Score:1

What does a deterministic MAC actually mean?

jp flag

Does a MAC that's deterministic mean it uses a PRF? Thanks for the help!

kelalaka avatar
in flag
Welcome to Cryptography,SE. Where did you see that? What is the origin of this question? A hint, see probabilistic encryption.
ness64 avatar
jp flag
@kelalaka I saw this in the Katz-Lindell textbook, question 4.8. It asks for a MAC construction that is deterministic, but doesn't rely on a PRF. I am just also wondering how one would prove that the deterministic MAC without a PRF is secure via reduction.
ness64 avatar
jp flag
Not sure, we haven't really covered those in class.
kelalaka avatar
in flag
You will see in section 4.5 GMAC and Poly1305
fgrieu avatar
ng flag
A deterministic MAC is one such that for a given key and message, the authenticator output by the MAC is always the same. That the case if the MAC is implemented by a deterministic algorithm and without an explicit random input.
mangohost

Post an answer

Most people don’t grasp that asking a lot of questions unlocks learning and improves interpersonal bonding. In Alison’s studies, for example, though people could accurately recall how many questions had been asked in their conversations, they didn’t intuit the link between questions and liking. Across four studies, in which participants were engaged in conversations themselves or read transcripts of others’ conversations, people tended not to realize that question asking would influence—or had influenced—the level of amity between the conversationalists.