PN序列产生-讲义

PN序列产生-讲义Guang Gong Dept. Electrical and Computer Engineering

Design of Pseudo-random Sequence Generators (Cont.)
Lecture 2: n Design of PRSGs Towards Large Linear Span n Applications in Stream Cipher Design: A5 and w7

Lecture 2

@ G. Gong

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3. Design of PRSGs Towards Large Linear Span
One-time-pad and Design Principles of Stream Ciphers Known Approaches for Design of PRSG Based on LFSR

Lecture 2

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Cryptanalyst

^ c ^ k

Message source

m

Encrypter

c

Decrypter

Destination

k

Secure channel

Key generator

Model of Conventional Cryptosystem
Lecture 2 @ G. Gong 3

Model of Stream Cipher

Message source

m = m1, m2, ...

Cipher
c = c1 , c2, ... + k = k1, k2, ...

Key generation

K, seed

Lecture 2

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One-time-pad
One-time-pad means that different messages are e