Improved Multi-User Security Using the Squared-Ratio Method

ePrint Report: Improved Multi-User Security Using the Squared-Ratio Method

Yu Long Chen, Wonseok Choi, Changmin Lee

Proving security bounds in contexts with a large number of users is one of the central problems in symmetric-key cryptography today. This paper introduces a new method for information-theoretic multi-user security proofs,
called ``the Squared-Ratio Method''. At its core, the method requires the expectation of the square of the ratio of observing the so-called good transcripts (from Patarin's H-coefficient technique) in the real and …

called chen cryptography eprint report information key large lee problems report security symmetric user security