Intrusion Tolerance for Unclassified Networked Systems

Abstract : Information such as security advisories, emergency recommendations, e-government information, etc., is unclassified, but its availability and integrity may be vital. Such data are intended to be made widely available and thus need to be accessible through open networks such as the Internet. The systems distributing this kind of information are usually built from COTS hardware and software, since their functions do not require specific software or hardware development. Openness and use of COTS make these systems very vulnerable, and traditional security means are insufficient to achieve the required availability and integrity. In that case, fault tolerance can be viewed as a complementary, valuable technique to cope with possible intrusions, as well as accidental failures of system components. This paper presents the techniques of intrusion tolerance, and describe some recent experimental architectures, developed by the European project MAFTIA and the DARPA project DIT.