Statistical Data Fingerprinting for Document Similarity Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current data loss prevention methods struggle to accurately categorize and compare portions of text within documents, as trivial changes can evade detection through simple hashing methods.

Innovation Solution

A computer-implemented method of statistical data fingerprinting that generates fingerprints by applying a statistical function measuring randomness of characters in subsets of text against an expected distribution, allowing for precise matching between document subsets using Euclidean, rectilinear, or Shannon entropy metrics.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If simple block-hashing is used to compare documents or portions of documents, then the process is computationally efficient and simple, but trivial changes to the data can evade detection

Engineering Contradiction:
Improvesimplicity of hashing processVSAvoiddetection accuracy
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The patent divides documents into multiple portions or segments and applies hashing to each segment individually. This segmentation allows the system to detect changes in specific portions without requiring complete document matching, thereby improving detection accuracy while maintaining computational efficiency through localized processing.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent employs multiple hashing algorithms with different parameters (e.g., MD5, SHA-1, SHA-256) and varies the segmentation parameters such as segment size and overlap. By changing these parameters dynamically, the system adapts to different document types and change patterns, enhancing detection reliability without sacrificing the simplicity of the underlying hashing mechanism.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If whole documents are classified and compared, then complete document similarity can be determined, but identifying and comparing specific portions of user data within documents remains challenging

Engineering Contradiction:
Improvedocument similarity accuracyVSAvoidportion identification complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent automatically segments documents into meaningful portions based on delimiters, data types, or predefined rules. This segmentation enables the system to compare specific portions independently while maintaining the context of the whole document, thus achieving precise portion-level similarity measurement without manual intervention or complex analysis.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent creates a universal hashing framework that can operate at multiple levels: individual portions, combinations of portions, or entire documents. This multi-functional approach allows the same system to handle both granular portion comparison and holistic document comparison, reducing complexity by avoiding separate systems for different comparison scopes.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Reliability

If statistical functions measuring randomness are applied to subsets of text, then accurate matching and change detection can be achieved, but the computational complexity increases compared to simple hashing

Engineering Contradiction:
Improvechange detection accuracyVSAvoidstatistical analysis complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies statistical randomness measurements selectively to specific portions of text that are suspected of containing sensitive or change-prone data. Rather than analyzing entire documents uniformly, the system focuses computational resources on critical segments, thereby achieving high detection accuracy while minimizing overall computational complexity through localized analysis.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent implements a two-stage approach where simple hashing is first applied to all document portions for quick comparison, and statistical randomness analysis is applied only to portions that show potential mismatches or contain sensitive data. This partial application of complex analysis reduces overall computational burden while maintaining high detection accuracy for critical changes.

Inventive Principle:
Principle #16Partial or excessive action

Data Source

PatentUS11430244B2Statistical data fingerprinting and tracing data similarity of documents
Publication Date: 2022.08.30 CYLANCE INC
  • US11430244B2 patent drawing
  • US11430244B2 patent drawing
  • US11430244B2 patent drawing

AI summary

A method and computing device for statistical data fingerprinting and tracing data similarity of documents. The method comprises applying a statistical function to a subset of text in a first document thereby generating a first fingerprint; applying the statistical function to a subset of text in a second document thereby generating a second fingerprint; comparing the first fingerprint to the second fingerprint; and determining that the subset of text in the first document matches the subset of text in the second document based on the first fingerprint threshold matching the second fingerprint, wherein the statistical function is a measure of randomness of a count of each character in a subset of text against an expected distribution of said characters.