Systems, methods and computer software are disclosed for supporting idle mode signaling reduction (ISR) core offload. In one embodiment a method includes providing an eNodeB co-located with a NodeB, and a User Equipment (UE) with ISR enabled; activating ISR when the UE goes idle and is switching between different Radio Access Technologies (RATs), and wherein UE connections are maintained with a Serving GPRS Support Node (SGSN) and a Mobility Management Entity (MME).

A method for registration is used in an access and mobility management function (AMF) redirection scenario. The registration method includes determining, by a first AMF selected, during AMF redirection, to serve a user equipment (UE), to protect a first message, and sending the protected first message to the UE, where the first message includes an authentication request message.

Accordingly, embodiments herein disclose a method for seamless service continuity. The method includes: receiving, from a first server (110a, 112a, 118), data packets related to the service; determining that the UE (102) locates in a service area where the service is provided by both the first server (110a, 112a, 118) and a second server (110b, 112b); establishing a connection of the UE (102) with the second server (110b) based on determining that the UE (102) locates in the service area; transmitting, to the first server (110a, 112a, 118), information related to the connection of the UE (102) with the second server (110b, 112b); receiving, from the first server (110a, 112a, 118), information including a notification which indicates a transfer of application context of the service to the second server (110b, 112b) is completed; switching the connection from the first server (110a, 112a, 118) to the second server (110b, 112b) based on receiving the information including the notification; receiving, from the first server (110a, 112a, 118), end data packets related to the service, in response to switching the connection; and continuing the service using the established connection with the second server (110b, 112b) based on the received end data packets.

One aspect provides a method performed by a radio access network node in a telecommunications network. The method comprises: responsive to detection of a trigger event associated with a wireless device having a connection to the telecommunications network via the radio access network node or seeking to establish or resume a connection to the telecommunications network via the radio access network node, selecting a core network user plane function for the connection to the telecommunications network; and initiating establishment of a user-plane tunnel for the connection between the radio access network node and the selected core network user plane function.

One aspect provides a method performed by a radio access network node in a telecommunications network. The method comprises: responsive to detection of a trigger event associated with a wireless device having a connection to the telecommunications network via the radio access network node or seeking to establish or resume a connection to the telecommunications network via the radio access network node, selecting a core network user plane function for the connection to the telecommunications network; and initiating establishment of a user-plane tunnel for the connection between the radio access network node and the selected core network user plane function.

The present disclosure provides a method for implementing communication continuity at a computer device acting as an application function (AF) device corresponding to user equipment (UE), the UE establishing a wireless connection to a source application server (AS) using allocated UE source network address information. The method includes: determining a data service migration from the source AS to a target AS; transmitting a network address translation (NAT) parameter to a session management function (SMF), so that the SMF determines a target user plane function (UPF)/protocol data unit (PDU) session anchor (PSA) for performing NAT translation on a received data packet according to the NAT parameter; and configuring a third NAT parameter for the target AS according to the NAT parameter, and migrating the data service from the source AS to the target AS, so that the target AS performs NAT translation on the data packet according to the third NAT parameter.

A method, system and computer readable media for reducing Packet Gateway (PGW) initiated signaling with a Serving Gateway (SGW) is presented. In one example embodiment a method for reducing Packet Gateway (PGW) initiated signaling with a Serving Gateway (SGW), includes determining by the PGW that a Packet Data Network (PDN) is undergoing S1-handover

with the SGW-relocation; buffering, by the PGW, bearer procedure messages and starting a guard timer; and re-attempting the buffered messages until a condition has been met.

The disclosed technology is directed towards preventing a handover of a Wi-Fi call to a Fifth Generation (5G) standalone cellular network. In one alternative, a 5G standalone usage setting is disabled on a mobile device when Wi-Fi calling is enabled on the mobile device. In another alternative, a 5G standalone usage setting is disabled on a mobile device when Wi-Fi calling is enabled on the mobile device and the mobile device is connected to a Wi-Fi network, which facilitates camping on a 5G standalone network when the mobile device is not connected to a Wi-Fi network. In yet another alternative, a 5G standalone usage setting is disabled on a mobile device when an evolved packet data gateway (ePDG) tunnel is set up on the mobile device, which similarly facilitates camping on a 5G standalone network when the ePDG tunnel is torn down.

A packet forwarding method includes that a session management network element sends a path identifier to a first device, where the first device includes an access network element corresponding to a protocol data unit (PDU) session and a user plane network element corresponding to the PDU session, the PDU session corresponds to a first terminal, the path identifier indicates a first path from the access network element to the user plane network element, the first path includes a part or all of a second path, and the second path is a path corresponding to a PDU session pre-established by the session management network element for a second terminal. The session management network element further sends, to the first device, identification information of a destination address corresponding to the path identifier.

Embodiments of the present disclosure provide methods and apparatus for indirect data forwarding. A method at a mobility management node comprises sending, to a serving gateway entity in the first system, a request for creating an indirect data forwarding tunnel. The request comprises an indication flag for indicating to the serving gateway entity that an indirect data forwarding tunnel is to be created with a user plane function entity in a second system. The method further comprises receiving a response for the request from the serving gateway entity.