... guarantee that this message was intended for him. Although it looks like it does (it uses Kb), it does not. Abadi realized that step 3, Bob can masquerade as Alice, and use this to fool ... certain you only use this format of the message only once between Alice, Bob, and Trent!–That is, make certain this message cannot be reused later in the protocol, or in another protocol!–It ... corresponds to. Then, Bob will be able to tell that message 5’ does not correspond to Eve’s nonce!One problem is that Trent does not know what host that Alice is trying to log onto. Eve might...