Data Security using Hybrid Cryptography

Cryptanalyst are expert in how to break the encryption techniques. We need to safe our programs and documents from cryptanalyst. Security of information means protecting data from unauthorized access in cloud environment. There are many techniques to achieve the security of information from unauthorized access. There are two cryptographic techniques used for data encryption which are Symmetric and Asymmetric techniques. There are some advantages and disadvantages of these block cipher algorithms. Rijndael had a potentially lower security margin and better performance than being arguably simpler than many encryption techniques. Symmetric key encryption algorithms are computationally fast compared to asymmetric encryption algorithms (like RSA). However, since the same secret key is used for symmetric encryption and decryption, we have the difficult problem of securely distributing that secret key. Conversely, asymmetric key infrastructure in PKI does not rely on distribution of any private key. However, the common asymmetric algorithms are too slow to be used for bulk encryption with current computation capability. While SHA is better collision resistant to various block cipher algorithms. Thus for better security performance, we propose a system which would incorporate the advantages of these algorithms namely SHA, AES-RIJNDAEL and RSA which will be a hybrid approach of encrypting data. SHA is adopted in this mechanism to verify the integrity of the message. Three major security principles such as authentication, confidentiality and integrity are achieved together using this scheme.