Abstract: Method and apparatus relating to a wireless device supporting 3GPP 4G and 5G radio interfaces and also supporting non-3GPP access, i.e., WiFi, for selecting a security gateway of a first type e.g., ePDG or a security gateway of a second type, e.g., N3IWF for accessing to the core network of first type, e.g., EPC or of a second type e.g., 5GC. As the access methods via ePDG and N3IWF are not the same, the wireless device has to determine based on information obtained by a function in the network and its capabilities whether to use an ePDG or an N3IWF for untrusted non-3GPP access. The wireless device may take into account in the selection whether it is connected to the Core network over 3GPP 4G or 5G radio access network. A corresponding apparatus claim is provided.

Abstract: A method of operating a wireless device according to some embodiments includes transmitting a message toward a core network identifying one or more network slices that are requested to be registered by the wireless device, and receiving a response from the core network. The response indicates whether the one or more network slices have been registered and includes information describing a plurality of lists of network slices. Each of the lists indicates a set of network slices that can be registered simultaneously by the wireless device.

Abstract: In one embodiment, a method performed by a wireless communication device comprises sending a registration request to a network node in a visited network and receiving a registration response comprising: (a) information that indicates one or more network slices in the visited network that can be used by the wireless communication device and (b) a link that can be activated by the wireless communication device to obtain a client that treats the wireless communication device as a SNPN client to enable the wireless communication device to make and/or receive calls to/from local wireless communication devices in the visited network. The method further comprises establishing a session with the visited network using one of the one or more network slices indicated by the information comprised in the registration response, activating the link using the session with the visited network, and, responsive thereto, downloading the client and executing the client.

Abstract: Systems and methods are disclosed herein for performing a controlled handover of a wireless device from an incoming access network to a cellular access network of a visited cellular network. In some embodiments, a method for handover of a wireless device from an incoming access network to a cellular access network of a visited cellular network while in roaming comprises, at the wireless device, sending a message to a core network of the visited cellular network. The message is related to a handover of the wireless device from the incoming access network to the cellular access network of the visited cellular network and comprises an incoming access indication. The incoming access indication is an indication of the incoming access network. The method further comprises, at the core network node, receiving the message and making a decision for the handover based on the incoming access indication.

Abstract: Providing Roaming Value Added Service (RVAS) network function for Home Public Land Mobile Network (HPLMN) is disclosed herein. In some embodiments, a Home Network Repository Function (H-NRF) in an HPLMN of a telecommunications network obtains information about a Home Control Network Function (NF) and a Roaming Control NF. A Visited NF in a Visited Public Land Mobile Network (VPLMN) sends a discovery request to the H-NRF in the HPLMN. The H-NRF receives the discovery request from the Visited NF in the VPLMN, and determines that, for the discovery request and the VPLMN, RVAS is applicable. The H-NRF selects the Roaming Control NF and the Home Control NF for the discovery request, and transmits, to the Visited NF, a response to the discovery request, the response comprising an address of the selected Roaming Control NF instead of an address of the selected Home Control NF.

Abstract: Systems and methods for simultaneous calling in a cellular communications system are disclosed. In one embodiment, a method performed by a first wireless communication device for simultaneous Internet Protocol (IP) Multimedia Subsystem (IMS) sessions between the first wireless communication device and two or more other wireless communication devices comprises establishing a first IMS session with a second wireless communication device and, while the first IMS session is ongoing and without placing the first IMS session on hold, establishing a second IMS session with a third wireless communication device. In this manner, simultaneous calling is enabled, which will, for example, allow machines to multitask in comparison to existing non-simultaneous calling.

Abstract: Methods and apparatus for bulk PDU session release between a wireless device and a control plane entity in a wireless system such as for example a 5G core network or similar is provided. The method comprises the wireless device determines that two or more Packet Data Unit, PDU, sessions established within the wireless system that are associated to at least one Data network identified by a Data Network Name, DNN, or to at least one Single Network Slice Assisted Information, S-NSSAI, should be released and transmits to a control entity of a core network, a Non-Access-Stratum, NAS, message indicating one of the at least one DNN or the at least one S-NSSAI for which the corresponding PDU sessions should be released all at once with a single message.

Abstract: Apparatuses and methods for P-CSCF to P-CSCF communication are disclosed. In one embodiment, a method implemented in a first proxy-call session control function (P-CSCF) node includes receiving, via a first user plane associated to an Internet Protocol (IP) Multimedia Subsystem (IMS) Protocol Data Unit (PDU) session for a user equipment (UE), a session initiation protocol (SIP) INVITE message; and as a result of the SIP INVITE message and based on a location of the UE relative to a first access gateway (AGW) associated to the first P-CSCF node, determining whether or not to initiate use of at least one of an additional second user plane and an additional second AGW for the IMS PDU session for the UE, the at least one of the second user plane and the second AGW being closer to the UE than the first user plane.

Abstract: Method and apparatus relating to a wireless device supporting 3GPP 4G and 5G radio interfaces and also supporting non-3GPP access, i.e., WiFi, for selecting a security gateway of a first type e.g., ePDG or a security gateway of a second type, e.g., N3IWF for accessing to the core network of first type, e.g., EPC or of a second type e.g., SGC. As the access methods via ePDG and N3IWF are not the same, the wireless device has to determine based on information obtained by a function in the network and its capabilities whether to use an ePDG or an N3IWF for untrusted non-3GPP access. The wireless device may take into account in the selection whether it is connected to the Core network over 3GPP 4G or 5G radio access network. A corresponding apparatus claim is provided.

Abstract: A method performed by a network node in a communications network, for handling of discovery of entrance points of a User Equipment (UE) to an IP Multimedia Subsystem (IMS) network, during an IMS Protocol Data Unit (PDU) session setup. The network node obtains a list of IMS entrance point instances, wherein the list of IMS entrance point instances comprises an address of each IMS entrance point instance and one or more transport protocols supported by each IMS entrance point instance. The network node generates, based on the obtained list of IMS entrance point instances, a configuration message for IMS entrance point discovery, comprising the address of the IMS entrance point instance and the one or more transport protocols supported by each IMS entrance point instance. The network node further provides to the UE the generated configuration message.

Abstract: Systems and methods are disclosed herein for ensuring network control of simultaneous access to network slices with application awareness. In one embodiment, a method performed in a cellular communications system comprises, at a wireless communication device, sending, to a Policy and Control Function (PCF) via an Access and Mobility Management Function (AMF), application identifiers (IDs) of applications used by the wireless communication device and receiving, from the PCF via the AMF, one or more User Equipment (UE) Route Selection Policy (URSP) rules that are based on the application IDs. The method further comprises, at the PCF, obtaining information about one or more mutually exclusive network slices, generating the one or more URSP rules based on the application IDs and the information about the one or more mutually exclusive network slices, and sending the one or more URSP rules to the wireless communication device via the AMF.

Abstract: Methods and apparatuses related to a P-CSCF server, UE, and PCRF server are disclosed. An indication may be obtained that the UE is at least dual-registered with an IMS via at least a first access network and a second access network. During the ongoing IMS session, an indication associated with the loss of bearer event for a first dedicated bearer for the ongoing IMS session may be received, the first dedicated bearer being associated with the first access network. As a result of at least the indication that the UE is at least dual-registered and receiving the indication associated with the loss of bearer event for the first dedicated bearer, a request is communicated to establish a second dedicated bearer for the second access network to continue the ongoing IMS session with the second access network.

Abstract: Systems and methods are disclosed herein for network-initiated slice-based handover in a cellular communications system. In one embodiment, a method in a cellular communications system comprises, at a network node in a core network of the cellular communications system, detecting a triggering event for a network slice handover for a session of a particular wireless communication device. The method further comprises, at the network node and responsive to detecting the triggering event, identifying a target network slice for the network slice handover and sending, to a Policy and Control Function (PCF) in the core network, a message that initiates a network slice handover of the session from a source network slice to the target network slice. The method further comprises, at the PCF, receiving the message that initiates the network slice handover and performing an action to cause the network slice handover.

Abstract: Embodiments of a method performed by an Interconnect Border Control Function (IBCF) in an Internet Protocol (IP) Multimedia Subsystem (IMS) network and corresponding embodiments of an IBCF are disclosed. In some embodiments, the method performed by the IBCF comprises receiving, from an IMS node in a virtual IMS network domain of a virtual IMS network operator, a Session Initiation Protocol (SIP) message that serves as a request for a leased IMS service. The SIP message comprises information that identifies the leased IMS service, information that identifies an IMS network slice, information that identifies the virtual IMS network operator, information that identifies one or more sub-services requested for the leased IMS service, and/or information that identifies an IMS network slice instance. The method further comprises making a decision as to whether to accept or reject the request based on the information comprised in the SIP message.

Abstract: A Voice Over Wifi (VoWifi) split Protocol Data Unit (PDU) Session handover is provided. In embodiments described herein, a VoWiFi session is established via a Non-3GPP N3IWF over a 5G Core, and a handover to 3GPP access through the 5G System is initiated. During handover and based on local configuration, the Packet Data Network Gateway-Control Plane (PGW-C) and Session Management Function (SMF) (PGW-C+SMF) accepts the PDU Session transfer towards the User Equipment (UE) and Next Generation Radio Access Network (NG-RAN) by means of setting up only the Quality of Service (QoS) Flow associated with a default QoS Rule. The PGW-C+SMF initiates set up of the QoS Flow for Internet Protocol (IP) Multimedia Subsystem (IMS) voice using the PDU Session Modification procedure after the NG-RAN successfully allocates resources for the transferred PDU Session and the confirmation has reached the PGW-C+SMF.

Abstract: Systems and methods are disclosed herein for Internet Protocol (IP) Multimedia Subsystem (IMS) support for non-International Mobile Subscriber Identity (IMSI) based Subscription Permanent Identifier (SUPI). In one embodiment, a method performed by a wireless communication device for IMS registration comprises deriving IMS registration information based on a non-IMSI based SUPI of the wireless communication device and sending an IMS registration request to an IMS node, the IMS registration request comprising the IMS registration information. In this manner, the non-IMSI SUPI can be reused for IMS access, e.g., when the network administrator does not plan to use an IP Multimedia Services Identity Module (ISIM), IMS Credential (IMC), or any future IMS-specific identity module in the deployed wireless communication devices. This simplifies the deployment by eliminating the need to manage and provision the IMS identity modules for a large number of wireless communication devices in use.

Abstract: Apparatuses and methods for resource isolation via associated identifiers are disclosed. In one embodiment, a method implemented in a user equipment (UE) configured with a first identifier and a second identifier includes determining that resources and data associated with the first identifier require end-to-end isolation from the resources and data associated with the second identifier; transmitting a registration message to a network node comprising the first identifier; and if the UE has existing connections associated with the second identifier, releasing the existing connections associated with the second identifier to provide end-to-end isolation of the resources and data when the first identifier is transmitted in the registration message.

Abstract: Apparatuses and methods tor an update service operation tor short message service, SMS, service are disclosed. In one embodiment, a method implemented in access and mobility management function, AMF, node (S104) includes performing an update service operation with a short message service function, SMSF, node to add or remove a first user equipment, UE, context information associated to a first access type, the update service operation indicating to the SMSF node the first access type to add or remove. In some embodiment, a method implemented in a short message service function, SMSF, node (S106) includes performing an update service operation with an access and mobility management, AMF, node to add or remove a first user equipment, UE, context information associated to a first access type, the update service operation indicating to the SMSF node the first access type to add or remove.

Abstract: Procedures are provided for robust handling of NAS request messages that contain a spurious information element (IE). The spurious information element could comprise a NAS message container containing a NAS message with the wrong procedure type, i.e., a procedure type that does not match the type of the parent NAS message. The spurious information elements could also comprise redundant IEs that are not necessary for the emergency services fallback request.

Abstract: Systems and methods are disclosed herein for counting registered User Equipments (UEs) in a network slice service area. In one embodiment, a method performed by an Access and Mobility Management Function (AMF) in a core network of a cellular communications system comprises receiving a registration request from a UE and, responsive to receiving the registration request from the UE, initiating a registration procedure and determining whether the registration request received from the UE is applicable for update of counting for a respective network slice to be used by the UE. The method further comprises sending, to a Network Function (NF) that maintains a count of a number of UEs that are using the respective network slice, a message that causes an update to the count of the number of UEs that are using the respective network slice.