Process and communication system for communicating information protected by encryption between a first station to a second station transmitter / receiver and transmitter / receiver using a network.Control stations, device to encrypt and decrypt signals transmitted between a first and a second station, process to facilitate communications encrypted, direct, a jump.Between a first mobile station and a second mobile station, satellite communications system, and.Process and communication system for establishing communication between a first station transceptora encrypted and a second station transceptora using a network of control stations

摘要

An apparatus and method for ciphering traffic exchanged in both directions between a satellite/cellular telephone and a ground station network using an orbitial satellite. A buffer memory is provided at either the mobile telephone station or the ground network station or both. The buffer memory is used to store the deciphering bits output from a duplex ciphering algorithm at the time the ciphering bits are generated. The stored ciphering bits are used to decipher a later-to-be-received traffic information block. The delay in using stored deciphering bits is determined for each call at call set-up to the nearest integer number of block periods by measuring the loop propagation delay from the ground station to the mobile telephone station during an exchange of signals at call set-up. IMAGE