Student Question

A cryptographic strong hash function may be

obtained using the following method: A$.$ Using a

CBC mode of a compression function based on a

public $-$ key encryption algorithm B$.$ None of the

above C$.$ Using a simple checksum mechanisms

for error detection D$.$ Using a cryptographically

strong compression function E$.$ Using a CBC

mode of a compression function based on a strong

symmetric $-$ key encryption algorithm $2.$ In the

following list of questions fegarding

authentication, which one is the best answer? A$.$

Let $H$ be a hash function with output length $m.$

Then the square root of the $m-$ th power of $2$ is the

upper bound of the cryptographic strength of $H$

becasue of birthday attacks. B$.$ Hash functions are

used in authentication for the purpose of speeding

up calculations and reducing network traffic. C$.$

The strength of SHA$-160$ is at least the $79$th power

of D$.$ All of the above. E$.$ All of the above except

F$.$ None of the above.