Alice and Bob use encryption for the confidentiality of thei…

Alice and Bob use encryption for the confidentiality of their messages. However, they are concerned about their messages being tampered with by Trudy and whether it’s not Trudy they are communicating with rather than with each other. In this context answer the following questions: [5 points each] a) Can encryption alone address their confidentiality, integrity and authentication concerns? Explain your answer. b) Their network manager suggests that they use the Message Authentication Code (MAC). In this regard, explain which of the two concerns mentioned in part a) will MAC be able to address. c) What flaw in MAC prevents it from holding up in a court of law?  

State true or false for each of these (no explanation requir…

State true or false for each of these (no explanation required): a) If an Autonomous System (AS) learns of 4 different routes to a destination prefix, it need not announce all 4 to its neighbor.  b) The link layer is implemented in the hosts as well as the routers. c) Single bit parity cannot correct any error. d) 1000Base-T is the 1000 Mbps on fiber standard. e) In Bellman-Ford algorithm, the nodes share information about the neighbors with the world.