There is disclosed a security device for use in a wireless network comprising a plurality of base stations that communicate with a plurality of mobile stations. The security device prevents unprovisioned mobile stations from accessing an Internet protocol (IP) data network through the wireless network. The security device comprises a first controller for receiving from the unprovisioned mobile station an IP data packet comprising an IP packet header and an IP packet payload and encrypting at least a portion of the IP payload. The security device also comprises a second controller for determining that the unprovisioned mobile station is, in fact, unprovisioned. In one embodiment, the first controller comprises a data processor that executes an encryption program stored in a memory associated with the data processor.