Methodology for designing cryptographic systems with advanced functionality based on a modular approach

−92− Synthesiology English edition Vol.7 No.2 pp.92-104 (Sep. 2014) on average 34 pages long of which on average 24 pages were devoted to security definitions and security proofs. The contents are lists of difficult-to-understand mathematical formulas, and it is not easy to understand the correlation between these formulas and actual security. This is thought to be the major barrier in introducing highly functional cryptographic schemes to the real world. Particularly, even specialized researchers find it difficult to be convinced of the security, and a general user cannot be expected to use these schemes with full confidence. In fact, error in proof is often discovered later, even with cryptographic schemes that the designers have claimed that their security has been mathematically proven. Hereinafter, this problem will be called the security verification problem in cryptographic schemes.