A secure wireless local or metropolitan area network and data communications device therefor are provided, where the device transmits plain text in an encrypted message including cipher text and an initialization vector. The device may include a seed generator for performing a one-way algorithm using a secret key, a device address, and a changing reference value for generating a seed. Further, a random initialization vector (IV) generator may be included for generating a random IV, and a key encrypter may generate a key sequence based upon the seed and the random IV. Additionally, a logic circuit may be included for generating cipher text based upon the key sequence and plain text, and a wireless communications device may be connected to the logic circuit and the random IV generator for wirelessly transmitting the encrypted message.