1: Encrypt the following message using play fair cipher. Key – “INFORMATION SECURITY” Message – “NOTHING IS SECURE” 2: Suppose you have to design a symmetric key block cipher algorithm. Give your...

1:
Encrypt the following message using play fair cipher.

Key – “INFORMATION SECURITY”

Message – “NOTHING IS SECURE”

2: Suppose you have to design a symmetric key block cipher algorithm. Give your reason how will you decide following [3]

1. Algorithm should be private or public


2. Data block size decision


3. Key size


4. Number of rounds