Dynamic Protocol Parse Based on a General Protocol Description Language

Real-timenetwork protocol data are indispensable for network security analysis. However, the rapid evolution of protocol standards poses significant challenges to automated parsing and dynamic extensibility. While artificial intelligence (AI) techniques offer potential solutions, they often introduce semantic ambiguities and inconsistent results, thereby undermining parsing precision. To overcome these limitations, we propose PMDL (Protocol Model Description Language), a general-purpose protocol description language. PMDL abstracts protocols into structured sets of fields and attributes, enabling precise and unambiguous specification of protocol syntax and semantics. Based on PMDL descriptions, our execution engine dynamically instantiates and loads protocol templates on the fly, achieving accurate, automated, and dynamically extensible parsing of network traffic. We evaluate PMDL against representative tools such as Wireshark and Kelai, as well as approaches such as Nail and BIND. Experimental results demonstrate that PMDL provides concise yet expressive protocol specifications, and the execution engine achieves superior parsing throughput. Furthermore, performance evaluation using real-world HTTP, MySQL, and DNS traffic from a campus network confirms that our system robustly meets the throughput requirements of large-scale security analysis.