Permutation control information generator for access- or communication-relative encrypting and decrypting data, has register repeating shifting, removal and shortening processes upto last permutation control information removal

摘要

The generator (2) has a length-variable n-bit circulating register, where permutation control information data with an exceeding random clock shift number uniquely occurred in the register is shifted. Permutation control information is removed after the shifting process. A ring length is shortened around a shift distance after the removing process. The remaining permutation control information data with a new exceeding random clock shift number is newly shifted. The register repeats the shifting, the removal and the shortening processes upto the last permutation control information removal.