end users and end-to-end encryption, would yield significantly improved security capabilities in the long term.



See TCSEC Section (U.S. DOD, 1985d).


To appreciate cryptography, note that we do not always understand what ''information" is. Information, in the sense of semantic content, is always in the mind of the beholder and is a combination of ordinary symbols (e.g., "East Wind, Rain") or extraordinary ones (e.g., Wehrmacht beer orders) and some richer context. To differentiate, "data" is an encoding, and "information" is the (always to some degree unknowable) meaning that the encoding may or may not convey to a human observer. With regard to automata, "information" refers to data that alters the behavior of the robots.

For example, the string RDAQN QRHIH FECCA DRSWV KIKSS HSPAX CUBS conveys 34 characters of data to everyone who has "read" access to this transaction but conveys a significant amount of information only to those who know the richer context of cryptosystem and key. Readers are invited to determine the key from the substantial hint that the plaintext is THERE ARE MORE THINGS IN HEAVEN AND EARTH; solutions may be verified by transforming RCVQD ALCFV CLLLL DLSCK KRVKT BRVAO AVUA from data to information.


The security of RSA is not known to be provably equivalent to the problem of factoring the modulus, although that seems to be the best way to attack it.

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