使用3DES和MD5算法对文件进行加密和md5值的计算，用于加密文件的传输。使用标准的3DES和MD5算法作为基础，提供了标准的接口。-use 3DES and MD5 algorithm to encrypt documents and md5 value calculation, for the transmission of encrypted files. Three criteria for the use of DES and MD5 algorithm as a basis for providing a standard interface.