LSNCP: Lightweight and Secure Numeric Comparison Protocol for Wireless Body Area Networks

Wireless body area networks (WBANs) have been deployed in numerous applications, where the most common communication technology is Bluetooth. Bluetooth uses the numeric comparison protocol (NCP) to negotiate session keys based on the elliptic curve cryptography (ECC) and Out-of-Band (OoB) channels. However, the scalar multiplication of ECC is a heavy computing operation for devices in WBANs. To address this issue, we propose the lightweight and secure NCP (LSNCP) which requires less scalar multiplication than the NCP in Bluetooth. New logic expressions and rules are proposed to verify the security of LSNCP in GNY logic. The proof shows that LSNCP is secure. We conduct a provable security analysis by integrating the commitment scheme and short hash function. The result shows that LSNCP is secure in the modified Bellare-Rogaway model. Finally, we conduct theoretical analysis and experiments to evaluate the performance of LSNCP. The results confirm that LSNCP has less computation cost than NCP and other benchmark protocols. LSNCP has many potential application scenarios, such as healthcare, Metaverse, and blockchain.