Method for connecting IMS-based service

摘要

The present specification provides a method for connecting an IP multimedia subsystem (IMS)-based service in a terminal. The method for connecting the IMS-based service, includes the steps of: setting a cause value denoting signaling or due to the IMS in an establishment cause field, when a session initiation protocol (SIP)-based message is required to be transmitted on a user plane for connecting the IMS-based service; transmitting a service request message of a non-access stratum (NAS) layer including service type (field) denoting signaling or due to a base station; and transmitting a radio resource control (RRC) connection request message including the set establishment cause field to the base station.

主权项

1. A method for transmitting a Radio Resource Control (RRC) connection request message, the method comprising:
receiving system information from a base station, the system information including an exception rule for an access class barring; determining whether to transmit the RRC connection request message according to the access class barring information, wherein if the RRC connection request message is related to a specific multimedia telephony (MMTEL) service and if the exception rule is related to the specific MMTEL service, determining that the RRC connection request message is not barred and transmitting the RRC connection request message; and if there is a need to connect an Internet Protocol Multimedia Subsystem (IMS) based service, setting a cause value indicating that it is caused by IMS, in an establishment cause field of the RRC connection request message.