QKD Privacy Amplification Using Pre-Defined Bit Mapping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional QKD post-processing methods, particularly privacy amplification, suffer from high computational complexity due to large data strings, leading to inefficient throughput and increased processing time.
Innovation Solution
A device and method that generate a pre-defined map based on the information reconciliation scheme to reduce the input length for privacy amplification, using parity-check and generator matrices to identify a compact signature, and apply a one-to-one mapping to extract a shorter output data string for privacy amplification.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional privacy amplification is performed on the full error corrected data string, then security is maintained, but computational complexity increases and throughput decreases
Solution Approach 1:
The patent extracts only the necessary portion of the error corrected data string for privacy amplification by applying a pre-defined map that identifies which bits contain information about the secret key. This extraction principle reduces the input size to privacy amplification while maintaining security, directly resolving the contradiction between throughput and computational complexity.
Solution Approach 2:
The patent segments the error corrected data string into different portions: bits that are directly used for key generation and bits that are used for syndrome calculation. By applying the map to identify and process only the relevant segments, the system achieves higher throughput without compromising security, as each segment is processed appropriately.
2Loss of time
If the full error corrected data string is used as input to privacy amplification, then all information is processed, but processing time increases
Solution Approach 1:
The map extracts only the essential bits from the error corrected data string that contain information about the secret key. This extraction ensures that no critical information is lost while significantly reducing the processing time required for privacy amplification, as the function operates on a smaller, optimized input set.
Solution Approach 2:
The pre-defined map is prepared in advance based on the information reconciliation scheme, performing preliminary identification of which bits are relevant for key generation. This preliminary action eliminates the need for complex real-time analysis during privacy amplification, reducing processing time while preserving information completeness.
3Reliability
If a larger randomness string is used for privacy amplification, then security is enhanced, but resource requirements increase
Solution Approach 1:
The patent extracts only the essential randomness requirements by applying the map to identify the minimum number of random bits needed for secure key generation. This approach maintains security by ensuring sufficient randomness is used while minimizing resource consumption, directly addressing the contradiction between security and randomness resource requirements.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present disclosure provides a device for processing data of a Quantum Key Distribution (QKD) system. The device is configured to obtain a pre-defined map based on an information reconciliation scheme; apply the obtained map to an error corrected data string to generate an output data string, the output data string being shorter than the error corrected data string; and perform privacy amplification on the output data string.