Abstract: A method and system for menuing on a voice response unit (VRU) or the like that avoids creating customer confusion on low volume calls that results in customer service representatives having to spend time clearing up that confusion without otherwise adversely affecting the system. For example, a menu for non-bankruptcy reaffirmation account and the like is included in the menus of a credit card VRU system. The menu and its sub-menus eliminate the options of balance transfers and credit limit increases that are inapplicable to those customers and result in an inordinate number of lengthy conversations.

Abstract: A method and system for menuing on a voice response unit (VRU) or the like that avoids creating customer confusion on low volume calls that results in customer service representatives having to spend time clearing up that confusion without otherwise adversely affecting the system. For example, a menu for non-bankruptcy reaffirmation account and the like is included in the menus of a credit card VRU system. The menu and its sub-menus eliminate the options of balance transfers and credit limit increases that are inapplicable to those customers and result in an inordinate number of lengthy conversations.

Abstract: Method for changing a previously assigned personal identification number using a voice response unit. The method includes receiving a new personal identification number input by a user interacting with the voice response unit, determining whether the new personal identification number is valid, and changing the previously assigned personal identification number to the new personal identification number without requiring the user to input the previously assigned personal identification number if the new personal identification number is valid.

Abstract: In a receiver (100), an encrypted communication (104) is decrypted using a decryptor (101) and a key (107) to produce a decrypted communication (105). A comparator (103) compares decrypted symbol patterns in the decrypted communication against a set of predetermined symbol patterns (108). When the decrypted symbol patterns are distributed non-uniformly relative to the set of predetermined symbol patterns, the receiver is identified as a target of the encrypted communication.

Abstract: A key management system for encryption keys removes the effect of secure communications loss during a rekey period in a secure communications system. Use of key indexes to partition encryption keys into usable subgroups such that during a rekey period, continuous secure communications are maintained throughout the entire secure communications system.

Abstract: Disclosed is a method and apparatus for time companding a digital voice signal wherein, single bits are periodically removed from the digital voice signal, which is then compressed thereby forming a contiguous area of removed bits. A synchronization signal is inserted into this area and the combined signal is transmitted. At the receiver, the synchronization signal is extracted and is used to synchronize the receiver. The digital voice signal is then expanded and the removed bits are predicted and replaced.

Abstract: Disclosed is a synchronous secure communication system wherein an information signal is encrypted in an encryption means. The encrypted signal is compressed to allow the insertion of a synchronization signal, and the combined signals are transmitted. At the receiver, the synchronization signal is extracted and used to synchronize the receiver to the incoming data stream thereby improving receiver sensitivity and range.

Abstract: CVSD modulation is detected by applying a digital signal containing CVSD information to a digital filter that is in the CVSD loop that includes a syllabic filter and a rule circuit. The digital filter includes voltage-operated switches that switch one of two voltages to a resistor network and thereby combine multiplication and digital filtering. The output of the digital filter is the output of the circuit.

Abstract: A digital voice privacy electronic communication system and method provides protection for an information signal. Either a clear voice signal or a scrambled digitized version of the voice signal is selected for transmission. At the receive end of the system a determination that a clear voice signal or a scrambled signal has been sent is made. This information is used to automatically switch the clear audio signal if present to an output circuit or to switch to the output circuit either a regenerated version of the scrambled signal or an unscrambled version of the information signal. The switching is done automatically so that a user does not have to manually select the proper receiver mode in response to reception of a signal, that is, whether the received signal was a clear voice signal or a scrambled signal. At the transmitter the information signal to be scrambled is analog-to-digital converted and the digital signal is then put into a scrambled form.