Systems, methods and articles of manufacture to perform an operation comprising receiving, from one of a plurality of stations, a message which includes at least a random number and a first hash value of the random number concatenated with a first key, comparing the first hash value to one or more second hash values, wherein each second hash value is generated by hashing the random number concatenated with one of a plurality of second keys and wherein each second key corresponds to a registered device of a device identification system, upon determining the first hash value matches one of the second hash values, determining an identity of the mobile device based on the corresponding second key, and based on the location of the station which sent the message, assigning a location to the mobile device.