The deployment of intrusion-detection technology on mission-critical and commercial systems shows that perfect detection and immediate mitigation of attacks remain elusive goals. Even systems developed at great cost contain residual faults and vulnerabilities. In practice, emphasis must shift from unattainable ``bulletproof'' systems to intrusion-tolerant system capable of self-diagnosis, repair, and reconstitution, while continuing to provide service to legitimate clients (with possible degradation) in the presence of intrusions.

The Dependable Intrusion Tolerance project seeks to develop a prototype intrusion-tolerant server architecture. The design, which integrates concepts from distributed intrusion detection, fault tolerance, and formal verification, focuses on Web service, though the approach is more general. The system aims to maintain efficient service with high availability (with possibly degraded response times or throughput) and integrity in the face of a variety of attacks.

• LAAS-CNRS (Toulouse, France)

• Alfonso Valdes

• Dr. Steven Cheung

• Automatic Analysis of Firewall and Network Intrusion Detection System Configurations  (2004)
• An Architecture for an Adaptive Intrusion Tolerant Server  (2002)
• The Inquisitive Sensor: A Tactical Tool for System Survivability  (2001)
• Design Assurance Arguments for Intrusion Tolerance
• Combining monitors for run-time system verification