Cryptcoding - Encryption and Error-Correction Coding in a Single Step

In this paper we re-open a 25 years old question of joint encryption and error-correction coding, named here as Cryptcoding. Cryptcoding is a procedure in which encryption/decryption and error-correction coding/decoding are performed in a single step. We discuss the advantages of this approach over the traditional First-Encrypt-Then-Encode approach. To our knowledge only three different realizations of cryptcoding can be found in litterature: the McEliece's public key encryption system using Goppa codes, the Kak's joint encryption and error-correction coding using D-sequences and the recently developed quasigroup random error-correcting codes. We briefly discuss the first two and mainly focus on the last one. We give two examples in which cryptcoding is efficiently employed for secure document management.