Secure two-party comparison method based on secret sharing and casual transmission

The invention discloses a secure two-party comparison method based on secret sharing and casual transmission, and belongs to the technical field of secure multi-party computing. The method comprises the following steps: generating auxiliary elements by using an OT protocol, splitting input data into a plurality of sub-blocks according to set parameters, comparing the size relationship of each sub-block by a participant by using an oblivious transmission protocol, and outputting a secret sharing result; and finally, recursively calling an N-path merging method to merge each sub-block until the size relationship of the input data of the two participating parties is obtained. According to the method, secure multi-party computing technologies such as secret sharing and casual transmission are used, so that secure and accurate comparison can be carried out on the premise of not leaking data privacy of participants; according to the method, generation of part of auxiliary elements is transferred to an offline stage