Optionally, the reason why the UE cannot obtain the session parameter of the first application may include: a UE policy in the UE is not timely updated, and consequently, the UE cannot obtain the session parameter of the first application; or the first application has no requirement for some session parameters, and consequently, the session parameters of the first application cannot be obtained by the UE.
In addition, when the UE needs to transmit data of the first application, and no session corresponding to the first application exists in the UE, or when the first application binds the established session of the UE, the UE can determine, by using the same method, that the first application is not associated with the session parameter of the first session.
For example, session parameter types corresponding to the first application include: the S-NSSAI parameter, the DNN parameter and the SSC mode. If the UE cannot obtain any one or more of the foregoing three types of session parameters corresponding to the first application, the UE can determine that the first application is not associated with the session parameter of the first session.
S207. In response to the UE obtaining the indication information, the UE transmits the data of the first application through the first session, where the indication information indicates that the session parameter of the first session can satisfy the application that is not associated with the session parameter of the first session.