Control System Client Integrity Checks for Manipulation Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing client server architectures in control systems of technical plants lack robust protection against code manipulation, leading to potential operational disruptions and damage due to undetected manipulations, with no effective mechanisms for immediate detection and rehabilitation.
Innovation Solution
A method involving asymmetric key pairs and cryptographic hash functions is employed to verify the integrity of code executed in clients, ensuring secure communication by encrypting and signing secret keys and hash values, allowing immediate detection and rehabilitation of manipulated clients.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If code is loaded into the operator station client without protection mechanisms, then ease of operation is improved, but reliability deteriorates due to potential undetected manipulations
Solution Approach 1:
The system performs preliminary integrity verification of the code before execution by calculating a hash value of the downloaded code and comparing it with a hash value stored in a protected area of the client. This preliminary check ensures that any manipulation is detected before the code can cause harm, thus maintaining reliability while allowing ease of operation.
2Reliability
If manipulation detection mechanisms are implemented, then reliability is improved, but device complexity worsens due to additional security protocols
Solution Approach 1:
The invention extracts the integrity verification logic into a separate, dedicated mechanism that operates independently from the main code execution flow. The hash calculation and comparison are performed as distinct steps, separating the security function from the operational code, which manages complexity while maintaining reliability.
Solution Approach 2:
The patent introduces an intermediary hash value comparison mechanism that acts as a mediator between the downloaded code and the execution environment. Instead of complex direct verification, the hash value serves as an intermediary representation that simplifies the integrity check while ensuring reliability.
3Reliability
If manipulated code is rejected immediately upon detection, then reliability is improved, but productivity deteriorates due to operational interruptions
Solution Approach 1:
The system dynamically responds to manipulation detection by transitioning the client into a restricted mode rather than immediately terminating operations. The affected client is prevented from further communication with the control system, allowing for controlled rehabilitation while maintaining overall system reliability and minimizing productivity impact.
Data Source
AI summary
A client-server architecture for a control system of a technical installation, wherein the client-server architecture includes at least one first device formed as a client and at least one second device that formed as a server assigned to the client, where the client is configured to establish contact with the server, and is configured to execute a code received from the server, communication from the client to the control system exists via the server which is configured to detect whether the code, which the client executes, corresponds to the code that the client received from the server, and where the server, in the event of the code not corresponding, is further configured to interrupt the execution of the code by the client and lock the client out of communication with the control system.