# COMPUTER NETWORKING

## NETWORK SECURITY

### CONFIDENTIALITY

 Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
The DES algorithm has a key length of
 A 128 Bits B 32 Bits C 64 Bits D 16 Bits
Explanation:

Detailed explanation-1: -DES is a block cipher that operates on data blocks of 64 bits in size. DES uses a 64-bit key 8 × 8 including 1 bit for parity, so the actual key is 56 bits. DES, in common with other block ciphers, is based around a structure called a Feistel Lattice so it is useful to describe how this works.

Detailed explanation-2: -The DES keys are 64-bit, 128-bit, and 192-bit keys that use the DES algorithm to perform the cryptographic function. A 64-bit key is referred to as a single-length key. A 128-bit key is referred to as a double-length key.

Detailed explanation-3: -The block size in DES is 64 bits. The cipher key size is 56 bits.

Detailed explanation-4: -DES uses a 64-bit key, but because eight of those bits are used for parity checks, the effective key length is only 56 bits. The encryption algorithm generates 16 different 48-bit subkeys, one for each of the 16 encryption rounds.

There is 1 question to complete.