dimensions of cryptography

With the use of Symmetric encryption, the principle security problem is maintaining the secrecy of the key..

Cryptology is the combination of Cryptography and Cryptanalys

There are 3 dimensions for cryptography:

1. Type of operation used for transforming plaintext to ciphertext.

In this there are two methods:

• Substitution - which means each element in the plain text is mapped into another element.
• Transposition - which means each element in the plain text is rearranged.

Most of the systems, which are also referred as product systems, involve multiple stages of substitution and transpositions.


2. Number of keys used.

if the same key is used by the sender and the receiver then it is called symmetric/single-key/secret-key/conventional encryption.


3. The way in which the plaintext is processed.

i.e. whether the data is processed in form of blocks (block cipher) or continuously (stream cipher)