Research on End-to-End Encryption of TETRA

The Terrestrial Trunked Radio (TETRA) system uses end-to-end encryption in addition to the air interface encryption to provide enhanced security. The TETRA system uses a synchronization technique known as frame stealing to provide synchronization of end-to-end encrypted data. However, the frame stealing process degrades the quality of video. This paper proposes an end-to-end encryption system with the frame stealing technique for voice and frame insertion for video. A block cipher in the output feedback mode is used to implement the end-to-end key stream generator. Moreover. In the Short Data Service (SDS) message encryption, a block cipher in the Cipher Block Chaining (CBC) mode is used to calculate the cryptographically secure checksum, which is sufficient to certify the integrity.