Hi, These are the common mistake for assignment 3:
Q1-a) Do not explaining about the MAC address. For example, some student wrote “To obtain the IP address”.
Q1-c) Some students just wrote that they could not find the response to packet 9 but did not explain why.
Q2-b) Some students wrote that since the DHCP servers and capturing host have IP addresses with different prefix, they should be in two different subnets. However, we need to have the subnet mask to be able to jugde. The good news is that we did not deduct the mark for those without mentioning msubnet mask.
Q3-b) There were a confussion for this part with iterative and recursive queries in DNS. However, the question was about the reason that a client contacts three different DNS servers instead of one.
Q3-c) There were students which wrote the TTL of IP layer.
Q4-b) The man in the middle attack was mentioned by some student as the vulnerability of self-signed certificate. However, since the self-signed certificate is from a root CA, it is trustable.