In this research, the data flow from a field programmable gate array (FPGA) and the advanced encryption standard with the 256 bit key (AES-256) were used to make an electromagnetic side-channel attack. The FPGA board was a Diligent Nexys-4 with Artix-7 FPGA and partially succeeded. With only 2000- 3000 electromagnetic (EM) tracks a few sub keys were successfully removed from AES-256. The remaining key assumptions were classified and shown in a chart accordingly. In addition to this, the tests conducted included an attack on an isolated hardware field in the AES algorithm by designing a single 8-bit data block, the first round and Sub Bytes. The acquisition of data was corrupted every time someone was plugged in e.g. a cell phone charger or a laptop-charger in the nearby rooms. Longer tests are hard to perform because of random interference. In order to detect interference, the experiment was constantly supervised. For future tasks, the lateral channels attack will require more EM-trace data points, more EM-tracks, faster oscilloscope, lower-pass filters and a wider bandwidth amplifier.

Keywords : Electromagnetic Side-Channel Attack; AES- 256; Artix-7; FPGA; Differential Analysis.