In response to the security and privacy issues associated with sensing devices in contemporary crowd sensing systems, the paper proposes a crowd sensing networks method based on the MFHE (the Multi-Functional Homomorphic Encryption) architecture. This method leverages fully homomorphic encryption technology, thereby eliminating the use of plaintext throughout the sensing process and enhancing security compared to traditional encryption methods. Initially, a sensing model is constructed based on the classic crowd sensing architecture. Subsequently, fully homomorphic encryption technology is employed for plaintext-free data transmission. The encryption scheme is developed on the MFHE architecture, with additional improvements introduced through indistinguishability obfuscation and puncturable pseudorandom function methods, which serve to shorten the ciphertext and reduce complexity, rendering it more suitable for crowd sensing environments. Finally, experiments conducted on real-world datasets demonstrate that the proposed method is effective in terms of both privacy protection and time efficiency.
