a. We first try to understand the p

a. We first try to understand the protocol designer’s reasoning:
—Why would A and B believe after the protocol ran that they share with the other party? —Why would they believe that this shared key is fresh?
In both cases, you should explain both the reasons of both A and B, so your answer should complete the sentences
A believes that she shares with B since...
B believes that he shares with A since...
A believes that is fresh since...
B believes that is fresh since...
b. Assume now that A starts a run of this protocol with B.However,the connection is intercepted by the adversary C.Show how C can start a new run of the protocol using reflection,causing A to believe that she has agreed on a fresh key with B (in spite of the fact that she has only been communicating with C).Thus,in particular, the belief in (a) is false. c. Propose a modification of the protocol that prevents this attack. 14.7 What are the core components of a PKI? Briefly describe each component. 14.8 Explain the problems with key management and how it affects symmetric cryptography.