Reinhardt: Real-time Reconfigurable Hardware Architecture for Regular Expression Matching in DPI

Regular expression (regex) matching is an integral part of deep packet inspection (DPI) but a major bottleneck due to its low performance. For regex matching (REM) acceleration, FPGA-based studies have emerged and exploited parallelism by matching multiple regex patterns concurrently. However, even though guaranteeing high-performance, existing FPGA-based regex solutions do not still support dynamic updates in run time. Hence, it was inappropriate as a DPI function due to frequently altered malicious signatures. In this work, we introduce Reinhardt, a real-time reconfigurable hardware architecture for REM. Reinhardt represents regex patterns as a combination of reconfigurable cells in hardware and updates regex patterns in real-time while providing high performance. We implement the prototype using NetFPGA-SUME, and our evaluation demonstrates that Reinhardt updates hundreds of patterns within a second and achieves up to 10 Gbps throughput (max. hardware bandwidth). Our case studies show that Reinhardt can operate as NIDS/NIPS and as the REM accelerator for them.