Circuit Assembly Key Generation via Signal Superposition
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current cryptographic methods, especially for nodes with limited resources like sensors and actuators, face challenges in generating secure symmetrical keys due to high computational complexity and complex key management, particularly in networked systems like CAN-based vehicle networks.
Innovation Solution
A method for generating a shared secret symmetrical cryptographic key between two nodes in a network using a public exchange of data over a shared transmission medium, where participants transmit logical bit sequences as physical signals, allowing for automated and secure key establishment with low complexity and energy requirements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If asymmetric cryptographic methods are used, then security is improved, but computational complexity increases significantly
Solution Approach 1:
The patent replaces complex computational cryptographic operations with physical layer signal processing. Nodes transmit random bit sequences through the physical transmission medium and use physical signal superposition properties to generate shared secret keys, eliminating the need for computationally intensive asymmetric cryptographic algorithms while maintaining security.
Solution Approach 2:
The transmission medium itself is utilized to generate the cryptographic key material. The physical properties of the medium (signal superposition, attenuation, noise) automatically create randomness and secret information during normal data transmission, eliminating the need for separate key generation processes and reducing computational overhead.
2Reliability
If manual key management is implemented, then key security is maintained, but operational complexity increases
Solution Approach 1:
The system automatically generates and manages cryptographic keys through physical layer processes. Nodes independently generate random bit sequences, transmit them through the medium, and automatically derive shared secret keys using the physical properties of the transmission channel, eliminating manual key distribution and management operations.
Solution Approach 2:
Random bit sequences are generated and transmitted in advance during normal communication operations. The key material is prepared and exchanged through the physical medium before cryptographic operations are needed, allowing keys to be readily available when required without manual intervention.
3Stability of the object's composition
If keys are generated centrally, then key consistency is ensured, but system scalability is limited
Solution Approach 1:
The key generation process is distributed to individual nodes rather than centralized. Each node independently generates its own random bit sequences and participates in the key derivation process using the physical transmission medium, allowing the system to scale to any number of nodes without requiring centralized key management infrastructure.
Solution Approach 2:
The physical transmission medium serves multiple functions: it carries both data traffic and cryptographic key material simultaneously. The same communication channel used for normal operations is also utilized for key generation, eliminating the need for separate centralized key distribution systems and enabling seamless scalability.
4Reliability
If asymmetric key exchange is performed, then security is enhanced, but transmission bandwidth consumption increases
Solution Approach 1:
The patent combines data transmission and key exchange into a single process. Random bit sequences used for key generation are transmitted alongside or integrated with normal data traffic through the same physical medium, utilizing the inherent randomness of the transmission channel rather than requiring separate dedicated key exchange channels.
Solution Approach 2:
Complex asymmetric key exchange protocols are replaced with simple physical layer signal transmission. Nodes transmit random bit sequences through the medium and use physical signal properties to derive keys, reducing bandwidth consumption from thousands of bits in traditional asymmetric exchange to minimal overhead for transmitting random sequences.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a method for generating a key in a first circuit assembly, in particular a microcontroller. The first circuit assembly initiates a transmission of at least one first value sequence on a transmission channel at least partly synchronously with the transmission of at least one second value sequence by a second circuit assembly. The first circuit assembly ascertains a secret element for generating the key on the basis of the at least one first value sequence and on the basis of the superposition of the at least one first value sequence and the at least one second value sequence on the transmission channel. The first circuit assembly is monitored for errors.