الفهرس يوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
In the last few years, the merging of computer and communication technologies has been developing progressively. The need of security to protect the data through networks has become of vital importance. This area of research has become quite active in the recent years. There are two types of cryptographic systems, used in network security, symmetric and Asymmetric cipher system.
In This thesis, a new symmetric block cipher algorithm has been designed, named, a Robust Blowfish Block Cipher (RBBC), which represents an improvement of the Blowfish Algorithm (BFA). The main drawback of the BFA is in its key generation algorithm, it is only suitable for applications where the key does not change often. The proposed RBBC is designed to overcome this problem, and meets the Advanced Encryption Standard (AES) requirements. Software / Hardware design techniques were presented for the proposed RBBC, to improve the performance of secret key cipher algorithm, and the hardware implemented for the BFA.
To realize the proposed RBBC, and the BFA in hardware a Field Programmable Gate Arrays (FPGAs) are chosen as a target hardware environment, by using a very high speed integrated circuit hardware description language (VHDL) code. Simulating the code on ”ModeJsim SE plus 5.8b”, Synthesizing, and implementing. The code on ”Xilinx- project Navigator, ISE 6.3” with device SPARTAN- 3 families XC3S200 FT 256. the results are compared with the famous block cipher algorithms.