Patent ID: 8824681

Claim:
A method of decrypting and encrypting link layer encrypted (LLE) and end-to-end encrypted (eTe) voice message streams at a wireless communications device, the method comprising: receiving, by the wireless communications device, one of a header and a data unit of a voice message stream, the one of the header and the data unit including an LLE encryption initialization vector embedded therein; retrieving,by the wireless communications device, the LLE encryption initialization vector from the one of the header and the data unit; using, by the wireless communications device, the retrieved LLE encryption initialization vector to link layer decrypt both (i) the one of the header and the data unit and (ii) a subsequent data unit of the voice message stream following the one of the header and the data unit; recovering, by the wireless communications device, eTe encryption parameters in the one of the header and the data unit for decrypting eTe encrypted voice payloads in one or more subsequent data units in the voice message stream; and forwarding, by the wireless communications device, the eTe encryption parameters and voice payloads towards their destination.