For our theoretical tests we set up two identical computers which we linked together through a Netgear Prosafe GS105 Gigabit switch. We then transferred two large 5GB folders of files across the network, one filled with three large video files and one filled with thousands of smaller files.
The time taken to transfer the data was recorded and divided by the size of the folder to give an average transfer speed in MB/sec. Each test was repeated three times and the three results averaged to give a reliable result.