A system for the encryption and decryption of data employing dual ported RAM for key storage to accelerate data processing operations. The drive cable is securely coupled at a second point to the pull of the second shade arrangement in a first segment of motion of the second point and in a subsequent second segment of motion of the second point is decoupled from the pull of the second shade arrangement, the coupling or decoupling taking place automatically a locking element. The additional challenge-response pairs are securely communicated between the PUF device and an authenticating server or other device for subsequent use in authentication. The cathodes may be of the micro-tipped or flat variety. The display unit displays a communication charge calculated on the basis of the counting result of the counting unit before the packet data is transmitted.