Navigation Message Authentication Based on One-Way Hash Chain to Mitigate Spoofing Attacks for GPS L1

Global Navigation Satellite Systems (GNSS) is vulnerable to significant threats such as spoofing attacks. Data and signal authentication can be used as an effective approach to mitigate such security threats. This paper proposes a Navigation Message Authentication (NMA) method based on Timed Efficient Stream Loss-tolerant Authentication (TESLA), which is using one-way encryption chains. The contributions of this paper are two techniques for implementing TESLA using reserved bits for GPS L1 data. The TESLA algorithm is applied to the extracted navigation message of the GPS L1C/A. Due to the flexibility of the GPS L1C message structure, the protocol is also implemented on Civil Navigation signals (CNAV-2) of GPS L1C. In comparison with Elliptic Curve Digital Signature Algorithm (ECDSA), the Authentication Rate (AR) increases to two minutes for each authentication and performance in term of the Authentication Error Rate (AER) is optimized, by using the TESLA method.