北交大 密码学课件 第2章古典密码体制续密码分析2016.ppt

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1、第2章古典密码体制续——密码分析本节主要内容攻击模型仿射密码的密码分析代换密码的密码分析维吉尼亚密码的密码分析Hill密码的密码分析攻击模型攻击模型字母概率字母概率A0.082B0.015C0.028D0.043E0.127F0.022G0.020H0.061I0.070J0.002K0.008L0.040M0.024N0.067O0.075P0.019Q0.001R0.060S0.063T0.091U0.028V0.010W0.023X0.001Y0.020Z0.001仿射密码的密码分析字母频数字母频数A2B1C0D7E5F4G0H5I0J0K5

2、L2M2N1O1P2Q0R8S3T0U2V4W0X2Y1Z0代换密码的密码分析字母频数字母频数A0B1C15D13E7F11G1H4I5J11K1L0M16N9O0P1Q4R10S3T2U5V5W8X6Y10Z20维吉尼亚密码的密码分析.034.031.035.044.047.037.043.038.042.037.033.032.035.047.036.045.032.029.044.072.036.027.030.058.036.0375.045.032.033.038.060.034.034.034.050.033.033.043.040.0

3、33.028.036.040.044.037.050.034.034.039.044.038.0354.048.029.042.043.044.034.038.035.032.049.035.031.035.065.035.038.036.045.027.035.034.034.037.035.046.0403.069.044.032.035.044.034.036.033.030.031.042.045.040.045.046.042.037.032.034.037.032.034.043.032.026.0472.035.031.036.037

4、.035.039.028.028.048.061.039.032.040.038.038.044.036.030.042.043.036.033.049.043.041.0361的值i希尔密码的密码分析