With explain the encryption model the help of diagram.

Symmetric cipher model uses the secret-key or a single-key for encryption/decryption purposes. It employs a symmetric encryption, also known as conventional encryption single-key or secret-key encryption.

A few symmetric key algorithms are stated below,

1. Data Encryption Standard also well known as DES

2. Triple DES also known as3DES

3. International Data Encryption Algorithm also known as IDEA

Symmetric cipher model as shown in the figure drawn below consists of five components,

Plaintext is defined as follows:

It refers to the original message which is not encrypted and is in human readable format. It forms the input to an encryption algorithm and output of or the decryption algorithm.

Example of it is

A text document is the executable file or the image.

2.   Encryption Algorithm is defined below:

Application of this algorithm will transform the plaintext to an unreadable, unintelligible form by performing many transformations and substitutions.

 3. Secret-key is defined below:

It is a cost of data which is randomly selected. It acts as an input to the encryption and decryption algorithms both. Thus, the sender and receiver both must share the same key and make sure which is secured, in order to restrict the intruders from reading the messages. The encryption algorithm does the transformations and substitutions on the plaintext consequently, depending on the key.

4. Cipher text is defined below:

It is a scrambled version of the plaintext and is not in a human-readable format. The cipher text produced by encryption algorithm depends on the secret-key and plain text. The encryption algorithm can produce different cipher text for the same plain text by using various secret-keys.

5.   Decryption Algorithm is defined below:

It is a reversed form of the encryption algorithm. It takes the cipher text (that is the encrypted data) as the input and decrypts it, using the same key which was used by the encryption algorithm in order to produce the plaintext (that is original message or data).