The following applet contains two programs. The first one is a finite field calculator which allows arithmetic over extension fields of GF(2). To create a calculator for a specific field choose the degree of the extension and a primitive polynomial from the list and press the "Calculator" button. Any number of calculators can be run in parallel.
The second program is a Reed-Solomon encoder/decoder simulator. To create an instance of this program select again the field and press the "Reed-Solomon" button. Next select the code parameters (the code length N, error-correcting capability t and starting index j_0) and press the "Encoder/Decoder Simulation" button. A codeword is generated based on a random information word. A random set of t errors is generated and added to the codeword. The result is then decoded. The user can change the number of errors and edit the error sequence.