re facinating facts bit serial number possibly fixed s and s in article pmetzger apr snark shearson com pmetzger snark shearson com perry e metzger writes hmmm we must assume that generating the unit key u from the serial number n rather than generating it from a randomly selected u and u is an intentional way of assuring a fail safe for the government u is completedly determined given s s and n if s and s do not change even if they remain secret i wonder if they can somehow be back derived given enough unit key serial number pairs maybe such pairs suffice to reconstruct s and s by such a back door in the encryption algorithm perhaps it would be possible for the manufacturer to get the keys of all chips that were programmed in one session this would not btw enable anybody else to retrieve the keys in the same way because they ll never get a bunch of n u pairs with identical s and s note that these have to be constant for the whole batch by the very nature of the procedure i e they have to be typed in manually by the random number supplying agents and i was wondering why they ll always do chips in one session since the procedure described by ms denning imposes high costs on the production of every chip at least three persons for one hour each plus the cost of a laptop finally blown to pieces in a spectacular hollywood like bonfire add travelling expenses drinks and lighting divide the sum by there won t be a larger demand not from the private sector anyway and let me mention one other thought that certainly has occurred to all the notoriously paranoid people in this group before who is going to verify that no interested party will perform tempest attacks on the vault where there s so much smoke and mirrors there can t be a nice honest fire but something really worth hiding detlef lannert dc ek e mail tsos rz uni duesseldorf de pgp key via server or finger lannert clio rz uni duesseldorf de i am psmith oh you re smith are you with a preliminary p which however is not sounded p g wodehouse
