Some demonstrative embodiments include devices, systems and/or methods to establish a connection to the Internet via a local gateway (L-GW) function for a LIPA or a SIPTO@LN. The establishment of the connection to the Internet may be performed, for example, by at least one of an E-RAB SETUP procedure, an INITIAL CONTEXT SETUP procedure, an INITIAL UE MESSAGE procedure or an UPLINK NAS TRANSPORT procedure.

It is presented a method for error handling during a Mobile Terminated, MT, call to a User Equipment, UE, in a cellular system. The method is performed by a network device being an alternative Mobility Management Entity, MME, of the cellular system. The method comprises the steps of: failing to forward a paging request to a serving MME, at which the UE is registered; and paging the UE using a Circuit Switched, CS, paging. A corresponding network device, User Equipment, computer program and computer program product are also presented.

A method, a system, and a non-transitory storage medium are described in which a radio frequency band selection service is provided. The radio frequency band selection service may include a default service band, a default coverage band, and a threshold value that allows an end device to select a radio frequency band to camp on when in an idle mode, select a radio frequency band to obtain service when in a connected mode, and select stand-alone or non-stand-alone services.

A data transmission method and apparatus are disclosed. The method includes: determining, by a source base station of a terminal in a handover process, first data and a radio air interface protocol sequence number of a data unit used to carry the first data, where the first data includes data that is not acknowledged by a terminal for correct reception during data transmission between the source base station and the terminal. The method further includes sending, by the source base station, the first data and the radio air interface protocol sequence number to a target base station; where the core network connected to the target base station is different from the core network connected to the source base station.

A transition region can be defined for a first network segment that can provide wireless communication services using a first radio access technology (RAT) and a second RAT and that supports Internet protocol (IP) packet-based voice calls. The transition region can be defined based at least in part on a first coverage area of the first network segment and a second coverage area of a second network segment that does not support IP packet-based voice calls and does not support a first handoff mechanism based on the first RAT. A network node can be notified about an IP packet-based voice call involving a user equipment (UE) that is receiving service from the first network segment using a first RAT. Upon determining that the UE is located within the transition region, the network node can cause the UE to be switched to a second RAT for the IP packet-based voice call.

A radio access network handover method of a base station in a 5G radio access network (5G-RAN) is are disclosed. The method comprising: determining handing over a user equipment (UE) to an Evolved Universal Terrestrial Radio Access Network (E-UTRAN); transmitting a handover requirement message to an Access and Mobility Management Function (AMF); receiving a handover command message from the AMF and transmitting the handover command message to the UE, the handover message such that the UE is handed over from the 5G-RAN to the E-UTRAN; and performing indirect data forwarding to a base station in the E-UTRAN.

A key generation method includes determining, by an access and mobility management function node, key-related information. The method also includes sending, by the access and mobility management function node, a redirection request message to a mobility management entity. The redirection request message includes the key-related information, and the redirection request message is used to request to hand over a voice service from a packet switched (PS) domain to a circuit switched (CS) domain. The method further includes receiving, by the mobility management entity, the redirection request message. The method additionally includes generating, by the mobility management entity, an encryption key and an integrity protection key for the voice service based on the key-related information.

Embodiments of the present application relate to methods and apparatuses for a mobility robustness optimization (MRO) mechanism of an inter-radio access technology (RAT) handover procedure. According to an embodiment of the present application, a method can include: receiving a mobility command message from a source new radio (NR) cell, wherein the mobility command message includes an identifier (ID) of a target cell, and the target cell is at least one of an evolved universal terrestrial radio access network (E-UTRAN) cell and an universal terrestrial radio access network (UTRAN) cell; determining whether a timer for initiating failure recovery based on triggering a measurement report (e.g., timer T312) is running; and in response to the timer being running, stopping the timer. Furthermore, radio link failure report (RLF) information is transmitted to a network in response to the failure of Inter-RAT handover from NR to E-UTRAN and UTRAN.

An apparatus for wireless communication of a user equipment (UE) is disclosed. The apparatus may include a memory and at least one processor coupled to the memory. The at least one processor may be configured to receive a paging signal associated with an mobile terminating (MT) internet protocol (IP) multimedia subsystem (IMS) voice session. The at least one processor may be further configured to send a session initiation protocol (SIP) message in response to the paging signal. The at least one processor may be further configured to receive a second SIP message indicating SIP failure. The at least one processor may be further configured to determine whether the second SIP message indicates a network failure or a global failure. The at least one processor may be further configured to establish a connection with a different RAT network when the second SIP message indicates a network failure or a global failure.

Embodiments of the present disclosure provide methods and apparatuses for handover. A method performed by a source NG-RAN, base station in a wireless communication network, for handling handover of a User Equipment, UE, in which the method includes obtaining an indication information which indicates the IP Multimedia Subsystem, IMS, voice call initiation. The method further includes performing a handover policy to prioritize handover or redirection to an Evolved-Universal Terrestrial Radio Access Network, E-UTRAN, base station over handover to a target NG-RAN base station.