Differentiate between the $2$ categories of attacks.

$[2$ marks$]$

Explain how public key cryptosystems can be used for both authentication and confidentiality.

$[3$ marks$]$

Using Caesar Cipher with Key$=8,$ encrypt the plaintext CONGRATULATIONS.

$[4$ marks$]$

Explain the $3$ characteristics of cryptographic systems.

$[6$ marks$]$

Diagrammatically demonstrate the general architecture of a Network Security model.

$[4$ marks$]$

Outline $3$ differences between Data Encryption Standard and Simplified Data Encryption Standard

$[3$ marks$]$

Explain the Cipher Block Chaining encryption and decryption procedures with appropriate diagrams.

$[6$ marks$]$

How is a hoax both a threat and an attack?

$[3$ marks$]$