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

In recent years,
Coded Edge Computing
(CEC) has been greatly studied as a promising technology to effectively mitigate the impact of stragglers and provide confidentiality in edge collaborative computing. It is crucial to verify the correctness of both intermediate results and the final result especially in untrustable and unreliable edge computing scenarios. However, the existing works on verification in CEC always verify and directly discard the whole incorrect intermediate results. In this paper, we propose the
Partial Decode and Compare
(PDC) verification scheme, which can fully utilize the correct part in the incorrect intermediate results to reduce the complexity and tolerate more abnormal edge devices. The PDC verification scheme consists of two parts:
Final Result Verification
(FRV) and
Abnormal Edge Device Identification
(AEDI). By deeply analyzing the decoding impact of the intermediate results on the final result, the PDC verification scheme divides the intermediate results and final results into
subresult vectors
. It decodes, compares, and verifies the final result in units of subresult vectors. In this way, the obtained parts which verified to be correct do not need to participate in the following verification. Therefore, it can significantly reduce the verification overhead including both the number of required decoding rounds and the complexity of each decoding round. Based on the correct final result verified by the PDC verification scheme, we also propose an
Abnormal Edge Devices Identification
scheme to identify all abnormal edge devices that return incorrect intermediate results. We then present extensive theoretical analyses and simulation experiments of the PDC verification scheme, which demonstrates that the PDC verification scheme can tolerate a higher ratio of incorrect intermediate results and achieve lower verification overhead than the state-of-the-art verification works. Therefore, the proposed PDC verification scheme enables CEC to provide reliable services in unstable and unreliable edge computing scenarios.