Abstract: According to one embodiment of present invention, there is provided a method of controlling access to a communication network. The method comprises receiving a request from a communication device to connect to the communication network, the request including a substantially unique identifier of the device, and determining whether the identifier is contained in a local device database of the network. Where it is determined that the identifier is not contained in the local database, the method further comprises authorizing the device to connect to the network, and at a subsequent update of the local device database, determining the status of the identifier from a shared device database, and updating the status of the determined identifier in the local device database with the determined status.