Method and system for implementing domain selection during the terminated call

A system for implementing domain selection during a terminal call, comprising:

• an application server (AS), configured to send a query request message to a home subscriber server (HSS) and to select a domain to which a call message is to be routed according to information of a called terminal and/or a network accessed by the called terminal fed back by the HSS;
• the HSS, configured to query a packet switching (PS) domain mobility management network element to obtain the information of the called terminal and/or the network accessed by the called terminal in the call request message, and to feed back the obtained information of the called terminal and/or the network accessed by the called terminal to the AS;
• and
• the PS domain mobility management network element;
• wherein the PS domain mobility management network element is a mobility management entity (MME) and/or a serving general packet radio service support node (SGSN), and the information of the network accessed by the called terminal comprises IMS VOIP capability of a network area in which the called terminal currently registers, and the MME/SGSN sends a message to the HSS to indicate the IMS VOIP capability only when the HSS queries the change of the IMS VOIP capability, then the MME/SGSN sends a message to the HSS to indicate the IMS VOIP capability.