µÚ¶þÕ£º¶Ô³ÆÃÜÂëѧ
±í2.3 ÿÂÖÒÆ¶¯µÄλÊý
ÂÖ1 2 3 4 5 6 7 8 9 11111110 1 2 3 4 5 6 ´Î λ1 1 2 2 2 2 2 2 1 2 2 2 2 2 2 1 Êý ÒÆ¶¯ºó£¬½«Á½²¿·ÖºÏ²¢³É56λºóͨ¹ýѹËõÖû»PC-2ºóµÃµ½48λ×ÓÃÜÔ¿¡£¼´£º
Ki=PC-2(CiDi)¡£Ñ¹ËõÖû»Èç±í2.4£º
±í2.4 ѹËõÖû»PC-2 11121 5 3 24 7 1 4 8 16 212114 5 1 0 3 9 2 28 17 2212 6 6 7 0 3 453345341 2 1 7 7 5 0 0 543444351 5 3 8 4 9 9 6 354453234 3 6 2 0 6 9 2
×ÛÉÏËùÊö£¬Õû¸ö×ÓÃÜÔ¿»ñµÃ¹ý³ÌÈçͼ2-14£º
43
µÚ¶þÕ£º¶Ô³ÆÃÜÂëѧ
64λÃÜÔ¿ PC-1 <<< <<< PC-2 <<< <<< ×ÓÃÜÔ¿K1 PC-2 ×ÓÃÜÔ¿K2 <<< <<< PC-2 <<< <<< ×ÓÃÜÔ¿K15 PC-2 ×ÓÃÜÔ¿K16 ͼ2-14×ÓÃÜÔ¿²úÉú
? ÃÜÂ뺯Êýf
ÃÜÂ뺯ÊýfµÄÊäÈëÊÇ32±ÈÌØÊý¾ÝºÍ48±ÈÌØµÄ×ÓÃÜÔ¿£¬Æä²Ù×÷²½ÖèÈçͼ2-15£º
44
µÚ¶þÕ£º¶Ô³ÆÃÜÂëѧ
ͼ2-15 f(Ri,Ki)¼ÆËã
1¡¢À©Õ¹Öû»£¨E£©
½«Êý¾ÝµÄÓҰ벿·ÖRi´Ó32λÀ©Õ¹Îª48λ¡£Î»Ñ¡Ôñº¯Êý£¨Ò²³ÆE-ºÐ£©Èç±í2.5£º
±í2.5 À©Õ¹Öû»E 31 2 3 4 5 2 4 5 6 7 8 9 8 9 11110 1 2 3 1111112 3 4 5 6 7 2222220 1 2 3 4 5 223331 8 9 0 1 2 2¡¢Òì»ò
À©Õ¹ºóµÄ48λÊä³öE(Ri)ÓëѹËõºóµÄ48λ×ÓÃÜÔ¿Ki×÷Òì»òÔËËã¡£
45
µÚ¶þÕ£º¶Ô³ÆÃÜÂëѧ
3¡¢SºÐÌæ´ú
½«µÚ¶þ²½Òì»òµÃµ½µÄ48λ½á¹û·Ö³É8¸ö6λµÄ¿é£¬Ã¿Ò»¿éͨ¹ý¶ÔÓ¦Ò»¸öSºÐ²úÉúÒ»¸ö4λµÄÊä³ö¡£8¸öSºÐÈç±í2.6£¬×¢Òâ±íÖи÷Ïî²ÉÓõÄÊ®Áù½øÖƱíʾ£º
±í2.6 DES SºÐ
S0 1 2 3 4 5 6 7 8 9 A B C D E F 1 0 E 4 D 1 2 F B 8 3 A 6 C 5 9 0 7 1 0 F 7 4 E 2 D 1 A 6 C B 9 5 3 8 2 4 1 E 8 D 6 2 B F C 9 7 3 A 5 0 3 F C 8 2 4 9 1 7 5 B 3 E A 0 6 D S0 1 2 3 4 5 6 7 8 9 A B C D E F 2 0 F 1 8 E 6 B 3 4 9 7 2 D C 0 5 A 1 3 D 4 7 F 2 8 E C 0 1 A 6 9 B 5 2 0 E 7 B A 4 D 1 5 8 C 6 9 3 2 F 3 D 8 A 1 3 F 4 2 B 6 7 C 0 5 E 9 S0 1 2 3 4 5 6 7 8 9 A B C D E F 3 0 A 0 9 E 6 3 F 5 1 D C 7 B 4 2 8 1 D 7 0 9 3 4 6 A 2 8 5 E C B F 1 2 D 6 4 9 8 F 3 0 B 1 2 C 5 A E 7 3 1 A D 0 6 9 8 7 4 F E 3 B 5 2 C S0 1 2 3 4 5 6 7 8 9 A B C D E F 4 0 7 D E 3 0 6 9 A 1 2 8 5 B C 4 F 1 D 8 B 5 6 F 0 3 4 7 2 C 1 A E 9 2 A 6 9 0 C B 7 D F 1 3 E 5 2 8 4 3 3 F 0 6 A 1 D 8 9 4 5 B C 7 2 E S0 1 2 3 4 5 6 7 8 9 A B C D E F 5 0 2 C 4 1 7 A B 6 8 5 3 F D 0 E 9 46