A fine-grained message clustering method based on message representation and identifier fingerprints

Protocol reverse engineering is a critical technique for analyzing private protocols and unknown protocols. Message clustering is a foundational element of protocol reverse engineering, playing a key role in traffic classification and format inference. In this paper, we propose a fine-grained unknown message clustering method, termed FG-MCRF. FG-MCRF extracts deep representation vectors from the raw message data by constructing a representation network with low information loss and constructs high-purity message clusters based on representation vectors. The FG-MCRF method constructs high-precision global message fingerprints for each message cluster based on message length identifiers, operation identifiers, and counter identifiers. Subsequently, FG-MCRF constructs a message relationship graph based on these global message fingerprints and determines the final message type using the relationship graph. We also introduce the fine-grained multi-protocol dataset (FgMPD) to evaluate the clustering performance of our method. The experimental results demonstrate that the FG-MCRF methodology achieves superior clustering performance on the FgMPD dataset, outperforming other baseline methods. The clustering purity, Adjusted Rand Index (ARI), completeness, and accuracy of FG-MCRF in the fine-grained message clustering task are 0.9961, 0.9897, 0.9837, and 0.9899, respectively, representing improvements of 3.2%, 10.5%, 10.9% and 8.7% compared to state-of-the-art (SOTA) baseline methods. These results indicate that the FG-MCRF method possesses robust generalization capacity and extensibility, facilitating fine-grained message clustering.