GB/T 33009.1-2016Industrial automation and control system security—Distributed control system(DCS)—Part 1: Protection requirements (English PDF)

3.1 Terms and definitions

3.1.6 Control system security

The goal is to protect the control system availability, integrity, and, confidentiality, also including real-time, reliability and stability.

3.1.7 Human machine interface

A set of methods that employees (users) can interact with specific machines, equipment, computer programs, or other complex tools (systems).

Note: In many cases, these include video or computer terminals, buttons, audible feedback, flashing lights, and so on. The human machine interface provides methods that include. input (allowing the user to control the machine), output (allowing the machine to notify the user).

3.1.8 Identification

The process of identifying and discerning an assessment element. [GB/T 30976.1-2014, Definition 3.1.2]

3.1.9 Security risk

The occurrence of security incident and its influence onto organizations due to the threat use of vulnerability in man-made or natural systems and their management systems. [GB/T 20984-2007, Definition 3.6]

3.1.10 Integrity

Characteristics that ensure that information and information systems are not altered or broken by unauthorized persons, including data integrity and system integrity. [GB/T 20984-2007, Definition 3.10]

3.1.21 Threat

Potential causes of unwanted accidents that can cause harm to the system or organization. [GB/T 20984-2007, Definition 3.17]

3.1.22 Vulnerability

Defects or weaknesses in system design, implementation, or operation and management, which can be exploited to compromise system integrity or security policies. [GB/T 30976.1-2014, Definition 3.1.1]

3.2 Abbreviations

The following abbreviations apply to this document.

DCS. Distributed Control System MES. Manufacturing Execution System DoS. Denial of Service

4.1 DCS system overview

4.1.1 Network structure of common DCS system application

DCS system applications are usually a vertical hierarchical network structure, from top to bottom including process monitoring layer, field control layer and field equipment layer. Each layer is connected by a communication network, and each equipment in each layer is communicated through a communication network of the same level. The typical network structure is as shown in Figure 1. This part mainly proposes requirements for security requirements of the process monitoring layer, field control layer network, and field equipment layer network in the DCS system. The description of each layer is as follows. […]

4.2 DCS protection overall requirements and principles

4.2.1.2 External network isolation requirements

DCS user enterprise topological structure may be deployed in hierarchical manner. If the DCS system network is directly or indirectly interconnected with the external network (other networks than such DCS system network as the enterprise management network, the internet), physical or logic isolation technical measures shall be used between the DCS system network and external network for protection.

4.2.1.3 Network link requirements

For DCS system applications deployed in multiple zones and interconnected by networks, the resources of the internet link shall be sufficient. That is, when the business traffic reaches the maximum peak, the link data communication is normal, and the network delay still meets the requirements of the DCS system.

For enterprise users with high requirements on network interoperability and stability, link redundancy technologies and means can be adopted to ensure that the enterprise network can maintain basic communication in the event of a network failure, so that when one link fails, the other link can provide network protection of the normal production and operation of enterprises.

Enterprise users having higher network interoperability and stability can deploy enterprise core business networks, backbone networks, core control networks in a physical line redundancy method, and the redundant line network can be constructed by other network construction methods different from the main network.

4.2.1.4 Data backup requirements

General DCS system shall have real-time data, OPC data, configuration data, control programs and other important data real-time backup and regular backup measures; for DCS system applications having high data security requirements, it may take measures of complete backup of the system normal operation data, the backup period shall be not more than 3 months; for the DCS system applications having higher data security requirements, it may establish remote disaster backup center with communication lines, network equipment and data processing equipment required for disaster recovery.

4.2.2 System protection principles

In the industrial control system area, industrial control systems emphasize the intelligent control, monitoring and management of industrial automation processes and related equipment. They are quite different from common IT information systems in terms of system architecture, equipment operating system, data exchange protocol and the like. It pays more attention to the system real-time and business continuity. In other words, the industrial control Technical protection mainly refers to the use of technical means to perform DCS security protection, such as access control, border management, pipeline communication, etc. Before the application of protection technology, strict system test shall be carried out on the same DCS system by means of offline test to avoid the availability, real-time, reliability and security of normal DCS operation from affected after being on-line; if there is significant risk which affects system availability, real-time, reliability and security, the deployment of protective software which affects the system is revoked.

d) The principle of defense in depth A single security product, technology, or solution cannot protect DCS effectively, so a multi-layered protection strategy with two or more different mechanisms is needed. […]