There are two types of key technology:private key and public key.Private-key encryption methods are called(1)ciphers,information is encrypted with(2)both the sender and receiver hold privately.Public—key encryption methods are called(3)ciphers,(4)created for each user,encryption key and decryption key are(5).
* D0 G8 a0 w# a7 j9 ^. `& j+ M (1)A.synchronous
% i9 s" v+ t. h# g* F9 b B.asynchronous
" A3 ^: s) X& D2 F- B C.symmetric7 l; ^9 ?1 y6 a8 d- J/ w1 N' k; _5 i
D.asymmetric
$ a& p' j6 F, ` (2)A.a key
" x' A- A( ]5 g2 z, ^ B.two keys
, a7 ~( R) O4 B6 i1 n C.three keys
9 R7 ]0 O- P/ z2 Q1 q7 M5 h D.four keys - N0 Y t) _! x, q) X8 t
(3)A.synchronous
. I9 ]# |9 B5 Q3 n) p" c$ G B.asynchronous8 B( B' A9 q/ L# O5 x2 o* T
C.symmetric
. R( v1 x9 C+ }$ u* r7 ] D.asymmetric& o. Y2 e! \* B) K8 e
(4)A.two related keys are 3 q8 r' @8 ^4 Y# }8 X" z; K
B.a key is
. O7 S* o! |: o' k- j- P0 d b C.two unrelated keys are
* Y9 Y) x, q+ t' R: K D.three keys are) Z$ ^8 _/ j x: @2 ^3 N
(5)A.same9 r7 Z G, l% I, W4 Z& H
B.different 2 n0 A) k. w, v. w9 W2 T7 o6 l* w
C.difference
& s$ J) j3 s% ] D.some
- i( I' e' y5 K/ V' R- [ n+ ~ 答案:(1)C (2)A (3)D (4)A (5)B
$ S9 _* }7 r# c3 q2 a% }5 ?, j! J 解析:有两种加密技术:私有密钥和公开密钥。私有密钥加密方法被称为对称密钥加密,在发送者和接受者之间的信息共同具有同一个密钥,公开密钥加密方法被称为非对称密钥加密,对于每一个使用者,都建立两个相关的加密与解密密钥,但它们不同。 |