METHOD TO PROTECT ENCRYPTION KEYS THAT ARE DISTRIBUTED WITHIN A X-ZONE INFRASTRUCTURE
Original Publication Date: 1999-Sep-01
Included in the Prior Art Database: 2002-Sep-04
The system is X-Zone based with a Terrestrial Trunked Radio (TETRA) air interface. Encryption keys for voice activity are sent over-the-air encrypt- ed so that they are not disclosed on the air interface.