Image credit: Thomas Jefferson Foundation
The N-Variant Framework
Poster for CyberTrust PIs Meeting
[PNG, JPG, PDF]
28 September 2005
The first property means that adversaries can have complete knowledge about the structure and software of our systems without compromising their security. Thus, insider snooping cannot defeat our vulnerability protection against outsider initiated attacks, and probing or guessing attacks that have been shown effective against previously proposed diversity techniques pose no threat to our system.
The second property means that there can be a high level of assurance in the coverage of vulnerabilities in the system based on formal arguments and depend only on clearly stated assumptions about components of our system structure, but place no constraints on properties of the protected software service.
An instantiation of our idea is the N-Variant System Framework, which provides a general mechanism for detecting and preventing classes of attacks on vulnerable servers. The framework consists of:
N-Variant Systems: A Secretless Framework for Security through Diversity
Benjamin Cox, David Evans, Adrian Filipi, Jonathan Rowanhill, Wei Hu, Jack Davidson, John Knight, Anh Nguyen-Tuong, and Jason Hiser. 15th USENIX Security Symposium, Vancouver, BC, August 2006. (PDF, 16 pages; HTML)
Talk slides: [PPT], PDF]
N-Variant Systems: A Secretless Framework for Security through Diversity [PPT], PDF] (Benjamin Cox). USENIX Security Symposium, Vancouver, BC, 3 August 2006.
N-Variant Systems: A Secretless Framework for Security through Diversity [PPT, PDF] (David Evans). Seminar talk at Beijing Institute of Technology, 30 May 2006.
N-Variant Systems: A Secretless Framework for Security through Diversity [PPT, PDF] (David Evans). Seminar talk at Institute of Software, Chinese Academy of Sciences, Beijing, 29 May 2006.
Promising Breaks and Breaking Promises: Program Analysis in Theory and Practice [PPT, PDF] (David Evans). 90-minute class at SDWest 2006, 17 March 2006. Incoporates slides from a talk by Jinlin Yang.
The N-Variant Systems Framework: Polygraphing Processes for Secretless Security [PPT, PDF] (David Evans). Colloquim at University of Texas at San Antonio, 4 October 2005.
Polygraphing Processes: N-Variant Systems for Secretless Security [PPT] (David Evans). DARPA SRS PIs Meeting, Alexandria, VA. 12 July 2005.
Stealing Secrets and Secretless Security Structures [PPT] (David Evans). Colloquium at Harvard University. 27 June 2005.
Security Through Diversity [PPT] (David Evans). Colloquim at MIT CSAIL. 23 June 2005.
An excerpt is available on Bruce Schneier's blog: Security and Monoculture
University of Virginia
Department of Computer Science
Security Research Group