please i want full clear solution DONOT COPY

15 points) User Authentication. (7 points) Consider the following proposed authentication protocol between Alice and Bob based on symmetric encryption with a trusted third party (TTP) which is supposed to establish a shared session key K between the two users. AliceTTP:Alice,BobTTPAlice:{K}KAT,{K}KBTAliceBob:{K}KBTBobAlice:{HelloAlice!ThisisBob}K Show an attack against this protocol by demonstrating a scenario where Eve can impersonate Bob to Alice (i.e. Alice will think they are talking to Bob when they are in fact talking to Eve). Then provide a fix to the protocol to prevent this attack