Abstract

This paper is concerned with the security level expected by the canonical form of the self-synchronizing stream cipher (SSSC). A SSSC can be viewed as the combination of a shift register together with a filtering function. The maximum security of such a cipher is reached when the filtering function is random. However, in practice, pseudo random functions are used as filtering functions. In this case, we show that the security against chosen ciphertext attacks (IND-CCA security) cannot be reached but it is however secure against chosen plaintext attacks (IND-CPA secure). To relax the condition of pseudo randomness, a new family of functions with a weaker property is introduced. A connection with the left-or-right indistinguishability is made. This property provides a necessary and sufficient condition to characterize the indistinguishablity of SSSC.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.