A digital signature or a MAC can be used to provide a cryptographic integrity check. a. Suppose that Alice and Bob want to use a cryptographic integrity check. Which would you recommend that they use,...

A digital signature or a MAC can be used to provide a cryptographic integrity check.

a. Suppose that Alice and Bob want to use a cryptographic integrity check. Which would you recommend that they use, a MAC or a digital signature? Why?

b. Suppose that Alice and Bob require a cryptographic integrity check and they also require non-repudiation. Which would you recommend that Alice and Bob use, a MAC or a digital signature? Why?