Biblio

We propose a resilience architecture for improving the security and dependability of authentication and authorization infrastructures, in particular the ones based on RADIUS and OpenID. This architecture employs intrusion-tolerant replication, trusted components and entrusted gateways to provide survivable services ensuring compatibility with standard protocols. The architecture was instantiated in two prototypes, one implementing RADIUS and another implementing OpenID. These prototypes were evaluated in fault-free executions, under faults, under attack, and in diverse computing environments. The results show that, beyond being more secure and dependable, our prototypes are capable of achieving the performance requirements of enterprise environments, such as IT infrastructures with more than 400k users.
 

Providers of critical infrastructure services strive to maintain the high availability of their SCADA systems. This paper reports on our experience designing, architecting, and evaluating the first survivable SCADA system-one that is able to ensure correct behavior with minimal performance degradation even during cyber attacks that compromise part of the system. We describe the challenges we faced when integrating modern intrusion-tolerant protocols with a conventional SCADA architecture and present the techniques we developed to overcome these challenges. The results illustrate that our survivable SCADA system not only functions correctly in the face of a cyber attack, but that it also processes in excess of 20 000 messages per second with a latency of less than 30 ms, making it suitable for even large-scale deployments managing thousands of remote terminal units.