The invention provides a verifying method for network
file transmission. File block transmission data and block hash codes are adopted in the method. The method comprises the following steps of: after block transmission finishes, extracting the block hash codes and comparing the extracted block hash codes with the value acquired by transmission, if an error happens, retransmitting the value from another
data source, otherwise, preserving the block data and the block hash codes in a file; after the file is transmitted, acquiring secondary
verification hash codes of file blocks from a
server, performing secondary
verification hash code extraction on the file preserving the block hash codes, comparing, if different, newly requesting the
server for the addresses of other file servers, and retransmitting; and repeating the processes till the secondary
verification hash codes of the file blocks are compared successfully. Compared with the prior art, the method has the advantages that: besides hash code verification of the file blocks, secondary verification of the hash codes of the file blocks is performed, so that the complete accuracy of
file verification is ensured and the reliability of
file transmission is improved. The secondary verified hash codes of the file blocks are acquired by secondary hash calculation of the hash codes of the file blocks, the number of the file blocks is limited, and the
advantage is obvious compared with massive time consumption in hash calculation of the whole file. When the secondary verified hash codes of the file blocks are different, error file blocks of the file can be quickly found by using the block hash codes; and compared with a mode of directly downloading the file blocks, massive
broadband resources are saved.