Symmetric key encryption is also known as shared-key, single-key, secret-key, and private-key or one-key encryption. In this type of message encryption, both sender and receiver share the same key which is used to both encrypt and decrypt messages. Sender and receiver only have to specify the shared key in the beginning and then they can begin to encrypt and decrypt messages between them using that key. Examples include AES (Advanced Encryption Standard) and TripleDES (Data Encryption Standard).
- Simple: This type of encryption is easy to carry out. All users have to do is specify and share the secret key and then begin to encrypt and decrypt messages.
- Encrypt and decrypt ...view middle of the document...
The private key is kept secret and is used to decrypt received messages. An example of asymmetric key encryption system is RSA.
- Convenience: It solves the problem of distributing the key for encryption.Everyone publishes their public keys and private keys are kept secret.
- Provides for message authentication: Public key encryption allows the use of digital signatures which enables the recipient of a message to verify that the message is truly from a particular sender.
- Detection of tampering: The use of digital signatures in public key encryption allows the receiver to detect if the message was altered in transit. A digitally signed message cannot be modified without invalidating the signature.
- Public keys should/must be authenticated: No one can be absolutely sure that a public key belongs to the person it specifies and so everyone must verify that their public keys belong to them.
- Slow: Public key encryption is slow compared to symmetric encryption. Not feasible for use in decrypting bulk messages.
- Uses up more computer resources: It requires a lot more computer supplies compared to single-key encryption.