2019 | vol. 67 | nr. 2 | art. 9

A Cryptosystem Architecture and Design for Encrypted Data Transmissions

Mohammed Zakarya BABA-AHMED, Fatima Zohra BENMANSOUR, Amina SEDJELMACI
Data encryption has become obvious to prevent all types of malicious attacks, the security of information circulating in networks are necessary. If a few years ago the need for security was restricted to military and governmental circles, today security is essential at all levels of communication in a modern society. Bank transactions have the obvious need to be secure, but also the transfer of information from a digital TV channel to a set-top box at its customer must preserve the integrity and confidentiality of data against malicious attacks. To prevent these attacks, the notion of security must be omnipresent. Both when the data travels over the networks and they are not used. Hence the need to encrypt the data. Cryptography is represented by the study of the methods allowing the sending of the data in a confidential way on a given support. It is characterized by two categories: secret key cryptography and public key cryptography. Public key algorithms such as RSA (RIVEST, SHAMIR and ADELMAN), which require the use of very large keys (1024 bit and more) for an acceptable level of security are unable to encrypt a huge amount of data in an environment in real time Therefore, public key encryption algorithms are mainly used in exchange protocols and when non-repudiation is required. Therefore, this data can be processed only by secret key cryptographic algorithms such as AES (Advanced Encryption Standard), but like any technology with its flaws [4], the symmetric ones suffer from the problem of the security of the exchange of keys that requires a very secure transmission channel unfortunately not available. In this article, we wanted to make a hybrid crypto-system design benefiting from the processing speed of a symmetric algorithm and the enhanced security of the asymmetric algorithm, a new architecture will be proposed to describe the symmetric system as well as the hybrid system to explain steps of the symmetric AES algorithm by optimizing the fourth step of symmetric encryption which is the mix columns in order to separating the scrambling matrix for encryption and decryption into several matrices to avoid multiplication in binary that will change the programming results in VHDL (VHSIC Hardware Description Language) to make a hardware description of this architecture as well as the simulation by ModelSim to check the results obtained. Field Programmable Gate Arrays (FPGAs) enable the best use of hardware resources and meet real-time application constraints to achieve good security performance.
Keywords: cryptography, secret key, public key, security, architecture
To cite this article: BABA-AHMED M.Z., BENMANSOUR F.Z., SEDJELMACI A., “A Cryptosystem Architecture and Design for Encrypted Data Transmissions”, in Electrotehnica, Electronica, Automatica (EEA), 2019, vol. 67, no. 2, pp. 76-83, ISSN 1582-5175.