Message authentication is a mechanism or service used to verify the integrity of a message.

• T

• F

The order in which the frame check sequence and encryption functions are performed is not critical for authentication.

• F

• T

A recipient in possession of the secret key cannot generate an authentication code to verify the integrity of the message.

• F

• T

One means of forming a MAC is to combine a cryptographic hash function in some fashion with a secret key.

• T

• F

A brute-force attack on a MAC is easier than a brute-force attack on a hash function.

• F

• T

Message authentication may also verify sequencing and timeliness.

• T

• F

The security of any MAC function based on an embedded hash function depends in some way on the cryptographic strength of the underlying hash function.

• T

• F

The straightforward use of public-key encryption provides confidentiality and authentication.

• F

• T

An important characteristic of the MAC algorithm is that it needs to be reversible.

• F

• T

As with encryption algorithms and hash functions cryptanalytic attacks on MAC algorithms seek to exploit some property of the

algorithm to perform some attack other than an exhaustive search.

• T

• F