In a second possible implementation, when determining that the message 3 is a message in the EDT process, the terminal device may determine that the terminal device is performing the uplink EDT process or performing the downlink EDT process. The terminal device may consider that the TBS of the message 3 is sufficiently large, so that the terminal device can send the channel quality information through the RRC message in the message 3. Alternatively, when the terminal device determines that the RRC message in the message 3 is an RRC early data request message or an RRC connection resume request message, the terminal device may consider that the TBS of the message 3 is sufficiently large, so that the channel quality information can be sent through the RRC message in the message 3. Correspondingly, when determining that the message 3 is a message in the random access process, the terminal device may determine that the TBS allocated by the network device to the message 3 is relatively small, and therefore, determine that the channel quality information cannot be sent through the RRC message in the message 3.

In the foregoing process, the terminal device determines, by determining a type of the message 3, whether the process is the uplink EDT process or the downlink EDT process. Because the TBS of the message 3 in the uplink EDT process or the downlink EDT process is usually sufficiently large, in most cases, it can be ensured that both the channel quality information and data of the terminal device are sent.