Devices, methods, use user equipment (UE), core network devices, evolved node B (eNB), and storage media for UE provisioning are described. In one embodiment, processing circuitry of a mobility management entity (MME) decodes a non-access stratum (NAS) message comprising a detach request associated with a first user equipment (UE) and determines that the detach request is received from the UE without integrity protection. The MME then analyzes one or more additional criteria associated with the detach request in response to confirmation that the detach request message is received from the UE without the integrity protection, and manages an evolved packet system (EPS) mobility management (EMM) registration state for the first UE based on analysis of the one or more additional criteria. Various different criteria and associated EMM registration state management operations are described. Additional corresponding UE operations are also described.

A method and system in which upon occurrence of a P-CSCF failure, a network sends an IMS reregistration request message to a UE. An S-CSCF or an AS monitors a P-CSCF to detect occurrence of a failure in the P-CSCF. Upon detecting the occurrence of a P-CSCF failure, the S-CSCF or the AS sends a request message for IMS reregistration to the UEs being served by the failed P-CSCF. In this manner, the UE can continuously receive the service even though a failure occurs in the P-CSCF.

A method and system in which upon occurrence of a P-CSCF failure, a network sends an IMS reregistration request message to a UE. An S-CSCF or an AS monitors a P-CSCF to detect occurrence of a failure in the P-CSCF. Upon detecting the occurrence of a P-CSCF failure, the S-CSCF or the AS sends a request message for IMS reregistration to the UEs being served by the failed P-CSCF. In this manner, the UE can continuously receive the service even though a failure occurs in the P-CSCF.

A User Equipment (UE) including a wireless transceiver and a controller is provided. The wireless transceiver performs wireless transmission and reception to and from a first cellular station and a second cellular station. The controller continues to send or receive UP data to or from the first cellular station via the wireless transceiver after receiving a handover command message for a handover of the UE from the first cellular station to the second cellular station, and receives a Radio Resource Control (RRC) request message from the second cellular station via the wireless transceiver after sending a handover complete message to the second cellular station. Also, the controller detaches from the first cellular station in response to receiving the RRC request message.

A User Equipment (UE) including a wireless transceiver and a controller is provided. The wireless transceiver performs wireless transmission and reception to and from a first cellular station and a second cellular station. The controller continues to send or receive UP data to or from the first cellular station via the wireless transceiver after receiving a handover command message for a handover of the UE from the first cellular station to the second cellular station, and receives a Radio Resource Control (RRC) request message from the second cellular station via the wireless transceiver after sending a handover complete message to the second cellular station. Also, the controller detaches from the first cellular station in response to receiving the RRC request message.

A control system enables re-registration of user equipment (UE) on an alternative network in the event of a partial failure of a network (VPLMN) for wireless communication. An access and mobility management function (AMF) manages the communication to user equipment (UE) via network slices (1,2,3). A slice priority management function (SPM) receives data indicative of a change in the network's ability to maintain the instantiated network slices and determines to reduce services via affected network slices. Before said slice reduction, the access and mobility management function is informed and sends a slice reduction message to the user equipment. In the UE an alternate network selection function (ANSF) receives the slice reduction message and selects an alternate network based on the user information (USIM) and the slice reduction information, and triggers registration on the selected alternate network for transferring at least part of the affected services to a network slice of the selected alternate network.

A control system enables re-registration of user equipment (UE) on an alternative network in the event of a partial failure of a network (VPLMN) for wireless communication. An access and mobility management function (AMF) manages the communication to user equipment (UE) via network slices (1,2,3). A slice priority management function (SPM) receives data indicative of a change in the network's ability to maintain the instantiated network slices and determines to reduce services via affected network slices. Before said slice reduction, the access and mobility management function is informed and sends a slice reduction message to the user equipment. In the UE an alternate network selection function (ANSF) receives the slice reduction message and selects an alternate network based on the user information (USIM) and the slice reduction information, and triggers registration on the selected alternate network for transferring at least part of the affected services to a network slice of the selected alternate network.

This disclosure is related to a procedure of handling UE (100) behavior when the UE (100) is attached for emergency services. More specifically this disclosure defines the UE (100) behavior when the UE (100) is registered to a PLMN or two different PLMN via 3GPP access network and non-3GPP access network and UE (100) has is registered for emergency service over one of the 3GPP access network or non-3GPP access network.

Methods, apparatus and systems for backward compatible multi-access protocol data unit session (PDU) registration and deregistration are described. One method of digital communication includes establishing, by a session management function operating in a communication network, a PDU session for a wireless device and transmitting, upon successfully establishing the PDU session, a registration request to a network-side function to register a context of a PDU session of the wireless device with the network-side function, wherein the registration request identifies a set of session management functions that includes the session management function.

Methods, apparatus and systems for backward compatible multi-access protocol data unit session (PDU) registration and deregistration are described. One method of digital communication includes establishing, by a session management function operating in a communication network, a PDU session for a wireless device and transmitting, upon successfully establishing the PDU session, a registration request to a network-side function to register a context of a PDU session of the wireless device with the network-side function, wherein the registration request identifies a set of session management functions that includes the session management function.