Power Supply Segmentation for Secured Functional Units
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Industrial electrical apparatuses are vulnerable to attacks that increase power consumption of unsecured functional units, potentially disrupting the power supply to secured units, compromising the entire system.
Innovation Solution
The electrical apparatus employs separate supply units and power paths for secured and unsecured functional units, with a power limiting device and switch in the power path to the unsecured unit, ensuring that an attack only affects the unsecured unit and maintaining sufficient power for the secured unit.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single supply device powers both secured and unsecured functional units, then device complexity is reduced, but the secured functional unit becomes vulnerable to power disruption attacks through the unsecured unit
Solution Approach 1:
The power supply system is segmented into separate power paths: a first power path supplies the secured functional unit while a second power path supplies the unsecured functional unit. This segmentation isolates the secured unit from attacks on the unsecured unit, resolving the vulnerability without requiring complete system separation.
Solution Approach 2:
A current limiter is introduced as an intermediary component in the second power path between the supply device and the unsecured functional unit. This intermediary restricts the maximum current that can be drawn through the unsecured unit, preventing it from overwhelming the supply device and disrupting the secured unit's operation.
2Adaptability or versatility
If the unsecured functional unit can draw unlimited power, then its operational flexibility is improved, but it can compromise the secured functional unit by consuming excessive power
Solution Approach 1:
The current limiter is pre-configured in the second power path to enforce a maximum current threshold before any attack occurs. This preliminary restriction prevents the unsecured unit from drawing excessive power that could harm the secured unit, while still allowing normal operational flexibility within the established limits.
3Reliability
If separate supply units are used for secured and unsecured functional units, then security is improved, but device complexity and cost increase
Solution Approach 1:
The power distribution is segmented into distinct power paths with separate current limiting mechanisms for each functional unit type. This segmentation achieves security isolation while maintaining a unified supply device architecture, avoiding the need for completely separate supply units.
Solution Approach 2:
Current limiting protection is applied locally only to the second power path serving the unsecured functional unit, rather than implementing separate supply units throughout the entire system. This localized approach provides necessary security while minimizing overall system complexity.
Data Source
AI summary
An electrical apparatus includes a secured functional unit, an unsecured functional unit and a supply device. The secured functional unit has a first interface device for secure communication and a control unit, and the unsecured functional unit has a second interface device for non-secure communication. The secured functional unit and the unsecured functional unit are designed for communicating with one another. The supply device further includes a supply unit. A first power path for supplying the secured functional unit is arranged between the supply unit and the secured functional unit, and a second power path for supplying the secured functional unit with electrical energy from the supply unit is arranged between the supply unit and the unsecured functional unit. A switch is arranged in the second power path. A second power path in the switch is looped in the first switching state and disconnected in the second switching state.