Construction of Nonlinear Cryptographic Protocol based on Multiple Linear Cryptosystems

The paper describes the construction of nonlinear cryptographic protocol, based on separate linear cryptosystems. Implementation of suggested construction scheme enables encryption of data blocks with ready-made and proven cryptosystems, without making any changes to their design. The scheme of proposed protocol is presented, using the AES and Twofish cryptosystems as an example. The sequence of using cryptosystems proceeds based on pseudo-random cryptographically strong gamma deployment algorithm, which increases the nonlinearity of encryption and improves the general strong of systems. The article highlights the construction of nonlinear cryptosystems, model of the process of the nonlinear modifiers deployment, and proposes a general scheme of the structure of nonlinear cryptographic protocols using one or more different cryptosystems. Proposed scheme has great flexibility and scalability. This solution allows simple and effective improvement of existing cryptographic systems or their separate algorithms and is promising for further research.