88.II1 gK.11.1 11?;.11.2 12Shannonn .21.3 13|.2 1.4 14Hash.31.5 15RSA?N .31?Y .42.1 11?;.42.2 12Shannonn .42.3 13|.4 2.4 14Hash.42.5 15RSA?N .4II1gKgz?S“Ik*?J?K8“1.111?;1.1XJ?Anr?OE,?1.2y“Nk=?a.1.3 ?2XJagnfcpo1.4U?1.12n11.2h?q6S?|“1.3cipher 1.4JJ“u“1.5)? x123456(x)321465cryptography“1.6000011.70001001110101111.15“ 1.8d3,4(y) = 31(y 4) mod 26 = 9(y 4) mod 26 = 9y 10 mod 261.9“?3?OA5“1.10this1.11b?k!m?N?S?5 6u?“2.212Shannonn2.313|2.414Hash2.515RSA?N4