Fred Cohen


In part 1 of this series (Cohen, 2011a), we discussed some of the basics of building a physics of digital information. Assuming, as we have, that science is about causality and that a scientific theory should require that cause(C) produces effect (E) via mechanism M (written C→ME), we explore that general theory of digital systems from the perspective of attributing effects (i.e., traces of activities in digital systems) to their causes. Full details of the current version of this physics are available online2 , and in this article, we explore a few more of them.


Backes, M., Kopf, B., & Rybalchenko, A. (2009). Automatic Discovery of Quantification of Information Leaks. In Proceedings of the 30th IEEE Symposium on Security and Privacy, May 17-20, 2009, Berkeley, CA. Los Alamitos, CA: IEEE.

Cohen, F. (2010). Toward a Science of Digital Forensic Evidence Examination. IFIP TC11.8 International Conference on Digital Forensics, Hong Kong, China, January 4, 2010. In K.-P. Chow and S. Shenoi (eds.), Advances in Digital Forensics VI, Springer, pp. 17-36.

Cohen, F. (2011a). Digital Forensic Evidence Examination. Livermore, CA: ASP Press.

Cohen, F. (2011b). Putting the Science in Digital Forensics. Journal of Digital Forensics, Security and Law, 6(1), 7-14.

Cohen, F. (2011c). The Physics of Digital Information. Journal of Digital Forensics, Security and Law, 6(3), 11-16.

Cohen, F. (2012). Update on the State of the Science of Digital Evidence Examination. Submission to the 2012 Conference of Digital Forensics, Security and Law.

Hamilton, E. (1992, September 1). JPEG File Interchange Format, Version 1.02. Milpitas, CA: C-Cube Microsystems. Retrieved from http://www.jpeg.org/public/jfif.pdf

Mealy, G. (1955). A Method for Synthesizing Sequential Circuits. Bell Systems Technical Journal, 34, 1045–1079.

Moore, E.F. (1956). Gedanken experiments on sequential machines. In Automata Studies. Princeton, N. J.: Princeton University Press, pp. 129-153.





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