Unit-2 Encryption
Plaintext and ciphertext
The original data being
sent
is
known
as
plaintext. Once it has
gone
through
the
encryption algorithm, it
produce ciphertext.
Symmetric encryption
Symmetric
encryption
uses
an
encryption key; the same key is
used to encrypt and decrypt the
encoded message but it is less
secure.
It also requires a safe method to
transfer from one party to another.
Communicating parties must have
the same key in order to achieve
secure communication.
Asymmetric encryption
Asymmetric encryption was developed to overcome the security problems
associated with symmetric encryption. It makes use of two keys called the
public key and the private key:
public key (made available to everybody)
private key (only known to the computer user).
Both types of key are needed to encrypt and decrypt messages.