encryption

Research Links

• Wikipedia: XOR Cipher
• Wikipedia: One Time Pad

Using a simple XOR function you can make a cipher which when used with a fixed key is easy to break. However if you use it with a one time pad that is truly random it is theoretically unbreakable.  If this methodology was used with say a simple microcontroller that had an extremely simple set of code on it that was open source then it might be very difficult to break indeed.   Anything as complex as Windows and Linux have to be assumed to be comprimised.