FIELD: information technologies.
SUBSTANCE: invention relates to interaction of combined call services with switching of channels and subsystem of Internet protocol multimedia (CSI), including combined call with channels switching (CS) and session of Internet protocol multimedia subsystem (IMS), in particular to method and system for communication between user equipment (CSI UE), which may simultaneously support CS call and IMS session, and user equipment (IMS UE), which may not maintain CSI and may only maintain IMS session. Multimedia gate control function (MGCF) executes interaction between information of functional capabilities between message of CS and message of IMS, so that IMS UE may process information of functional capabilities of UE by means of request/response of IMS session. When message of call request, which does not contain information of functional capabilities, is created from UE, which does not support exchange of information on functional capabilities, CSI server of applications (AS) sends request message to peer-to-peer UE, after insertion of assessed information on functional capabilities of UE into message of call request, and preserves information on functional capabilities of UE, being a partner for this UE.
EFFECT: processing of information of functional capabilities between UE in IMS.
32 cl, 12 dwg, 4 tbl
