linear feedback shift register in cryptography

If a data is lost or extra bit gets added while transmission, the system will automatically show error as all the processes are synchronised. Index Terms - octal word time generation, linear feedback shift register, feedback function, data security, priority encoder, email server, SMTP(simple mail transfer protocol) ,POP(post office protocol), device sensitive password check.Īn efficient method to modify the plain text into an encoded cipher text, not easily predictable ensuring that the key value is irrecoverable when data is attacked while being transmitted. It can provide about 80-85% data security as decoding of data involves inverting the feedback function or generating the binary sequence which will help in retrievi ng the data after some recombination operation. Subhra Mazumdar, Tannishtha Som Abstract - A data encryption technology which ensures secrecy of the data while being transferred over a long distance. The research paper published by IJSER journal is about Data Encryption with Linear Feedback Shift Register 1ĭata Encryption with Linear Feedback Shift In these works, an evolutionary algorithm learns how to apply different operations on strings from LFSR to enhance their quality to meet the criteria of a fitness function, here the NIST protocol, effectively.Data Encryption with Linear Feedback Shift Register New methods suggest usage of evolutionary algorithms in order to introduce non-linearity. Using bruteforce methods, a list of maximum-period n-bit NLFSRs for n ≤ 25 has been made as well as for n=27. It is known how to generate an n-bit NLFSR of maximal length 2 n, generating a De Bruijn sequence, by extending a maximal-length LFSR with n stages but the construction of other large NLFSRs with guaranteed long periods remains an open problem.

NLFSRs are known to be more resistant to cryptanalytic attacks than Linear Feedback Shift Registers ( LFSRs). Nonlinear-feedback shift registers are components in modern stream ciphers, especially in RFID and smartcard applications.

Where f is the non-linear feedback function. A nonlinear-feedback shift register (NLFSR) is a shift register whose input bit is a non-linear function of its previous state.įor an n-bit shift register r its next state is defined as:

Linear feedback shift register in cryptography