A practical network intrusion detection system for inline FPGAs on 10GbE network adapters

A network intrusion detection system (NIDS), such as SNORT, analyzes incoming packets to identify potential security threats. Pattern matching is arguably the most important and most computationally intensive component of a NIDS. Software-based NIDS implementations drop up to 90% of packets during increased network load even at lower network bandwidth. We propose an alternative hybrid-NIDS that couples an FPGA with a network adapter to provide hardware support for pattern matching and software support for post processing. The proposed system, SFAOENIDS, offers an extensible open-source NIDS for Solarflare AOE devices. The pattern matching engine-the primary component of the hardware architecture was designed based on the requirements of typical NIDS implementations. In testing on a real network environment, the SFAOENIDS hardware implementation, operating at 200 MHz, handles a 10Gbps data rate without dropping packets while simultaneously minimizing the server CPU load.