTION

Plant control environments have traditionally been built on proprietary technology. This proprietary technology provided a reasonable level of security from unauthorized access due to its “closed” nature, and lack of connection to business networks and the Internet. However, vendors are beginning to migrate their plant control technology to more open network and operating environments such as Unix, Linux, Windows, Ethernet, and the Internet Protocol. In some instances, plant control environments have access to the Internet. This migration is driven by the need to offer advanced graphical user interfaces to manage