A new family of rank codes and applications to cryptography

We present a new family of so called reducible rank codes. For lengths n that are multiples of N the family contains optimal codes over F/sub N/. A public key cryptosystem using these codes is proposed. To make the system resistant to structural attacks, row and column scramblers are used, as well as a special form of distortion matrix. A preliminary analysis shows that the system is secure against known attacks for keys greater than 20 Kbits.