三重DES增加了密钥长度，由56位增加到112或168位，有更高的安全性，而且在新一代因特网安全标准IPSEC协议集中已将DES作为加密标准。-3DES key length increased from 56 to 112 or 168. have higher security, and the new generation of Internet security standards IPSEC agreement has bee