As the speed of processors and knowledge about cryptanalysis goes on increasing day by day, the original encryption methods prove to be insufficient for better security. As large amount of data is transmitted over the network, it is preliminary to secure all types of data before sending it.. The problem with AES, most extensively used encryption, is that it uses many multivariate equations which are linear in nature. Thus it can be broken using algebraic cryptanalysis. This provides a serious threat as AES was considered to be unbreakable and thus it was used in many encryption systems. The paper presents the design and implementation of a hybrid based 128 bit key AES-DES algorithm as a security enhancement.

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SBox XOR Cipher Key matrix Hybrid AES DES Chaos Feistal network