Exam 12: Message Authentication Codes

Message encryption by itself cannot provide a measure of authentication.

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

The approach taken by the Transport Layer Security protocol and the Wireless Transport Layer Security Protocol involve invoking HMAC _________ for each block of output wi.

Attacks on MACs can be grouped into two categories: brute-force attacks and __________ .

HMAC is a widely used standardized _________ function and is implemented in many protocols and applications.

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

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

Discovery of the pattern of traffic between parties is a __________ attack.

The __________ mode of operation is designed to be parallelizable so that it can provide high throughput with low cost and low latency.

The MAC function is a __________ function.

Two MACs that are based on the use of a block cipher mode of operation are Data Authentication Algorithm and __________ .

The essential elements of any pseudorandom number generator are a __________ and a deterministic algorithm for generating a stream of pseudorandom bits.

A __________ is an algorithm that requires the use of a secret key.

Any modification to a sequence of messages between parties,including insertion,deletion,and reordering is a __________ attack.

__________ assures that data received are exactly as sent and that the purposed identity of the sender is valid.

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.

Confidentiality can be provided by performing message encryption __________ the MAC algorithm.

An alternative authentication technique involves the use of a secret key to generate a small fixed size block of data known as a __________ or MAC that is appended to the message.

The _________ attack is when the attacker is looking for two messages M and M1 that produce the same hash: HM)= HM1)

NIST SP 800-90,IEEE 802.11i,and TLS/WTLS are three ____________ based on HMAC.