In this possible implementation, for example, the terminal device includes a water meter, a smoke alarm, a mobile phone, and a computer. The core network device may determine, based on service features of the water meter and the smoke alarm, that a category to which the water meter and the smoke alarm belong is the category of uplink service trigger, and determine, based on service features of the mobile phone and the computer, that a category to which the mobile phone and the computer belong is the category of the downlink service trigger. In addition, after separately determining the categories to which the water meter, the smoke alarm, the mobile phone, and the computer respectively belong, the core network device sends the categories to which the water meter, the smoke alarm, the mobile phone, and the computer respectively belong to the corresponding water meter, smoke alarm, mobile phone, and computer. In addition, the water meter, the smoke alarm, the mobile phone, and the computer all receive a configuration of a plurality of wake up signals sent by the network device. For the configuration of the plurality of wake up signals, refer to the foregoing Table 1. Wake up signals corresponding to the category of the uplink service trigger are a wake up signal 1, a wake up signal 2, a wake up signal 3, and a wake up signal 4, and wake up signals corresponding to the category of the downlink service trigger are a wake up signal 5, a wake up signal 6, a wake up signal 7, and a wake up signal 8, so that the water meter and the smoke alarm may determine, based on the category of the uplink service trigger to which the water meter and the smoke alarm belong, that to-be-monitored signals that the water meter and the smoke alarm need to monitor are the wake up signal 1, the wake up signal 2, the wake up signal 3, and the wake up signal 4, and monitor the wake up signal 1, the wake up signal 2, the wake up signal 3, and the wake up signal 4; similarly, the mobile phone and the computer may determine, based on the category of the uplink service trigger to which the mobile phone and the computer belong, that to-be-monitored signals that the mobile phone and the computer need to monitor are the wake up signal 5, the wake up signal 6, the wake up signal 7, and the wake up signal 8, and monitor the wake up signal 5, the wake up signal 6, the wake up signal 7, and the wake up signal 8. In this way, when the core network device pages the mobile phone by using the wake up signal 5, the wake up signal 6, the wake up signal 7, and the wake up signal 8, for the water meter, the smoke alarm, the mobile phone, and the computer that are monitoring the wake up signals, only the mobile phone and a notebook computer can detect the wake up signal 5, the wake up signal 6, the wake up signal 7, and the wake up signal 8, and are woken up by the wake up signals, and neither the water meter nor the smoke alarm detects the wake up signal 5, the wake up signal 6, the wake up signal 7, and the wake up signal 8, and is woken up. This reduces false alarm probabilities of paging of a watch and the smoke alarm, thereby reducing power consumption of the watch and the smoke alarm that are not paged.