5. ARP is especially suspected to ""spoofing"" because an arbitrary machine can answer an ARP broadcast. Revise the example of software by adding checks that detect when (a) two or more machines answer request for a giving IP address, (b) a machine receives an ARP binding for its own IP address, and (c) a single machine answer requests for a multiple IP addresses.

6. As an alternative solution to the spoofing problem mentioned in the previous exercise, modify the example software by adding a check to ensure that the hardware address reported in field SHA of the ARP packet matches the hardware address in the source field of the hardware frame. what are the advantages and dis advantages of each approach?