Cyber security plays a vital role in data communication in every aspect of information exchange through internet. Data has to be secured from unauthorized users and should be transmitted to the intended receiver with confidentiality and integrity. Cryptography is a technique which provides the security by encrypting and decrypting the data in a secured network. Many cryptographic algorithms are available which falls under either symmetric or Asymmetric techniques. To choose an algorithm for secure data communication ,the candidate algorithm should provide higher accuracy , security and efficiency. This paper presents the implementation limitations of existing cryptographic algorithms such as DES, TDES, AES, BLOWFISH, IDEA, RC6, CAST-128 of symmetric techniques and RSA of Asymmetric . This paper analyses parameters like Key exchange, flexibility and security issues of the algorithms which determines the efficiency of crypto system .

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Cryptography Symmetric asymmetric Architecture Security Limitations Aes Des Rsa Secure Key Management.