For 65 years, most information-theoretic analyses of cryptographic systems have made a mathematical assumption that turns out to be wrong. An interesting read on encryption is less secure than we thought:

Information theory — the discipline that gave us digital communication and data compression — also put cryptography on a secure mathematical foundation. Since 1948, when the paper that created information theory first appeared, most information-theoretic analyses of secure schemes have depended on a common assumption.

Unfortunately, as a group of researchers at MIT and the National University of Ireland (NUI) at Maynooth, demonstrated in a paper presented at the recent International Symposium on Information Theory (view PDF), that assumption is false. In a follow-up paper being presented this fall at the Asilomar Conference on Signals and Systems, the same team shows that, as a consequence, the wireless card readers used in many keyless-entry systems may not be as secure as previously thought.

Larry Hardesty, MIT News Office
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