A CRICTICAL EXAMINATION OF STREAM CIPHERS CRYPTANALYSIS

ABSTRACT

It is essential for a stream cipher to prevent a direct link from existing between the cipher’s feed (the secret key) and its outputs (the keystream), since this would compromise the security of the cryptography. Because of difficulty of a stream cipher is proportional to the amount of its inner state, the keystream that is created will inevitably begin to repeat itself at some point. It is important to note that this is not a characteristic of a typical one-time pad (OTP). When the keystream is completely random and is created individually for each letter that is sent, absolute secrecy may be provided by pure one-time pad encrypting. This is because the keystream cannot be predicted. In a situation like this one, the keystream need to be a single bit string that is made up of bits that are chosen at random and dispersed evenly throughout.  

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