1 What is a message authentication code? 2 What is the difference between a message authentication code and a one-way hash function? 3 In what ways can a hash value be secured so as to provide message...

1
What is a message authentication code?

2
What is the difference between a message authentication code and a one-way hash function?

3
In what ways can a hash value be secured so as to provide message authentication?

4
Is it necessary to recover the secret key in order to attack a MAC algorithm?

5
What changes in HMAC are required in order to replace one underlying hash function with another?