Support of handover of a wireless device (110) from a first Radio Access Network, “RAN”, (101) of a first Radio Access Technology, “RAT”, to a second RAN (111) of a second RAT that is different from the first RAT. Said RATs being supported by the wireless device (110). A first radio network node (102) is comprised in the first RAN (101) and said RANs (101, 111) are comprised in a cellular radio system (100). The first radio network node (102) sends (201; 301), to the wireless device (110), a request to return a compressed version of RAT capability information. The RAT capability information is associated with the wireless device (110) and at least one of the first RAT and the second RAT.

An electronic apparatus in a wireless communications system, and a mobility measurement method. The electronic apparatus includes a communications device and a mobility measurement device. The communication device is configured to separately perform dual-connection communication with two connection nodes by different carriers. The mobility measurement device is configured to perform mobility measurement, for determining a connection switching mode, on the connection nodes in the dual connections in a case in which connection service quality of at least one of the current dual connection nodes is lower than a preset level. The mobility measurement device is further configured to determine a reporting mode of a mobility measurement result according to the measurement condition of at least one of the current dual connection nodes.

An apparatus which can cause control information to be sent from a source base station to a target base station via a user plane.

Embodiments of the present disclosure provide a mobility management method, so as to effectively ensure normal communication between user equipment and a base station without using an anchor device, and ensure continuity of a service between the user equipment and a communication peer end. A specific solution is: establishing, by user equipment, a first substream to a communication peer end, when the user equipment is handed over from a first base station to a second base station, obtaining, by the user equipment, a second IP address when a second gateway and a first gateway are not a same gateway, establishing, by the user equipment, a second substream to the communication peer end after obtaining the second IP address, canceling, by the communication peer end, the first substream after the second substream is established, and releasing, by the first gateway, a first IP address after the first substream is canceled.

Access and Mobility Management Function, AMF, adapted for taking part in handover from a 5G system, 5GS, to an Evolved Packet System, EPS, an interface being provided between a Mobility Management Entity, MME, of the EPS and the AMF. The AMF being adapted for signalling with a Session Management Function and Packet Data Network, PDN, Gateway-Control plane, SMF and PGW-C, entity, the AMF being adapted for—providing a request (102d, 2-2a) to the SMF and PGW-C entity to provide a Session Management, SM, Context that also includes mapped EPS, Bearer Contexts (102d); —wherein for PDU Sessions with PDU Session type Ethernet or Unstructured, providing (102e1) a capability of a target MME of supporting a Non-IP PDN type to the PGW-C and SMF entity in the request (2-2a) to allow the PGW-C and SMF entity to determine whether or not to include an EPS Bearer context for non-IP PDN type; —transmitting the request (2-2a) to the SMF.

A wireless device is configured to support connections to one or more serving cells in a first radio access network (RAN), using a first radio access technology (RAT) and to one or more serving cells in a second RAN, using a second RAT that differs from the first RAT. The wireless device receives one or more handover commands as part of a handover of the wireless device to a base station in the first RAN, and determines, based on the one or more handover commands, that the wireless device is to revert from a currently configured Packet Data Convergence Protocol (PDCP) configuration to a PDCP configuration associated with the first RAT. The wireless device then reverts to the PDCP configuration associated with the first RAT, in response to said determining.

Methods and systems for controlling an SDN-based multi-RAT communication network. Embodiments herein disclose a wireless communication system, which can support/enable services that are currently being provided by multiple wireless communication systems. Embodiments herein disclose a wireless communication system based on SDN (Software Defined Networking). Embodiments herein disclose a network comprising of a generic control plane node. Embodiments herein disclose a method for communication between the proposed wireless communication system and existing UEs that are in use in today's 3GPP-LTE networks or IEEE 802.11 based WLANs without any changes in the mobile communication protocol. Embodiments herein disclose a method for providing services to the users, such as handover of a device from WLAN to 3GPP-LTE and vice versa.

Certain aspects of the present disclosure provide techniques for avoiding out of order uplink data reception upon data radio bearer (DRB) release or quality of service (QoS) flow addition. An exemplary method that may be performed by a user equipment (UE), includes obtaining an indication that a first data radio bearer (DRB) is released or handed over to a second DRB, wherein a first mapping maps a first quality of service (QoS) flow to the first DRB; obtaining a second mapping that maps the first QoS flow to a second DRB; editing service data adaptation protocol (SDAP) headers of uplink protocol data units (PDUs) in an uplink transmission buffer associated with the first DRB, based on a difference between a first configuration of the first DRB and a second configuration of the second DRB; and transmitting the uplink PDUs via the second DRB.

A method, a system and a device for maintaining user service continuity are provided in an embodiment of the present invention. The method includes prohibiting a UE from accessing a forbidden network before handover is complete when the UE needs to perform network handover if the UE adopts a SIM access technology, thus avoiding service interruption of a SIM user due to access to an incorrect network. A system and a device for maintaining user service continuity are provided in an embodiment of the present invention.

A method and apparatus for transmitting an indication in a wireless communication system is provided. An eNodeB (eNB) of a first system transmits an indication, which indicates that handover of a user equipment (UE) from the eNB to a radio network controller (RNC) of a second system is a necessary handover, to the RNC. In addition, a method and apparatus for receiving an indication for inter-radio access technology (RAT) unnecessary handover in a wireless communication system is provided. An eNB of a first system transmits a request for measuring, by a UE, quality of signals from the first system, and information related to the inter-RAT unnecessary handover, and receives an indication for the inter-RAT unnecessary handover.