Various embodiments of the present technology allow multi-realm support at US-CSCF to IMS by the same I/S-CSCF nodes. Some embodiments allow for a registration message to be received from an IMS client. The registration message can be used to establish, through an Internet Protocol Multimedia Subsystem (IMS) core network, a service between a first endpoint associated with a first realm and a second endpoint associated with a second, different realm. The registration message can be translated so that the second endpoint believes the first endpoint is associated with the second realm before being transmitted to the second endpoint. Upon receiving a successful IMS registration message from the IMS core network, a binding can be created between the first endpoint and the second endpoint.

A communication device for handling channel access in an unlicensed band comprises a storage device for storing instructions and a processing circuit coupled to the storage device. The processing circuit is configured to execute the instructions stored in the storage device. The instructions comprise receiving an uplink (UL) grant from a network, wherein the UL grant indicates the communication device to perform an UL transmission in a transmission time interval (TTI); performing a listen-before-talk (LBT) procedure on a first carrier in response to the UL grant; and aborting the LBT procedure, when the communication device senses the first carrier to be busy before the TTI according to the LBT procedure.

A communication device for handling channel access in an unlicensed band comprises a storage device for storing instructions and a processing circuit coupled to the storage device. The processing circuit is configured to execute the instructions stored in the storage device. The instructions comprise receiving an uplink (UL) grant from a network, wherein the UL grant indicates the communication device to perform an UL transmission in a transmission time interval (TTI); performing a listen-before-talk (LBT) procedure on a first carrier in response to the UL grant; and aborting the LBT procedure, when the communication device senses the first carrier to be busy before the TTI according to the LBT procedure.

A location management device function is provided in an access network, and a base station identifies and authenticates a terminal device permitted to perform base station loopback communication on the basis of identification information on the terminal device received from the terminal device. With this configuration, provided is a communication control method and the like for the base station device that has lost connectivity to a core network, to permit only specific terminals to perform base station loopback communication.

A user equipment (UE) may receive, during release from a radio access network (RAN), resource information associated with attaching to the RAN, wherein the resource information is received based on the device being authenticated. The UE may store the resource information in a data structure associated with the UE, and may receive, when the UE includes a payload of data packets to transmit to the RAN, a signal from the RAN. The UE may determine, based on the signal, whether the RAN is a same RAN that provided the resource information, and may determine whether a strength of the signal from the RAN satisfies a threshold when the RAN is the same RAN that provided the resource information. The UE may attach to the RAN when the strength of the signal satisfies the threshold, and may provide the payload to the RAN via a random access channel of the RAN.

Systems and methods are provided to support hypernumber portability for a hypernumber number corresponding to an electronic device. The electronic device may include an installed application to facilitate hypernumber portability. To this end, when the electronic devices connects to a wireless network, the electronic device may request a vehicle identification. If the wireless network is a vehicle-based network, the electronic device may receive the vehicle identification from an on-board node. When the received vehicle identification indicates that the electronic device has changed locations, the electronic device may communicate with a hypernumber database and/or a hypernumber server to update a dynamic phonebook. As a result, as the electronic device traverses a transport network, the dynamic phonebook may maintain updated location and call routing information for the electronic device.

Systems and methods are provided to support hypernumber portability for a hypernumber number corresponding to an electronic device. The electronic device may include an installed application to facilitate hypernumber portability. To this end, when the electronic devices connects to a wireless network, the electronic device may request a vehicle identification. If the wireless network is a vehicle-based network, the electronic device may receive the vehicle identification from an on-board node. When the received vehicle identification indicates that the electronic device has changed locations, the electronic device may communicate with a hypernumber database and/or a hypernumber server to update a dynamic phonebook. As a result, as the electronic device traverses a transport network, the dynamic phonebook may maintain updated location and call routing information for the electronic device.

A method for triggering a registration procedure by a UE within a registration area of a wireless communication network is provided. The method includes receiving a TAI list in a registration accept message while performing a first registration procedure with the wireless communication network and determining when the UE is moved from a first cell in a first TAI belonging to a first PLMN to a second cell in a second TAI belonging to a second PLMN, determining that the UE is in an RRC inactive state, and automatically triggering a second registration procedure with the wireless communication network, in response to determining that the UE is moved from first cell in first TAI belonging to first PLMN to second cell in second TAI belonging to second PLMN.

A method for triggering a registration procedure by a UE within a registration area of a wireless communication network is provided. The method includes receiving a TAI list in a registration accept message while performing a first registration procedure with the wireless communication network and determining when the UE is moved from a first cell in a first TAI belonging to a first PLMN to a second cell in a second TAI belonging to a second PLMN, determining that the UE is in an RRC inactive state, and automatically triggering a second registration procedure with the wireless communication network, in response to determining that the UE is moved from first cell in first TAI belonging to first PLMN to second cell in second TAI belonging to second PLMN.

A network function and a method for associating a UE of a UE group to a PDU session with in a CN. The NF establishes a shared PDU session for the UE group before all of the UEs in the UE group register with the CN and binds a UE that has not yet registered with the CN to the shared PDU session when the UE registers with the CN, provided the UE will share at least one of a UL UP connection and a DL UP connection associated with the shared PDU session. The NF may be an SMF.