A service procedure of the DSDS product is described as follows: On a terminal, a SIM card 1 of a user initiates a data service by using a modem MODEM 1. The MODEM 1 first applies to an arbitration apparatus for a data service resource. The arbitration apparatus determines whether a high-priority service is performed at this time; if no high-priority service is performed at this time, the arbitration apparatus returns an acknowledgment response to the MODEM 1. Then, the MODEM 1 starts to perform the data service. The service resource herein is a system resource required for performing a related service, and includes but is not limited to a radio frequency device, such as a radio frequency chip, a radio frequency front end device, or an antenna. A mobile terminated voice service is received or a mobile-originated voice service is initiated by using a modem MODEM 2 on a SIM card 2, and the MODEM 2 applies to the arbitration apparatus for a voice service resource. The arbitration apparatus determines that a low-priority service is being performed by using MODEM 1, and then initiates a preemption request to the MODEM 1. After the MODEM 1 releases the service resource such as a radio frequency front end, the arbitration apparatus returns an acknowledgment message to the MODEM 2. Then, the MODEM 2 starts to initiate the voice service. After the voice service on the MODEM 2 ends, the arbitration apparatus is notified to release the service resource. The arbitration apparatus notifies the MODEM 1 that the service resource of the MODEM 2 is unoccupied. After receiving the notification that the resource of the MODEM 2 is released, the MODEM 1 re-initiates a data service procedure.