Sender and receiver must have some way of assuring that they use the same random numbers in sequence. Elementrix Technologies claims to have found a secure way to synchronize, and to resynch if sender and receiver later lose contact. The method is still secret while patents are pending, so the algorithms have received no scrutiny from outside cryptographic experts. While one-time pads may be inherently secure, subtle weaknesses could be hidden in the synchronization algorithms. The POTP technology generates a random key as long as the message to be encrypted, so the encryption step can be computationally simple.
Cryptographic textbooks suggest XOR'ing the bits in message and key.
The method can be implemented simply in either software or hardware. Timing is everything. Elementrix relaunched the news of their unbreakable, one-time pad technology into the media glare ignited by news of Netscape's two cracks and a bug. They offer both a secure FTP and secure email application, for Windows only at this point, with more platforms promised for the future. This technology did not originate in the USA and so may be free of US export restrictions.