Decode-and-Compare: An Efficient Verification Scheme for Coded Distributed Edge Computing

Abstract

Recently, edge computing has demonstrated increasing potential to provide low-latency computing services. Coded edge computing can not only make full use of the resources of heterogeneous edge computing servers, but also significantly reduce the negative effects of slow computing devices on computing time. Nevertheless, since edge servers may be unreliable or untrustworthy, the user will decode and get incorrect computation results even if it uses one incorrect sub-computation result returned by faulty edge servers. In this paper, for the existing coded edge computing schemes, we focus on the distributed matrix-matrix multiplication and design a general and efficient <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Decode-and-Compare Verification</i> (DCV) scheme to verify the correctness of computation results and identify faulty edge servers by utilizing the properties of coded computing itself. The DCV scheme contains two components: (1) computation result verification, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i.e.</i> , obtain the computation result and verify its correctness, and (2) faulty edge server identification, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i.e.</i> , identify the faulty edge servers by verifying the correctness of returned sub-computation results. For both the independent and collusion faulty edge server models, we conduct solid theoretical analyses on the required decoding rounds, the coding redundancy and the successful verification probability to demonstrate that the correct computation result can be efficiently verified. We also conduct a lot of experiments on the DCV scheme from different aspects and the results show that it achieves much less computation time to get the correct computation result compared with other potential schemes, including homomorphic encryption and local computation.