A splitting method, comprising: Sending, by a base station, an authentication indication to user equipment, wherein the authentication indication is used to instruct the user equipment to initiate authentication to a wireless local area network WLAN, the base station implements wireless communication based on a cellular radio communications technology, and the WLAN implements wireless communication based on a wireless fidelity Wi-Fi access technology; Acquiring, by the base station, an authentication status report indicating that the user equipment is admitted to the WLAN; Determining, by the base station according to the authentication status report, that the base station exchanges, with an access point of the WLAN, a first data stream of a data stream to be processed, wherein the data stream to be processed is a data stream that is to be sent by the base station to the user equipment or a data stream that is to be sent by the user equipment to the base station; characterised in that the method further comprises: acquiring, by the base station, a key through the authentication, wherein the key is used by the user equipment and the base station to encrypt/decrypt a second data stream of the data stream to be processed, and the second data stream is a data stream that is sent by the base station to the user equipment based on the cellular radio communications technology; indicating, by the base station to the access point of the WLAN, that the user equipment is a trusted device, wherein the trusted device represents that the user equipment is admitted to the access point of the WLAN through the authentication; and sending, by the base station, the key to the access point of the WLAN, wherein the key is further used by the user equipment and the access point of the WLAN to encrypt/decrypt the first data stream. Sending, by a base station, an authentication indication to user equipment, wherein the authentication indication is used to instruct the user equipment to initiate authentication to a wireless local area network WLAN, the base station implements wireless communication based on a cellular radio communications technology, and the WLAN implements wireless communication based on a wireless fidelity Wi-Fi access technology; Acquiring, by the base station, an authentication status report indicating that the user equipment is admitted to the WLAN; Determining, by the base station according to the authentication status report, that the base station exchanges, with an access point of the WLAN, a first data stream of a data stream to be processed, wherein the data stream to be processed is a data stream that is to be sent by the base station to the user equipment or a data stream that is to be sent by the user equipment to the base station; characterised in that the method further comprises: acquiring, by the base station, a key through the authentication, wherein the key is used by the user equipment and the base station to encrypt/decrypt a second data stream of the data stream to be processed, and the second data stream is a data stream that is sent by the base station to the user equipment based on the cellular radio communications technology; indicating, by the base station to the access point of the WLAN, that the user equipment is a trusted device, wherein the trusted device represents that the user equipment is admitted to the access point of the WLAN through the authentication; and sending, by the base station, the key to the access point of the WLAN, wherein the key is further used by the user equipment and the access point of the WLAN to encrypt/decrypt the first data stream. acquiring, by the base station, a key through the authentication, wherein the key is used by the user equipment and the base station to encrypt/decrypt a second data stream of the data stream to be processed, and the second data stream is a data stream that is sent by the base station to the user equipment based on the cellular radio communications technology; indicating, by the base station to the access point of the WLAN, that the user equipment is a trusted device, wherein the trusted device represents that the user equipment is admitted to the access point of the WLAN through the authentication; and sending, by the base station, the key to the access point of the WLAN, wherein the key is further used by the user equipment and the access point of the WLAN to encrypt/decrypt the first data stream.