Cryptography – Particular algorithmic function encoding – Nbs/des algorithm
Patent
1990-07-24
1992-12-01
Gregory, Bernarr E.
Cryptography
Particular algorithmic function encoding
Nbs/des algorithm
380 28, 380 37, H04L 906
Patent
active
051685213
ABSTRACT:
This method of processing data protected by encryption is particularly suitable for smart cards utilizing the DES system. The method enables the execution of the irregular permutation of the key on the basis of a correspondence table, which operation is most costly as regards processing time and code length in the cited system. The method involves the decomposition of the initial permutation into a plurality of elementary permutations so that the majority thereof is performed on at least two bits, the bits of the various octets of the key being marked, a masking system being applied in order to extract the appropriate bits for their permutation in the positions predetermined by the correspondence table.
REFERENCES:
patent: 4255811 (1981-03-01), Adler
patent: 4536647 (1985-08-01), Atalla et al.
patent: 4816651 (1989-03-01), Ishording
"Software Data Encryption Standard" IBM Technical Disclosure Bulletin, vol. 29, No. 12, May 1987, pp. 5594-5595.
"Data Encryption Standard" FIPS PUB 46, Jan. 15, 1977.
"Data Encryption Standard" FIPS PUB 46-1, Jan. 22, 1988.
Delaporte Xavier
Leterrier Benoit
Gregory Bernarr E.
Slobod Jack D.
U.S. Philips Corp.
LandOfFree
Method of executing an irregular permutation of data protected b does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of executing an irregular permutation of data protected b, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of executing an irregular permutation of data protected b will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-507806