# A CP-ABE Scheme Based on Lattice LWE and Its Security Analysis
## 3 Our Ciphertext-Policy ABE Scheme for NC\({}^{1}\) Circuits Based on LWE
### Security Analysis
We prove the correctness of the scheme and give strict proof of security. At the same time, we also give a comparison of the computational cost between this scheme and the one in [20], and, in order to better understand the scheme, we recommend several groups of parameters through a series of strict calculations. Finally, we give a simple example to demonstrate the overall operation process of the algorithm. This scheme may provide some ideas for constructing other CP-ABE and multi-authority attribute encryption schemes, and the two-stage sampling algorithm involved in this scheme may be used in other cryptographic schemes to optimize the existing performance. Conceptualization, Y.Y. and L.S. ; methodology, Y.Y. ; validation, Y.Y., L.S., Q.W. and K.W. ; security analysis, H.C. and L.S. ; investigation, Y.Y., Q.W. and K.W. ; writing--original draft preparation, Y.Y. ; writing--review and editing, Y.Y. and H.C.; visualization, K.W. ; supervision, K.W. ; data curation Q.W. ; project administration, H.C.; funding acquisition, H.C. All authors have read and agreed to the published version of the manuscript. This research was funded by the First-class Discipline Construction Project of Beijing Electronic Science and Technology Institute (No: 3201017) and the National Natural Science Foundation of China (No: 61772047). The APC was funded by the First-class Discipline Construction Project of Beijing Electronic Science and Technology Institute (No: 3201017) and the National Natural Science Foundation of China (No: 61772047). Not applicable. The authors declare no conflict of interest. ## References

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