Protocol Identification via Statistical Classification
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for identifying the protocol at the origin of a data stream, particularly in encrypted or encapsulated flows, suffer from a high number of false positives, making it difficult to enforce security policies effectively in network security systems.
Innovation Solution
A method involving two phases of statistical classification: a global phase using Random Forest algorithms to extract and process parameters like packet size and inter-packet times, and a sequential phase employing hidden Markov models to analyze the temporal chaining of packets, followed by a synthesis step using Bayes' formula to determine the protocol, with an additional filtering step based on historical data and heuristic analysis to reduce false positives.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If statistical classification methods are used to identify protocols in encapsulated flows, then protocol detection capability is improved, but the number of false positives increases
Solution Approach 1:
The patent divides the classification task into two distinct phases: global statistical classification using Random Forest algorithms and sequential classification using Hidden Markov Models. Each phase processes different aspects of the data stream independently, with the global phase capturing overall statistical patterns and the sequential phase analyzing temporal dependencies. This segmentation allows the system to leverage the strengths of each method while mitigating their individual weaknesses, thereby improving detection accuracy without proportionally increasing false positives.
Solution Approach 2:
The patent merges the results from two different classification approaches (Random Forest and Hidden Markov Models) through a synthesis step that combines their outputs. By integrating multiple classification perspectives, the system achieves more robust protocol identification that is less susceptible to false positives from any single method. The combination of global statistical features and sequential temporal patterns creates a more reliable detection mechanism.
2Measurement precision
If in-depth inspection of packet contents is performed to identify protocols, then detection accuracy is improved, but system complexity and processing time increase
Solution Approach 1:
The patent extracts and utilizes specific statistical features from packet flows without performing complete in-depth inspection of all packet contents. By focusing on key statistical parameters and temporal patterns rather than analyzing every byte of encrypted or encapsulated data, the system achieves effective protocol identification with reduced computational complexity. This extraction approach avoids the need for complex decryption or deep packet inspection while maintaining detection capability.
Solution Approach 2:
The patent replaces traditional mechanical packet inspection methods with statistical classification algorithms. Instead of manually examining packet contents or using rule-based inspection, the system employs machine learning models (Random Forest and Hidden Markov Models) that automatically learn and identify protocol patterns from statistical features. This substitution reduces system complexity while improving detection accuracy through automated pattern recognition.
3Device complexity
If a single classification method is used to identify protocols, then system simplicity is maintained, but detection accuracy and reliability decrease
Solution Approach 1:
The patent segments the classification process into two specialized phases, each handling different aspects of protocol identification. The global classification phase processes overall statistical characteristics, while the sequential classification phase analyzes temporal patterns. This segmentation allows each phase to be optimized for its specific function, improving overall detection accuracy while maintaining manageable system complexity through clear separation of concerns.
Solution Approach 2:
The patent creates a multi-functional classification system that can handle both global statistical patterns and sequential temporal dependencies within a unified framework. The two-phase classification approach serves multiple purposes: the global phase captures broad protocol characteristics, while the sequential phase identifies temporal patterns. Together, they provide comprehensive protocol detection capability that surpasses single-method approaches.
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
Method of identifying a protocol at the origin of a data flow. The method of identifying a protocol giving rise to a packet flow comprises the following steps: - a capture (102) of the flow of the protocol to be identified, - statistical classification of the flow, comprising an extraction of the classification parameters and a comparison of the classification parameters with statistical models constructed during a learning phase. The statistical classification comprises: - a first phase (108) of global statistical classification; and - a step (120) of synthesis of the results of the first and second classification phases (108, 110) so as to identify the protocol giving rise to the flow.