Phrase Matching via Hash Set Scoring for Data Leakage Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing data leakage detection methods, such as phrase matching, face challenges in efficiently identifying sensitive phrases amidst noise words, leading to increased computational complexity as more phrases are added, which affects resource requirements and accuracy.

Innovation Solution

A phrase detection system that generates and compares hashes of phrase terms and content terms, using unigram, bigram, and K-gram hashes, along with scoring mechanisms to determine phrase matches, allowing for efficient detection of sensitive phrases even in noisy content.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional phrase matching with state models is used to detect sensitive phrases in noisy content, then phrase detection capability is achieved, but computational complexity increases geometrically as more phrases are added

Engineering Contradiction:
Improvephrase detection capabilityVSAvoidcomputational complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent segments the phrase matching problem into multiple independent hash computations. Instead of using a monolithic state model that processes entire phrases sequentially, the system divides phrases into individual terms and computes hashes for each term independently. These term hashes are then combined using set operations (union, intersection) to determine phrase matches, thereby segmenting the complex matching task into simpler, parallelizable components.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces hash functions as intermediary representations between the original phrase terms and the matching logic. Each phrase term is transformed into a hash value, and the matching process operates on these hash intermediaries rather than the original text. This intermediary layer enables efficient set-based operations and reduces the computational burden of direct string matching, especially when dealing with noisy content.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Adaptability or versatility

If traditional phrase matching with state models is used to handle noisy content, then noise tolerance is achieved, but accuracy decreases due to obfuscation by noise words

Engineering Contradiction:
Improvenoise toleranceVSAvoiddetection accuracy
Core Design Contradiction:
Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The patent applies partial matching by allowing phrase detection even when not all terms are present or when additional noise terms are interspersed. The system computes the union of term hashes for a phrase and then checks if the content's term hashes contain this union as a subset. This partial matching approach tolerates missing terms and extra noise words while still detecting the intended phrase, thereby maintaining accuracy despite noisy content.

Inventive Principle:
Principle #16Partial or excessive action

3Adaptability or versatility

If more phrases are added to the detection system, then coverage of sensitive information increases, but resource requirements increase geometrically

Engineering Contradiction:
Improvephrase coverageVSAvoidcomputational resource requirements
Core Design Contradiction:
Adaptability or versatilityVSUse of energy by moving object

Solution Approach 1:

The patent merges multiple phrase detection tasks into a unified hash-based framework. Instead of maintaining separate state models for each phrase, the system computes term hashes once and reuses them across multiple phrase patterns. The matching logic merges the hash sets of multiple phrases using set operations, allowing the system to handle many phrases simultaneously with linear rather than geometric resource growth.

Inventive Principle:
Principle #5Merging (Combining)

Data Source

PatentUS9342621B1Phrase matching
Publication Date: 2016.05.17 ZSCALER INC
  • US9342621B1 patent drawing
  • US9342621B1 patent drawing
  • US9342621B1 patent drawing

AI summary

Methods, systems, and apparatus, including computer program products, for generating or using augmentation queries. In one aspect, subject phrases for detection in content are identified. Each phrase has a corresponding cardinality of terms. First hash sets for each of the subject phrases are generated, each first hash set including first hashes of bigram term subsets for each of the phrases. Sub-phrase scores for each of the hashes based on the cardinality of each phrase are assigned. The sub-phrase scores a used to detect the subject phrases in hashes of portions of received content. Other implementations of this aspect include corresponding systems, apparatus, and computer program products.