Communication method, apparatus, and device

A communication method, applied to an application server (AS), wherein the method comprises:

• sending a first service data packet of a first service to a terminal device over a multicast session of a first mobile communication system;
• receiving first information from the terminal device, wherein the first information triggers the AS to send a second service data packet of the first service to the terminal device in a unicast transmission mode;
• and
• sending the second service data packet of the first service to the terminal device in the unicast transmission mode based on the first information.

A communication apparatus, applied to a terminal device and comprising:

• a non-transitory memory storage comprising instructions;
• and
• one or more processors in communication with a transceiver and the memory storage, wherein when the one or more processors execute the instructions they are configured to:
• receive a first service data packet of a first service from an application server (AS) over a multicast session of a first mobile communication system;
• and
• in response to the terminal device switching from the first mobile communication system to a second mobile communication system, send first information to the AS, wherein the first information is configured to trigger the AS to send a second service data packet of the first service to the terminal device in a unicast transmission mode.

A communication apparatus, applied to an application server (AS) and comprising:

• a non-transitory memory storage comprising instructions;
• and
• one or more processors in communication with a transceiver and the memory storage, wherein when the one or more processors execute the instructions they are configured to:
• send a first service data packet of a first service to a terminal device over a multicast session of a first mobile communication system;
• receive first information from the terminal device, wherein the first information triggers the AS to send a second service data packet of the first service to the terminal device in a unicast transmission mode;
• and
• send the second service data packet of the first service to the terminal device in the unicast transmission mode based on the first information.