Search

The increasing demand for real-time data transmission in wireless mobile communication networks has promoted the maturity of mobile communication technology. Fifth-generation (5G) mobile communication technology is combined with cloud computing, high-frequency signal transmission, and other technologies and perfectly fits with the client-server architecture. 5G has been applied in many fields, such as the interconnection of smart devices, virtual reality, and cloud-based life. To provide the security and availability of the required services, we proposed a key management scheme based on the multiserver architecture of the client-server mode in 5G networks, which uses bilinear pairings and elliptic curve cryptography. Through informal security analysis and formal analysis (under the random oracle model and ProVerif tool), we demonstrated that the proposed scheme can complete mutual authentication and resist common network attacks. Furthermore, after the performance analysis of our scheme and other related schemes, it was found that this scheme has relatively low communication and computation costs and better security performance. [ABSTRACT FROM AUTHOR]

We propose a two-dimensional modified min-sum algorithm for the LDPC codes in the fifth generation (5G) networks standard to approach the error performance of the sum-product algorithm (SPA). In the proposed decoding algorithm, we adopt a partial self-correction method followed by message amplification to improve the reliability of the variable-to-check (V2C) messages. To further approach the performance of the maximum likelihood decoding for 5G short LDPC codes, we propose an enhanced quasi-maximum likelihood (EQML) decoding method. The proposed decoding method performs multiple rounds of decoding tests once the first decoding attempt fails, where the decoder inputs of the selected unreliable variable nodes are modified in each decoding test. A novel node selection method based on the sign fluctuation of V2C messages is proposed for the EQML decoding method. We also present a partial pruning stopping (PPS) rule to reduce the decoding complexity by deactivating part of the decoding tests once a valid codeword is found. A lower bound on the error performance is also derived by using the semi-analytical method. Simulation results show that the EQML decoding method outperforms the SPA with the same decoding complexity and other QML decoding methods, and it approaches the Polyanskiy-Poor-Verdú bound within 0.4 dB. [ABSTRACT FROM AUTHOR]