DES :
(ECB Electronic Code Book). DES .
. .
(CBC Cipher Block Chaining). Ci , i>=1, 2 Mi + 1. C0 - .
, , .
(CFB Cipher Feed Back). CFB ""
Z0, Z1,..., Zi = DESk(Ci − 1) .
C0 .
(OFB Output Feed Back). OFB ""
Z0, Z1,..., , i>=1.
-
:
- ECB , .
- ECB OFB 64- Ci Mi, .
- CBC CFB i Mi, Mi +1 Mi Mi + 1, Mi + 2... .
:
.
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. , . , .