A method for enrolling devices in a security system based upon RFID techniques. The method prevents unauthorized devices from engaging in communications by and between the various devices in the security system. While the security system may have long RF range during normal operation, the RFID readers of the security system reduce their read range during an enrollment operation. A user must be physically proximate to an RFID reader to enroll any device. The controller has an associated master key RFID transponder containing at least one code necessary for enabling enrollment of an RFID reader. This master key RFID transponder can only be read during enrollment. RFID transponders and RFID readers also exchange at least one code during the enrollment of RFID transponders. The codes can enable encrypted communications during normal system operation.