(b) (8 points) Consider the following proposed authentication protocol between Alice and Bob based on asymmetric encryption which is supposed to establish a shared session key K between the two users. Alice's public key is KA and Bob's public key is KB. Alice + Bob : {Alice, NAHKB Bob Alice : {K, NAHKA Alice + Bob : {Hello Bob! This is Alice, NAHK Show an attack against this protocol by demonstrating a scenario where Eve can impersonate Alice to Bob (i.e. Bob will think they are talking to Alice when they are in fact talking to Eve). Then provide a fix to the protocol to prevent this attack