In the table below we list several problems that may occur while data frames are transferred from one place to another. Whether the given type of errors is a serious problem or not, depends on the kind of network being used. We also list some possible remedies, e.g. fields that may be included in the data frame to detect errors and to solve the problem. For each problem, mark the appropriate remedy/ies with an X.
 
Frame checksum Header checksum Frame numbers Resend frame Send negative acknowledgement (Reject) Send frame of type ABORT and quit Sender timeout Receiver timeout Window field Numbered checkpoints (save data)
Bit errors in a frame
Lost frame
No acknowledgement received
Frame delivered to wrong address
Duplicate frames
Receiver buffer full
Frames out of sequence
Connection temporarily broken
Need to restart/resynchronise a long transfer
Sender/receiver appears to be dead
Protocol error (frame of wrong type in this situation)

No "correct answer" is given since trying to memorize this kind of a table makes no sense at all. Instead, try to understand the purpose of the various fields used in data frames.