CardGuard is a signature detection system for intrusion detection and prevention that scans the entire payload of packets for suspicious patterns and is implemented in software on a network card equiped with an Intel IXP1200 network processor. One card can be used to protect either a single host, or a small group of machines connected to a switch. CardGuard is non-intrusive in the sense that no cycles of the host CPUs are used for intrusion detection and the system operates at Fast Ethernet link rate. TCP flows are first reconstructed before they are scanned with the Aho-Corasick algorithm.
['Herbert Bos', 'Kaiming Huang']
Towards software-based signature detection for intrusion prevention on the network card