Abstract:Risk analyses performed by several space agencies have provided indications of the impact of different threats on several categories of space missions in the context of space communication. A method of integrating the GCM (Galois/Counter Mode) into data link layer of Telecommand protocol is proposed after the performance analysis of various AEAD (Authenticated Encryption with Associated Data) techniques. The simulation framework of CCSDS Telecommand systems is designed and implemented with OPNET. The simulation results show, AEAD techniques can effectively provide the confidentiality, integrity and authentication of Telecommand information with no decrease to the throughput performance.