Telecommunications – Carrier wave repeater or relay system – Frequency or phase modulation
Patent
1981-08-31
1983-11-29
Cangialosi, Sal
Telecommunications
Carrier wave repeater or relay system
Frequency or phase modulation
370104, 375 22, 178 2217, H04K 100, H04J 316
Patent
active
044184255
ABSTRACT:
An encryption system is disclosed which is based on channel destination addresses for a time division multiple access (TDMA) satellite communications network. A superframe initialization vector is transmitted from a master station to all other stations in the network. A plurality of frame initialization vectors is sequentially generated at each station in an encryption engine, from the superframe initialization vector, using a key which is common only to authorized users within the network. Each data channel is initialized with encryption bits produced by exclusive ORing the channel destination address and the frame initialization vector for the frame in which that channel is to be transmitted, and then passing the output of the exclusive OR through the encryption engine using either the same key or a second, different key. These encryption bits are combined with the channel data in an exclusive OR circuit for TDMA transmission via the satellite transponder to the receiving stations. The decryption process at the receiving stations parallels the encryption process at the transmitting stations, so that clear-text data is output only at the destination addressed where the intended recipient has the same key as the transmitter. The system enables the synchronization of encryption engines at separate, geographically remote stations and permits the decryption of encrypted channels at anytime within a TDMA frame.
REFERENCES:
patent: 3798359 (1974-03-01), Feistel
patent: 4135059 (1979-01-01), Schmidt
patent: 4171513 (1979-10-01), Otey et al.
patent: 4255811 (1981-03-01), Adler
patent: 4262356 (1981-04-01), Lautier et al.
patent: 4305152 (1981-12-01), Asakawa et al.
patent: 4315330 (1982-02-01), Brickman et al.
patent: 4319353 (1982-03-01), Alvarez et al.
patent: 4322576 (1982-03-01), Miller
patent: 4346470 (1982-08-01), Alvarez et al.
patent: 4357700 (1982-11-01), Alvarez et al.
S 1792 0125, Int. Conf. on Communications, Denver, Co. (1/14-18/81), pp. 59.4-59.45, "Synchronization Techniques for Mobile Satellite Systems", Hagmann et al.
S 1792 011, Int. Conf. on Comm., Denver, Co. (1/14-18/81), pp. 55.1-55.7, "SS/TDMA Frame Synchonization", Campanella et al.
S 0111 0016, Conf. on Electrncs & Aero. Syst., Wash. D.C. (10/69), "Results of TDMA Equip. Dev. Appl. to Military Systems", pp. 133-137 Epstein et al.
Fennel, Jr. John W.
Heinz, Jr. Miles T.
Cangialosi Sal
Hoel John E.
IBM Corporation
LandOfFree
Encryption using destination addresses in a TDMA satellite commu does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Encryption using destination addresses in a TDMA satellite commu, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Encryption using destination addresses in a TDMA satellite commu will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-610611