Anti-spoofing: Integrated information authentication of BeiDou-II civil navigation message

The BeiDou-II civil navigation message (BDII-CNAV) is transmitted in an open environment and no information integrity protection measures are provided. Hence, the BDII-CNAV faces the threat of spoofing attacks, which can lead to wrong location reports and time indication. In order to deal with this threat, we proposed a scheme of anti-spoofing for BDII-CNAV based on integrated information authentication. This scheme generates two type authentication information, one is authentication code information (ACI), which is applied to confirm the authenticity and reliability of satellite time information, and the other is signature information, which is used to authenticate the integrity of satellite location information and other information. Both authentication information is designed to embed into the reserved bits in BDII-CNAV without changing the frame structure. In order to avoid authentication failure caused by public key error or key error, the key or public key prompt information (KPKPI) are designed to remind the receiver to update both keys in time. Experimental results indicate that the scheme can successfully detect spoofing attacks, and the authentication delay is less than 1% of the transmission delay, which meets the requirements of BDII-CNAV information authentication.