Private-key encryption based on concatenation of codes

Public-key algebraic encryption (PUAE) has certain advantages that make it attractive in some applications. Variants of PUAE for private-key algebraic encryption (PRAE); have been proposed subsequently. PRAE is proven to be insecure under chosen plaintext attack. In the paper, some invariants of PRAE are studied, and a private-key cryptosystem based on concatenation of codes is proposed and analysed. The new system is, composed of short-length codes and is designed to avoid the weaknesses in other PRAE systems. The system looks secure against known attacks. Some methods to improve the system information rate and security are also suggested