Exam 21: Public-Key Cryptography and Message Authentication

A __________ type of attack exploits properties of the RSA algorithm.

The key exchange protocol is vulnerable to a man-in-the-middle attack because it does not authenticate the participants.

The __________ uses an algorithm that is designed to provide only the digital signature function and cannot be used for encryption or key exchange.

If speed is a concern,it is fully acceptable to use _________ rather than SHA as the embedded hash function for HMAC.

The National Institute of Standards and Technology has published Federal Information Processing Standard FIPS PUB 186,known as the __________.

One of the first public-key schemes,_______,was developed in 1977 by Ron Rivest,Adi Shamir,and Len Adleman.

The Diffie-Hellman algorithm depends for its effectiveness on the difficulty of computing discrete logarithms.

_________ are analogous to a burglar guessing a safe combination by observing how long it takes to turn the dial from number to number.

The purpose of the __________ algorithm is to enable two users to exchange a secret key securely that can then be used for subsequent encryption of messages.

HMAC can be proven secure provided that the embedded hash function has some reasonable cryptographic strengths.

A hash function such as SHA-1 was not designed for use as a MAC and cannot be used directly for that purpose because it does not rely on a secret key.

In 2005,NIST announced the intention to phase out approval of _______ and move to a reliance on the other SHA versions by 2010.

_________ attacks have several approaches,all equivalent in effort to factoring the product of two primes.

SHA-1 is considered to be very secure.

___________ was the first published public-key algorithm.

The Secure Hash Algorithm (SHA)was developed by the _________ and published as a federal information processing standard (FIPS 180)in 1993.

The appeal of HMAC is that its designers have been able to prove an exact relationship between the strength of the embedded hash function and the strength of HMAC.

SHA-2 shares the same structure and mathematical operations as its predecessors and this is a cause for concern.

The _________ attack exploits the common use of a modular exponentiation algorithm in RSA encryption and decryption,but can be adapted to work with any implementation that does not run in fixed time.

"Must support hash value lengths of 224,256,384,and 512 bits" and "algorithm must process small blocks at a time instead of requiring the entire message to be buffered in memory before processing it" are requirements for ________.