Techniques for handling requests from a remote device are disclosed. A server receives a first unsolicited activation request from a first device of a plurality of devices. A probabilistic hash filter, associated with a data set, is queried using a first identifier associated with the first device. In response, a first result is received from the probabilistic hash filter indicating that the first device is not ready for activation. In response to receiving the first result, a back-off indication is transmitted to the first device.