Session Management for Edge Computing

A session management function (SMF) receives, from a wireless device, a packet data unit (PDU) session establishment request message requesting establishment of a PDU session associated with an application and offloaded processing of data from the wireless device to an application server associated with the application. The SMF sends, to the wireless device, a response message indicating a rejection or an acceptance of the offloaded processing of data.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Patent Application No. PCT/US2021/020247, filed 1 Mar. 2021, which claims the benefit of U.S. Provisional Application No. 62/982,507, filed 27 Feb. 2020, all of which are hereby incorporated by reference in their entireties.

DETAILED DESCRIPTION OF EXAMPLES

Example embodiments of the present invention enable implementation of enhanced features and functionalities in 4G/5G systems. Embodiments of the technology disclosed herein may be employed in the technical field of 4G/5G systems and network slicing for communication systems. More particularly, the embodiments of the technology disclosed herein may relate to 5G core network and 5G systems for network slicing in communication systems. Throughout the present disclosure, UE, wireless device, and mobile device are used interchangeably.

The following acronyms are used throughout the present disclosure:

5G5th generation mobile networks

ACK Acknowledgement

AF Application Function

AMF Access and Mobility Management Function

AN Access Network

CDR Charging Data Record

CCNF Common Control Network Functions

CN Core Network

CP Control Plane

DDN Downlink Data Notification

DL Downlink

DN Data Network

DNN Data Network Name

DRX Discontinuous Reception

gNB next generation Node B

GPSI Generic Public Subscription Identifier

GTP GPRS Tunneling Protocol

GUTI Globally Unique Temporary Identifier

HPLMN Home Public Land Mobile Network

IMSI International Mobile Subscriber Identity

LADN Local Area Data Network

LI Lawful Intercept

MEI Mobile Equipment Identifier

MICO Mobile Initiated Connection Only

MME Mobility Management Entity

MO Mobile Originated

MSISDN Mobile Subscriber ISDN

MT Mobile Terminating

NAI Network Access Identifier

NEF Network Exposure Function

NF Network Function

NGAP Next Generation Application Protocol

NR New Radio

NRF Network Repository Function

NSI Network Slice Instance

NSSAI Network Slice Selection Assistance Information

NSSF Network Slice Selection Function

OCS Online Charging System

OFCS Offline Charging System

PCF Policy Control Function

PDU Packet/Protocol Data Unit

PEI Permanent Equipment Identifier

PLMN Public Land Mobile Network

PRACH Physical Random Access CHannel

PLMN Public Land Mobile Network

PSA PDU Session Anchor

RAN Radio Access Network

QFI QoS Flow Identity

RM Registration Management

SBA Service Based Architecture

SEA Security Anchor Function

SCM Security Context Management

SI System Information

SIB System Information Block

SMF Session Management Function

SMSF SMS Function

S-NSSAI Single Network Slice Selection Assistance information

SSC Session and Service Continuity

SUCI Served User Correlation ID

SUPI Subscriber Permanent Identifier

UDM Unified Data Management

UER Unified Data Repository

UDR User Data Repository

UE User Equipment

UL Uplink

UL CL Uplink Classifier

UPF User Plane Function

VPLMN Visited Public Land Mobile Network

ExampleFIG.1andFIG.2depict a 5G system comprising of access networks and 5G core network. An example 5G access network may comprise an access network connecting to a 5G core network. An access network may comprise an NG-RAN105and/or non-3GPP AN 165. An example 5G core network may connect to one or more 5G access networks 5G-AN and/or NG-RANs. 5G core network may comprise functional elements or network functions as in exampleFIG.1and exampleFIG.2where interfaces may be employed for communication among the functional elements and/or network elements.

In an example, a network function may be a processing function in a network, which may have a functional behavior and/or interfaces. A network function may be implemented either as a network element on a dedicated hardware, and/or a network node as depicted inFIG.3andFIG.4, or as a software instance running on a dedicated hardware and/or shared hardware, or as a virtualized function instantiated on an appropriate platform.

In an example, access and mobility management function, AMF155, may include the following functionalities (some of the AMF155functionalities may be supported in a single instance of an AMF155): termination of RAN105CP interface (N1), termination of NAS (N1), NAS ciphering and integrity protection, registration management, connection management, reachability management, mobility management, lawful intercept (for AMF155events and interface to LI system), provide transport for session management, SM messages between UE100and SMF160, transparent proxy for routing SM messages, access authentication, access authorization, provide transport for SMS messages between UE100and SMSF, security anchor function, SEA, interaction with the AUSF150and the UE100, receiving the intermediate key established as a result of the UE100authentication process, security context management, SCM, that receives a key from the SEA that it uses to derive access network specific keys, and/or the like.

In an example, the AMF155may support non-3GPP access networks through N2interface with N3IWF170, NAS signaling with a UE100over N3IWF170, authentication of UEs connected over N3IWF170, management of mobility, authentication, and separate security context state(s) of a UE100connected via non-3GPP access165or connected via 3GPP access105and non-3GPP access165simultaneously, support of a coordinated RM context valid over 3GPP access105and non 3GPP access165, support of CM management contexts for the UE100for connectivity over non-3GPP access, and/or the like.

In an example, an AMF155region may comprise one or multiple AMF155sets. The AMF155set may comprise some AMF155that serve a given area and/or network slice(s). In an example, multiple AMF155sets may be per AMF155region and/or network slice(s). Application identifier may be an identifier that may be mapped to a specific application traffic detection rule. Configured NSSAI may be an NSSAI that may be provisioned in a UE100. DN115access identifier (DNAI), for a DNN, may be an identifier of a user plane access to a DN115. Initial registration may be related to a UE100registration in RM-DEREGISTERED500,520states. N2AP UE100association may be a logical per UE100association between a 5G AN node and an AMF155. N2AP UE-TNLA-binding may be a binding between a N2AP UE100association and a specific transport network layer, TNL association for a given UE100.

In an example, session management function, SMF160, may include one or more of the following functionalities (one or more of the SMF160functionalities may be supported in a single instance of a SMF160): session management (e.g. session establishment, modify and release, including tunnel maintain between UPF110and AN105node), UE100IP address allocation & management (including optional authorization), selection and control of UP function(s), configuration of traffic steering at UPF110to route traffic to proper destination, termination of interfaces towards policy control functions, control part of policy enforcement and QoS. lawful intercept (for SM events and interface to LI System), termination of SM parts of NAS messages, downlink data notification, initiation of AN specific SM information, sent via AMF155over N2to (R)AN105, determination of SSC mode of a session, roaming functionality, handling local enforcement to apply QoS SLAs (VPLMN), charging data collection and charging interface (VPLMN), lawful intercept (in VPLMN for SM events and interface to LI System), support for interaction with external DN115for transport of signaling for PDU session authorization/authentication by external DN115, and/or the like.

In an example, a user plane function, UPF110, may include one or more of the following functionalities (some of the UPF110functionalities may be supported in a single instance of a UPF110): anchor point for Intra-/Inter-RAT mobility (when applicable), external PDU session point of interconnect to DN115, packet routing & forwarding, packet inspection and user plane part of policy rule enforcement, lawful intercept (UP collection), traffic usage reporting, uplink classifier to support routing traffic flows to a data network, branching point to support multi-homed PDU session(s), QoS handling for user plane, uplink traffic verification (SDF to QoS flow mapping), transport level packet marking in the uplink and downlink, downlink packet buffering, downlink data notification triggering, and/or the like.

In an example, the UE100IP address management may include allocation and release of the UE100IP address and/or renewal of the allocated IP address. The UE100may set a requested PDU type during a PDU session establishment procedure based on its IP stack capabilities and/or configuration. In an example, the SMF160may select PDU type of a PDU session. In an example, if the SMF160receives a request with PDU type set to IP, the SMF160may select PDU type IPv4 or IPv6 based on DNN configuration and/or operator policies. In an example, the SMF160may provide a cause value to the UE100to indicate whether the other IP version is supported on the DNN. In an example, if the SMF160receives a request for PDU type IPv4 or IPv6 and the requested IP version is supported by the DNN the SMF160may select the requested PDU type.

In an example embodiment, the 5GC elements and UE100may support the following mechanisms: during a PDU session establishment procedure, the SMF160may send the IP address to the UE100via SM NAS signaling. The IPv4 address allocation and/or IPv4 parameter configuration via DHCPv4 may be employed once PDU session may be established. IPv6 prefix allocation may be supported via IPv6 stateless autoconfiguration, if IPv6 is supported. In an example, 5GC network elements may support IPv6 parameter configuration via stateless DHCPv6.

The 5GC may support the allocation of a static IPv4 address and/or a static IPv6 prefix based on subscription information in a UDM140and/or based on the configuration on a per-subscriber, per-DNN basis.

User plane function(s) (UPF110) may handle the user plane path of PDU sessions. A UPF110that provides the interface to a data network may support functionality of a PDU session anchor.

In an example, a policy control function, PCF135, may support unified policy framework to govern network behavior, provide policy rules to control plane function(s) to enforce policy rules, implement a front end to access subscription information relevant for policy decisions in a user data repository (UDR), and/or the like.

A network exposure function, NEF125, may provide means to securely expose the services and capabilities provided by the 3GPP network functions, translate between information exchanged with the AF145and information exchanged with the internal network functions, receive information from other network functions, and/or the like.

In an example, a network repository function, NRF130may support service discovery function that may receive NF discovery request from NF instance, provide information about the discovered NF instances (be discovered) to the NF instance, and maintain information about available NF instances and their supported services, and/or the like.

In an example, an NSSF120may select a set of network slice instances serving the UE100, may determine allowed NSSAI. In an example, the NSSF120may determine the AMF155set to be employed to serve the UE100, and/or, based on configuration, determine a list of candidate AMF155(s)155by querying the NRF130.

In an example, stored data in a UDR may include at least user subscription data, including at least subscription identifiers, security credentials, access and mobility related subscription data, session related subscription data, policy data, and/or the like.

In an example, an AUSF150may support authentication server function (AUSF150).

In an example, an application function (AF), AF145, may interact with the 3GPP core network to provide services. In an example, based on operator deployment, application functions may be trusted by the operator to interact directly with relevant network functions. Application functions not allowed by the operator to access directly the network functions may use an external exposure framework (e.g., via the NEF125) to interact with relevant network functions.

In an example, control plane interface between the (R)AN105and the 5G core may support connection of multiple different kinds of AN(s) (e.g. 3GPP RAN105, N3IWF170for Un-trusted access165) to the 5GC via a control plane protocol. In an example, an N2AP protocol may be employed for both the 3GPP access105and non-3GPP access165. In an example, control plane interface between the (R)AN105and the 5G core may support decoupling between AMF155and other functions such as SMF160that may need to control the services supported by AN(s) (e.g. control of the UP resources in the AN105for a PDU session).

In an example, the 5GC may provide policy information from the PCF135to the UE100. In an example, the policy information may comprise: access network discovery and selection policy, UE100route selection policy (URSP), SSC mode selection policy (SSCMSP), network slice selection policy (NSSP), DNN selection policy, non-seamless offload policy, and/or the like.

In an example, as depicted in exampleFIG.5AandFIG.5B, the registration management, RM may be employed to register or de-register a UE/user100with the network and establish the user context in the network. Connection management may be employed to establish and release the signaling connection between the UE100and the AMF155.

In an example, a UE100may register with the network to receive services that require registration. In an example, the UE100may update its registration with the network periodically in order to remain reachable (periodic registration update), or upon mobility (e.g., mobility registration update), or to update its capabilities or to re-negotiate protocol parameters.

In an example, an initial registration procedure as depicted in exampleFIG.8andFIG.9may involve execution of network access control functions (e.g. user authentication and access authorization based on subscription profiles in UDM140). ExampleFIG.9is a continuation of the initial registration procedure depicted inFIG.8. As a result of the initial registration procedure, the identity of the serving AMF155may be registered in a UDM140.

In an example, the registration management, RM procedures may be applicable over both 3GPP access105and non 3GPP access165.

An exampleFIG.5Amay depict the RM states of a UE100as observed by the UE100and AMF155. In an example embodiment, two RM states may be employed in the UE100and the AMF155that may reflect the registration status of the UE100in the selected PLMN: RM-DEREGISTERED500, and RM-REGISTERED510. In an example, in the RM DEREGISTERED state500, the UE100may not be registered with the network. The UE100context in the AMF155may not hold valid location or routing information for the UE100so the UE100may not be reachable by the AMF155. In an example, the UE100context may be stored in the UE100and the AMF155. In an example, in the RM REGISTERED state510, the UE100may be registered with the network. In the RM-REGISTERED510state, the UE100may receive services that may require registration with the network.

In an example embodiment, two RM states may be employed in AMF155for the UE100that may reflect the registration status of the UE100in the selected PLMN: RM-DEREGISTERED520, and RM-REGISTERED530.

As depicted in exampleFIG.6AandFIG.6B, connection management, CM, may comprise establishing and releasing a signaling connection between a UE100and an AMF155over N1interface. The signaling connection may be employed to enable NAS signaling exchange between the UE100and the core network. The signaling connection between the UE100and the AMF155may comprise both the AN signaling connection between the UE100and the (R)AN105(e.g. RRC connection over 3GPP access) and the N2connection for the UE100between the AN and the AMF155. In an example, the signaling connection may be a N1signaling connection. In an example, the signaling connection may be a N1NAS signaling connection.

As depicted in exampleFIG.6AandFIG.6B, two CM states may be employed for the NAS signaling connectivity of the UE100with the AMF155, CM-IDLE600,620and CM-CONNECTED610,630. A UE100in CM-IDLE600state may be in RM-REGISTERED510state and may have no NAS signaling connection established with the AMF155over N1. The UE100in CM-IDLE600state may be in RRC idle state. The UE100may perform cell selection, cell reselection, PLMN selection, and/or the like. A UE100in CM-CONNECTED610state may have a NAS signaling connection with the AMF155over N1. In an example, the UE100in CM-CONNECTED610state may be an RRC connected state. The UE100in CM-CONNECTED610state may be an RRC inactive state. In an example, a CM state in an AMF and a CM state in a UE may be different. This may be a case when a local state change happens without explicit signaling procedure (e.g., UE context release procedure) between the UE and the AMF. In an example, an RRC state in a UE (e.g., wireless device) and an RRC state in a base station (e.g., gNB, eNB) may be different. This may be a case when a local state change happens without explicit signaling procedure (e.g., RRC release procedure) between the UE and the base station.

In an example embodiment two CM states may be employed for the UE100at the AMF155, CM-IDLE620and CM-CONNECTED630.

In an example, an RRC inactive state may apply to NG-RAN (e.g. it may apply to NR and E-UTRA connected to 5G CN). The AMF155, based on network configuration, may provide assistance information to the NG RAN105, to assist the NG RAN's105decision whether the UE100may be sent to RRC inactive state. When a UE100is CM-CONNECTED610with RRC inactive state, the UE100may resume the RRC connection due to uplink data pending, mobile initiated signaling procedure, as a response to RAN105paging, to notify the network that it has left the RAN105notification area, and/or the like.

In an example, a NAS signaling connection management may include establishing and releasing a NAS signaling connection. A NAS signaling connection establishment function may be provided by the UE100and the AMF155to establish the NAS signaling connection for the UE100in CM-IDLE600state. The procedure of releasing the NAS signaling connection may be initiated by the 5G (R)AN105node or the AMF155.

In an example, reachability management of a UE100may detect whether the UE100is reachable and may provide the UE100location (e.g. access node) to the network to reach the UE100. Reachability management may be done by paging the UE100and the UE100location tracking. The UE100location tracking may include both UE100registration area tracking and UE100reachability tracking. The UE100and the AMF155may negotiate UE100reachability characteristics in CM-IDLE600,620state during registration and registration update procedures.

In an example, two UE100reachability categories may be negotiated between a UE100and an AMF155for CM-IDLE600,620state. 1) UE100reachability allowing mobile device terminated data while the UE100is CM-IDLE600mode. 2) Mobile initiated connection only (MICO) mode. The 5GC may support a PDU connectivity service that provides exchange of PDUs between the UE100and a data network identified by a DNN. The PDU connectivity service may be supported via PDU sessions that are established upon request from the UE100.

In an example, a PDU session may support one or more PDU session types. PDU sessions may be established (e.g. upon UE100request), modified (e.g. upon UE100and 5GC request) and/or released (e.g. upon UE100and 5GC request) using NAS SM signaling exchanged over N1between the UE100and the SMF160. Upon request from an application server, the 5GC may be able to trigger a specific application in the UE100. When receiving the trigger, the UE100may send it to the identified application in the UE100. The identified application in the UE100may establish a PDU session to a specific DNN.

In an example, the 5G QoS model may support a QoS flow based framework as depicted in exampleFIG.7. The 5G QoS model may support both QoS flows that require a guaranteed flow bit rate and QoS flows that may not require a guaranteed flow bit rate. In an example, the 5G QoS model may support reflective QoS. The QoS model may comprise flow mapping or packet marking at the UPF110(CN_UP)110, AN105and/or the UE100. In an example, packets may arrive from and/or destined to the application/service layer730of UE100, UPF110(CN_UP)110, and/or the AF145.

In an example, the QoS flow may be a granularity of QoS differentiation in a PDU session. A QoS flow ID, QFI, may be employed to identify the QoS flow in the 5G system. In an example, user plane traffic with the same QFI within a PDU session may receive the same traffic forwarding treatment. The QFI may be carried in an encapsulation header on N3and/or N9(e.g. without any changes to the end-to-end packet header). In an example, the QFI may be applied to PDUs with different types of payload. The QFI may be unique within a PDU session.

In an example, the QoS parameters of a QoS flow may be provided to the (R)AN105as a QoS profile over N2at PDU session establishment, QoS flow establishment, or when NG-RAN is used at every time the user plane is activated. In an example, a default QoS rule may be required for every PDU session. The SMF160may allocate the QFI for a QoS flow and may derive QoS parameters from the information provided by the PCF135. In an example, the SMF160may provide the QFI together with the QoS profile containing the QoS parameters of a QoS flow to the (R)AN105.

In an example, 5G QoS flow may be a granularity for QoS forwarding treatment in the 5G system. Traffic mapped to the same 5G QoS flow may receive the same forwarding treatment (e.g. scheduling policy, queue management policy, rate shaping policy, RLC configuration, and/or the like). In an example, providing different QoS forwarding treatment may require separate 5G QoS flows.

In an example, a 5G QoS indicator may be a scalar that may be employed as a reference to a specific QoS forwarding behavior (e.g. packet loss rate, packet delay budget) to be provided to a 5G QoS flow. In an example, the 5G QoS indicator may be implemented in the access network by the 5QI referencing node specific parameters that may control the QoS forwarding treatment (e.g. scheduling weights, admission thresholds, queue management thresholds, link layer protocol configuration, and/or the like.).

In an example, edge computing may provide compute and storage resources with adequate connectivity close to the devices generating traffic.

In an example, 5GC may support edge computing and may enable operator(s) and 3rd party services to be hosted close to the UE's access point of attachment. The 5G core network may select a UPF110close to the UE100and may execute the traffic steering from the UPF110to the local data network via a N6interface. In an example, the selection and traffic steering may be based on the UE's100subscription data, UE100location, the information from application function AF145, policy, other related traffic rules, and/or the like. In an example, the 5G core network may expose network information and capabilities to an edge computing application function. The functionality support for edge computing may include local routing where the 5G core network may select a UPF110to route the user traffic to the local data network, traffic steering where the 5G core network may select the traffic to be routed to the applications in the local data network, session and service continuity to enable UE100and application mobility, user plane selection and reselection, e.g. based on input from application function, network capability exposure where 5G core network and application function may provide information to each other via NEf125, QoS and charging where PCF135may provide rules for QoS control and charging for the traffic routed to the local data network, support of local area data network where 5G core network may provide support to connect to the LADN in a certain area where the applications are deployed, and/or the like.

An example 5G system may be a 3GPP system comprising of 5G access network105, 5G core network and a UE100, and/or the like. Allowed NSSAI may be an NSSAI provided by a serving PLMN during e.g. a registration procedure, indicating the NSSAI allowed by the network for the UE100in the serving PLMN for the current registration area.

In an example, a PDU connectivity service may provide exchange of PDUs between a UE100and a data network. A PDU session may be an association between the UE100and the data network, DN115, that may provide the PDU connectivity service. The type of association may be IP, Ethernet and/or unstructured.

Establishment of user plane connectivity to a data network via network slice instance(s) may comprise the following: performing a RM procedure to select an AMF155that supports the required network slices, and establishing one or more PDU session(s) to the required data network via the network slice instance(s).

In an example, the set of network slices for a UE100may be changed at any time while the UE100may be registered with the network, and may be initiated by the network, or the UE100.

In an example, a periodic registration update may be UE100re-registration at expiry of a periodic registration timer. A requested NSSAI may be a NSSAI that the UE100may provide to the network.

In an example, a service based interface may represent how a set of services may be provided/exposed by a given NF.

In an example, a service continuity may be an uninterrupted user experience of a service, including the cases where the IP address and/or anchoring point may change. In an example, a session continuity may refer to continuity of a PDU session. For PDU session of IP type session continuity may imply that the IP address is preserved for the lifetime of the PDU session. An uplink classifier may be a UPF110functionality that aims at diverting uplink traffic, based on filter rules provided by the SMF160, towards data network, DN115.

In an example, the 5G system architecture may support data connectivity and services enabling deployments to use techniques such as e.g. network function virtualization and/or software defined networking. The 5G system architecture may leverage service-based interactions between control plane (CP) network functions where identified. In 5G system architecture, separation of the user plane (UP) functions from the control plane functions may be considered. A 5G system may enable a network function to interact with other NF(s) directly if required.

In an example, the 5G system may reduce dependencies between the access network (AN) and the core network (CN). The architecture may comprise a converged access-agnostic core network with a common AN-CN interface which may integrate different 3GPP and non-3GPP access types.

In an example, the 5G system may support a unified authentication framework, stateless NFs, where the compute resource is decoupled from the storage resource, capability exposure, and concurrent access to local and centralized services. To support low latency services and access to local data networks, UP functions may be deployed close to the access network.

In an example, the 5G system may support roaming with home routed traffic and/or local breakout traffic in the visited PLMN. An example 5G architecture may be service-based and the interaction between network functions may be represented in two ways. (1) As service-based representation (depicted in exampleFIG.1), where network functions within the control plane, may enable other authorized network functions to access their services. This representation may also include point-to-point reference points where necessary. (2) Reference point representation, showing the interaction between the NF services in the network functions described by point-to-point reference point (e.g. N11) between any two network functions.

In an example, a network slice may comprise the core network control plane and user plane network functions, the 5G Radio Access Network; the N3IWF functions to the non-3GPP Access Network, and/or the like. Network slices may differ for supported features and network function implementation. The operator may deploy multiple network slice instances delivering the same features but for different groups of UEs, e.g. as they deliver a different committed service and/or because they may be dedicated to a customer. The NSSF120may store the mapping information between slice instance ID and NF ID (or NF address).

In an example, a UE100may simultaneously be served by one or more network slice instances via a 5G-AN. In an example, the UE 100 may be served by k network slices (e.g. k=8, 16, etc.) at a time. An AMF155instance serving the UE100logically may belong to a network slice instance serving the UE100.

In an example, a PDU session may belong to one specific network slice instance per PLMN. In an example, different network slice instances may not share a PDU session. Different slices may have slice-specific PDU sessions using the same DNN.

An S-NSSAI (Single Network Slice Selection Assistance information) may identify a network slice. An S-NSSAI may comprise a slice/service type (SST), which may refer to the expected network slice behavior in terms of features and services; and/or a slice differentiator (SD). A slice differentiator may be optional information that may complement the slice/service type(s) to allow further differentiation for selecting a network slice instance from potentially multiple network slice instances that comply with the indicated slice/service type. In an example, the same network slice instance may be selected employing different S-NSSAIs. The CN part of a network slice instance(s) serving a UE100may be selected by CN.

In an example, subscription data may include the S-NSSAI(s) of the network slices that the UE100subscribes to. One or more S-NSSAIs may be marked as default S-NSSAI. In an example, k S-NSSAI may be marked default S-NSSAI (e.g. k=8, 16, etc.). In an example, the UE100may subscribe to more than 8 S-NSSAIs.

In an example, a UE100may be configured by the HPLMN with a configured NSSAI per PLMN. Upon successful completion of a UE's registration procedure, the UE100may obtain from the AMF155an Allowed NSSAI for this PLMN, which may include one or more S-NSSAIs.

In an example, the Allowed NSSAI may take precedence over the configured NSSAI for a PLMN. The UE100may use the S-NSSAIs in the allowed NSSAI corresponding to a network slice for the subsequent network slice selection related procedures in the serving PLMN.

In an example, the establishment of user plane connectivity to a data network via a network slice instance(s) may comprise: performing a RM procedure to select an AMF155that may support the required network slices, establishing one or more PDU sessions to the required data network via the network slice instance(s), and/or the like.

In an example, when a UE100registers with a PLMN, if the UE100for the PLMN has a configured NSSAI or an allowed NSSAI, the UE100may provide to the network in RRC and NAS layer a requested NSSAI comprising the S-NSSAI(s) corresponding to the slice(s) to which the UE100attempts to register, a temporary user ID if one was assigned to the UE, and/or the like. The requested NSSAI may be configured-NSSAI, allowed-NSSAI, and/or the like.

In an example, when a UE100registers with a PLMN, if for the PLMN the UE100has no configured NSSAI or allowed NSSAI, the RAN105may route NAS signaling from/to the UE100to/from a default AMF155.

In an example, the network, based on local policies, subscription changes and/or UE100mobility, may change the set of permitted network slice(s) to which the UE100is registered. In an example, the network may perform the change during a registration procedure or trigger a notification towards the UE100of the change of the supported network slices using an RM procedure (which may trigger a registration procedure). The network may provide the UE100with a new allowed NSSAI and tracking area list.

In an example, during a registration procedure in a PLMN, in case the network decides that the UE100should be served by a different AMF155based on network slice(s) aspects, the AMF155that first received the registration request may redirect the registration request to another AMF155via the RAN105or via direct signaling between the initial AMF155and the target AMF155.

In an example, the network operator may provision the UE100with network slice selection policy (NSSP). The NSSP may comprise one or more NSSP rules.

In an example, if a UE100has one or more PDU sessions established corresponding to a specific S-NSSAI, the UE100may route the user data of the application in one of the PDU sessions, unless other conditions in the UE100may prohibit the use of the PDU sessions. If the application provides a DNN, then the UE100may consider the DNN to determine which PDU session to use. In an example, if the UE100does not have a PDU session established with the specific S-NSSAI, the UE100may request a new PDU session corresponding to the S-NSSAI and with the DNN that may be provided by the application. In an example, in order for the RAN105to select a proper resource for supporting network slicing in the RAN105, the RAN105may be aware of the network slices used by the UE100.

In an example, an AMF155may select an SMF160in a network slice instance based on S-NSSAI, DNN and/or other information e.g. UE100subscription and local operator policies, and/or the like, when the UE100triggers the establishment of a PDU session. The selected SMF160may establish the PDU session based on S-NSSAI and DNN.

In an example, in order to support network-controlled privacy of slice information for the slices the UE100may access, when the UE100is aware or configured that privacy considerations may apply to NSSAI, the UE100may not include NSSAI in NAS signaling unless the UE100has a NAS security context and the UE100may not include NSSAI in unprotected RRC signaling.

In an example, for roaming scenarios, the network slice specific network functions in VPLMN and HPLMN may be selected based on the S-NSSAI provided by the UE100during PDU connection establishment. If a standardized S-NSSAI is used, selection of slice specific NF instances may be done by each PLMN based on the provided S-NSSAI. In an example, the VPLMN may map the S-NSSAI of HPLMN to a S-NSSAI of VPLMN based on roaming agreement (e.g., including mapping to a default S-NSSAI of VPLMN). In an example, the selection of slice specific NF instance in VPLMN may be done based on the S-NSSAI of VPLMN. In an example, the selection of any slice specific NF instance in HPLMN may be based on the S-NSSAI of HPLMN.

As depicted in exampleFIG.8andFIG.9, a registration procedure may be performed by the UE100to get authorized to receive services, to enable mobility tracking, to enable reachability, and/or the like.

In an example, the UE100may send to the (R)AN105an AN message805(comprising AN parameters, RM-NAS registration request (registration type, SUCI or SUPI or 5G-GUTI, last visited TAI (if available), security parameters, requested NSSAI, mapping of requested NSSAI, UE1005GC capability, PDU session status, PDU session(s) to be re-activated, Follow on request, MICO mode preference, and/or the like), and/or the like). In an example, in case of NG-RAN, the AN parameters may include e.g. SUCI or SUPI or the 5G-GUTI, the Selected PLMN ID and requested NSSAI, and/or the like. In an example, the AN parameters may comprise establishment cause. The establishment cause may provide the reason for requesting the establishment of an RRC connection. In an example, the registration type may indicate if the UE100wants to perform an initial registration (e.g. the UE100is in RM-DEREGISTERED state), a mobility registration update (e.g., the UE100is in RM-REGISTERED state and initiates a registration procedure due to mobility), a periodic registration update (e.g., the UE100is in RM-REGISTERED state and may initiate a registration procedure due to the periodic registration update timer expiry) or an emergency registration (e.g., the UE100is in limited service state). In an example, if the UE100performing an initial registration (e.g., the UE100is in RM-DEREGISTERED state) to a PLMN for which the UE100does not already have a 5G-GUTI, the UE100may include its SUCI or SUPI in the registration request. The SUCI may be included if the home network has provisioned the public key to protect SUPI in the UE. If the UE100received a UE100configuration update command indicating that the UE100needs to re-register and the 5G-GUTI is invalid, the UE100may perform an initial registration and may include the SUPI in the registration request message. For an emergency registration, the SUPI may be included if the UE100does not have a valid 5G-GUTI available; the PEI may be included when the UE100has no SUPI and no valid 5G-GUTI. In other cases, the 5G-GUTI may be included and it may indicate the last serving AMF155. If the UE100is already registered via a non-3GPP access in a PLMN different from the new PLMN (e.g., not the registered PLMN or an equivalent PLMN of the registered PLMN) of the 3GPP access, the UE100may not provide over the 3GPP access the 5G-GUTI allocated by the AMF155during the registration procedure over the non-3GPP access. If the UE100is already registered via a 3GPP access in a PLMN (e.g., the registered PLMN), different from the new PLMN (e.g. not the registered PLMN or an equivalent PLMN of the registered PLMN) of the non-3GPP access, the UE100may not provide over the non-3GPP access the 5G-GUTI allocated by the AMF155during the registration procedure over the 3GPP access. The UE100may provide the UE's usage setting based on its configuration. In case of initial registration or mobility registration update, the UE100may include the mapping of requested NSSAI, which may be the mapping of each S-NSSAI of the requested NSSAI to the S-NSSAIs of the configured NSSAI for the HPLMN, to ensure that the network is able to verify whether the S-NSSAI(s) in the requested NSSAI are permitted based on the subscribed S-NSSAIs. If available, the last visited TAI may be included in order to help the AMF155produce registration area for the UE. In an example, the security parameters may be used for authentication and integrity protection. requested NSSAI may indicate the network slice selection assistance information. The PDU session status may indicates the previously established PDU sessions in the UE. When the UE100is connected to the two AMF155belonging to different PLMN via 3GPP access and non-3GPP access then the PDU session status may indicate the established PDU session of the current PLMN in the UE. The PDU session(s) to be re-activated may be included to indicate the PDU session(s) for which the UE100may intend to activate UP connections. A PDU session corresponding to a LADN may not be included in the PDU session(s) to be re-activated when the UE100is outside the area of availability of the LADN. The follow on request may be included when the UE100may have pending uplink signaling and the UE100may not include PDU session(s) to be re-activated, or the registration type may indicate the UE100may want to perform an emergency registration.

In an example, if a SUPI is included or the 5G-GUTI does not indicate a valid AMF155, the (R)AN105, based on (R)AT and requested NSSAI, if available, may selects808an AMF155. If UE100is in CM-CONNECTED state, the (R)AN105may forward the registration request message to the AMF155based on the N2connection of the UE. If the (R)AN105may not select an appropriate AMF155, it may forward the registration request to an AMF155which has been configured, in (R)AN105, to perform AMF155selection808.

In an example, the (R)AN105may send to the new AMF155an N2message810(comprising: N2parameters, RM-NAS registration request (registration type, SUPI or 5G-GUTI, last visited TAI (if available), security parameters, requested NSSAI, mapping of requested NSSAI, UE1005GC capability, PDU session status, PDU session(s) to be re-activated, follow on request, and MICO mode preference), and/or the like). In an example, when NG-RAN is used, the N2parameters may comprise the selected PLMN ID, location information, cell identity and the RAT type related to the cell in which the UE100is camping. In an example, when NG-RAN is used, the N2parameters may include the establishment cause.

In an example, the new AMF155may send to the old AMF155a Namf_Communication_UEContextTransfer (complete registration request)815. In an example, if the UE's 5G-GUTI was included in the registration request and the serving AMF155has changed since last registration procedure, the new AMF155may invoke the Namf_Communication_UEContextTransfer service operation815on the old AMF155including the complete registration request IE, which may be integrity protected, to request the UE's SUPI and MM Context. The old AMF155may use the integrity protected complete registration request IE to verify if the context transfer service operation invocation corresponds to the UE100requested. In an example, the old AMF155may transfer the event subscriptions information by each NF consumer, for the UE, to the new AMF155. In an example, if the UE100identifies itself with PEI, the SUPI request may be skipped.

In an example, the old AMF155may send to new AMF155a response815to Namf_Communication_UEContextTransfer (SUPI, MM context, SMF160information, PCF ID). In an example, the old AMF155may respond to the new AMF155for the Namf_Communication_UEContextTransfer invocation by including the UE's SUPI and MM context. In an example, if old AMF155holds information about established PDU sessions, the old AMF155may include SMF160information including S-NSSAI(s), SMF160identities and PDU session ID. In an example, if old AMF155holds information about active NGAP UE-TNLA bindings to N3IWF, the old AMF155may include information about the NGAP UE-TNLA bindings.

In an example, if the SUPI is not provided by the UE100nor retrieved from the old AMF155the identity request procedure820may be initiated by the AMF155sending an identity request message to the UE100requesting the SUCI.

In an example, the UE100may respond with an identity response message820including the SUCI. The UE100may derive the SUCI by using the provisioned public key of the HPLMN.

In an example, the AMF155may decide to initiate UE100authentication825by invoking an AUSF150. The AMF155may select an AUSF150based on SUPI or SUCI. In an example, if the AMF155is configured to support emergency registration for unauthenticated SUPIs and the UE100indicated registration type emergency registration the AMF155may skip the authentication and security setup or the AMF155may accept that the authentication may fail and may continue the registration procedure.

In an example, the authentication830may be performed by Nudm_UEAuthenticate_Get operation. The AUSF150may discover a UDM140. In case the AMF155provided a SUCI to AUSF150, the AUSF150may return the SUPI to AMF155after the authentication is successful. In an example, if network slicing is used, the AMF155may decide if the registration request needs to be rerouted where the initial AMF155refers to the AMF155. In an example, the AMF155may initiate NAS security functions. In an example, upon completion of NAS security function setup, the AMF155may initiate NGAP procedure to enable 5G-AN use it for securing procedures with the UE. In an example, the 5G-AN may store the security context and may acknowledge to the AMF155. The 5G-AN may use the security context to protect the messages exchanged with the UE.

In an example, new AMF155may send to the old AMF155Namf_Communication_RegistrationCompleteNotify835. If the AMF155has changed, the new AMF155may notify the old AMF155that the registration of the UE100in the new AMF155may be completed by invoking the Namf_Communication_RegistrationCompleteNotify service operation. If the authentication/security procedure fails, then the registration may be rejected, and the new AMF155may invoke the Namf_Communication_RegistrationCompleteNotify service operation with a reject indication reason code towards the old AMF155. The old AMF155may continue as if the UE100context transfer service operation was never received. If one or more of the S-NSSAIs used in the old registration area may not be served in the target registration area, the new AMF155may determine which PDU session may not be supported in the new registration area. The new AMF155may invoke the Namf_Communication_RegistrationCompleteNotify service operation including the rejected PDU session ID and a reject cause (e.g. the S-NSSAI becomes no longer available) towards the old AMF155. The new AMF155may modify the PDU session status correspondingly. The old AMF155may inform the corresponding SMF160(s) to locally release the UE's SM context by invoking the Nsmf_PDUSession_ReleaseSMContext service operation.

In an example, the new AMF155may send to the UE100an identity request/response840(e.g., PEI). If the PEI was not provided by the UE100nor retrieved from the old AMF155, the identity request procedure may be initiated by AMF155sending an identity request message to the UE100to retrieve the PEI. The PEI may be transferred encrypted unless the UE100performs emergency registration and may not be authenticated. For an emergency registration, the UE100may have included the PEI in the registration request.

In an example, the new AMF155may initiate ME identity check845by invoking the N5g-eir_Equipment_IdentityCheck_Get service operation845.

In an example, the new AMF155, based on the SUPI, may select905a UDM140. The UDM140may select a UDR instance. In an example, the AMF155may select a UDM140.

In an example, if the AMF155has changed since the last registration procedure, or if the UE100provides a SUPI which may not refer to a valid context in the AMF155, or if the UE100registers to the same AMF155it has already registered to a non-3GPP access (e.g., the UE100is registered over a non-3GPP access and may initiate the registration procedure to add a 3GPP access), the new AMF155may register with the UDM140using Nudm_UECM_Registration910and may subscribe to be notified when the UDM140may deregister the AMF155. The UDM140may store the AMF155identity associated to the access type and may not remove the AMF155identity associated to the other access type. The UDM140may store information provided at registration in UDR, by Nudr_UDM_Update. In an example, the AMF155may retrieve the access and mobility subscription data and SMF160selection subscription data using Nudm_SDM_Get915. The UDM140may retrieve this information from UDR by Nudr_UDM_Query(access and mobility subscription data). After a successful response is received, the AMF155may subscribe to be notified using Nudm_SDM_Subscribe920when the data requested may be modified. The UDM140may subscribe to UDR by Nudr_UDM_Subscribe. The GPSI may be provided to the AMF155in the subscription data from the UDM140if the GPSI is available in the UE100subscription data. In an example, the new AMF155may provide the access type it serves for the UE100to the UDM140and the access type may be set to 3GPP access. The UDM140may store the associated access type together with the serving AMF155in UDR by Nudr_UDM_Update. The new AMF155may create an MM context for the UE100after getting the mobility subscription data from the UDM140. In an example, when the UDM140stores the associated access type together with the serving AMF155, the UDM140may initiate a Nudm_UECM_DeregistrationNotification921to the old AMF155corresponding to 3GPP access. The old AMF155may remove the MM context of the UE. If the serving NF removal reason indicated by the UDM140is initial registration, then the old AMF155may invoke the Namf_EventExposure_Notify service operation towards all the associated SMF160s of the UE100to notify that the UE100is deregistered from old AMF155. The SMF160may release the PDU session(s) on getting this notification. In an example, the old AMF155may unsubscribe with the UDM140for subscription data using Nudm_SDM_unsubscribe922.

In an example, if the AMF155decides to initiate PCF135communication, e.g. the AMF155has not yet obtained access and mobility policy for the UE100or if the access and mobility policy in the AMF155are no longer valid, the AMF155may select925a PCF135. If the new AMF155receives a PCF ID from the old AMF155and successfully contacts the PCF135identified by the PCF ID, the AMF155may select the (V-)PCF identified by the PCF ID. If the PCF135identified by the PCF ID may not be used (e.g. no response from the PCF135) or if there is no PCF ID received from the old AMF155, the AMF155may select925a PCF135.

In an example, the new AMF155may perform a policy association establishment930during registration procedure. If the new AMF155contacts the PCF135identified by the (V-)PCF ID received during inter-AMF155mobility, the new AMF155may include the PCF-ID in the Npcf_AMPolicyControl Get operation. If the AMF155notifies the mobility restrictions (e.g. UE100location) to the PCF135for adjustment, or if the PCF135updates the mobility restrictions itself due to some conditions (e.g. application in use, time and date), the PCF135may provide the updated mobility restrictions to the AMF155.

In an example, the AMF155may send to the SMF160an Nsmf_PDUSession_UpdateSMContext936. In an example, the AMF155may invoke the Nsmf_PDUSession_UpdateSMContext if the PDU session(s) to be re-activated is included in the registration request. The AMF155may send Nsmf_PDUSession_UpdateSMContext request to SMF160(s) associated with the PDU session(s) to activate user plane connections of the PDU session(s). The SMF160may decide to trigger e.g. the intermediate UPF110insertion, removal or change of PSA. In the case that the intermediate UPF110insertion, removal, or relocation is performed for the PDU session(s) not included in PDU session(s) to be re-activated, the procedure may be performed without N11and N2interactions to update the N3user plane between (R)AN105and SGC. The AMF155may invoke the Nsmf_PDUSession_ReleaseSMContext service operation towards the SMF160if any PDU session status indicates that it is released at the UE100. The AMF155may invoke the Nsmf_PDUSession_ReleaseSMContext service operation towards the SMF160in order to release any network resources related to the PDU session.

In an example, the new AMF155may send to a N3IWF an N2AMF155mobility request940. If the AMF155has changed, the new AMF155may create an NGAP UE100association towards the N3IWF to which the UE100is connected. In an example, the N3IWF may respond to the new AMF155with an N2AMF155mobility response940.

In an example, the new AMF155may send to the UE100a registration accept955(comprising: 5G-GUTI, registration area, mobility restrictions, PDU session status, allowed NSSAI, [mapping of allowed NSSAI], periodic registration update timer, LADN information and accepted MICO mode, IMS voice over PS session supported indication, emergency service support indicator, and/or the like). In an example, the AMF155may send the registration accept message to the UE100indicating that the registration request has been accepted. 5G-GUTI may be included if the AMF155allocates a new 5G-GUTI. If the AMF155allocates a new registration area, it may send the registration area to the UE100via registration accept message955. If there is no registration area included in the registration accept message, the UE100may consider the old registration area as valid. In an example, mobility restrictions may be included in case mobility restrictions may apply for the UE100and registration type may not be emergency registration. The AMF155may indicate the established PDU sessions to the UE100in the PDU session status. The UE100may remove locally any internal resources related to PDU sessions that are not marked as established in the received PDU session status. In an example, when the UE100is connected to the two AMF155belonging to different PLMN via 3GPP access and non-3GPP access then the UE100may remove locally any internal resources related to the PDU session of the current PLMN that are not marked as established in received PDU session status. If the PDU session status information was in the registration request, the AMF155may indicate the PDU session status to the UE. The mapping of allowed NSSAI may be the mapping of each S-NSSAI of the allowed NSSAI to the S-NSSAIs of the configured NSSAI for the HPLMN. The AMF155may include in the registration accept message955the LADN information for LADNs that are available within the registration area determined by the AMF155for the UE. If the UE100included MICO mode in the request, then AMF155may respond whether MICO mode may be used. The AMF155may set the IMS voice over PS session supported Indication. In an example, in order to set the IMS voice over PS session supported indication, the AMF155may perform a UE/RAN radio information and compatibility request procedure to check the compatibility of the UE100and RAN radio capabilities related to IMS voice over PS. In an example, the emergency service support indicator may inform the UE100that emergency services are supported, e.g., the UE100may request PDU session for emergency services. In an example, the handover restriction list and UE-AMBR may be provided to NG-RAN by the AMF155.

In an example, the UE100may send to the new AMF155a registration complete960message. In an example, the UE100may send the registration complete message960to the AMF155to acknowledge that a new 5G-GUTI may be assigned. In an example, when information about the PDU session(s) to be re-activated is not included in the registration request, the AMF155may release the signaling connection with the UE100. In an example, when the follow-on request is included in the registration request, the AMF155may not release the signaling connection after the completion of the registration procedure. In an example, if the AMF155is aware that some signaling is pending in the AMF155or between the UE100and the SGC, the AMF155may not release the signaling connection after the completion of the registration procedure.

As depicted in exampleFIG.10andFIG.11, a service request procedure e.g., a UE100triggered service request procedure may be used by a UE100in CM-IDLE state to request the establishment of a secure connection to an AMF155.FIG.11is continuation ofFIG.10depicting the service request procedure. The service request procedure may be used to activate a user plane connection for an established PDU session. The service request procedure may be triggered by the UE100or the SGC, and may be used when the UE100is in CM-IDLE and/or in CM-CONNECTED and may allow selectively to activate user plane connections for some of the established PDU sessions.

In an example, a UE100in CM IDLE state may initiate the service request procedure to send uplink signaling messages, user data, and/or the like, as a response to a network paging request, and/or the like. In an example, after receiving the service request message, the AMF155may perform authentication. In an example, after the establishment of signaling connection to the AMF155, the UE100or network may send signaling messages, e.g. PDU session establishment from the UE100to a SMF160, via the AMF155.

In an example, for any service request, the AMF155may respond with a service accept message to synchronize PDU session status between the UE100and network. The AMF155may respond with a service reject message to the UE100, if the service request may not be accepted by the network. The service reject message may include an indication or cause code requesting the UE100to perform a registration update procedure. In an example, for service request due to user data, network may take further actions if user plane connection activation may not be successful. In an exampleFIG.10andFIG.11, more than one UPF, e.g., old UPF110-2and PDU session Anchor PSA UPF110-3may be involved.

In an example, the UE100may send to a (R)AN105an AN message comprising AN parameters, mobility management, MM NAS service request1005(e.g., list of PDU sessions to be activated, list of allowed PDU sessions, security parameters, PDU session status, and/or the like), and/or the like. In an example, the UE100may provide the list of PDU sessions to be activated when the UE100may re-activate the PDU session(s). The list of allowed PDU sessions may be provided by the UE100when the service request may be a response of a paging or a NAS notification, and may identify the PDU sessions that may be transferred or associated to the access on which the service request may be sent. In an example, for the case of NG-RAN, the AN parameters may include selected PLMN ID, and an establishment cause. The establishment cause may provide the reason for requesting the establishment of an RRC connection. The UE100may send NAS service request message towards the AMF155encapsulated in an RRC message to the RAN105.

In an example, if the service request may be triggered for user data, the UE100may identify, using the list of PDU sessions to be activated, the PDU session(s) for which the UP connections are to be activated in the NAS service request message. If the service request may be triggered for signaling, the UE100may not identify any PDU session(s). If this procedure may be triggered for paging response, and/or the UE100may have at the same time user data to be transferred, the UE100may identify the PDU session(s) whose UP connections may be activated in MM NAS service request message, by the list of PDU sessions to be activated.

In an example, if the service request over 3GPP access may be triggered in response to a paging indicating non-3GPP access, the NAS service request message may identify in the list of allowed PDU sessions the list of PDU sessions associated with the non-3GPP access that may be re-activated over 3GPP. In an example, the PDU session status may indicate the PDU sessions available in the UE100. In an example, the UE100may not trigger the service request procedure for a PDU session corresponding to a LADN when the UE100may be outside the area of availability of the LADN. The UE100may not identify such PDU session(s) in the list of PDU sessions to be activated, if the service request may be triggered for other reasons.

In an example, the (R)AN105may send to AMF155an N2Message1010(e.g., a service request) comprising N2parameters, MM NAS service request, and/or the like. The AMF155may reject the N2message if it may not be able to handle the service request. In an example, if NG-RAN may be used, the N2parameters may include the 5G-GUTI, selected PLMN ID, location information, RAT type, establishment cause, and/or the like. In an example, the 5G-GUTI may be obtained in RRC procedure and the (R)AN105may select the AMF155according to the 5G-GUTI. In an example, the location information and RAT type may relate to the cell in which the UE100may be camping. In an example, based on the PDU session status, the AMF155may initiate PDU session release procedure in the network for the PDU sessions whose PDU session ID(s) may be indicated by the UE100as not available.

In an example, if the service request was not sent integrity protected or integrity protection verification failed, the AMF155may initiate a NAS authentication/security procedure1015.

In an example, if the UE100triggers the service request to establish a signaling connection, upon successful establishment of the signaling connection, the UE100and the network may exchange NAS signaling.

In an example the AMF155may send to the SMF160a PDU session update context request1020e.g., Nsmf_PDUSession_UpdateSMContext request comprising PDU session ID(s), Cause(s), UE100location information, access type, and/or the like.

In an example, the Nsmf_PDUSession_UpdateSMContext request may be invoked by the AMF155if the UE100may identify PDU session(s) to be activated in the NAS service request message. In an example, the Nsmf_PDUSession_UpdateSMContext request may be triggered by the SMF160wherein the PDU session(s) identified by the UE100may correlate to other PDU session ID(s) than the one triggering the procedure. In an example, the Nsmf_PDUSession_UpdateSMContext request may be triggered by the SMF160wherein the current UE100location may be outside the area of validity for the N2information provided by the SMF160during a network triggered service request procedure. The AMF155may not send the N2information provided by the SMF160during the network triggered service request procedure.

In an example, the AMF155may determine the PDU session(s) to be activated and may send a Nsmf_PDUSession_UpdateSMContext request to SMF160(s) associated with the PDU session(s) with cause set to indicate establishment of user plane resources for the PDU session(s).

In an example, if the procedure may be triggered in response to paging indicating non-3GPP access, and the list of allowed PDU sessions provided by the UE100may not include the PDU session for which the UE100was paged, the AMF155may notify the SMF160that the user plane for the PDU session may not be re-activated. The service request procedure may succeed without re-activating the user plane of any PDU sessions, and the AMF155may notify the UE100.

In an example, if the PDU session ID may correspond to a LADN and the SMF160may determine that the UE100may be outside the area of availability of the LADN based on the UE100location reporting from the AMF155, the SMF160may decide to (based on local policies) keep the PDU session, may reject the activation of user plane connection for the PDU session and may inform the AMF155. In an example, if the procedure may be triggered by a network triggered service request, the SMF160may notify the UPF110that originated the data notification to discard downlink data for the PDU sessions and/or to not provide further data notification messages. The SMF160may respond to the AMF155with an appropriate reject cause and the user plane activation of PDU session may be stopped.

In an example, if the PDU session ID may correspond to a LADN and the SMF160may determine that the UE100may be outside the area of availability of the LADN based on the UE100location reporting from the AMF155, the SMF160may decide to (based on local policies) release the PDU session. The SMF160may locally release the PDU session and may inform the AMF155that the PDU session may be released. The SMF160may respond to the AMF155with an appropriate reject cause and the user plane Activation of PDU session may be stopped.

In an example, if the UP activation of the PDU session may be accepted by the SMF160, based on the location info received from the AMF155, the SMF160may check the UPF110Selection1025Criteria (e.g., slice isolation requirements, slice coexistence requirements, UPF's110dynamic load, UPF's110relative static capacity among UPFs supporting the same DNN, UPF110location available at the SMF160, UE100location information, Capability of the UPF110and the functionality required for the particular UE100session. In an example, an appropriate UPF110may be selected by matching the functionality and features required for a UE100, DNN, PDU session type (e.g. IPv4, IPv6, ethernet type or unstructured type) and if applicable, the static IP address/prefix, SSC mode selected for the PDU session, UE100subscription profile in UDM140, DNAI as included in the PCC rules, local operator policies, S-NSSAI, access technology being used by the UE100, UPF110logical topology, and/or the like), and may determine to perform one or more of the following: continue using the current UPF(s); may select a new intermediate UPF110(or add/remove an intermediate UPF110), if the UE100has moved out of the service area of the UPF110that was previously connecting to the (R)AN105, while maintaining the UPF(s) acting as PDU session anchor; may trigger re-establishment of the PDU session to perform relocation/reallocation of the UPF110acting as PDU session anchor, e.g. the UE100has moved out of the service area of the anchor UPF110which is connecting to RAN105.

In an example, the SMF160may send to the UPF110(e.g., new intermediate UPF110) an N4session establishment request1030. In an example, if the SMF160may select a new UPF110to act as intermediate UPF110-2for the PDU session, or if the SMF160may select to insert an intermediate UPF110for a PDU session which may not have an intermediate UPF110-2, an N4session establishment request1030message may be sent to the new UPF110, providing packet detection, data forwarding, enforcement and reporting rules to be installed on the new intermediate UPF. The PDU session anchor addressing information (on N9) for this PDU session may be provided to the intermediate UPF110-2.

In an example, if a new UPF110is selected by the SMF160to replace the old (intermediate) UPF110-2, the SMF160may include a data forwarding indication. The data forwarding indication may indicate to the UPF110that a second tunnel endpoint may be reserved for buffered DL data from the old I-UPF.

In an example, the new UPF110(intermediate) may send to SMF160an N4session establishment response message1030. In case the UPF110may allocate CN tunnel info, the UPF110may provide DL CN tunnel info for the UPF110acting as PDU session anchor and UL CN tunnel info (e.g., CN N3tunnel info) to the SMF160. If the data forwarding indication may be received, the new (intermediate) UPF110acting as N3terminating point may send DL CN tunnel info for the old (intermediate) UPF110-2to the SMF160. The SMF160may start a timer, to release the resource in the old intermediate UPF110-2.

In an example, if the SMF160may selects a new intermediate UPF110for the PDU session or may remove the old I-UPF110-2, the SMF160may send N4session modification request message1035to PDU session anchor, PSA UPF110-3, providing the data forwarding indication and DL tunnel information from new intermediate UPF110.

In an example, if the new intermediate UPF110may be added for the PDU session, the (PSA) UPF110-3may begin to send the DL data to the new I-UPF110as indicated in the DL tunnel information.

In an example, if the service request may be triggered by the network, and the SMF160may remove the old I-UPF110-2and may not replace the old I-UPF110-2with the new I-UPF110, the SMF160may include the data forwarding indication in the request. The data forwarding indication may indicate to the (PSA) UPF110-3that a second tunnel endpoint may be reserved for buffered DL data from the old I-UPF110-2. In this case, the PSA UPF110-3may begin to buffer the DL data it may receive at the same time from the N6interface.

In an example, the PSA UPF110-3(PSA) may send to the SMF160an N4session modification response1035. In an example, if the data forwarding indication may be received, the PSA UPF110-3may become as N3terminating point and may send CN DL tunnel info for the old (intermediate) UPF110-2to the SMF160. The SMF160may start a timer, to release the resource in old intermediate UPF110-2if there is one.

In an example, the SMF160may send to the old UPF110-2an N4session modification request1045(e.g., may comprise new UPF110address, new UPF110DL tunnel ID, and/or the like). In an example, if the service request may be triggered by the network, and/or the SMF160may remove the old (intermediate) UPF110-2, the SMF160may send the N4session modification request message to the old (intermediate) UPF110-2, and may provide the DL tunnel information for the buffered DL data. If the SMF160may allocate new I-UPF110, the DL tunnel information is from the new (intermediate) UPF110may act as N3terminating point. If the SMF160may not allocate a new I-UPF110, the DL tunnel information may be from the new UPF110(PSA)110-3acting as N3terminating point. The SMF160may start a timer to monitor the forwarding tunnel. In an example, the old (intermediate) UPF110-2may send N4session modification response message to the SMF160.

In an example, if the I-UPF110-2may be relocated and forwarding tunnel was established to the new I-UPF110, the old (intermediate) UPF110-2may forward its buffered data to the new (intermediate) UPF110acting as N3terminating point. In an example, if the old I-UPF110-2may be removed and the new I-UPF110may not be assigned for the PDU session and forwarding tunnel may be established to the UPF110(PSA)110-3, the old (intermediate) UPF110-2may forward its buffered data to the UPF110(PSA)110-3acting as N3terminating point.

In an example, the SMF160may send to the AMF155an N11message1060e.g., a Nsmf_PDUSession_UpdateSMContext response (comprising: N1SM container (PDU session ID, PDU session re-establishment indication), N2SM information (PDU session ID, QoS profile, CN N3tunnel info, S-NSSAI), Cause), upon reception of the Nsmf_PDUSession_UpdateSMContext request with a cause including e.g., establishment of user plane resources. The SMF160may determine whether UPF110reallocation may be performed, based on the UE100location information, UPF110service area and operator policies. In an example, for a PDU session that the SMF160may determine to be served by the current UPF110, e.g., PDU session anchor or intermediate UPF, the SMF160may generate N2SM information and may send a Nsmf_PDUSession_UpdateSMContext response1060to the AMF155to establish the user plane(s). The N2SM information may contain information that the AMF155may provide to the RAN105. In an example, for a PDU session that the SMF160may determine as requiring a UPF110relocation for PDU session anchor UPF, the SMF160may reject the activation of UP of the PDU session by sending Nsmf_PDUSession_UpdateSMContext response that may contain N1SM container to the UE100via the AMF155. The N1SM container may include the corresponding PDU session ID and PDU session re-establishment indication.

Upon reception of the Namf_EventExposure_Notify from the AMF155to the SMF160, with an indication that the UE100is reachable, if the SMF160may have pending DL data, the SMF160may invoke the Namf_Communication_N1N2MessageTransfer service operation to the AMF155to establish the user plane(s) for the PDU sessions. In an example, the SMF160may resume sending DL data notifications to the AMF155in case of DL data.

In an example, the SMF160may send a message to the AMF155to reject the activation of UP of the PDU session by including a cause in the Nsmf_PDUSession_UpdateSMContext response if the PDU session may correspond to a LADN and the UE100may be outside the area of availability of the LADN, or if the AMF155may notify the SMF160that the UE100may be reachable for regulatory prioritized service, and the PDU session to be activated may not for a regulatory prioritized service; or if the SMF160may decide to perform PSA UPF110-3relocation for the requested PDU session.

In an example, the AMF155may send to the (R)AN105an N2request message1065(e.g., N2SM information received from SMF160, security context, AMF155signaling connection ID, handover restriction list, MM NAS service accept, list of recommended cells/TAs/NG-RAN node identifiers). In an example, the RAN105may store the security context, AMF155signaling connection Id, QoS information for the QoS flows of the PDU sessions that may be activated and N3tunnel IDs in the UE100RAN105context. In an example, the MM NAS service accept may include PDU session status in the AMF155. If the activation of UP of a PDU session may be rejected by the SMF160, the MM NAS service accept may include the PDU session ID and the reason why the user plane resources may not be activated (e.g. LADN not available). Local PDU session release during the session request procedure may be indicated to the UE100via the session Status.

In an example, if there are multiple PDU sessions that may involve multiple SMF160s, the AMF155may not wait for responses from all SMF160s before it may send N2SM information to the UE100. The AMF155may wait for all responses from the SMF160s before it may send MM NAS service accept message to the UE100.

In an example, the AMF155may include at least one N2SM information from the SMF160if the procedure may be triggered for PDU session user plane activation. AMF155may send additional N2SM information from SMF160s in separate N2message(s) (e.g. N2tunnel setup request), if there is any. Alternatively, if multiple SMF160s may be involved, the AMF155may send one N2request message to (R)AN105after all the Nsmf_PDUSession_UpdateSMContext response service operations from all the SMF160s associated with the UE100may be received. In such case, the N2request message may include the N2SM information received in each of the Nsmf_PDUSession_UpdateSMContext response and PDU session ID to enable AMF155to associate responses to relevant SMF160.

In an example, if the RAN105(e.g., NG RAN) node may provide the list of recommended cells/TAs/NG-RAN node identifiers during the AN release procedure, the AMF155may include the information from the list in the N2request. The RAN105may use this information to allocate the RAN105notification area when the RAN105may decide to enable RRC inactive state for the UE100.

If the AMF155may receive an indication, from the SMF160during a PDU session establishment procedure that the UE100may be using a PDU session related to latency sensitive services, for any of the PDU sessions established for the UE100and the AMF155has received an indication from the UE100that may support the CM-CONNECTED with RRC inactive state, then the AMF155may include the UE's RRC inactive assistance information. In an example, the AMF155based on network configuration, may include the UE's RRC inactive assistance information.

In an example, the (R)AN105may send to the UE100a message to perform RRC connection reconfiguration1070with the UE100depending on the QoS information for all the QoS flows of the PDU sessions whose UP connections may be activated and data radio bearers. In an example, the user plane security may be established.

In an example, if the N2request may include a MM NAS service accept message, the RAN105may forward the MM NAS service accept to the UE100. The UE100may locally delete context of PDU sessions that may not be available in SGC.

In an example, if the N1SM information may be transmitted to the UE100and may indicate that some PDU session(s) may be re-established, the UE100may initiate PDU session re-establishment for the PDU session(s) that may be re-established after the service request procedure may be complete.

In an example, after the user plane radio resources may be setup, the uplink data from the UE100may be forwarded to the RAN105. The RAN105(e.g., NG-RAN) may send the uplink data to the UPF110address and tunnel ID provided.

In an example, the (R)AN105may send to the AMF155an N2request Ack1105(e.g., N2SM information (comprising: AN tunnel info, list of accepted QoS flows for the PDU sessions whose UP connections are activated, list of rejected QoS flows for the PDU sessions whose UP connections are activated)). In an example, the N2request message may include N2SM information(s), e.g. AN tunnel info. RAN105may respond N2SM information with separate N2message (e.g. N2tunnel setup response). In an example, if multiple N2SM information are included in the N2request message, the N2request Ack may include multiple N2SM information and information to enable the AMF155to associate the responses to relevant SMF160.

In an example, the AMF155may send to the SMF160a Nsmf_PDUSession_UpdateSMContext request1110(N2SM information (AN tunnel info), RAT type) per PDU session. If the AMF155may receive N2SM information (one or multiple) from the RAN105, then the AMF155may forward the N2SM information to the relevant SMF160. If the UE100time zone may change compared to the last reported UE100Time Zone then the AMF155may include the UE100time zone IE in the Nsmf_PDUSession_UpdateSMContext request message.

In an example, if dynamic PCC is deployed, the SMF160may initiate notification about new location information to the PCF135(if subscribed) by invoking an event exposure notification operation (e.g., a Nsmf_EventExposure_Notify service operation). The PCF135may provide updated policies by invoking a policy control update notification message1115(e.g., a Npcf_SMPolicyControl_UpdateNotify operation).

In an example, if the SMF160may select a new UPF110to act as intermediate UPF110for the PDU session, the SMF160may initiates an N4session modification procedure1120to the new I-UPF110and may provide AN tunnel info. The downlink data from the new I-UPF110may be forwarded to RAN105and UE100. In an example, the UPF110may send to the SMF160, an N4session modification response1120. In an example, the SMF160may send to the AMF155, a Nsmf_PDUSession_UpdateSMContext response1140.

In an example, if forwarding tunnel may be established to the new I-UPF110and if the timer SMF160set for forwarding tunnel may be expired, the SMF160may sends N4session modification request1145to new (intermediate) UPF110acting as N3terminating point to release the forwarding tunnel. In an example, the new (intermediate) UPF110may send to the SMF160an N4session modification response1145. In an example, the SMF160may send to the PSA UPF110-3an N4session modification request1150, or N4session release request. In an example, if the SMF160may continue using the old UPF110-2, the SMF160may send an N4session modification request1155, providing AN tunnel info. In an example, if the SMF160may select a new UPF110to act as intermediate UPF110, and the old UPF110-2may not be PSA UPF110-3, the SMF160may initiate resource release, after timer expires, by sending an N4session release request (release cause) to the old intermediate UPF110-2.

In an example, the old intermediate UPF110-2may send to the SMF160an N4session modification response or N4session release response1155. The old UPF110-2may acknowledge with the N4session modification response or N4session release response message to confirm the modification or release of resources. The AMF155may invoke the Namf_EventExposure_Notify service operation to notify the mobility related events, after this procedure may complete, towards the NFs that may have subscribed for the events. In an example, the AMF155may invoke the Namf_EventExposure_Notify towards the SMF160if the SMF160had subscribed for UE100moving into or out of area of interest and if the UE's current location may indicate that it may be moving into or moving outside of the area of interest subscribed, or if the SMF160had subscribed for LADN DNN and if the UE100may be moving into or outside of an area where the LADN is available, or if the UE100may be in MICO mode and the AMF155had notified an SMF160of the UE100being unreachable and that SMF160may not send DL data notifications to the AMF155, and the AMF155may informs the SMF160that the UE100is reachable, or if the SMF160had subscribed for UE100reachability status, then the AMF155may notify the UE100reachability.

An example PDU session establishment procedure depicted inFIG.12andFIG.13. In an example embodiment, when the PDU session establishment procedure may be employed, the UE100may send to the AMF155a NAS Message1205(or a SM NAS message) comprising NSSAI, S-NSSAI (e.g., requested S-NSSAI, allowed S-NSSAI, subscribed S-NSSAI, and/or the like), DNN, PDU session ID, request type, old PDU session ID, N1SM container (PDU session establishment request), and/or the like. In an example, the UE100, in order to establish a new PDU session, may generate a new PDU session ID. In an example, when emergency service may be required and an emergency PDU session may not already be established, the UE100may initiate the UE100requested PDU session establishment procedure with a request type indicating emergency request. In an example, the UE100may initiate the UE100requested PDU session establishment procedure by the transmission of the NAS message containing a PDU session establishment request within the N1SM container. The PDU session establishment request may include a PDU type, SSC mode, protocol configuration options, and/or the like. In an example, the request type may indicate initial request if the PDU session establishment is a request to establish the new PDU session and may indicate existing PDU session if the request refers to an existing PDU session between 3GPP access and non-3GPP access or to an existing PDN connection in EPC. In an example, the request type may indicate emergency request if the PDU session establishment may be a request to establish a PDU session for emergency services. The request type may indicate existing emergency PDU session if the request refers to an existing PDU session for emergency services between 3GPP access and non-3GPP access. In an example, the NAS message sent by the UE100may be encapsulated by the AN in a N2message towards the AMF155that may include user location information and access technology type information. In an example, the PDU session establishment request message may contain SM PDU DN request container containing information for the PDU session authorization by the external DN. In an example, if the procedure may be triggered for SSC mode 3 operation, the UE100may include the old PDU session ID which may indicate the PDU session ID of the on-going PDU session to be released, in the NAS message. The old PDU session ID may be an optional parameter which may be included in this case. In an example, the AMF155may receive from the AN the NAS message (e.g., NAS SM message) together with user location information (e.g. cell ID in case of the RAN105). In an example, the UE100may not trigger a PDU session establishment for a PDU session corresponding to a LADN when the UE100is outside the area of availability of the LADN.

In an example, the AMF155may determine that the NAS message or the SM NAS message may correspond to the request for the new PDU session based on that request type indicates initial request and that the PDU session ID may not be used for any existing PDU session(s) of the UE100. If the NAS message does not contain an S-NSSAI, the AMF155may determine a default S-NSSAI for the requested PDU session either according to the UE100subscription, if it may contain only one default S-NSSAI, or based on operator policy. In an example, the AMF155may perform SMF160selection1210and select an SMF160. If the request type may indicate initial request or the request may be due to handover from EPS, the AMF155may store an association of the S-NSSAI, the PDU session ID and a SMF160ID. In an example, if the request type is initial request and if the old PDU session ID indicating the existing PDU session may be contained in the message, the AMF155may select the SMF160and may store an association of the new PDU session ID and the selected SMF160ID.

In an example, the AMF155may send to the SMF160, an N11message1215, e.g., Nsmf_PDUSession_CreateSMContext request (comprising: SUPI or PEI, DNN, S-NSSAI, PDU session ID, AMF155ID, request type, N1SM container (PDU session establishment request), user location information, access type, PEI, GPSI), or Nsmf_PDUSession_UpdateSMContext request (SUPI, DNN, S-NSSAI, PDU session ID, AMF155ID, request type, N1SM container (PDU session establishment request), user location information, access type, RAT type, PEI). In an example, if the AMF155may not have an association with the SMF160for the PDU session ID provided by the UE100(e.g. when request type indicates initial request), the AMF155may invoke the Nsmf_PDUSession_CreateSMContext request, but if the AMF155already has an association with an SMF160for the PDU session ID provided by the UE100(e.g. when request type indicates existing PDU session), the AMF155may invoke the Nsmf_PDUSession_UpdateSMContext request. In an example, the AMF155ID may be the UE's GUAMI which uniquely identifies the AMF155serving the UE100. The AMF155may forward the PDU session ID together with the N1SM container containing the PDU session establishment request received from the UE100. The AMF155may provide the PEI instead of the SUPI when the UE100has registered for emergency services without providing the SUPI. In case the UE100has registered for emergency services but has not been authenticated, the AMF155may indicate that the SUPI has not been authenticated.

In an example, if the request type may indicate neither emergency request nor existing emergency PDU session and, if the SMF160has not yet registered and subscription data may not be available, the SMF160may register with the UDM140, and may retrieve subscription data1225and subscribes to be notified when subscription data may be modified. In an example, if the request type may indicate existing PDU session or existing emergency PDU session, the SMF160may determine that the request may be due to handover between 3GPP access and non-3GPP access or due to handover from EPS. The SMF160may identify the existing PDU session based on the PDU session ID. The SMF160may not create a new SM context but instead may update the existing SM context and may provide the representation of the updated SM context to the AMF155in the response. if the request type may be initial request and if the old PDU session ID may be included in Nsmf_PDUSession_CreateSMContext request, the SMF160may identify the existing PDU session to be released based on the old PDU session ID.

In an example, the SMF160may send to the AMF155, the N11message response1220, e.g., either a PDU session create/update response, Nsmf_PDUSession_CreateSMContext response1220(cause, SM context ID or N1SM container (PDU session reject(cause))) or a Nsmf_PDUSession_UpdateSMContext response.

In an example, if the SMF160may perform secondary authorization/authentication1230during the establishment of the PDU session by a DN-AAA server, the SMF160may select a UPF110and may trigger a PDU session establishment authentication/authorization.

In an example, if the request type may indicate initial request, the SMF160may select an SSC mode for the PDU session. The SMF160may select one or more UPFs as needed. In case of PDU type IPv4 or IPv6, the SMF160may allocate an IP address/prefix for the PDU session. In case of PDU type IPv6, the SMF160may allocate an interface identifier to the UE100for the UE100to build its link-local address. For Unstructured PDU type the SMF160may allocate an IPv6 prefix for the PDU session and N6point-to-point tunneling (based on UDP/IPv6).

In an example, if dynamic PCC is deployed, the may SMF160performs PCF135selection1235. If the request type indicates existing PDU session or existing emergency PDU session, the SMF160may use the PCF135already selected for the PDU session. If dynamic PCC is not deployed, the SMF160may apply local policy.

In an example, the SMF160may perform a session management policy establishment procedure1240to establish a PDU session with the PCF135and may get the default PCC Rules for the PDU session. The GPSI may be included if available at the SMF160. If the request type in1215indicates existing PDU session, the SMF160may notify an event previously subscribed by the PCF135by a session management policy modification procedure and the PCF135may update policy information in the SMF160. The PCF135may provide authorized session-AMBR and the authorized 5QI and ARP to SMF160. The PCF135may subscribe to the IP allocation/release event in the SMF160(and may subscribe other events).

In an example, the PCF135, based on the emergency DNN, may set the ARP of the PCC rules to a value that may be reserved for emergency services.

In an example, if the request type in1215indicates initial request, the SMF160may select an SSC mode for the PDU session. The SMF160may select1245one or more UPFs as needed. In case of PDU type IPv4 or IPv6, the SMF160may allocate an IP address/prefix for the PDU session. In case of PDU type IPv6, the SMF160may allocate an interface identifier to the UE100for the UE100to build its link-local address. For unstructured PDU type the SMF160may allocate an IPv6 prefix for the PDU session and N6point-to-point tunneling (e.g., based on UDP/IPv6). In an example, for Ethernet PDU type PDU session, neither a MAC nor an IP address may be allocated by the SMF160to the UE100for this PDU session.

In an example, if the request type in1215is existing PDU session, the SMF160may maintain the same IP address/prefix that may be allocated to the UE100in the source network.

In an example, if the request type in1215indicates existing PDU session referring to an existing PDU session moved between 3GPP access and non-3GPP access, the SMF160may maintain the SSC mode of the PDU session, e.g., the current PDU session Anchor and IP address. In an example, the SMF160may trigger e.g. new intermediate UPF110insertion or allocation of a new UPF110. In an example, if the request type indicates emergency request, the SMF160may select1245the UPF110and may select SSC mode 1.

In an example, the SMF160may perform a session management policy modification1250procedure to report some event to the PCF135that has previously subscribed. If request type is initial request and dynamic PCC is deployed and PDU type is IPv4 or IPv6, the SMF160may notify the PCF135(that has previously subscribed) with the allocated UE100IP address/prefix.

In an example, the PCF135may provide updated policies to the SMF160. The PCF135may provide authorized session-AMBR and the authorized 5QI and ARP to the SMF160.

In an example, if request type indicates initial request, the SMF160may initiate an N4session establishment procedure1255with the selected UPF110. The SMF160may initiate an N4session modification procedure with the selected UPF110. In an example, the SMF160may send an N4session establishment/modification request1255to the UPF110and may provide packet detection, enforcement, reporting rules, and/or the like to be installed on the UPF110for this PDU session. If CN tunnel info is allocated by the SMF160, the CN tunnel info may be provided to the UPF110. If the selective user plane deactivation is required for this PDU session, the SMF160may determine the Inactivity Timer and may provide it to the UPF110. In an example, the UPF110may acknowledges by sending an N4session establishment/modification response1255. If CN tunnel info is allocated by the UPF, the CN tunnel info may be provided to SMF160. In an example, if multiple UPFs are selected for the PDU session, the SMF160may initiate N4session establishment/modification procedure1255with each UPF110of the PDU session.

In an example, the SMF160may send to the AMF155an Namf_Communication_N1N2MessageTransfer1305message (comprising PDU session ID, access type, N2SM information (PDU session ID, QFI(s), QoS profile(s), CN tunnel info, S-NSSAI, session-AMBR, PDU session type, and/or the like), N1SM container (PDU session establishment accept (QoS Rule(s), selected SSC mode, S-NSSAI, allocated IPv4 address, interface identifier, session-AMBR, selected PDU session type, and/or the like))). In case of multiple UPFs are used for the PDU session, the CN tunnel info may comprise tunnel information related with the UPF110that terminates N3. In an example, the N2SM information may carry information that the AMF155may forward to the (R)AN105(e.g., the CN tunnel info corresponding to the core network address of the N3tunnel corresponding to the PDU session, one or multiple QoS profiles and the corresponding QFIs may be provided to the (R)AN105, the PDU session ID may be used by AN signaling with the UE100to indicate to the UE100the association between AN resources and a PDU session for the UE100, and/or the like). In an example, a PDU session may be associated to an S-NSSAI and a DNN. In an example, the N1SM container may contain the PDU session establishment accept that the AMF155may provide to the UE100. In an example, multiple QoS rules and QoS profiles may be included in the PDU session establishment accept within the N1SM and in the N2SM information. In an example, the Namf_Communication_N1N2MessageTransfer1305may further comprise the PDU session ID and information allowing the AMF155to know which access towards the UE100to use.

In an example, the AMF155may send to the (R)AN105an N2PDU session request1310(comprising N2SM information, NAS message (PDU session ID, N1SM container (PDU session establishment accept, and/or the like))). In an example, the AMF155may send the NAS message1310that may comprise PDU session ID and PDU session establishment accept targeted to the UE100and the N2SM information received from the SMF160within the N2PDU session request1310to the (R)AN105.

In an example, the (R)AN105may issue AN specific signaling exchange1315with the UE100that may be related with the information received from SMF160. In an example, in case of a 3GPP RAN105, an RRC connection reconfiguration procedure may take place with the UE100to establish the necessary RAN105resources related to the QoS Rules for the PDU session request1310. In an example, (R)AN105may allocate (R)AN105N3tunnel information for the PDU session. In case of dual connectivity, the master RAN105node may assign some (zero or more) QFIs to be setup to a master RAN105node and others to the secondary RAN105node. The AN tunnel info may comprise a tunnel endpoint for each involved RAN105node, and the QFIs assigned to each tunnel endpoint. A QFI may be assigned to either the master RAN105node or the secondary RAN105node. In an example, (R)AN105may forward the NAS message1310(PDU session ID, N1SM container (PDU session establishment accept)) to the UE100. The (R)AN105may provide the NAS message to the UE100if the necessary RAN105resources are established and the allocation of (R)AN105tunnel information are successful.

In an example, the N2PDU session response1320may comprise a PDU session ID, cause, N2SM information (PDU session ID, AN tunnel info, list of accepted/rejected QFI(s)), and/or the like. In an example, the AN tunnel info may correspond to the access network address of the N3tunnel corresponding to the PDU session.

In an example, the AMF155may forward the N2SM information received from (R)AN105to the SMF160via a Nsmf_PDUSession_UpdateSMContext request1330( comprising: N2SM information, request type, and/or the like). In an example, if the list of rejected QFI(s) is included in N2SM information, the SMF160may release the rejected QFI(s) associated QoS profiles.

In an example, the SMF160may initiate an N4session modification procedure1335with the UPF110. The SMF160may provide AN tunnel info to the UPF110as well as the corresponding forwarding rules. In an example, the UPF110may provide an N4session modification response1335to the SMF160160.

In an example, the SMF160may send to the AMF155an Nsmf_PDUSession_UpdateSMContext response1340(Cause). In an example, the SMF160may subscribe to the UE100mobility event notification from the AMF155(e.g. location reporting, UE100moving into or out of area of interest), after this step by invoking Namf_EventExposure_Subscribe service operation. For LADN, the SMF160may subscribe to the UE100moving into or out of LADN service area event notification by providing the LADN DNN as an indicator for the area of interest. The AMF155may forward relevant events subscribed by the SMF160.

In an example, the SMF160may send to the AMF155, a Nsmf_PDUSession_SMContextStatusNotify (release)1345. In an example, if during the procedure, any time the PDU session establishment is not successful, the SMF160may inform the AMF155by invoking Nsmf_PDUSession_SMContextStatusNotify(release)1345. The SMF160may releases any N4session(s) created, any PDU session address if allocated (e.g. IP address) and may release the association with the PCF135.

In an example, in case of PDU type IPv6, the SMF160may generate an IPv6 Router Advertisement1350and may send it to the UE100via N4and the UPF110.

In an example, if the PDU session may not be established, the SMF160may unsubscribe1360to the modifications of session management subscription data for the corresponding (SUPI, DNN, S-NSSAI), using Nudm_SDM_Unsubscribe (SUPI, DNN, S-NSSAI), if the SMF160is no more handling a PDU session of the UE100for this (DNN, S-NSSAI). In an example, if the PDU session may not be established, the SMF160may deregister1360for the given PDU session using Nudm_UECM_Deregistration (SUPI, DNN, PDU session ID).

FIG.15illustrates a service-based architecture for a 5G network regarding a control plane (CP) and a user plane (UP) interaction. This illustration may depict logical connections between nodes and functions, and its illustrated connections may not be interpreted as direct physical connections. A wireless device may form a radio access network connection with a bases station, which is connected to a User Plane (UP) Function (UPF) over a network interface providing a defined interface such as an N3interface. The UPF may provide a logical connection to a data network (DN) over a network interface such as an N6interface. The radio access network connection between the wireless device and the base station may be referred to as a data radio bearer (DRB).

The DN may be a data network used to provide an operator service, 3'rd party service such as the Internet, IP multimedia subsystem (IMS), augmented reality (AR), virtual reality (VR). In some embodiments DN may represent an edge computing network or resource, such as a mobile edge computing (MEC) network.

The wireless device also connects to the AMF through a logical N1connection. The AMF may be responsible for authentication and authorization of access requests, as well as mobility management functions. The AMF may perform other roles and functions. In a service-based view, AMF may communicate with other core network control plane functions through a service-based interface denoted as Namf.

The SMF is a network function that may be responsible for the allocation and management of IP addresses that are assigned to a wireless device as well as the selection of a UPF for traffic associated with a particular session of the wireless device. There will be typically multiple SMFs in the network, each of which may be associated with a respective group of wireless devices, base stations or UPFs. The SMF may communicate with other core network functions, in a service based view, through a service based interface denoted as Nsmf. The SMF may also connect to a UPF through a logical interface such as network interface N4.

The authentication server function (AUSF) may provide authentication services to other network functions over a service based Nausf interface. A network exposure function (NEF) can be deployed in the network to allow servers, functions and other entities such as those outside a trusted domain (operator network) to have exposure to services and capabilities within the network. In one such example, the NEF may act like a proxy between an external application server (AS) outside the illustrated network and network functions such as the PCF, the SMF, the UDM and the AMF. The external AS may provide information that may be of use in the setup of the parameters associated with a data session. The NEF may communicate with other network functions through a service based Nnef network interface. The NEF may have an interface to non-3GPP functions.

The Network Repository Function (NRF) may provide network service discovery functionality. The NRF may be specific to the Public Land Mobility Network (PLMN) or network operator, with which it is associated. The service discovery functionality can allow network functions and wireless devices connected to the network to determine where and how to access existing network functions.

The PCF may communicate with other network functions over a service based Npcf interface, and may be used to provide policy and rules to other network functions, including those within the control plane. Enforcement and application of the policies and rules may not be responsibility of the PCF. The responsibility of the functions to which the PCF transmits the policy may be responsibility of the AMF or the SMF. In one such example, the PCF may transmit policy associated with session management to the SMF. This may be used to allow for a unified policy framework with which network behavior can be governed.

The UDM may present a service based Nudm interface to communicate with other network functions. The UDM may provide data storage facilities to other network functions. Unified data storage may allow for a consolidated view of network information that may be used to ensure that the most relevant information can be made available to different network functions from a single resource. This may allow implementation of other network functions easier, as they may not need to determine where a particular type of data is stored in the network. The UDM may employ an interface, such as Nudr to connect to the UDR. The PCF may be associated with the UDM.

The PCF may have a direct interface to the UDR or may use Nudr interface to connection with UDR. The UDM may receive requests to retrieve content stored in the UDR, or requests to store content in the UDR. The UDM may be responsible for functionality such as the processing of credentials, location management and subscription management. The UDR may also support authentication credential processing, user identification handling, access authorization, registration/mobility management, subscription management, and short message service (SMS) management. The UDR may be responsible for storing data provided by the UDM. The stored data is associated with policy profile information (which may be provided by PCF) that governs the access rights to the stored data. In some embodiments, the UDR may store policy data, as well as user subscription data which may include any or all of subscription identifiers, security credentials, access and mobility related subscription data and session related data.

The Application Function (AF) may represent the non-data plane (also referred to as the non-user plane) functionality of an application deployed within a network operator domain and within a 3GPP compliant network. The AF may in internal application server (AS). The AF may interact with other core network functions through a service based Naf interface, and may access network capability exposure information, as well as provide application information for use in decisions such as traffic routing. The AF can also interact with functions such as the PCF to provide application specific input into policy and policy enforcement decisions. In many situations, the AF may not provide network services to other network functions. The AF may be often viewed as a consumer or user of services provided by other network functions. An application (application server) outside of the trusted domain (operator network), may perform many of the same functions as AF through the use of NEF.

The wireless device may communicate with network functions that are in the core network control plane (CN-UP), and the core network user plane (CN-CP). The UPF and the data network (DN) is a part of the CN-UP. The DN may be out of core network domain (cellular network domain). In the illustration (FIG.15), base station locates in CP-UP side. The base station may provide connectivity both for the CN-CP & CN-UP. AMF, SMF, AUSF, NEF, NRF, PCF, and UDM may be functions that reside within the CN-CP328, and are often referred to as control plane functions. If the AF resides in the trusted domain, the AF may communicate with other functions within CN-CP directly via the service based Naf interface. If the AF resides outside of the trusted domain, the AM may communicate with other functions within CN-CP indirectly via the NEF.

FIGS.16-20relate to edge computing. Edge computing (also referred to as mobile edge computing, or MEC) is an evolution of cloud computing that brings hosting of applications from a centralized data center to a network edge. The network edge may be closer to end users and closer to the data generated by the end user's applications. Edge computing may be acknowledged as one of the key pillars for meeting the demanding key performance indicators of 5G, in particular, low latency and bandwidth efficiency. 5G networks may be a key future target environment for MEC deployments. Applications that use high data volumes and/or require short response times (e.g., virtual reality (VR) gaming, real-time facial recognition, video surveillance, etc.) may be particularly suitable for edge computing.

As will be discussed in greater detail below, 5G systems may support edge computing by allowing a MEC system and a 5G system to collaboratively interact for purposes of traffic routing and policy control. In an example, an application may operate as a MEC system having a MEC controller and a plurality of application servers. The MEC controller may be an application function (AF) that interacts with network functions of the 5G system (e.g., a network exposure function (NEF), a policy charging function (PCF), a session management function (SMF), etc.) to influence steering of traffic between the application and a wireless device. The wireless device may obtain MEC services associated with the application by connecting via the 5G system to the MEC system. The 5G system and the MEC system may collaborate to facilitate connection of the wireless device to one or more suitable application servers. One or more of the application servers may be a central application server that is, for example, located at a data center and accessible via the internet. One or more of the applications servers may be an edge application server located at, for example, an edge of the network. The edge application server may be nearer to the wireless device. The location of the edge application server (relative to the location of the central application server) may make the edge application server more suitable for certain tasks. For example, in some scenarios, the wireless device may be able to offload computational tasks to the edge application server, whereas the central application server is too remote for offloading.

FIG.16illustrates an embodiment of a system that includes an application server controller. A wireless device is connected to a core network via a base station. The wireless device may connect to the core network control plane (CN-CP) via interface N1and/or interface N2. The wireless device may connect to the core network user plane (CN-UP) via interface N3.

The CN-UP may comprise one or more User Plane Functions (UPFs). One or more of the one or more UPFs may be used to connect the wireless device to an application server (AS) network. The AS network may comprise a plurality of application servers. The plurality of application servers may have different locations, for example, a geographical distribution. For example, there may be a central application server located within the AS network and/or one or more applications servers at different edges of the AS network. The network of ASs may be controlled by an AS controller. The AS controller may be implemented as an application function (AF) that is connected to the core network (for example, the CN CP). The AS controller may also be referred to as a MEC controller and/or an AF controller. The AS controller may be responsible for managing ASs and for locating, relocating, selecting, or reselecting an AS within the AS network. Part of the management performed by the AS controller may be to influence traffic steering within the core network.

FIG.17illustrates segmented management between a cellular network domain and a mobile edge computing (MEC) domain. A core network control plane (CN-CP) and a core network user plane (CN-UP) may belong to the cellular network domain. The CN-UP may comprise a plurality of UPFs, for example, UPF{A}, UPF{B}, UPF{C}, UPF{D}, and UPF{E}. The CN-CP may manage the CN-UP. The AS controller and one or more data networks (DNs) may belong to the MEC domain. The DNs may be referred to as data centers. As illustrated in the figure, the AS controller may manage multiple application servers, for example, an application server #1and an application server #2. The application servers may be hosted on different DNs, for example, a local DN #1and a local DN #2. Optionally, an NEF may manage the linkages between the cellular network domain and the MEC domain. Although it is illustrated separately, the NEF may belong to the CN-CP.

In an example, a location of an application server may be indicated by a DN access identifier (DNAI). The DNAI may be interpreted as an index that points to one specific access into one or more DNs. The DNAI values may be defined by an operator based on deployment and/or configuration characteristics of the core network. The DNAIs (for example, DNAI-1, DNAI-2, DNAI-3) may be used by the AS controller to interact with the CN-CP. In the figure, DNAI-1may indicate one or more areas of the CN-UP which correspond to application server #1. An area of the CN-UP which corresponds to application server #1may include the UPF{A} and the UPF{B }. In the figure, DNAI-2may indicate one or more areas of the CN-UP which correspond to application server #2. An area of the CN-UP which corresponds to application server #2may include the UPF{D}. DNAI3may also indicate an area of the CN-UP which corresponds to application server #2, and which includes the UPF{E}. The UPF{C} may not correspond to a particular application server.

In an example, an operator may internally define an area associated with a particular DNAI. The operator may define the areas arbitrarily. As an example, all UPFs that are linked to a particular application server may share a DNAI (similar to DNAI-1in the figure). As an example, DNAI correspond to a group of UPFs, and multiple DNAI may correspond to a particular application server (similar to DNAI-2and DNAI-3in the figure).

In an example, if a wireless device is in a first area, the CN-CP may determine to route application-related traffic of the wireless device to the local DN #1via the UPF{B }. This may be based on a determination that routing via the UPF{B }is more efficient than other possible routes. If the wireless device moves to a second area, the AS controller and/or core network may determine to re-route the application-related traffic of the wireless device to the local DN #1via the UPF{D}. The DNAIs may enable the cellular network domain and/or the MEC domain to map a particular application server to a particular area, or vice-versa. As an example, the DNAIs may enable the cellular network domain to manage traffic between a wireless device and one or more application servers. As an example, the DNAIs may be known to the AS controller and may be used to facilitate AS management by the AS controller. Using the DNAIs, the AS controller may be enabled to communicate with the CN-CP in order to influence, for example, routing of application-related traffic.

FIG.18Ais an example call flow for MEC discovery. A wireless device may discover MEC applications by sending a MEC discovery request to a CN-CP function. As an example, the request may include a data network name (DNN) of a local DN requesting discovery of MEC applications hosted inside the specified local DN. In some implementations, the absence of a local DN name may indicate that a discovery of all MEC applications is requested. As an example, the request may include an application identifier. The CN-CP function may determine a discovery result. The discovery may be based on registration data of MEC applications hosted by various data networks. The CN-CP function may cross-reference a particular MEC application to a particular data network, or vice-versa. The CN-CP may respond to the wireless device with the discovery result. The discovery result may include a list of one or more application identifiers and/or one or more application addresses (for example, corresponding to a particular DN). In some embodiments, the discovery results may be limited to those MEC applications available to the wireless device. In some embodiments, the discovery results may be limited to those MEC application that the wireless device is authorized to use. The one or more application addresses may be used by the wireless device for upper layer (such as TCP layer) communication with the MEC application.

In an example, a discovery request procedure of the MEC applications may be integrated with a registration procedure between the wireless device and a CN-CP function (e.g., an AMF). In an example, the discovery request procedure of the MEC applications may be integrated with a session establishment procedure between the wireless device and a CN-CP function (e.g., an SMF). The CN-CP function may notify the wireless device about changes in the discovery result, such as an application address change, through an NAS message. The wireless device may request a dedicated PDU session to handle traffic associated with a MEC application. Such a dedicated PDU session may be used for a single edge computing application or shared by multiple edge computing applications.

FIG.18Billustrates an example of how an AS controller can exert influence on traffic routing of application data within a core network. The AS controller may send an AF request to a PCF. In an example, the AF may send an AF request message to the PCF via an NEF. If the AF request message is sent via the NEF, the NEF may map external identifiers provided by the AF to internal identifiers known by the 5G system (for example, a UE ID, SUPI, etc.). In an example, the AF may send an AF request message to the PCF directly. The AF request may be sent directly to the PCF if, for example, the AF is in a trusted domain and/or deployed by an operator of the core network.

The AF request may comprise any information suitable for influencing traffic routing. Depending on the implementation and/or the capabilities of the AS controller, the AF request may contain a range of information. For example, the AF request may comprise a general request that the core network attempt to optimize the user plane configuration, specific information that the core network may use to facilitate user plane configuration, and/or specific instructions for configuration of the user plane. The AF request may comprise a traffic descriptor (an IP filter and/or an application identifier) describing the application traffic covered by the AF request message. The AF request may comprise a location of one or more applications and/or application servers, for example, a list of DNAIs. The AF request may comprise an identifier of a target wireless device, for example, a generic public subscription identifier (GPSI), user equipment (UE) group identifier. The AF request may comprise N6routing information indicating how traffic should be forwarded via an N6interface, for example, a target IP address (and/or port) in the DN to which the application traffic is requested to be tunneled. The AF request may comprise spatial and temporal validity conditions indicating one or more time intervals and/or geographic areas for when and/or where the AF request message is to be applied.

Based on the AF request message, the PCF may create policy and charging control (PCC) rules and/or other relevant information, for example, a requested Session and Service Continuity (SSC) mode, local UPF information, or any other relevant information. The PCF may send a session management policy update message to the SMF. The session management policy update message may indicate the PCC rules and/or the relevant information. The SMF then may act on the relevant information. In an example, by configuring or reconfiguring the user plane. In an example, the SMF may insert an uplink classifier (UL CL) UPF into the user plane based on the information. In an example, the SMF may trigger relocation of a PDU session anchor (PSA) UPF using SSC mode 2 or 3 procedures. As illustrated in the figure, the SMF may send a session management policy update response to the PCF. The response may be sent before or after a user plane reconfiguration. In an example, the response may include an acknowledgement that the session management policy update message has been received. In an example, the response may notify the PCF as to whether and/or how the user plane has been reconfigured.

The AF request may instruct the SMF to notify the AF when a UPF related event occurs. For example, the SMF may notify the AF when a UL CL UPF is inserted into the user plane, when an SSC mode 2 or mode 3 procedure is triggered, and/or when a PSA UPF is relocated. The AF can request to be notified before the event is to take place and/or after the event has taken place. Based on the notification, the AF may take application layer actions such as relocating application state of handle UE IP address changes.

FIG.19illustrates an example of an AS controller influencing traffic routing of application data by causing a user plane reconfiguration within a core network. As noted above, the AS controller may be implemented as an AF. The application, or aspects thereof, is accessible in three different data networks. The data networks may comprise a central network, a first local area data network, and a second local area data network. The central network has a DNAI=0and comprises a central application server. In an example, the central application server may be accessible via the internet. The first local area data network has a DNAI=1and comprises a first edge application server. The second local area data network has a DNAI=2and comprises a second edge application server. The first local area data network is associated with one or more UPFs including UPF{1}. The second local area data network is associated with one or more UPFs including UPF{2}.

Initially (before the AF request), the user plane path between the wireless device and the application is via a central UPF associated with the central network (dashed and dotted line in the figure). The location of the central UPF may be remote from the location of the wireless device. Based on the AF request, the SMF may insert a local UPF within the user plane path of the wireless device. In an example, the AF request message may indicate the DNAI of a requested area (DNAI=1). Based on the DNAI indicated by the AF request message, the SMG may select a UPF associated with the first local area data network (i.e., UPF{1}.

After the AF request, the SMF may reconfigure the user plane path. In particular, the wireless device may have a user plane path to an edge application server within the first local area data network and to the central application server (solid line in the figure). Because the first edge application server is nearer to the wireless device than the central application server, it will be understood that communication delay associated with the first edge application server may be less than the communication delay associated with the central application server. Accordingly, in some scenarios, the new user plane path (i.e., the path that is requested by the AS controller) may reduce the delays associated with offloading of certain application-related tasks.

FIG.20illustrates examples of offloading. An application may operate on a wireless device, and may require the wireless device to perform tasks. The wireless device may determine to offload tasks to an application server associated with the application. The application server may be an edge application server. The application server may be located in a data network. The data network may be a local area data network. The data network may be a cloud computing data center. The wireless device may send raw data and/or processing tasks to the application server.

The application operating on the wireless device may obtain raw data at the wireless device. The raw data may be referred to as unprocessed data. The raw data may be gathered and/or generated by the wireless device. In this example figure, the wireless device is illustrated as a vehicle. The vehicle is running, for example, a vehicle-to-everything (V2X) automatic driving application. The application may cause the wireless device to take photos of the front, right, left, and rear of the vehicle. The photos may be the raw data. The application operating on the wireless device may process the raw data to obtain a result. The result may be referred to as processed data. In this example, the result may be a driving direction. Alternatively, the wireless device may determine to offload tasks to an application server associated with the application. To offload, the wireless device may transmit the raw data to the application server. The application server may process the raw data (for example, the photos) to obtain the result (for example, the driving direction). The application may transmit the result to the wireless device. The wireless device may obtain the result by receiving the result from the application server.

In the offloading example illustrated in the figure, raw data is transmitted and a complete result is obtained. However, it will be understood that the processing of the raw data to obtain the result may comprise a plurality of processing tasks, and that offloading may be defined as having occurred when any number of these tasks are performed by the application server. In an example, the wireless device may perform one or more first processing tasks on the raw data and transmit an incomplete result to the application server. The application server may perform one or more second processing tasks on the partial (incomplete) result to obtain a complete result and transmit the complete result to the wireless device. Alternatively, the wireless device may transmit raw data and the application server may perform the one or more first processing tasks, before transmitting the partial (incomplete) result to the wireless device. The wireless device may perform the one or more second processing tasks on the incomplete result to obtain a complete result. In the present disclosure, the term unprocessed data may refer to data that is not fully processed to obtain the result, including raw data or partially-processed data.

In existing technologies, communication networks (e.g., 5G 3GPP systems) may support edge computing by allowing a MEC system and a 5G system to collaboratively interact to route traffic. The MEC system may instruct a change of a user plane path from a central application server to a local application server. The MEC system may redirect a user plane path from a central user plane function (UPF) to a local UPF. In some scenarios, the latency of the user plane path may be reduced by redirecting the user plane path to an application server which is closer to a location of the wireless device. By offloading processing tasks, the wireless device can potentially reduce its computational burden and/or conserve resources. The wireless device may offload processing tasks to the application server using an application layer that is transparent to the 5G system. The 5G system may not support collaborative interaction with the MEC system to offload the processing tasks. The existing technology may not be efficient to employ the offloading handling by a wireless device and an application. In an example, battery resources and/or computational resources of a wireless device may be limited. To conserve resources, the wireless device may prefer to connect to an application server that provides offload capability. For the wireless devices to get service within the MEC environment, an improved method for session management handling to control the offloading is needed to increase resource utilization efficiency, battery utilization and to guarantee quality of service of the wireless devices.

In existing technologies, a wireless device may benefit from offloaded processing of application data. The offloaded processing may be performed with edge computing. The edge computing may be performed by an application server associated with the application. Implementation of edge computing may require management of one or more user plane paths within a communication network (for example, a user plane path between the wireless device and the edge computing application server and/or between the wireless device and the central application server). The benefits of edge computing may be reduced if a user plane path can not be arranged and/or configured quickly and efficiently. In existing technologies, an application server associated with the application (e.g., an edge computing application server proximate to the wireless device and/or a central application server) may lack effective signaling processes for arranging and/or configuring the user plane path. For example, the application server(s) may lack information about whether offloaded processing is suitable for and/or requested by the wireless device. For example, the user plane path may be within a communication network, and the application server(s) may attempt to manage the user plane path from outside the network. For example, the wireless device may attempt to inform the application server(s) of a request for offloaded processing via an inefficient user plane path of a network, and the application server(s) may attempt to arrange for a more suitable user plane path from outside of the network. Accordingly, offloaded processing may be delayed and/or rejected, and/or an inefficient user plane path may be established. In such a case, the computational load on the wireless device may increase, and user experience may be negatively affected.

In an example, a wireless device may send a session control message to the SMF, for a PDU session, requesting offloaded processing for an application. Offloading may refer to offloading of one or more processing tasks, and may be referred to as computation offloading, task offloading, and/or processing offloading. The wireless device may receive, from the SMF, a session control response message for the PDU session indicating whether the offloading is available or not. The wireless device may determine to send data that is unprocessed by the application based on the indication that the offloading is available. The data that is unprocessed may be raw data or data that is partially processed to obtain a partial/incomplete result. The wireless device may determine to send data that is processed by the application based on the indication that the offloading is not available.

In an example, a wireless device may determine to send a request for offloaded processing of application data to an SMF. The request may be included in a first message that comprises single network slice selection assistance information (S-NSSAI). The S-NSSAI may identify a slice of a PDU session associated with the application. The first message may be, for example, a PDU session establishment request. The first message may be, for example, a PDU session modification request. Based on the first message, the SMF may determine whether to reject or accept the request for offloaded processing. The SMF may send, to the wireless device, a second message indicating a rejection or an acceptance of the request for offloaded processing of data. Having been provided with a S-NSSAI, the SMF may be able to quickly and efficiently arrange a suitable user plane path between the wireless device and an edge computing application server. For example, the user plane path that is determined may be suitable for the network slice indicated by the S-NSSAI. Accordingly, the wireless device may quickly realize the benefits of edge computing.

In an example, a wireless device may determine to send a request for offloaded processing of application data to an SMF. The request may be included in a first message that comprises a PDU session identifier. The PDU session identifier may identify a PDU session associated with the application. The first message may be, for example, a PDU session establishment request. The first message may be, for example, a PDU session modification request. Based on the first message, the SMF may determine whether to reject or accept the request for offloaded processing. The SMF may send, to the wireless device, a second message indicating a rejection or an acceptance of the request for offloaded processing of data. Having been provided with a PDU session identifier, the SMF may be able to quickly and efficiently arrange a user plane path between the wireless device and an edge computing application server. Accordingly, the wireless device may quickly realize the benefits of edge computing.

In an example, a wireless device may determine to send a request for offloaded processing of application data to an SMF. The request may be included in a PDU session establishment request. Based on the PDU session establishment request, the SMF may determine whether to reject or accept the request for offloaded processing. The SMF may send, to the wireless device, a second message indicating a rejection or an acceptance of the request for offloaded processing of data. Having been provided with the request for offloaded processing of application data, the SMF may be able to quickly and efficiently arrange a user plane path between the wireless device and an edge computing application server. Additional signaling between, for example, the wireless device and an application server of the application (e.g., a central application server and/or the edge computing application server) may be avoided. For example, the wireless device may avoid establishing a PDU session by which to communicate with the application server, and then sending a request for offloaded processing to the application server using the established PDU session, and then modifying an existing PDU session (or establishing a new PDU session) so that it is suitable for offloaded processing. Accordingly, signaling overhead in the network may be reduced and the wireless device may quickly realize the benefits of edge computing.

In an example, a wireless device may determine to send a request for offloaded processing of application data to an SMF. The request may be included in, for example, a first message comprising a PDU session establishment request. The request may be included in, for example, a first message comprising a PDU session modification request. The SMF may select one or more UPFs to serve the PDU session based on the request for offloaded processing of data. Having been notified that offloaded processing of data is requested, the SMF may be able to quickly and efficiently arrange a user plane path that is suitable for edge computing. Accordingly, the wireless device may quickly realize the benefits of edge computing.

In an example, a wireless device may determine to send a request for offloaded processing of application data to an SMF. The request may be included in, for example, a first message comprising a PDU session establishment request. The request may be included in, for example, a first message comprising a PDU session modification request. The SMF may select one or more UPFs to serve the PDU session based on the request for offloaded processing of data. Having been provided with a S-NSSAI, the SMF may be able to quickly and efficiently arrange a suitable user plane path between the wireless device and an edge computing application server. For example, the user plane path that is determined may be suitable for the network slice indicated by the S-NSSAI. Accordingly, the wireless device may quickly realize the benefits of edge computing.

In an example, the AF influence on traffic routing is enhanced to cover an exchange of computational capability/load of each application servers for an application. An application function of the application may send a message comprising one or more load status info of one or more application servers of the application to a session management function (SMF). The application function may send the message via a policy control function (PCF) and/or a network exposure function (NEF). The SMF may store the one or more load status info. The SMF may use the one or more load status info and the requesting the offloading for the application for a user plane function (UPF) selection for a packet data unit (PDU) session associated with the application. In the above, the SMF may determine whether the offloading is available or not based on the UPF selection. In an example, the SMF may determine that the offloading is available if the SMF selects a UPF with high load capacity.

FIG.21illustrates a call flow for offload determination and UPF selection in accordance with an example embodiment of the present disclosure. The figure illustrates a wireless device, a UPF, and several core network control plane functions (an SMF, a PCF, and a UDR). The wireless device may use a specific application. The application may be employed under an MEC environment. The wireless device may determine to use the application and request to establish a PDU session associated with the application. The wireless device may determine to offload processing tasks associated with the application and/or the PDU session. The wireless device may send, to the SMF, a session control message for the PDU session. The session control message may comprise an offload request. The offload request may be a request for offloading of computation and/or processing tasks to an application server. As an example, the session control message may request offloading of processing associated with the application and/or the PDU session.

In an example, the wireless device may request offloading based on at least one of a battery power level of the wireless device, computing resources of the wireless device, computing resources for the application of the wireless device, a radio quality with a serving base station, a wireless device capability, and/or the like.

In an example, the request for offloading may be based on a power level of the wireless device. As an example, the power level of a battery of the wireless device may be below a power level threshold (e.g., 20%), and the wireless device may determine to offload one or more processing tasks to the application server. The power level threshold may be determined by, for example, an operating system of the wireless device or a MEC layer of the wireless device. As an example, the user may activate a power saving mode of the wireless device and/or the application, and the wireless device may determine to offload one or more processing tasks to the application server.

In an example, the request for offloading may be based on computing resources of the wireless device. As an example, a utilization ratio of a computing capability of the wireless device may rise beyond a utilization ratio threshold (e.g., 50%), and the wireless device may determine to offload one or more processing tasks to the application server. As an example, the utilization ratio may be a percentage of the available computing resources associated with, for example, a central processing unit (CPU) or a graphics processing unit (GPU). As an example, the wireless device, or a component thereof (CPU, GPU, etc.), may be capable of a certain number of million instructions per second (MIPS), and the utilization ratio may correspond to a number of available MIPS. As an example, the utilization ratio may reflect an amount of computing resources allocated for processing tasks associated with the application. As an example, the utilization ratio may be a proportion of the amount of computing resources allocated for processing tasks associated with the application relative to an amount of unused computing resources and/or an amount of computing resources used for other processing tasks of the wireless device.

In an example, the request for offloading may be based on a radio quality with a serving base station. As an example, the radio quality may be above a radio quality threshold, and the wireless device may determine to offload one or more processing tasks to the application server. The radio quality with a serving base station may be measured as an RSRQ (Reference Signal Received Quality) and/or an RSRP (Reference Signal Received Power) of the serving base station. As an example, RSRQ of the serving base station may be above −3 dB, and the wireless device may determine to offload one or more processing tasks to the application server. As an example, RSRP of the serving base station may be above −44 dB, and the wireless device may determine to offload one or more processing tasks to the application server. The radio quality threshold may be preconfigured by a wireless device or provided by a MEC layer of the wireless device. The wireless device may receive the radio quality threshold from the serving base station. The serving base station may broadcast the radio quality threshold for the offloading or may send via a message (for example, an RRC message) to the wireless device.

In an example, the request for offloading may be based on a computation capability of the wireless device. The wireless device may be simple display without enough computational power for the application. In an example, the wireless device may comprise a display and a simple CPU so the wireless device may not capable for the computing for a processing of the application. The need of the offloading may be based on the wireless device capability. In an example, the need of the offloading may be based on the wireless device being a display for interacting with the application of the MEC. In an example, the need of the offloading may be based on the wireless device being a low complexity wireless device. The wireless device may determine to offload a processing or storage/caching task pertaining to an application.

In an example, the network may determine an offload scheme based on the wireless device status, network load, and/or the like. The offload scheme may be transmitted to the wireless device to instruct the wireless device on processing, storage/caching, transmission (e.g., determining a preferred access type), and/or the like for the running application.

In an example, the session control message may be a PDU session establishment request message, a PDU session modification request message, a service request message, and/or the like. The session control message may comprise a DNN of the application and/or an S-NSSAI of the application. The session control message may comprise information for requesting offload, facilitating offload, determining whether offload is viable, and/or determining whether offload is efficient. The session control message may comprise a power level of the wireless device, computing resources associated with the wireless device (used by the wireless device, unused by the wireless device, used by the application, available to the wireless device, etc.), a radio quality (RSRQ, RSRP of a serving base station, etc.), the wireless device capability, a number of applications, types of applications running on the wireless device, and/or the like.

The SMF may receive the session control message requesting offload. The SMF may check an authorization of the wireless device with a UDR. In an example, the SMF may check whether the application is authorized to be used by the wireless device. The SMF may check with the UDR whether the application is authorized to use offloading and/or an offloading level of the application. In an example, the offloading may be authorized for the wireless device based on a subscription information of the UDR, local policy, and/or the like. In an example, the offloading level of the application or the wireless device may comprise no offloading, partial offloading (corresponding to offloading of particular processing tasks and/or a fraction of all processing tasks), full offloading, and/or the like. The SMF may check the authorization of the offloading, the offloading level based on pre-configuration and/or a local policy. If the wireless device is authorized for the offloading, the SMF may determine the offloading of the wireless device based on the request from the wireless device.

In an example, the SMF may establish a session policy association with the PCF. The SMF may receive QoS parameter for the wireless based on the DNN, S-NSSAI, and/or the like. The QoS parameter may comprise at least one of 5G QoS Identifier (5QI), application and retention priority, reflective QoS attribute, flow bit rates, maximum packet loss rate, aggregate bit rates, and/or the like. In an example, the SMF may select a UPF for the PDU session.

In response to receiving the session control message, the SMF may select a serving UPF for the PDU session. The SMF may select the serving UPF based on at least one of a DNN, an S-NSSAI, a location of the wireless device, a serving base station, load status information of the UPF, load status information of one or more application functions, the offloading request, the authorization result of the computation, and/or the like. Although only a single UPF is illustrated, it will be understood that selection of the UPF may comprise selection of a user plane path to a particular application server (application function). The user plane path may comprise any number of UPFs. The any number of UPFs may communicate with one another using N9interfaces.

In an example, the authorization result of the offloading may indicate that the offloading is not allowed for the wireless device and/or the application. In response to the offloading being not allowed, the SMF may select the UPF based on the DNN, S-NSSAI and the location of the wireless device. In response to the offloading being not allowed, the SMF may select the UPF based on the available resources of the UPF, information about path performance between the UPF and the wireless device (e.g., delay, number of hops, and/or the like), etc. In an example, if the wireless device location corresponds to a particular DNAI, the SMF may select a UPF that is associated with the DNAI. The association information between the DNAI and the UPF may be configured by an AF that is influencing traffic routing, for example, the AS controller described above.

In an example, the authorization result of the offloading may indicate that the offloading is allowed for the wireless device and/or the application. In an example, the SMF may determine to offload computing of the wireless device to an application server based on the offloading request received from the wireless device. In an example, the SMF may determine to offload computing of the wireless device to an application server based on the offloading request received from the wireless device and the indication that offloading is allowed for the wireless device. In response to determining to offload computing of the wireless device, the SMF may select the UPF based on the DNN, S-NSSAI, a location of the wireless device, a serving base station, load status information of one or more application functions, and/or the like. In an example, the SMF may select UPF based on a location of the wireless device (e.g., area associated with the DNAI). The SMF may additionally consider load status information of one or more application functions for the UPF selection.

In an example, UPF1and UPF2may be associated with the DNAI-1which is a location of the wireless device. In an example, the load status of application function associated with the UPF1may indicate that offloading is not possible. In an example, the load status of application function associated with the UPF2may indicate that offloading is possible. The SMF may select the UPF2in response to the offloading being possible.

In an example, UPF1and UPF2may be associated with the DNAI-1which is a location of the wireless device. In an example, the load status of application function associated with the UPF1may indicate that 70% of computing power is used. In an example, the load status of application function associated with the UPF2may indicate that 50% of computing power is used. The SMF may select the UPF2in response to the offloading being possible.

In an example, UPF1may be associated with the DNAI-1and UPF2may be associated with the DNAI-2and the wireless device may locate close to the DNAI-1. A load status of a first application function associated with the DNAI-1may indicate that offloading is not possible. A load status of a second application function associated with the DNAI-2may indicate that offloading is possible. A user plane path, from the wireless device, to the UPF2may provide longer delay than a user plane path, from the wireless device, to the UPF1. The SMF, based on the offloading request, may select the UPF2for the PDU session in response to the offloading of the second application associated with the UPF2being possible.

In an example, the SMF may determine whether the offloading for the PDU session of the wireless device is available or not. The SMF may determine whether the offloading is available or not based on at least one of DNN, S-NSSAI, a location of the wireless device, a serving base station, load status information of one or more application functions, the offloading request, the authorization result of the offloading, selected UPF, and/or the like.

If the authorization result of the offloading indicates that the offloading is not allowed for the wireless device and/or the application, the SMF may determine that the offloading is not available for the wireless device. If an application (e.g., application function, application system, application server) associated with the selected UPF does not support offloading (e.g., based on the load status information) or is not capable of offloading, the SMF may determine that the offloading is not available for the PDU session.

If the authorization result of the offloading indicates that the offloading is allowed for the wireless device and/or the application, the SMF may determine that the offloading is available for the wireless device. If an application (e.g., application function, application system, application server) associated with the selected UPF supports offloading (e.g., based on the load status information), or is capable of offloading, the SMF may determine that the offloading is available for the PDU session. If the SMF selects a UPF of a local data network (e.g., local area data network), the SMF may determine that the offloading is available.

In an example, the SMF may send, to the wireless device, a session control response message for the PDU session indicating whether the offloading is available or not. The SMF may send the session control response message based on the determination of the offloading. The session control response message may be a PDU session establishment accept message, a PDU session modification message, a PDU session modification response message, and/or the like.

In an example, the wireless device may receive the session control response message for the PDU session, from the SMF, indicating whether the offloading is available or not. If the session control response message indicates that the offloading is available, the wireless device may determine to offload computing of the application associated with the PDU session to an application function of a data center. The wireless device may determine to offload computing fully or partially. If the session control response message indicates that the offloading is available, the wireless device may determine to send data that is unprocessed by the application of the wireless device. If the wireless device sends data that is unprocessed by the application to an application of a data center via the 5G system (e.g., base station to UPF), the application of the data center may process the data.

In an example, the session control response message may indicate that the offloading is not available. If the offloading is not available, the wireless device may determine do not offload computing of the application associated with the PDU session to an application of a data center. The wireless device may determine local computing without offloading to the application of the data center. If the session control response message indicates that the offloading is not available, the wireless device may determine to send data that is processed by the application of the wireless device.

In an example, the session control response message may further indicate a offloading level for the application. The offloading level may comprise a full offload, semi offload, partial offload, and/or the like. If the offloading level indicates semi offload or partial offload, the wireless device may determine to offload partially. If the wireless device determines to offload partially, the wireless device may send data that is unprocessed and data that is processed. If the wireless device determines to offload partially, the wireless device may send data that is unprocessed and data that is processed.

In an example, the session control response message may further indicate a location of an application server. The location of the application sever may comprise a center data network, a local data network, an edge data network, and/or the like. The wireless device may send the data that is unprocessed based on that the location of an application server is the local data network or the edge data network. The wireless device may determine to offload computing (e.g., computing power) based on that the location of an application server is the local data network or the edge data network.

FIG.22illustrates a call flow for load status info report procedure by an AS controller in accordance with an example embodiment of the present disclosure. The figure illustrates a UPF, several core network control plane functions (an SMF, a PCF, and a UDR) and two application function (AF1, AF2). In an example, each application function may be a AS controller.

The application function may send an AF request to the SMF. The AF request may comprise DNAI address, application function address, load status information, and/or the like. In an example, the load status information may be a offloading capability. The load status information may indicate an availability of the offloading from the application. The load status information may comprise, for example, a percentile of computation resource usage of the application function (50%, 70%). The load status information may indicate full offloading, partial offloading, no offloading, and/or the like. The load status information may indicate an idle resource of the application. The SMF may receive a first load status info from an application function1. The SMF may receive a second load status info from an application function2. The SMF may store the first and second load status info internally.

In an example, a wireless device requests a PDU session establishment requesting offloading. In response to the requesting, the SMF may determine a UPF selection for a PDU session based on the first and second load status info. If the load status of the application function1indicates a full offloading and the load status of the application function2indicates a partial offloading, the SMF may select a UPF associated with the application function1.

FIG.23illustrates a flow chart for a wireless device in accordance with an example embodiment of the present disclosure. In an example, a wireless device may send a session control message, to an SMF, requesting offload of an application. The wireless device may receive a session control response message in response to sending the session control message. The session control response message may indicate whether the offload is available or not. If the offload is available, the wireless device may determine a partial or full offload. The wireless device may send data that is unprocessed by the application, in response to the offload being available. In the present disclosure, the term unprocessed data may refer to data that is not fully processed to obtain the result, including raw data or partially-processed data. If the offload is not available, the wireless device may determine a local computing. The wireless device may send data that is processed by the application, in response to the offload not being available.

FIG.24illustrates a flow chart for an SMF in accordance with an example embodiment of the present disclosure. In an example, a SMF may receive a session control message, from a wireless device, requesting offload of an application. The SMF may determine whether offload is available or not. If offload is available based on the determination, the SMF may send a session control response message indicating that offload is available. If the offload is not available based on the determination, the SMF may send a session control response message indicating that offload is not available.

FIG.25illustrates a flow chart for an SMF regarding a UPF selection in accordance with an example embodiment of the present disclosure. In an example, a SMF may receive one or more load status information of one or more application servers for an application, from a network function. The SMF may select one or more UPFs based on the one or more load status information. The network function may be an application function (e.g., application function of MEC, MEC controller, and/or the like).

In an example, a wireless device may send, to a session management function (SMF), a session control message for a packet data unit (PDU) session requesting a offloading for an application of the wireless device. The wireless device may receive from the SMF, a session control response message for the PDU session indicating that the offloading is available. The wireless device may send data that is unprocessed by the application of the wireless device, based on the indication that the offloading is available.

In an example, offloading may refer to offloading of one or more processing tasks, and may be referred to as computation offloading, task offloading, and/or processing offloading.

In an example, a wireless device may send, to a session management function (SMF), a session control message for a packet data unit (PDU) session, wherein the session control message requests a offloading for an application of the wireless device. The wireless device may receive from the SMF, a session control response message for the PDU session indicating whether the offloading is available or not. The wireless device may send data that is unprocessed by the application of the wireless device, based on the indication that the offloading is available. In an example, the wireless device may send data that is processed by the application of the wireless device, based on the indication that the offloading is not available. In an example, the offloading may be a offloading.

In an example, the wireless device may request the offloading based on at least one of a battery power level, a computing resources, a computing resources for the application, a radio quality with a serving base station, a wireless device capability, and/or the like. The battery power level of the wireless device may below a power threshold. The computing resources of the wireless device may below a computing resources threshold. The radio quality with the serving base station may be above a radio quality threshold. The wireless device may be low complexity wireless device. The wireless device may be authorized for the offloading.

In an example, the session control response message may further indicate a offloading level for the application whether the offloading level is a full offload or a semi/partial offload. The sending the data that is unprocessed may be further based on the offloading level. The session control response message may further indicate a location of an application server whether the application server locates at center or edge of a network. The sending of the data that is unprocessed may be further based on the location of the application server.

In an example, a session management function (SMF) may receive from a wireless device, a session control message for a packet data unit (PDU) session, wherein the session control message requests a offloading for an application of the wireless device. The SMF may determine whether the offloading is available or not. The SMF may send to the wireless device, a session control response message for the PDU session indicating whether the offloading is available or not based on the determining.

In an example, the SMF may select a UPF for the PDU session based on the offloading request. The SMF may receive from a first application server (AS) which is associated with the application, a first message indicating a first computing load status of the first AS. The SMF may receive from a second AS which is associated with the application, a second message indicating a second computing load status of the second AS. The SMF may select the UPF based on the first computing load status and the second computing load status. In an example, the SMF may select a user plane function (UPF) associated to the first application in response to the first offloading status being higher than that the second offloading status. In an example, the first message may comprise at least one of the first computing load status, one or more data network access identifier (DNAI)s associated with the first AS, and/or the like.

In an example, the session control message for the PDU session may further comprise at least one of computing power of the wireless device, energy consumption information, and/or the like.

In an example, the determining may be further based on at least one of remaining battery of the wireless device, amounts of the unprocessed data, and/or the like.

In an example, the session control response message may further comprise a location of AS of the wireless device. The location of AS may indicate at least one of a center of the network, an edge of the network, a local area network, and/or the like.

The wireless device may determine to send data that is unprocessed in response to the wireless device selecting a remote computing in an AS of the application.

The AS may locate in an edge network for the wireless device.

The wireless device may determine to send data that is processed in response to the wireless device selecting a local computing inside the wireless device.

The wireless device may send to the SMF, a session modification message requesting a modification of quality of service (QoS) requirement for the application. The sending the session modification message may be based on the determining.

In an example, a session management function (SMF) may receive from a first application function (AF) of an application, a first message indicating a first load status of the first AF, wherein the first message comprising a first offloading capability of the first AF. The SMF may receive a second application function (AF) of the application, a second message indicating a second load status of the second AF, wherein the second message comprising a second offloading capability of the second AF. The SMF may receive from a wireless device, a third message request a packet data unit (PDU) session setup for the application. The SMF may determine and based on the first message and the second message, to select a first user data function (UPF) associated with the first AF.

In an example, a session management function (SMF) may receive from an application function (AF) of an application, a message comprising at least one of, a first load status of the application associated with a first data network access identifier (DNAI), a second load status of the application associated with a second DNAI, and/or the like. The SMF may receive from a wireless device, a third message request a packet data unit (PDU) session setup for the application. The SMF may determine and based on the first load status and the second load status, to select a first user data function (UPF) associated with the first DNAI.

In an example, the first load status may indicate higher computing capability than the second load status.

In this specification, a and an and similar phrases are to be interpreted as at least one and one or more. In this specification, the term may is to be interpreted as may, for example. In other words, the term may is indicative that the phrase following the term may is an example of one of a multitude of suitable possibilities that may, or may not, be employed to one or more of the various embodiments. If A and B are sets and every element of A is also an element of B, A is called a subset of B. In this specification, only non-empty sets and subsets are considered. For example, possible subsets of B={cell1, cell2} are: {cell1 }, {cell2}, and {cell1, cell2}.

In this specification, parameters (Information elements: IEs) may comprise one or more objects, and each of those objects may comprise one or more other objects. For example, if parameter (IE) N comprises parameter (IE) M, and parameter (IE) M comprises parameter (IE) K, and parameter (IE) K comprises parameter (information element) J, then, for example, N comprises K, and N comprises J. In an example embodiment, when one or more messages comprise a plurality of parameters, it implies that a parameter in the plurality of parameters is in at least one of the one or more messages but does not have to be in each of the one or more messages.

Example embodiments of the invention may be implemented using various physical and/or virtual network elements, software defined networking, virtual network functions.

While various embodiments have been described above, it should be understood that they have been presented by way of example, and not limitation. It will be apparent to persons skilled in the relevant art(s) that various changes in form and detail can be made therein without departing from the spirit and scope. In fact, after reading the above description, it will be apparent to one skilled in the relevant art(s) how to implement alternative embodiments. Thus, the present embodiments should not be limited by any of the above described exemplary embodiments. In particular, it should be noted that, for example purposes, the above explanation has focused on the example(s) using 5G AN. However, one skilled in the art will recognize that embodiments of the invention may also be implemented in a system comprising one or more legacy systems or LTE. The disclosed methods and systems may be implemented in wireless or wireline systems. The features of various embodiments presented in this invention may be combined. One or many features (method or system) of one embodiment may be implemented in other embodiments. A limited number of example combinations are shown to indicate to one skilled in the art the possibility of features that may be combined in various embodiments to create enhanced transmission and reception systems and methods.

In addition, it should be understood that any figures which highlight the functionality and advantages, are presented for example purposes. The disclosed architecture is sufficiently flexible and configurable, such that it may be utilized in ways other than that shown. For example, the actions listed in any flowchart may be re-ordered or optionally used in some embodiments.

Finally, it is the applicant's intent that only claims that include the express language means for or step for be interpreted under 35 U.S.C. 112. Claims that do not expressly include the phrase means for or step for are not to be interpreted under 35 U.S.C. 112.