Delivering communication services is provided. A request for a mobile number from a mobile number authority is received from a subscriber. In response to receiving the request from the subscriber, the mobile number is assigned to the subscriber and sent to the subscriber. A request to register with the mobile number authority is received from a communication service provider. In response to receiving the request from the communication service provider, the communication service provider is registered with the mobile number authority. The mobile number from the mobile number authority may be used by the subscriber to subscribe at the same time to a plurality of communication services for a mobile device from a plurality of different communication service providers registered with the mobile number authority.

In a user equipment of a wireless communication system, a method for signal transmission and reception may include: sending a request for a Circuit Switched voice network (CS) service to a Gateway Mobile Switching Center (GMSC) to send and receive data to and from a second user equipment; and receiving a call reject response corresponding to the service request from the GMSC, wherein the call reject response is sent by an entity in a core network of the second user equipment. According to an embodiment, it is possible to provide a suitable service to a sender terminal making a CS service request to a receiver terminal having subscribed only to a PS service without increasing network load.

The present disclosure relates to synchronizing a temporary identity in the UE and the network when the UE is RRC Inactive state over 3GPP access and temporary identity of the UE is changed over a Non-3GPP access in a scenario when the UE is connected to the same AMF via 3GPP and non-3GPP access.

The present disclosure relates to network slice access control methods. One example method includes receiving, by an access and mobility management function network element, first information from a session management function network element, where the first information is associated with an authentication failure of a network slice, and sending, by the access and mobility management function network element, second information to a terminal device based on the first information, where the second information is used to reject access of the terminal device to the network slice.

A method includes after receiving a first non-access stratum (NAS) security mode command (SMC) message sent by an initial access and mobility management function (AMF), a user equipment (UE) stores a first NAS security context; the UE receives a second NAS SMC message sent by a second AMF, where the message carries indication information used to indicate the UE to use the first NAS security context; and the UE uses the first NAS security context as a current NAS security context based on the indication information. According to the method for mobility registration provided in this application, when receiving the second NAS SMC message sent by the second AMF, the UE uses the first NAS security context as the current NAS security context, and then processes the second NAS SMC message, so that the NAS security contexts on the UE and the second AMF are consistent.

The present disclosure relates to a communication method and system for converging a 5th-Generation (5G) communication system for supporting higher data rates beyond a 4th-Generation (4G) system with a technology for Internet of Things (IoT). The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services. The disclosure proposes, when a UE is registered in an AMf which does not support ATSSS (registration procedure), a method by which, an old AMF identifies the registration and releases an MA PDU session and a method by which the UE identifies the registration and releases the MA PDU session in a wireless communication system according to an embodiment.

The disclosure relates to a 5th generation (5G) or 6th generation (6G) communication system for supporting a higher data transmission rate. A method performed by an access and mobility management function (AMF) in a public land mobile network (PLMN) providing disaster roaming service is provided. The method includes determining whether a disaster condition has ended in a previous PLMN associated with a user equipment (UE) which is registered for the disaster roaming service, in response to determining that the disaster condition has ended and the UE has an emergency protocol data unit (PDU) session, generating a message indicating that the UE is registered for emergency service, and transmitting, to the UE, the message.

Systems and methods for MME adaptive selection are described. The method includes: initializing a health checkup algorithm at an eNodeB for each MME connected to as per configuration values; starting a health check timer for each MME; continuing with an Initial Attach procedure for incoming calls based on SAE-Temporary Mobile Subscriber Id (S-TMSI), (Globally Unique MME Identifier) GUMMEI, or capacity/load balancing considerations; on every UE attach attempt, incrementing a total calls count; and on every S1 AP Error Indication/no response from an ME, incrementing a total fail calls count; determining when the health check timer for an MME expires; calculating a failed calls/total calls percentage value. Based on the value of the timer, appropriate action is taken.

This application provides a network slice access control method, including: determining, by an access and mobility management function network element, first allowed network slice selection assistance information of a terminal device in a registration process to register the terminal device to a network; learning, by the access and mobility management function network element, of an authentication failure of a first network slice corresponding to first single network slice selection assistance information from the first allowed network slice selection assistance information.

A handover method, a device, and a system to ensure that after an access and mobility management function (AMF) entity determines to no longer serve some terminals, a current ongoing procedure of a terminal in these terminals is not interrupted. The method includes: receiving, by a target mobility management entity, a message related to a target terminal; and sending, by the target mobility management entity, the message related to the target terminal to a source mobility management entity that currently serves the target terminal.