1. A data transmission method, comprising:in a source apparatus, dividing original data into a plurality of source segments, performing a similarity calculation for each of the source segments to obtain a similarity set, and transmitting the similarity set to a target apparatus, wherein the similarity set comprises a similarity value of each of the source segments;
in the target apparatus, determining whether a target segment corresponding to any one of the source segments exists in the target apparatus according to the similarity set to obtain a comparison result, and transmitting the comparison result to the source apparatus;
in the source apparatus, after dehydrating the original data according to the comparison result to obtain dehydration data, transmitting the dehydration data to the target apparatus; and
in the target apparatus, rehydrating the dehydration data to the original data,
the step of dehydrating the original data according to the comparison result comprises:
applying a delta compression algorithm for each of the source segments not having the corresponding target segment in the target apparatus according to the comparison result;
applying a deduplication algorithm for a plurality of source blocks included in each of the source segments where the delta compression algorithm is not applied; and
compressing the data where the delta compression algorithm and the deduplication algorithm are not applied, so as to obtain the dehydration data.