Hello Chris, I wanted to check if my reasoning is correct for the following questions: 1.The design offers a good balance because 1 in 2^16 is still very low probability and a longer checksum would add to more overhead data addition 9. The network layer only cares about sending the packet to the right destination,and errors in data's payload are taken care by other layers 10. (the timeout part) we need to design a timeout to wait for until NACK is received correctly and if the timer is finished then sender knows it works correctly. Thank you for your time for looking at these questions