Abstract
A Shannon cipher system for memoryless sources in which distortion is allowed at the legitimate decoder is considered. The source is compressed using a secured rate distortion code, which satisfies a constraint on the compression rate, as well as a constraint on the exponential rate of the excess-distortion probability at the legitimate decoder. Secrecy is measured by the exponential rate of the exiguous-distortion probability at the eavesdropper, rather than by the traditional measure of equivocation. The perfect-secrecy exponent is defined as the maximal exiguous-distortion exponent achievable when the key rate is unlimited. The reproduction-based estimate exponent is defined as the maximal exiguous-distortion exponent achievable for a genie-aided eavesdropper, which knows the secret key. Under limited key rate, it is proved that the maximal achievable exiguous-distortion exponent is equal to the minimum between the key rate plus the reproduction-based estimate exponent, and the perfect-secrecy exponent. The result is generalized to a fairly general class of variable key-rate and coding-rate codes.
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 callDisclaimer: 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.
