A cryptography using advanced substitution technique and symmetric key generating algorithm

Cryptographic algorithm plays an important role to secure the confidential data while transmitting over the cloud. Modern cryptography offers a variety of encryption scheme for protecting the data. A key used for encrypting the plain text is another vital component on which the secrets depend. Advanced Encryption Standard (AES) algorithm is used in this research. This paper focus on developing a new way to generate the key called Chaive Unica (CU) which is used only once and a new way of substitution method called Advanced Substitution Technique (AST) which is more secure to encrypt the message. The plain text is encrypted twice before sending the message into algorithm. A new architecture is proposed in order to encrypt the text in secured way.