Cryptography




Symmetric Key EncryptionAsymmetric Key Encryption
It only requires a single key for both encryption and decryption.It requires two key one to encrypt and the other one to decrypt.
The size of cipher text is same or smaller than the original plain text.The size of cipher text is same or larger than the original plain text.
The encryption process is very fast.The encryption process is slow.
It is used when a large amount of data is required to transfer.It is used to transfer small amount of data.
It only provides confidentiality.It provides confidentiality, authenticity and non-repudiation.
Examples: 3DES, AES, DES and RC4Examples: Diffie-Hellman, ECC, El Gamal, DSA and RSA
In symmetric key encryption, resource utilization is low as compared to asymmetric key encryption.In asymmetric key encryption, resource utilization is high.

 


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