This question is about Kerberos Version 4 from Table 15.1. Give explanations for the following:

(a) Explain what would be the disadvantage if the lifetime in the service-granting ticket was very long and what would be the disadvantage if the lifetime was very short.

(b) Suppose V is a file server and C wants to get files from V . One purpose of sending EC,V in round (4) is that V can encrypt files using EC,V to mantain confidentiality. Suppose C does not care about the confidentiality of these files i.e. he does not care if BG is able to read these files. In this situation, the files do not need to be encrypted with EC,V . In this situation, does EC,V still need to be included in round (4)? Give a YES/NO answer and then briefly explain your answer.

(c) Suppose BG captures (4) i.e. the communication from T GS to C. Will he be able to pose as C and get service from V ? Give a YES/NO answer and then briefly explain your answer.

please answer them briefly as soon as possible.