Patent Publication Number: US-11641564-B2

Title: Flexible zone-based registration area tracking in a wireless network

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 62/887,829, filed Aug. 16, 2019, which is hereby incorporated by reference in its entirety. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     Examples of several of the various embodiments of the present invention are described herein with reference to the drawings. 
       FIG.  1    is a diagram of an example 5G system architecture as per an aspect of an embodiment of the present disclosure. 
       FIG.  2    is a diagram of an example 5G System architecture as per an aspect of an embodiment of the present disclosure. 
       FIG.  3    is a system diagram of an example wireless device and a network node in a 5G system as per an aspect of an embodiment of the present disclosure. 
       FIG.  4    is a system diagram of an example wireless device as per an aspect of an embodiment of the present disclosure. 
       FIG.  5 A  and  FIG.  5 B  depict two registration management state models in UE  100  and AMF  155  as per an aspect of embodiments of the present disclosure. 
       FIG.  6 A  and  FIG.  6 B  depict two connection management state models in UE  100  and AMF  155  as per an aspect of embodiments of the present disclosure. 
       FIG.  7    is diagram for classification and marking traffic as per an aspect of an embodiment of the present disclosure. 
       FIG.  8    is an example call flow as per an aspect of an embodiment of the present disclosure. 
       FIG.  9    is an example call flow as per an aspect of an embodiment of the present disclosure. 
       FIG.  10    is an example call flow as per an aspect of an embodiment of the present disclosure. 
       FIG.  11    is an example call flow as per an aspect of an embodiment of the present disclosure. 
       FIG.  12    is an example call flow as per an aspect of an embodiment of the present disclosure. 
       FIG.  13    is an example call flow as per an aspect of an embodiment of the present disclosure. 
       FIG.  14    is an example architecture of a 5G system as per an aspect of an embodiment of the present disclosure. 
       FIG.  14 A  is an example non-terrestrial network architecture as an aspect of an embodiment of the present disclosure. 
       FIG.  14 B  is an example non-terrestrial network architecture as an aspect of an embodiment of the present disclosure. 
       FIG.  15    is an example earth orbits of example satellites. 
       FIG.  16    is an example figure of different types of non-terrestrial network platforms. 
       FIG.  17    shows examples of propagation delay corresponding to NTNs of different altitudes. 
       FIG.  18    is an example architecture of a 5G system having a 5G core network that provides service to different types of access networks as per an aspect of an embodiment of the present disclosure. 
       FIG.  19    depicts an architecture (left side) and coverage map (right side) of a deployment scenario in which one public land mobile network (e.g. PLMN A) provides both a non-terrestrial access network and a terrestrial access network as per an aspect of an embodiment of the present disclosure. 
       FIG.  20    depicts an architecture (left side) and coverage map (right side) of a scenario in which two different public land mobile networks (e.g. PLMN A and PLMN B) respectively provide a non-terrestrial access network and a terrestrial access network. 
       FIG.  21    illustrates an example registration area representing as a tracking area (TA). 
       FIG.  22 A  depicts an example formulate of zone identity based on the geographical zone configuration parameter. 
       FIG.  22 B  depicts an example zone identity numbering based on the formulae given in  FIG.  22 A . 
       FIG.  23 A  depicts an example point on the surface of the ellipsoid and its co-ordinates. 
       FIG.  23 B  depicts an example coding of an ellipsoid point comprising S, degrees of latitude, degrees of longitude. 
       FIG.  24 A  depicts an example ellipsoid point with uncertainty circle. 
       FIG.  24 B  depicts an example coding of an ellipsoid point comprising S, degrees of latitude, degrees of longitude. 
       FIG.  25    depicts an example Universal Transverse Mercator (UTM) coordinate system. 
       FIG.  26    depicts an example horizontal latitude bands for UTM coordinate system. 
       FIG.  27    illustrates an example embodiment of a present disclosure. 
       FIG.  28    illustrates an example embodiment of a present disclosure. 
       FIG.  29    illustrates an example embodiment of a present disclosure. 
       FIG.  30    illustrates an example embodiment of a present disclosure. 
       FIG.  31    illustrates an example embodiment of a present disclosure. 
       FIG.  32    illustrates an example flow chart of a present disclosure. 
       FIG.  33    illustrates an example flow chart of a present disclosure. 
       FIG.  34    illustrates an example embodiment of a present disclosure. 
       FIG.  35    illustrates an example embodiment of a present disclosure. 
       FIG.  36    illustrates an example embodiment of a present disclosure. 
       FIG.  37    illustrates an example embodiment of a present disclosure. 
       FIG.  38    is a flow diagram of an aspect of an example embodiment of the present disclosure. 
       FIG.  39    is a flow diagram of an aspect of an example embodiment of the present disclosure. 
       FIG.  40    is a flow diagram of an aspect of an example embodiment of the present disclosure. 
       FIG.  41    is a flow diagram of an aspect of an example embodiment of the present disclosure. 
    
    
     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: 
     5G 5th generation mobile networks 
     5GC 5G Core Network 
     5GS 5G System 
     5G-AN 5G Access Network 
     5QI 5G QoS Indicator 
     ACK Acknowledgement 
     AF Application Function 
     AMF Access and Mobility Management Function 
     AN Access Network 
     CDR Charging Data Record 
     CCNF Common Control Network Functions 
     CIoT Cellular IoT 
     CN Core Network 
     CP Control Plane 
     DDN Downlink Data Notification 
     DL Downlink 
     DN Data Network 
     DNN Data Network Name 
     DRX Discontinuous Reception 
     eNB Evolved Node B 
     F-TEID Fully Qualified TEID 
     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 
     N3IWF Non-3GPP InterWorking Function 
     NAI Network Access Identifier 
     NAS Non-Access Stratum 
     NB-IoT Narrow Band IoT 
     NEF Network Exposure Function 
     NF Network Function 
     NGAP Next Generation Application Protocol 
     ng-eNB Next Generation Evolved Node B 
     NG-RAN Next Generation Radio Access Network 
     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 
     RAN Radio Access Network 
     QFI QoS Flow Identity 
     RM Registration Management 
     S1-AP S1 Application Protocol 
     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 
     SUCI Served User Correlation ID 
     SUPI Subscriber Permanent Identifier 
     TEID Tunnel Endpoint Identifier 
     UE User Equipment 
     UL Uplink 
     UL CL Uplink Classifier 
     UPF User Plane Function 
     VPLMN Visited Public Land Mobile Network 
     V2X Vehicle to everything 
     Example  FIG.  1    and  FIG.  2    depict 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-RAN  105  and/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 example  FIG.  1    and example  FIG.  2    where 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 in  FIG.  3    and  FIG.  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, AMF  155 , may include the following functionalities (some of the AMF  155  functionalities may be supported in a single instance of an AMF  155 ): termination of RAN  105  CP interface (N2), termination of NAS (N1), NAS ciphering and integrity protection, registration management, connection management, reachability management, mobility management, lawful intercept (for AMF  155  events and interface to LI system), provide transport for session management, SM messages between UE  100  and SMF  160 , transparent proxy for routing SM messages, access authentication, access authorization, provide transport for SMS messages between UE  100  and SMSF, security anchor function, SEA, interaction with the AUSF  150  and the UE  100 , receiving the intermediate key established as a result of the UE  100  authentication 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 AMF  155  may support non-3GPP access networks through N2 interface with N3IWF  170 , NAS signaling with a UE  100  over N3IWF  170 , authentication of UEs connected over N3IWF  170 , management of mobility, authentication, and separate security context state(s) of a UE  100  connected via non-3GPP access  165  or connected via 3GPP access  105  and non-3GPP access  165  simultaneously, support of a coordinated RM context valid over 3GPP access  105  and non 3GPP access  165 , support of CM management contexts for the UE  100  for connectivity over non-3GPP access, and/or the like. 
     In an example, an AMF  155  region may comprise one or multiple AMF  155  sets. The AMF  155  set may comprise some AMF  155  that serve a given area and/or network slice(s). In an example, multiple AMF  155  sets may be per AMF  155  region 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 UE  100 . DN  115  access identifier (DNAI), for a DNN, may be an identifier of a user plane access to a DN  115 . Initial registration may be related to a UE  100  registration in RM-DEREGISTERED  500 ,  520  states. N2AP UE  100  association may be a logical per UE  100  association between a 5G AN node and an AMF  155 . N2AP UE-TNLA-binding may be a binding between a N2AP UE  100  association and a specific transport network layer, TNL association for a given UE  100 . 
     In an example, session management function, SMF  160 , may include one or more of the following functionalities (one or more of the SMF  160  functionalities may be supported in a single instance of a SMF  160 ): session management (e.g. session establishment, modify and release, including tunnel maintain between UPF  110  and AN  105  node), UE  100  IP address allocation &amp; management (including optional authorization), selection and control of UP function(s), configuration of traffic steering at UPF  110  to 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 AMF  155  over N2 to (R)AN  105 , 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 DN  115  for transport of signaling for PDU session authorization/authentication by external DN  115 , and/or the like. 
     In an example, a user plane function, UPF  110 , may include one or more of the following functionalities (some of the UPF  110  functionalities may be supported in a single instance of a UPF  110 ): anchor point for Intra-/Inter-RAT mobility (when applicable), external PDU session point of interconnect to DN  115 , packet routing &amp; 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 UE  100  IP address management may include allocation and release of the UE  100  IP address and/or renewal of the allocated IP address. The UE  100  may set a requested PDU type during a PDU session establishment procedure based on its IP stack capabilities and/or configuration. In an example, the SMF  160  may select PDU type of a PDU session. In an example, if the SMF  160  receives a request with PDU type set to IP, the SMF  160  may select PDU type IPv4 or IPv6 based on DNN configuration and/or operator policies. In an example, the SMF  160  may provide a cause value to the UE  100  to indicate whether the other IP version is supported on the DNN. In an example, if the SMF  160  receives a request for PDU type IPv4 or IPv6 and the requested IP version is supported by the DNN the SMF  160  may select the requested PDU type. 
     In an example embodiment, the 5GC elements and UE  100  may support the following mechanisms: during a PDU session establishment procedure, the SMF  160  may send the IP address to the UE  100  via 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 UDM  140  and/or based on the configuration on a per-subscriber, per-DNN basis. 
     User plane function(s) (UPF  110 ) may handle the user plane path of PDU sessions. A UPF  110  that provides the interface to a data network may support functionality of a PDU session anchor. 
     In an example, a policy control function, PCF  135 , 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, NEF  125 , may provide means to securely expose the services and capabilities provided by the 3GPP network functions, translate between information exchanged with the AF  145  and information exchanged with the internal network functions, receive information from other network functions, and/or the like. 
     In an example, a network repository function, NRF  130  may 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 NSSF  120  may select a set of network slice instances serving the UE  100 , may determine allowed NSSAI. In an example, the NSSF  120  may determine the AMF  155  set to be employed to serve the UE  100 , and/or, based on configuration, determine a list of candidate AMF  155 ( s )  155  by querying the NRF  130 . 
     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 AUSF  150  may support authentication server function (AUSF  150 ). 
     In an example, an application function (AF), AF  145 , 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 NEF  125 ) to interact with relevant network functions. 
     In an example, control plane interface between the (R)AN  105  and the 5G core may support connection of multiple different kinds of AN(s) (e.g. 3GPP RAN  105 , N3IWF  170  for Un-trusted access  165 ) to the 5GC via a control plane protocol. In an example, an N2 AP protocol may be employed for both the 3GPP access  105  and non-3GPP access  165 . In an example, control plane interface between the (R)AN  105  and the 5G core may support decoupling between AMF  155  and other functions such as SMF  160  that may need to control the services supported by AN(s) (e.g. control of the UP resources in the AN  105  for a PDU session). 
     In an example, the 5GC may provide policy information from the PCF  135  to the UE  100 . In an example, the policy information may comprise: access network discovery and selection policy, UE  100  route 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 example  FIG.  5 A  and  FIG.  5 B , the registration management, RM may be employed to register or de-register a UE/user  100  with the network and establish the user context in the network. Connection management may be employed to establish and release the signaling connection between the UE  100  and the AMF  155 . 
     In an example, a UE  100  may register with the network to receive services that require registration. In an example, the UE  100  may 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 example  FIG.  8    and  FIG.  9    may involve execution of network access control functions (e.g. user authentication and access authorization based on subscription profiles in UDM  140 ). Example  FIG.  9    is a continuation of the initial registration procedure depicted in  FIG.  8   . As a result of the initial registration procedure, the identity of the serving AMF  155  may be registered in a UDM  140 . 
     In an example, the registration management, RM procedures may be applicable over both 3GPP access  105  and non 3GPP access  165 . 
     An example  FIG.  5 A  may depict the RM states of a UE  100  as observed by the UE  100  and AMF  155 . In an example embodiment, two RM states may be employed in the UE  100  and the AMF  155  that may reflect the registration status of the UE  100  in the selected PLMN: RM-DEREGISTERED  500 , and RM-REGISTERED  510 . In an example, in the RM DEREGISTERED state  500 , the UE  100  may not be registered with the network. The UE  100  context in the AMF  155  may not hold valid location or routing information for the UE  100  so the UE  100  may not be reachable by the AMF  155 . In an example, the UE  100  context may be stored in the UE  100  and the AMF  155 . In an example, in the RM REGISTERED state  510 , the UE  100  may be registered with the network. In the RM-REGISTERED  510  state, the UE  100  may receive services that may require registration with the network. 
     In an example embodiment, two RM states may be employed in AMF  155  for the UE  100  that may reflect the registration status of the UE  100  in the selected PLMN: RM-DEREGISTERED  520 , and RM-REGISTERED  530 . 
     As depicted in example  FIG.  6 A  and  FIG.  6 B , connection management, CM, may comprise establishing and releasing a signaling connection between a UE  100  and an AMF  155  over N1 interface. The signaling connection may be employed to enable NAS signaling exchange between the UE  100  and the core network. The signaling connection between the UE  100  and the AMF  155  may comprise both the AN signaling connection between the UE  100  and the (R)AN  105  (e.g. RRC connection over 3GPP access) and the N2 connection for the UE  100  between the AN and the AMF  155 . 
     As depicted in example  FIG.  6 A  and  FIG.  6 B , two CM states may be employed for the NAS signaling connectivity of the UE  100  with the AMF  155 , CM-IDLE  600 ,  620  and CM-CONNECTED  610 ,  630 . A UE  100  in CM-IDLE  600  state may be in RM-REGISTERED  510  state and may have no NAS signaling connection established with the AMF  155  over N1. The UE  100  may perform cell selection, cell reselection, PLMN selection, and/or the like. A UE  100  in CM-CONNECTED  610  state may have a NAS signaling connection with the AMF  155  over N1. 
     In an example embodiment two CM states may be employed for the UE  100  at the AMF  155 , CM-IDLE  620  and CM-CONNECTED  630 . 
     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 AMF  155 , based on network configuration, may provide assistance information to the NG RAN  105 , to assist the NG RAN&#39;s  105  decision whether the UE  100  may be sent to RRC inactive state. When a UE  100  is CM-CONNECTED  610  with RRC inactive state, the UE  100  may resume the RRC connection due to uplink data pending, mobile initiated signaling procedure, as a response to RAN  105  paging, to notify the network that it has left the RAN  105  notification 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 UE  100  and the AMF  155  to establish the NAS signaling connection for the UE  100  in CM-IDLE  600  state. The procedure of releasing the NAS signaling connection may be initiated by the 5G (R)AN  105  node or the AMF  155 . 
     In an example, reachability management of a UE  100  may detect whether the UE  100  is reachable and may provide the UE  100  location (e.g. access node) to the network to reach the UE  100 . Reachability management may be done by paging the UE  100  and the UE  100  location tracking. The UE  100  location tracking may include both UE  100  registration area tracking and UE  100  reachability tracking. The UE  100  and the AMF  155  may negotiate UE  100  reachability characteristics in CM-IDLE  600 ,  620  state during registration and registration update procedures. 
     In an example, two UE  100  reachability categories may be negotiated between a UE  100  and an AMF  155  for CM-IDLE  600 ,  620  state. 1) UE  100  reachability allowing mobile device terminated data while the UE  100  is CM-IDLE  600  mode. 2) Mobile initiated connection only (MICO) mode. The 5GC may support a PDU connectivity service that provides exchange of PDUs between the UE  100  and a data network identified by a DNN. The PDU connectivity service may be supported via PDU sessions that are established upon request from the UE  100 . 
     In an example, a PDU session may support one or more PDU session types. PDU sessions may be established (e.g. upon UE  100  request), modified (e.g. upon UE  100  and 5GC request) and/or released (e.g. upon UE  100  and 5GC request) using NAS SM signaling exchanged over N1 between the UE  100  and the SMF  160 . Upon request from an application server, the 5GC may be able to trigger a specific application in the UE  100 . When receiving the trigger, the UE  100  may send it to the identified application in the UE  100 . The identified application in the UE  100  may 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 example  FIG.  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 UPF  110  (CN_UP)  110 , AN  105  and/or the UE  100 . In an example, packets may arrive from and/or destined to the application/service layer  730  of UE  100 , UPF  110  (CN_UP)  110 , and/or the AF  145 . 
     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 N3 and/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)AN  105  as a QoS profile over N2 at 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 SMF  160  may allocate the QFI for a QoS flow and may derive QoS parameters from the information provided by the PCF  135 . In an example, the SMF  160  may provide the QFI together with the QoS profile containing the QoS parameters of a QoS flow to the (R)AN  105 . 
     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, 5GC may support edge computing and may enable operator(s) and 3rd party services to be hosted close to the UE&#39;s access point of attachment. The 5G core network may select a UPF  110  close to the UE  100  and may execute the traffic steering from the UPF  110  to the local data network via a N6 interface. In an example, the selection and traffic steering may be based on the UE&#39;s  100  subscription data, UE  100  location, the information from application function AF  145 , 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 UPF  110  to 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 UE  100  and 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 NEF  125 , QoS and charging where PCF  135  may 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 network  105 , 5G core network and a UE  100 , 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 UE  100  in the serving PLMN for the current registration area. 
     In an example, a PDU connectivity service may provide exchange of PDUs between a UE  100  and a data network. A PDU session may be an association between the UE  100  and the data network, DN  115 , 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 AMF  155  that 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 UE  100  may be changed at any time while the UE  100  may be registered with the network, and may be initiated by the network, or the UE  100 . 
     In an example, a periodic registration update may be UE  100  re-registration at expiry of a periodic registration timer. A requested NSSAI may be a NSSAI that the UE  100  may 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 UPF  110  functionality that aims at diverting uplink traffic, based on filter rules provided by the SMF  160 , towards data network, DN  115 . 
     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 example  FIG.  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 NSSF  120  may store the mapping information between slice instance ID and NF ID (or NF address). 
     In an example, a UE  100  may 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 AMF  155  instance serving the UE  100  logically may belong to a network slice instance serving the UE  100 . 
     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 UE  100  may be selected by CN. 
     In an example, subscription data may include the S-NSSAI(s) of the network slices that the UE  100  subscribes 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 UE  100  may subscribe to more than 8 S-NSSAIs. 
     In an example, a UE  100  may be configured by the HPLMN with a configured NSSAI per PLMN. Upon successful completion of a UE&#39;s registration procedure, the UE  100  may obtain from the AMF  155  an 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 UE  100  may 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 AMF  155  that 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 UE  100  registers with a PLMN, if the UE  100  for the PLMN has a configured NSSAI or an allowed NSSAI, the UE  100  may 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 UE  100  attempts 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 UE  100  registers with a PLMN, if for the PLMN the UE  100  has no configured NSSAI or allowed NSSAI, the RAN  105  may route NAS signaling from/to the UE  100  to/from a default AMF  155 . 
     In an example, the network, based on local policies, subscription changes and/or UE  100  mobility, may change the set of permitted network slice(s) to which the UE  100  is registered. In an example, the network may perform the change during a registration procedure or trigger a notification towards the UE  100  of the change of the supported network slices using an RM procedure (which may trigger a registration procedure). The network may provide the UE  100  with 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 UE  100  should be served by a different AMF  155  based on network slice(s) aspects, the AMF  155  that first received the registration request may redirect the registration request to another AMF  155  via the RAN  105  or via direct signaling between the initial AMF  155  and the target AMF  155 . 
     In an example, the network operator may provision the UE  100  with network slice selection policy (NSSP). The NSSP may comprise one or more NSSP rules. 
     In an example, if a UE  100  has one or more PDU sessions established corresponding to a specific S-NSSAI, the UE  100  may route the user data of the application in one of the PDU sessions, unless other conditions in the UE  100  may prohibit the use of the PDU sessions. If the application provides a DNN, then the UE  100  may consider the DNN to determine which PDU session to use. In an example, if the UE  100  does not have a PDU session established with the specific S-NSSAI, the UE  100  may 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 RAN  105  to select a proper resource for supporting network slicing in the RAN  105 , the RAN  105  may be aware of the network slices used by the UE  100 . 
     In an example, an AMF  155  may select an SMF  160  in a network slice instance based on S-NSSAI, DNN and/or other information e.g. UE  100  subscription and local operator policies, and/or the like, when the UE  100  triggers the establishment of a PDU session. The selected SMF  160  may 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 UE  100  may access, when the UE  100  is aware or configured that privacy considerations may apply to NSSAI, the UE  100  may not include NSSAI in NAS signaling unless the UE  100  has a NAS security context and the UE  100  may 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 UE  100  during 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 example  FIG.  8    and  FIG.  9   , a registration procedure may be performed by the UE  100  to get authorized to receive services, to enable mobility tracking, to enable reachability, and/or the like. 
     In an example, the UE  100  may send to the (R)AN  105  an AN message  805  (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, UE  100  5GC 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 UE  100  wants to perform an initial registration (e.g. the UE  100  is in RM-DEREGISTERED state), a mobility registration update (e.g., the UE  100  is in RM-REGISTERED state and initiates a registration procedure due to mobility), a periodic registration update (e.g., the UE  100  is 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 UE  100  is in limited service state). In an example, if the UE  100  performing an initial registration (e.g., the UE  100  is in RM-DEREGISTERED state) to a PLMN for which the UE  100  does not already have a 5G-GUTI, the UE  100  may 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 UE  100  received a UE  100  configuration update command indicating that the UE  100  needs to re-register and the 5G-GUTI is invalid, the UE  100  may 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 UE  100  does not have a valid 5G-GUTI available; the PEI may be included when the UE  100  has no SUPI and no valid 5G-GUTI. In other cases, the 5G-GUTI may be included and it may indicate the last serving AMF  155 . If the UE  100  is 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 UE  100  may not provide over the 3GPP access the 5G-GUTI allocated by the AMF  155  during the registration procedure over the non-3GPP access. If the UE  100  is 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 UE  100  may not provide over the non-3GPP access the 5G-GUTI allocated by the AMF  155  during the registration procedure over the 3GPP access. The UE  100  may provide the UE&#39;s usage setting based on its configuration. In case of initial registration or mobility registration update, the UE  100  may 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 AMF  155  produce 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 UE  100  is connected to the two AMF  155  belonging 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 UE  100  may 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 UE  100  is outside the area of availability of the LADN. The follow on request may be included when the UE  100  may have pending uplink signaling and the UE  100  may not include PDU session(s) to be re-activated, or the registration type may indicate the UE  100  may want to perform an emergency registration. 
     In an example, if a SUPI is included or the 5G-GUTI does not indicate a valid AMF  155 , the (R)AN  105 , based on (R)AT and requested NSSAI, if available, may selects  808  an AMF  155 . If UE  100  is in CM-CONNECTED state, the (R)AN  105  may forward the registration request message to the AMF  155  based on the N2 connection of the UE. If the (R)AN  105  may not select an appropriate AMF  155 , it may forward the registration request to an AMF  155  which has been configured, in (R)AN  105 , to perform AMF  155  selection  808 . 
     In an example, the (R)AN  105  may send to the new AMF  155  an N2 message  810  (comprising: N2 parameters, RM-NAS registration request (registration type, SUPI or 5G-GUTI, last visited TAI (if available), security parameters, requested NSSAI, mapping of requested NSSAI, UE  100  5GC 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 N2 parameters may comprise the selected PLMN ID, location information, cell identity and the RAT type related to the cell in which the UE  100  is camping. In an example, when NG-RAN is used, the N2 parameters may include the establishment cause. 
     In an example, the new AMF  155  may send to the old AMF  155  a Namf_Communication_UEContextTransfer (complete registration request)  815 . In an example, if the UE&#39;s 5G-GUTI was included in the registration request and the serving AMF  155  has changed since last registration procedure, the new AMF  155  may invoke the Namf_Communication_UEContextTransfer service operation  815  on the old AMF  155  including the complete registration request IE, which may be integrity protected, to request the UE&#39;s SUPI and MM Context. The old AMF  155  may use the integrity protected complete registration request IE to verify if the context transfer service operation invocation corresponds to the UE  100  requested. In an example, the old AMF  155  may transfer the event subscriptions information by each NF consumer, for the UE, to the new AMF  155 . In an example, if the UE  100  identifies itself with PEI, the SUPI request may be skipped. 
     In an example, the old AMF  155  may send to new AMF  155  a response  815  to Namf_Communication_UEContextTransfer (SUPI, MM context, SMF  160  information, PCF ID). In an example, the old AMF  155  may respond to the new AMF  155  for the Namf_Communication_UEContextTransfer invocation by including the UE&#39;s SUPI and MM context. In an example, if old AMF  155  holds information about established PDU sessions, the old AMF  155  may include SMF  160  information including S-NSSAI(s), SMF  160  identities and PDU session ID. In an example, if old AMF  155  holds information about active NGAP UE-TNLA bindings to N3IWF, the old AMF  155  may include information about the NGAP UE-TNLA bindings. 
     In an example, if the SUPI is not provided by the UE  100  nor retrieved from the old AMF  155  the identity request procedure  820  may be initiated by the AMF  155  sending an identity request message to the UE  100  requesting the SUCI. 
     In an example, the UE  100  may respond with an identity response message  820  including the SUCI. The UE  100  may derive the SUCI by using the provisioned public key of the HPLMN. 
     In an example, the AMF  155  may decide to initiate UE  100  authentication  825  by invoking an AUSF  150 . The AMF  155  may select an AUSF  150  based on SUPI or SUCI. In an example, if the AMF  155  is configured to support emergency registration for unauthenticated SUPIs and the UE  100  indicated registration type emergency registration the AMF  155  may skip the authentication and security setup or the AMF  155  may accept that the authentication may fail and may continue the registration procedure. 
     In an example, the authentication  830  may be performed by Nudm_UEAuthenticate_Get operation. The AUSF  150  may discover a UDM  140 . In case the AMF  155  provided a SUCI to AUSF  150 , the AUSF  150  may return the SUPI to AMF  155  after the authentication is successful. In an example, if network slicing is used, the AMF  155  may decide if the registration request needs to be rerouted where the initial AMF  155  refers to the AMF  155 . In an example, the AMF  155  may initiate NAS security functions. In an example, upon completion of NAS security function setup, the AMF  155  may 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 AMF  155 . The 5G-AN may use the security context to protect the messages exchanged with the UE. 
     In an example, new AMF  155  may send to the old AMF  155  Namf_Communication_RegistrationCompleteNotify  835 . If the AMF  155  has changed, the new AMF  155  may notify the old AMF  155  that the registration of the UE  100  in the new AMF  155  may 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 AMF  155  may invoke the Namf_Communication_RegistrationCompleteNotify service operation with a reject indication reason code towards the old AMF  155 . The old AMF  155  may continue as if the UE  100  context 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 AMF  155  may determine which PDU session may not be supported in the new registration area. The new AMF  155  may 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 AMF  155 . The new AMF  155  may modify the PDU session status correspondingly. The old AMF  155  may inform the corresponding SMF  160 ( s ) to locally release the UE&#39;s SM context by invoking the Nsmf_PDUSession_ReleaseSMContext service operation. 
     In an example, the new AMF  155  may send to the UE  100  an identity request/response  840  (e.g., PEI). If the PEI was not provided by the UE  100  nor retrieved from the old AMF  155 , the identity request procedure may be initiated by AMF  155  sending an identity request message to the UE  100  to retrieve the PEI. The PEI may be transferred encrypted unless the UE  100  performs emergency registration and may not be authenticated. For an emergency registration, the UE  100  may have included the PEI in the registration request. 
     In an example, the new AMF  155  may initiate ME identity check  845  by invoking the N5g-eir_EquipmentIdentityCheck_Get service operation  845 . 
     In an example, the new AMF  155 , based on the SUPI, may select  905  a UDM  140 . The UDM  140  may select a UDR instance. In an example, the AMF  155  may select a UDM  140 . 
     In an example, if the AMF  155  has changed since the last registration procedure, or if the UE  100  provides a SUPI which may not refer to a valid context in the AMF  155 , or if the UE  100  registers to the same AMF  155  it has already registered to a non-3GPP access (e.g., the UE  100  is registered over a non-3GPP access and may initiate the registration procedure to add a 3GPP access), the new AMF  155  may register with the UDM  140  using Nudm_UECM_Registration  910  and may subscribe to be notified when the UDM  140  may deregister the AMF  155 . The UDM  140  may store the AMF  155  identity associated to the access type and may not remove the AMF  155  identity associated to the other access type. The UDM  140  may store information provided at registration in UDR, by Nudr_UDM_Update. In an example, the AMF  155  may retrieve the access and mobility subscription data and SMF  160  selection subscription data using Nudm_SDM_Get  915 . The UDM  140  may retrieve this information from UDR by Nudr_UDM_Query(access and mobility subscription data). After a successful response is received, the AMF  155  may subscribe to be notified using Nudm_SDM_Subscribe  920  when the data requested may be modified. The UDM  140  may subscribe to UDR by Nudr_UDM_Subscribe. The GPSI may be provided to the AMF  155  in the subscription data from the UDM  140  if the GPSI is available in the UE  100  subscription data. In an example, the new AMF  155  may provide the access type it serves for the UE  100  to the UDM  140  and the access type may be set to 3GPP access. The UDM  140  may store the associated access type together with the serving AMF  155  in UDR by Nudr_UDM_Update. The new AMF  155  may create an MM context for the UE  100  after getting the mobility subscription data from the UDM  140 . In an example, when the UDM  140  stores the associated access type together with the serving AMF  155 , the UDM  140  may initiate a Nudm_UECM_DeregistrationNotification  921  to the old AMF  155  corresponding to 3GPP access. The old AMF  155  may remove the MM context of the UE. If the serving NF removal reason indicated by the UDM  140  is initial registration, then the old AMF  155  may invoke the Namf_EventExposure_Notify service operation towards all the associated SMF  160   s  of the UE  100  to notify that the UE  100  is deregistered from old AMF  155 . The SMF  160  may release the PDU session(s) on getting this notification. In an example, the old AMF  155  may unsubscribe with the UDM  140  for subscription data using Nudm_SDM_unsubscribe  922 . 
     In an example, if the AMF  155  decides to initiate PCF  135  communication, e.g. the AMF  155  has not yet obtained access and mobility policy for the UE  100  or if the access and mobility policy in the AMF  155  are no longer valid, the AMF  155  may select  925  a PCF  135 . If the new AMF  155  receives a PCF ID from the old AMF  155  and successfully contacts the PCF  135  identified by the PCF ID, the AMF  155  may select the (V-)PCF identified by the PCF ID. If the PCF  135  identified by the PCF ID may not be used (e.g. no response from the PCF  135 ) or if there is no PCF ID received from the old AMF  155 , the AMF  155  may select  925  a PCF  135 . 
     In an example, the new AMF  155  may perform a policy association establishment  930  during registration procedure. If the new AMF  155  contacts the PCF  135  identified by the (V-)PCF ID received during inter-AMF  155  mobility, the new AMF  155  may include the PCF-ID in the Npcf_AMPolicyControl Get operation. If the AMF  155  notifies the mobility restrictions (e.g. UE  100  location) to the PCF  135  for adjustment, or if the PCF  135  updates the mobility restrictions itself due to some conditions (e.g. application in use, time and date), the PCF  135  may provide the updated mobility restrictions to the AMF  155 . 
     In an example, the PCF  135  may invoke Namf_EventExposure_Subscribe service operation  935  for UE  100  event subscription. 
     In an example, the AMF  155  may send to the SMF  160  a Nsmf_PDUSession_UpdateSMContext  936 . In an example, the AMF  155  may invoke the Nsmf_PDUSession_UpdateSMContext if the PDU session(s) to be re-activated is included in the registration request. The AMF  155  may send Nsmf_PDUSession_UpdateSMContext request to SMF  160 ( s ) associated with the PDU session(s) to activate user plane connections of the PDU session(s). The SMF  160  may decide to trigger e.g. the intermediate UPF  110  insertion, removal or change of PSA. In the case that the intermediate UPF  110  insertion, 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 N11 and N2 interactions to update the N3 user plane between (R)AN  105  and 5GC. The AMF  155  may invoke the Nsmf_PDUSession_ReleaseSMContext service operation towards the SMF  160  if any PDU session status indicates that it is released at the UE  100 . The AMF  155  may invoke the Nsmf_PDUSession_ReleaseSMContext service operation towards the SMF  160  in order to release any network resources related to the PDU session. 
     In an example, the new AMF  155  may send to a N3IWF an N2 AMF  155  mobility request  940 . If the AMF  155  has changed, the new AMF  155  may create an NGAP UE  100  association towards the N3IWF to which the UE  100  is connected. In an example, the N3IWF may respond to the new AMF  155  with an N2 AMF  155  mobility response  940 . 
     In an example, the new AMF  155  may send to the UE  100  a registration accept  955  (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 AMF  155  may send the registration accept message to the UE  100  indicating that the registration request has been accepted. 5G-GUTI may be included if the AMF  155  allocates a new 5G-GUTI. If the AMF  155  allocates a new registration area, it may send the registration area to the UE  100  via registration accept message  955 . If there is no registration area included in the registration accept message, the UE  100  may consider the old registration area as valid. In an example, mobility restrictions may be included in case mobility restrictions may apply for the UE  100  and registration type may not be emergency registration. The AMF  155  may indicate the established PDU sessions to the UE  100  in the PDU session status. The UE  100  may 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 UE  100  is connected to the two AMF  155  belonging to different PLMN via 3GPP access and non-3GPP access then the UE  100  may 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 AMF  155  may 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 AMF  155  may include in the registration accept message  955  the LADN information for LADNs that are available within the registration area determined by the AMF  155  for the UE. If the UE  100  included MICO mode in the request, then AMF  155  may respond whether MICO mode may be used. The AMF  155  may 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 AMF  155  may perform a UE/RAN radio information and compatibility request procedure to check the compatibility of the UE  100  and RAN radio capabilities related to IMS voice over PS. In an example, the emergency service support indicator may inform the UE  100  that emergency services are supported, e.g., the UE  100  may request PDU session for emergency services. In an example, the handover restriction list and UE-AMBR may be provided to NG-RAN by the AMF  155 . 
     In an example, the UE  100  may send to the new AMF  155  a registration complete  960  message. In an example, the UE  100  may send the registration complete message  960  to the AMF  155  to 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 AMF  155  may release the signaling connection with the UE  100 . In an example, when the follow-on request is included in the registration request, the AMF  155  may not release the signaling connection after the completion of the registration procedure. In an example, if the AMF  155  is aware that some signaling is pending in the AMF  155  or between the UE  100  and the 5GC, the AMF  155  may not release the signaling connection after the completion of the registration procedure. 
     As depicted in example  FIG.  10    and  FIG.  11   , a service request procedure e.g., a UE  100  triggered service request procedure may be used by a UE  100  in CM-IDLE state to request the establishment of a secure connection to an AMF  155 .  FIG.  11    is continuation of  FIG.  10    depicting 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 UE  100  or the 5GC, and may be used when the UE  100  is 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 UE  100  in 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 AMF  155  may perform authentication. In an example, after the establishment of signaling connection to the AMF  155 , the UE  100  or network may send signaling messages, e.g. PDU session establishment from the UE  100  to a SMF  160 , via the AMF  155 . 
     In an example, for any service request, the AMF  155  may respond with a service accept message to synchronize PDU session status between the UE  100  and network. The AMF  155  may respond with a service reject message to the UE  100 , if the service request may not be accepted by the network. The service reject message may include an indication or cause code requesting the UE  100  to 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 example  FIG.  10    and  FIG.  11   , more than one UPF, e.g., old UPF  110 - 2  and PDU session Anchor PSA UPF  110 - 3  may be involved. 
     In an example, the UE  100  may send to a (R)AN  105  an AN message comprising AN parameters, mobility management, MM NAS service request  1005  (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 UE  100  may provide the list of PDU sessions to be activated when the UE  100  may re-activate the PDU session(s). The list of allowed PDU sessions may be provided by the UE  100  when 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 UE  100  may send NAS service request message towards the AMF  155  encapsulated in an RRC message to the RAN  105 . 
     In an example, if the service request may be triggered for user data, the UE  100  may 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 UE  100  may not identify any PDU session(s). If this procedure may be triggered for paging response, and/or the UE  100  may have at the same time user data to be transferred, the UE  100  may 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 UE  100 . In an example, the UE  100  may not trigger the service request procedure for a PDU session corresponding to a LADN when the UE  100  may be outside the area of availability of the LADN. The UE  100  may 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)AN  105  may send to AMF  155  an N2 Message  1010  (e.g., a service request) comprising N2 parameters, MM NAS service request, and/or the like. The AMF  155  may reject the N2 message if it may not be able to handle the service request. In an example, if NG-RAN may be used, the N2 parameters 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)AN  105  may select the AMF  155  according to the 5G-GUTI. In an example, the location information and RAT type may relate to the cell in which the UE  100  may be camping. In an example, based on the PDU session status, the AMF  155  may initiate PDU session release procedure in the network for the PDU sessions whose PDU session ID(s) may be indicated by the UE  100  as not available. 
     In an example, if the service request was not sent integrity protected or integrity protection verification failed, the AMF  155  may initiate a NAS authentication/security procedure  1015 . 
     In an example, if the UE  100  triggers the service request to establish a signaling connection, upon successful establishment of the signaling connection, the UE  100  and the network may exchange NAS signaling. 
     In an example the AMF  155  may send to the SMF  160  a PDU session update context request  1020  e.g., Nsmf_PDUSession_UpdateSMContext request comprising PDU session ID(s), Cause(s), UE  100  location information, access type, and/or the like. 
     In an example, the Nsmf_PDUSession_UpdateSMContext request may be invoked by the AMF  155  if the UE  100  may 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 SMF  160  wherein the PDU session(s) identified by the UE  100  may 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 SMF  160  wherein the current UE  100  location may be outside the area of validity for the N2 information provided by the SMF  160  during a network triggered service request procedure. The AMF  155  may not send the N2 information provided by the SMF  160  during the network triggered service request procedure. 
     In an example, the AMF  155  may determine the PDU session(s) to be activated and may send a Nsmf_PDUSession_UpdateSMContext request to SMF  160 ( 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 UE  100  may not include the PDU session for which the UE  100  was paged, the AMF  155  may notify the SMF  160  that 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 AMF  155  may notify the UE  100 . 
     In an example, if the PDU session ID may correspond to a LADN and the SMF  160  may determine that the UE  100  may be outside the area of availability of the LADN based on the UE  100  location reporting from the AMF  155 , the SMF  160  may 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 AMF  155 . In an example, if the procedure may be triggered by a network triggered service request, the SMF  160  may notify the UPF  110  that originated the data notification to discard downlink data for the PDU sessions and/or to not provide further data notification messages. The SMF  160  may respond to the AMF  155  with 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 SMF  160  may determine that the UE  100  may be outside the area of availability of the LADN based on the UE  100  location reporting from the AMF  155 , the SMF  160  may decide to (based on local policies) release the PDU session. The SMF  160  may locally release the PDU session and may inform the AMF  155  that the PDU session may be released. The SMF  160  may respond to the AMF  155  with 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 SMF  160 , based on the location info received from the AMF  155 , the SMF  160  may check the UPF  110  Selection  1025  Criteria (e.g., slice isolation requirements, slice coexistence requirements, UPF&#39;s  110  dynamic load, UPF&#39;s  110  relative static capacity among UPFs supporting the same DNN, UPF  110  location available at the SMF  160 , UE  100  location information, Capability of the UPF  110  and the functionality required for the particular UE  100  session. In an example, an appropriate UPF  110  may be selected by matching the functionality and features required for a UE  100 , 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, UE  100  subscription profile in UDM  140 , DNAI as included in the PCC rules, local operator policies, S-NSSAI, access technology being used by the UE  100 , UPF  110  logical 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 UPF  110  (or add/remove an intermediate UPF  110 ), if the UE  100  has moved out of the service area of the UPF  110  that was previously connecting to the (R)AN  105 , while maintaining the UPF(s) acting as PDU session anchor; may trigger re-establishment of the PDU session to perform relocation/reallocation of the UPF  110  acting as PDU session anchor, e.g. the UE  100  has moved out of the service area of the anchor UPF  110  which is connecting to RAN  105 . 
     In an example, the SMF  160  may send to the UPF  110  (e.g., new intermediate UPF  110 ) an N4 session establishment request  1030 . In an example, if the SMF  160  may select a new UPF  110  to act as intermediate UPF  110 - 2  for the PDU session, or if the SMF  160  may select to insert an intermediate UPF  110  for a PDU session which may not have an intermediate UPF  110 - 2 , an N4 session establishment request  1030  message may be sent to the new UPF  110 , 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 UPF  110 - 2 . 
     In an example, if a new UPF  110  is selected by the SMF  160  to replace the old (intermediate) UPF  110 - 2 , the SMF  160  may include a data forwarding indication. The data forwarding indication may indicate to the UPF  110  that a second tunnel endpoint may be reserved for buffered DL data from the old I-UPF. 
     In an example, the new UPF  110  (intermediate) may send to SMF  160  an N4 session establishment response message  1030 . In case the UPF  110  may allocate CN tunnel info, the UPF  110  may provide DL CN tunnel info for the UPF  110  acting as PDU session anchor and UL CN tunnel info (e.g., CN N3 tunnel info) to the SMF  160 . If the data forwarding indication may be received, the new (intermediate) UPF  110  acting as N3 terminating point may send DL CN tunnel info for the old (intermediate) UPF  110 - 2  to the SMF  160 . The SMF  160  may start a timer, to release the resource in the old intermediate UPF  110 - 2 . 
     In an example, if the SMF  160  may selects a new intermediate UPF  110  for the PDU session or may remove the old I-UPF  110 - 2 , the SMF  160  may send N4 session modification request message  1035  to PDU session anchor, PSA UPF  110 - 3 , providing the data forwarding indication and DL tunnel information from new intermediate UPF  110 . 
     In an example, if the new intermediate UPF  110  may be added for the PDU session, the (PSA) UPF  110 - 3  may begin to send the DL data to the new I-UPF  110  as indicated in the DL tunnel information. 
     In an example, if the service request may be triggered by the network, and the SMF  160  may remove the old I-UPF  110 - 2  and may not replace the old I-UPF  110 - 2  with the new I-UPF  110 , the SMF  160  may include the data forwarding indication in the request. The data forwarding indication may indicate to the (PSA) UPF  110 - 3  that a second tunnel endpoint may be reserved for buffered DL data from the old I-UPF  110 - 2 . In this case, the PSA UPF  110 - 3  may begin to buffer the DL data it may receive at the same time from the N6 interface. 
     In an example, the PSA UPF  110 - 3  (PSA) may send to the SMF  160  an N4 session modification response  1035 . In an example, if the data forwarding indication may be received, the PSA UPF  110 - 3  may become as N3 terminating point and may send CN DL tunnel info for the old (intermediate) UPF  110 - 2  to the SMF  160 . The SMF  160  may start a timer, to release the resource in old intermediate UPF  110 - 2  if there is one. 
     In an example, the SMF  160  may send to the old UPF  110 - 2  an N4 session modification request  1045  (e.g., may comprise new UPF  110  address, new UPF  110  DL tunnel ID, and/or the like). In an example, if the service request may be triggered by the network, and/or the SMF  160  may remove the old (intermediate) UPF  110 - 2 , the SMF  160  may send the N4 session modification request message to the old (intermediate) UPF  110 - 2 , and may provide the DL tunnel information for the buffered DL data. If the SMF  160  may allocate new I-UPF  110 , the DL tunnel information is from the new (intermediate) UPF  110  may act as N3 terminating point. If the SMF  160  may not allocate a new I-UPF  110 , the DL tunnel information may be from the new UPF  110  (PSA)  110 - 3  acting as N3 terminating point. The SMF  160  may start a timer to monitor the forwarding tunnel. In an example, the old (intermediate) UPF  110 - 2  may send N4 session modification response message to the SMF  160 . 
     In an example, if the I-UPF  110 - 2  may be relocated and forwarding tunnel was established to the new I-UPF  110 , the old (intermediate) UPF  110 - 2  may forward its buffered data to the new (intermediate) UPF  110  acting as N3 terminating point. In an example, if the old I-UPF  110 - 2  may be removed and the new I-UPF  110  may not be assigned for the PDU session and forwarding tunnel may be established to the UPF  110  (PSA)  110 - 3 , the old (intermediate) UPF  110 - 2  may forward its buffered data to the UPF  110  (PSA)  110 - 3  acting as N3 terminating point. 
     In an example, the SMF  160  may send to the AMF  155  an N11 message  1060  e.g., a Nsmf_PDUSession_UpdateSMContext response (comprising: N1 SM container (PDU session ID, PDU session re-establishment indication), N2 SM information (PDU session ID, QoS profile, CN N3 tunnel info, S-NSSAI), Cause), upon reception of the Nsmf_PDUSession_UpdateSMContext request with a cause including e.g., establishment of user plane resources. The SMF  160  may determine whether UPF  110  reallocation may be performed, based on the UE  100  location information, UPF  110  service area and operator policies. In an example, for a PDU session that the SMF  160  may determine to be served by the current UPF  110 , e.g., PDU session anchor or intermediate UPF, the SMF  160  may generate N2 SM information and may send a Nsmf_PDUSession_UpdateSMContext response  1060  to the AMF  155  to establish the user plane(s). The N2 SM information may contain information that the AMF  155  may provide to the RAN  105 . In an example, for a PDU session that the SMF  160  may determine as requiring a UPF  110  relocation for PDU session anchor UPF, the SMF  160  may reject the activation of UP of the PDU session by sending Nsmf_PDUSession_UpdateSMContext response that may contain N1 SM container to the UE  100  via the AMF  155 . The N1 SM container may include the corresponding PDU session ID and PDU session re-establishment indication. 
     Upon reception of the Namf_EventExposure_Notify from the AMF  155  to the SMF  160 , with an indication that the UE  100  is reachable, if the SMF  160  may have pending DL data, the SMF  160  may invoke the Namf_Communication_N1N2MessageTransfer service operation to the AMF  155  to establish the user plane(s) for the PDU sessions. In an example, the SMF  160  may resume sending DL data notifications to the AMF  155  in case of DL data. 
     In an example, the SMF  160  may send a message to the AMF  155  to 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 UE  100  may be outside the area of availability of the LADN, or if the AMF  155  may notify the SMF  160  that the UE  100  may be reachable for regulatory prioritized service, and the PDU session to be activated may not for a regulatory prioritized service; or if the SMF  160  may decide to perform PSA UPF  110 - 3  relocation for the requested PDU session. 
     In an example, the AMF  155  may send to the (R)AN  105  an N2 request message  1065  (e.g., N2 SM information received from SMF  160 , security context, AMF  155  signaling connection ID, handover restriction list, MM NAS service accept, list of recommended cells/TAs/NG-RAN node identifiers). In an example, the RAN  105  may store the security context, AMF  155  signaling connection Id, QoS information for the QoS flows of the PDU sessions that may be activated and N3 tunnel IDs in the UE  100  RAN  105  context. In an example, the MM NAS service accept may include PDU session status in the AMF  155 . If the activation of UP of a PDU session may be rejected by the SMF  160 , 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 UE  100  via the session Status. 
     In an example, if there are multiple PDU sessions that may involve multiple SMF  160   s , the AMF  155  may not wait for responses from all SMF  160   s  before it may send N2 SM information to the UE  100 . The AMF  155  may wait for all responses from the SMF  160   s  before it may send MM NAS service accept message to the UE  100 . 
     In an example, the AMF  155  may include at least one N2 SM information from the SMF  160  if the procedure may be triggered for PDU session user plane activation. AMF  155  may send additional N2 SM information from SMF  160   s  in separate N2 message(s) (e.g. N2 tunnel setup request), if there is any. Alternatively, if multiple SMF  160   s  may be involved, the AMF  155  may send one N2 request message to (R)AN  105  after all the Nsmf_PDUSession_UpdateSMContext response service operations from all the SMF  160   s  associated with the UE  100  may be received. In such case, the N2 request message may include the N2 SM information received in each of the Nsmf_PDUSession_UpdateSMContext response and PDU session ID to enable AMF  155  to associate responses to relevant SMF  160 . 
     In an example, if the RAN  105  (e.g., NG RAN) node may provide the list of recommended cells/TAs/NG-RAN node identifiers during the AN release procedure, the AMF  155  may include the information from the list in the N2 request. The RAN  105  may use this information to allocate the RAN  105  notification area when the RAN  105  may decide to enable RRC inactive state for the UE  100 . 
     If the AMF  155  may receive an indication, from the SMF  160  during a PDU session establishment procedure that the UE  100  may be using a PDU session related to latency sensitive services, for any of the PDU sessions established for the UE  100  and the AMF  155  has received an indication from the UE  100  that may support the CM-CONNECTED with RRC inactive state, then the AMF  155  may include the UE&#39;s RRC inactive assistance information. In an example, the AMF  155  based on network configuration, may include the UE&#39;s RRC inactive assistance information. 
     In an example, the (R)AN  105  may send to the UE  100  a message to perform RRC connection reconfiguration  1070  with the UE  100  depending 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 N2 request may include a MM NAS service accept message, the RAN  105  may forward the MM NAS service accept to the UE  100 . The UE  100  may locally delete context of PDU sessions that may not be available in 5GC. 
     In an example, if the N1 SM information may be transmitted to the UE  100  and may indicate that some PDU session(s) may be re-established, the UE  100  may 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 UE  100  may be forwarded to the RAN  105 . The RAN  105  (e.g., NG-RAN) may send the uplink data to the UPF  110  address and tunnel ID provided. 
     In an example, the (R)AN  105  may send to the AMF  155  an N2 request Ack  1105  (e.g., N2 SM 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 N2 request message may include N2 SM information(s), e.g. AN tunnel info. RAN  105  may respond N2 SM information with separate N2 message (e.g. N2 tunnel setup response). In an example, if multiple N2 SM information are included in the N2 request message, the N2 request Ack may include multiple N2 SM information and information to enable the AMF  155  to associate the responses to relevant SMF  160 . 
     In an example, the AMF  155  may send to the SMF  160  a Nsmf_PDUSession_UpdateSMContext request  1110  (N2 SM information (AN tunnel info), RAT type) per PDU session. If the AMF  155  may receive N2 SM information (one or multiple) from the RAN  105 , then the AMF  155  may forward the N2 SM information to the relevant SMF  160 . If the UE  100  time zone may change compared to the last reported UE  100  Time Zone then the AMF  155  may include the UE  100  time zone IE in the Nsmf_PDUSession_UpdateSMContext request message. 
     In an example, if dynamic PCC is deployed, the SMF  160  may initiate notification about new location information to the PCF  135  (if subscribed) by invoking an event exposure notification operation (e.g., a Nsmf_EventExposure_Notify service operation). The PCF  135  may provide updated policies by invoking a policy control update notification message  1115  (e.g., a Npcf_SMPolicyControl_UpdateNotify operation). 
     In an example, if the SMF  160  may select a new UPF  110  to act as intermediate UPF  110  for the PDU session, the SMF  160  may initiates an N4 session modification procedure  1120  to the new I-UPF  110  and may provide AN tunnel info. The downlink data from the new I-UPF  110  may be forwarded to RAN  105  and UE  100 . In an example, the UPF  110  may send to the SMF  160 , an N4 session modification response  1120 . In an example, the SMF  160  may send to the AMF  155 , a Nsmf_PDUSession_UpdateSMContext response  1140 . 
     In an example, if forwarding tunnel may be established to the new I-UPF  110  and if the timer SMF  160  set for forwarding tunnel may be expired, the SMF  160  may sends N4 session modification request  1145  to new (intermediate) UPF  110  acting as N3 terminating point to release the forwarding tunnel. In an example, the new (intermediate) UPF  110  may send to the SMF  160  an N4 session modification response  1145 . In an example, the SMF  160  may send to the PSA UPF  110 - 3  an N4 session modification request  1150 , or N4 session release request. In an example, if the SMF  160  may continue using the old UPF  110 - 2 , the SMF  160  may send an N4 session modification request  1155 , providing AN tunnel info. In an example, if the SMF  160  may select a new UPF  110  to act as intermediate UPF  110 , and the old UPF  110 - 2  may not be PSA UPF  110 - 3 , the SMF  160  may initiate resource release, after timer expires, by sending an N4 session release request (release cause) to the old intermediate UPF  110 - 2 . 
     In an example, the old intermediate UPF  110 - 2  may send to the SMF  160  an N4 session modification response or N4 session release response  1155 . The old UPF  110 - 2  may acknowledge with the N4 session modification response or N4 session release response message to confirm the modification or release of resources. The AMF  155  may 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 AMF  155  may invoke the Namf_EventExposure_Notify towards the SMF  160  if the SMF  160  had subscribed for UE  100  moving into or out of area of interest and if the UE&#39;s current location may indicate that it may be moving into or moving outside of the area of interest subscribed, or if the SMF  160  had subscribed for LADN DNN and if the UE  100  may be moving into or outside of an area where the LADN is available, or if the UE  100  may be in MICO mode and the AMF  155  had notified an SMF  160  of the UE  100  being unreachable and that SMF  160  may not send DL data notifications to the AMF  155 , and the AMF  155  may informs the SMF  160  that the UE  100  is reachable, or if the SMF  160  had subscribed for UE  100  reachability status, then the AMF  155  may notify the UE  100  reachability. 
     An example PDU session establishment procedure depicted in  FIG.  12    and  FIG.  13   . In an example embodiment, when the PDU session establishment procedure may be employed, the UE  100  may send to the AMF  155  a NAS Message  1205  (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, N1 SM container (PDU session establishment request), and/or the like. In an example, the UE  100 , 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 UE  100  may initiate the UE  100  requested PDU session establishment procedure with a request type indicating emergency request. In an example, the UE  100  may initiate the UE  100  requested PDU session establishment procedure by the transmission of the NAS message containing a PDU session establishment request within the N1 SM 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 UE  100  may be encapsulated by the AN in a N2 message towards the AMF  155  that 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 UE  100  may 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 AMF  155  may 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 RAN  105 ). In an example, the UE  100  may not trigger a PDU session establishment for a PDU session corresponding to a LADN when the UE  100  is outside the area of availability of the LADN. 
     In an example, the AMF  155  may 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 UE  100 . If the NAS message does not contain an S-NSSAI, the AMF  155  may determine a default S-NSSAI for the requested PDU session either according to the UE  100  subscription, if it may contain one default S-NSSAI, or based on operator policy. In an example, the AMF  155  may perform SMF  160  selection  1210  and select an SMF  160 . If the request type may indicate initial request or the request may be due to handover from EPS, the AMF  155  may store an association of the S-NSSAI, the PDU session ID and a SMF  160  ID. 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 AMF  155  may select the SMF  160  and may store an association of the new PDU session ID and the selected SMF  160  ID. 
     In an example, the AMF  155  may send to the SMF  160 , an N11 message  1215 , e.g., Nsmf_PDUSession_CreateSMContext request (comprising: SUPI or PEI, DNN, S-NSSAI, PDU session ID, AMF  155  ID, request type, N1 SM container (PDU session establishment request), user location information, access type, PEI, GPSI), or Nsmf_PDUSession_UpdateSMContext request (SUPI, DNN, S-NSSAI, PDU session ID, AMF  155  ID, request type, N1 SM container (PDU session establishment request), user location information, access type, RAT type, PEI). In an example, if the AMF  155  may not have an association with the SMF  160  for the PDU session ID provided by the UE  100  (e.g. when request type indicates initial request), the AMF  155  may invoke the Nsmf_PDUSession_CreateSMContext request, but if the AMF  155  already has an association with an SMF  160  for the PDU session ID provided by the UE  100  (e.g. when request type indicates existing PDU session), the AMF  155  may invoke the Nsmf_PDUSession_UpdateSMContext request. In an example, the AMF  155  ID may be the UE&#39;s GUAMI which uniquely identifies the AMF  155  serving the UE  100 . The AMF  155  may forward the PDU session ID together with the N1 SM container containing the PDU session establishment request received from the UE  100 . The AMF  155  may provide the PEI instead of the SUPI when the UE  100  has registered for emergency services without providing the SUPI. In case the UE  100  has registered for emergency services but has not been authenticated, the AMF  155  may 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 SMF  160  has not yet registered and subscription data may not be available, the SMF  160  may register with the UDM  140 , and may retrieve subscription data  1225  and 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 SMF  160  may determine that the request may be due to handover between 3GPP access and non-3GPP access or due to handover from EPS. The SMF  160  may identify the existing PDU session based on the PDU session ID. The SMF  160  may 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 AMF  155  in 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 SMF  160  may identify the existing PDU session to be released based on the old PDU session ID. 
     In an example, the SMF  160  may send to the AMF  155 , the N11 message response  1220 , e.g., either a PDU session create/update response, Nsmf_PDUSession_CreateSMContext response  1220  (cause, SM context ID or N1 SM container (PDU session reject(cause))) or a Nsmf_PDUSession_UpdateSMContext response. 
     In an example, if the SMF  160  may perform secondary authorization/authentication  1230  during the establishment of the PDU session by a DN-AAA server, the SMF  160  may select a UPF  110  and may trigger a PDU session establishment authentication/authorization. 
     In an example, if the request type may indicate initial request, the SMF  160  may select an SSC mode for the PDU session. The SMF  160  may select one or more UPFs as needed. In case of PDU type IPv4 or IPv6, the SMF  160  may allocate an IP address/prefix for the PDU session. In case of PDU type IPv6, the SMF  160  may allocate an interface identifier to the UE  100  for the UE  100  to build its link-local address. For Unstructured PDU type the SMF  160  may allocate an IPv6 prefix for the PDU session and N6 point-to-point tunneling (based on UDP/IPv6). 
     In an example, if dynamic PCC is deployed, the may SMF  160  performs PCF  135  selection  1235 . If the request type indicates existing PDU session or existing emergency PDU session, the SMF  160  may use the PCF  135  already selected for the PDU session. If dynamic PCC is not deployed, the SMF  160  may apply local policy. 
     In an example, the SMF  160  may perform a session management policy establishment procedure  1240  to establish a PDU session with the PCF  135  and may get the default PCC Rules for the PDU session. The GPSI may be included if available at the SMF  160 . If the request type in  1215  indicates existing PDU session, the SMF  160  may notify an event previously subscribed by the PCF  135  by a session management policy modification procedure and the PCF  135  may update policy information in the SMF  160 . The PCF  135  may provide authorized session-AMBR and the authorized 5QI and ARP to SMF  160 . The PCF  135  may subscribe to the IP allocation/release event in the SMF  160  (and may subscribe other events). 
     In an example, the PCF  135 , 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 in  1215  indicates initial request, the SMF  160  may select an SSC mode for the PDU session. The SMF  160  may select  1245  one or more UPFs as needed. In case of PDU type IPv4 or IPv6, the SMF  160  may allocate an IP address/prefix for the PDU session. In case of PDU type IPv6, the SMF  160  may allocate an interface identifier to the UE  100  for the UE  100  to build its link-local address. For unstructured PDU type the SMF  160  may allocate an IPv6 prefix for the PDU session and N6 point-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 SMF  160  to the UE  100  for this PDU session. 
     In an example, if the request type in  1215  is existing PDU session, the SMF  160  may maintain the same IP address/prefix that may be allocated to the UE  100  in the source network. 
     In an example, if the request type in  1215  indicates existing PDU session referring to an existing PDU session moved between 3GPP access and non-3GPP access, the SMF  160  may maintain the SSC mode of the PDU session, e.g., the current PDU session Anchor and IP address. In an example, the SMF  160  may trigger e.g. new intermediate UPF  110  insertion or allocation of a new UPF  110 . In an example, if the request type indicates emergency request, the SMF  160  may select  1245  the UPF  110  and may select SSC mode  1 . 
     In an example, the SMF  160  may perform a session management policy modification  1250  procedure to report some event to the PCF  135  that has previously subscribed. If request type is initial request and dynamic PCC is deployed and PDU type is IPv4 or IPv6, the SMF  160  may notify the PCF  135  (that has previously subscribed) with the allocated UE  100  IP address/prefix. 
     In an example, the PCF  135  may provide updated policies to the SMF  160 . The PCF  135  may provide authorized session-AMBR and the authorized 5QI and ARP to the SMF  160 . 
     In an example, if request type indicates initial request, the SMF  160  may initiate an N4 session establishment procedure  1255  with the selected UPF  110 . The SMF  160  may initiate an N4 session modification procedure with the selected UPF  110 . In an example, the SMF  160  may send an N4 session establishment/modification request  1255  to the UPF  110  and may provide packet detection, enforcement, reporting rules, and/or the like to be installed on the UPF  110  for this PDU session. If CN tunnel info is allocated by the SMF  160 , the CN tunnel info may be provided to the UPF  110 . If the selective user plane deactivation is required for this PDU session, the SMF  160  may determine the Inactivity Timer and may provide it to the UPF  110 . In an example, the UPF  110  may acknowledges by sending an N4 session establishment/modification response  1255 . If CN tunnel info is allocated by the UPF, the CN tunnel info may be provided to SMF  160 . In an example, if multiple UPFs are selected for the PDU session, the SMF  160  may initiate N4 session establishment/modification procedure  1255  with each UPF  110  of the PDU session. 
     In an example, the SMF  160  may send to the AMF  155  an Namf_Communication_N1N2MessageTransfer  1305  message (comprising PDU session ID, access type, N2 SM information (PDU session ID, QFI(s), QoS profile(s), CN tunnel info, S-NSSAI, session-AMBR, PDU session type, and/or the like), N1 SM 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 UPF  110  that terminates N3. In an example, the N2 SM information may carry information that the AMF  155  may forward to the (R)AN  105  (e.g., the CN tunnel info corresponding to the core network address of the N3 tunnel corresponding to the PDU session, one or multiple QoS profiles and the corresponding QFIs may be provided to the (R)AN  105 , the PDU session ID may be used by AN signaling with the UE  100  to indicate to the UE  100  the association between AN resources and a PDU session for the UE  100 , and/or the like). In an example, a PDU session may be associated to an S-NSSAI and a DNN. In an example, the N1 SM container may contain the PDU session establishment accept that the AMF  155  may provide to the UE  100 . In an example, multiple QoS rules and QoS profiles may be included in the PDU session establishment accept within the N1 SM and in the N2 SM information. In an example, the Namf_Communication_N1N2MessageTransfer  1305  may further comprise the PDU session ID and information allowing the AMF  155  to know which access towards the UE  100  to use. 
     In an example, the AMF  155  may send to the (R)AN  105  an N2 PDU session request  1310  (comprising N2 SM information, NAS message (PDU session ID, N1 SM container (PDU session establishment accept, and/or the like))). In an example, the AMF  155  may send the NAS message  1310  that may comprise PDU session ID and PDU session establishment accept targeted to the UE  100  and the N2 SM information received from the SMF  160  within the N2 PDU session request  1310  to the (R)AN  105 . 
     In an example, the (R)AN  105  may issue AN specific signaling exchange  1315  with the UE  100  that may be related with the information received from SMF  160 . In an example, in case of a 3GPP RAN  105 , an RRC connection reconfiguration procedure may take place with the UE  100  to establish the necessary RAN  105  resources related to the QoS Rules for the PDU session request  1310 . In an example, (R)AN  105  may allocate (R)AN  105  N3 tunnel information for the PDU session. In case of dual connectivity, the master RAN  105  node may assign some (zero or more) QFIs to be setup to a master RAN  105  node and others to the secondary RAN  105  node. The AN tunnel info may comprise a tunnel endpoint for each involved RAN  105  node, and the QFIs assigned to each tunnel endpoint. A QFI may be assigned to either the master RAN  105  node or the secondary RAN  105  node. In an example, (R)AN  105  may forward the NAS message  1310  (PDU session ID, N1 SM container (PDU session establishment accept)) to the UE  100 . The (R)AN  105  may provide the NAS message to the UE  100  if the necessary RAN  105  resources are established and the allocation of (R)AN  105  tunnel information are successful. 
     In an example, the N2 PDU session response  1320  may comprise a PDU session ID, cause, N2 SM 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 N3 tunnel corresponding to the PDU session. 
     In an example, the AMF  155  may forward the N2 SM information received from (R)AN  105  to the SMF  160  via a Nsmf_PDUSession_UpdateSMContext request  1330  (comprising: N2 SM information, request type, and/or the like). In an example, if the list of rejected QFI(s) is included in N2 SM information, the SMF  160  may release the rejected QFI(s) associated QoS profiles. 
     In an example, the SMF  160  may initiate an N4 session modification procedure  1335  with the UPF  110 . The SMF  160  may provide AN tunnel info to the UPF  110  as well as the corresponding forwarding rules. In an example, the UPF  110  may provide an N4 session modification response  1335  to the SMF  160160 . 
     In an example, the SMF  160  may send to the AMF  155  a Nsmf_PDUSession_UpdateSMContext response  1340  (Cause). In an example, the SMF  160  may subscribe to the UE  100  mobility event notification from the AMF  155  (e.g. location reporting, UE  100  moving into or out of area of interest), after this step by invoking Namf_EventExposure_Subscribe service operation. For LADN, the SMF  160  may subscribe to the UE  100  moving into or out of LADN service area event notification by providing the LADN DNN as an indicator for the area of interest. The AMF  155  may forward relevant events subscribed by the SMF  160 . 
     In an example, the SMF  160  may send to the AMF  155 , a Nsmf_PDUSession_SMContextStatusNotify (release)  1345 . In an example, if during the procedure, any time the PDU session establishment is not successful, the SMF  160  may inform the AMF  155  by invoking Nsmf_PDUSession_SMContextStatusNotify(release)  1345 . The SMF  160  may releases any N4 session(s) created, any PDU session address if allocated (e.g. IP address) and may release the association with the PCF  135 . 
     In an example, in case of PDU type IPv6, the SMF  160  may generate an IPv6 Router Advertisement  1350  and may send it to the UE  100  via N4 and the UPF  110 . 
     In an example, if the PDU session may not be established, the SMF  160  may unsubscribe  1360  to the modifications of session management subscription data for the corresponding (SUPI, DNN, S-NSSAI), using Nudm_SDM_Unsubscribe (SUPI, DNN, S-NSSAI), if the SMF  160  is no more handling a PDU session of the UE  100  for this (DNN, S-NSSAI). In an example, if the PDU session may not be established, the SMF  160  may deregister  1360  for the given PDU session using Nudm_UECM_Deregistration (SUPI, DNN, PDU session ID). 
     A satellite may be a space-borne vehicle embarking a bent pipe payload or a regenerative payload telecommunication transmitter. The satellite may be placed into a low-earth orbit (LEO) at an altitude between 300 km to 1500 km, a medium-earth orbit (MEO) at an altitude between 8000 to 20000 km, or a geostationary satellite earth orbit (GEO) at 35,786 km altitude. A satellite network may be a network or network segment that uses a space-borne vehicle to embark a transmission equipment relay node or a base station. While a terrestrial network is a network located on the surface of the earth, a non-terrestrial network (NTN) may be a network which uses a satellite as an access network, a backhaul interface network, or both. 
       FIGS.  14 A and  14 B  are examples of NTN architectures in which a satellite is used as part of a network as per embodiments of the present disclosure. 
       FIG.  14 A  shows an example NTN architecture corresponding to a transparent satellite model. The NTN architecture of  FIG.  14 A  comprises a wireless device, a satellite, an NTN gateway, a base station, a 5G core network, and a data network. In the NTN architecture of  FIG.  14 A , the satellite may behave as a remote radio unit (RRU) communicating with the NTN gateway. The NTN gateway may connect to a base station on the ground. The wireless device may transmit and receive via the satellite and the satellite may implement frequency conversion and radio frequency amplification in both the uplink and downlink directions. The satellite (an RRU in this example) may correspond to an analogue RF repeater that repeats the NR-Uu radio interface from a service link (between the satellite and the wireless device) to a feeder link (between the NTN gateway and the satellite), and vice-versa. 
       FIG.  14 B  shows an example NTN architecture regarding corresponding to a regenerative satellite model. The NTN architecture of  FIG.  14 B  comprises a wireless device, a satellite, an NTN gateway, a 5G core network, and/or the like. The satellite may regenerate signals received from earth (e.g. from a wireless device or from an NTN gateway). In an example, the satellite may behave as a base station. 
       FIG.  15    depicts earth orbits of example satellites. In an example, a low earth orbit (LEO) orbits earth with an altitude ranging from 300 km to 1500 km above the surface of the earth. An orbital period of the LEO may be between about 84 minutes and 127 minutes. In an example, mean orbital velocity needed to maintain a stable LEO may be 7.8 km/s and may be reduced with increased orbital altitude. In an example, mean orbital velocity for circular orbit of 200 km may be 7.79 km/s. In an example, mean orbital velocity for circular orbit 1500 km may be 7.12 km/s. In another example, a geostationary satellite earth orbit (GEO) orbits earth with an altitude 35,786 km above the surface of the earth. The GEO may be established at an altitude very close to 35,786 km (22,236 mi) and directly above the equator. This equates to an orbital velocity of 3.07 km/s (1.91 mi/s) and an orbital period of 1,436 minutes, which equates to almost one sidereal day (23.934461223 hours). From the perspective of a given point on the surface of the earth, the position of the LEO satellite may change, while the position of the GEO may not move. 
       FIG.  16    shows different types of non-terrestrial networks comprising low earth orbiting (LEO) satellites, medium earth orbiting (MEO) satellites, geostationary earth orbiting (GEO), unmanned aircraft system (UAS) and highly elliptical orbiting (HEO) satellites. In an example, the typical beam footprint size of the GEO satellite is 200˜1000 km. The footprint of a communications satellite may be the ground area that its transponders offer coverage and determines the satellite dish diameter required to receive each transponder&#39;s signal. The transponders may be a wireless device. 
       FIG.  17    shows examples of propagation delay corresponding to NTNs of different altitudes. The propagation delay of this example figure is one-way latency. In an example, one-way latency is an amount of time required to propagate through a telecommunication system from a terminal to the receiver (e.g. base station, eNB, gNB, RRU of a base station). In an example, for the transparent satellite model of GEO case, the round-trip propagation delay including service link (e.g. between the satellite and the wireless device) and feeder link (e.g. between the NTN gateway and the satellite) may be four times of 138.9 milliseconds (approximately 556 milliseconds). If processing time and congestion are taken into account, the round-trip delay of the GEO satellite may be more than a few seconds. In an example, terrestrial network (e.g. NR, E-UTRA, LTE) round-trip propagation delay may negligible. In an example, terrestrial network round-trip propagation delay may be less than 1 millisecond. In an example, the GEO satellite round-trip delay may be hundreds of times longer than the one of terrestrial network. 
       FIG.  18    is an example architecture of a 5G system having a 5G core network that provides service to different types of access networks as per an aspect of an embodiment of the present disclosure. The different types of access networks may include terrestrial access networks and non-terrestrial access networks. An ng-eNB may constitute a type of terrestrial access network and a gNB may constitute another type of terrestrial access network. A non-GEO (e.g. LEO) satellite may be a type of non-terrestrial access network and a GEO satellite may constitute another type of non-terrestrial access network. The 5G core network may operate multiple access networks which have different physical perspectives (e.g. latency, throughput, delay). 
       FIG.  19    depicts an architecture (left side) and coverage map (right side) of a deployment scenario in which one public land mobile network (e.g. PLMN A) provides both a non-terrestrial access network and a terrestrial access network. In an example, a wireless device may be able to access the non-terrestrial access network and the terrestrial access network. In this deployment scenario, separate NG instances (e.g. N2, N3) are handling separate access type nodes. The coverage of the non-terrestrial access network may span over the coverage of the terrestrial access network. In an example, the PLMN A is a Verizon, AT&amp;T and/or the like. In an example, Verizon may deploy a cellular access network (e.g. 4G, 5G terrestrial network) and a non-terrestrial access network. A wireless device which is a subscriber of Verizon may access to a core network via the terrestrial access network when the wireless device is in a coverage area of the terrestrial access network. In an example, urban area or suburban area may be the coverage area of the terrestrial access network. The wireless device may access the core network via the non-terrestrial access network when the wireless device is out of coverage area of the terrestrial access network. In an example, the rural area or mountain area may be out of the terrestrial access network coverage. 
       FIG.  20    depicts an architecture (left side) and coverage map (right side) of a scenario in which two different public land mobile networks (e.g. PLMN A and PLMN B) respectively provide a non-terrestrial access network and a terrestrial access network. In an example, the PLMN B is a Verizon, AT&amp;T and/or the like. In an example, the PLMN B is an Iridium communication. In an example, Verizon may have roaming agreement with non-terrestrial network operator Iridium communication. A wireless device which is subscriber of the Verizon may access Verizon terrestrial access network if the wireless device resides in the coverage of the terrestrial access network. The wireless device may roam to the non-terrestrial access network, PLMN B, if the wireless device is out of coverage of the terrestrial access network. 
     Reachability management of a wireless network system (e.g., 4G, 5G) may be responsible for detecting whether a wireless device is reachable and providing a location (e.g. access node) of the wireless device where the network can reach the wireless device. This may be done using wireless device area/location tracking and paging the wireless device. In an example, the wireless device area/location tracking may include UE registration area tracking (e.g. UE registration area update) and UE reachability tracking (e.g. UE periodic registration area update). The functionality of the reachability management may be either located at 5GC (e.g. AGM) in the case of CM-IDLE state or an access network (e.g., NG-RAN) in the case of CM-CONNECTED state. In an example, the UE registration area tracking may be done by performing a registration area update by a wireless device. 
     In an example, in the case of CM-IDLE state, the network may track a relative location of the wireless device, e.g., a location of the wireless device relative to one or more tracking areas. In an example, in the case of CM-CONNECTED state, the network may track a relative location of the wireless device, e.g., a location of the wireless device relative to one or more tracking areas, a location of the wireless device relative to one or more cells, a location of the wireless device relative to RAN areas. 
       FIG.  21    illustrates an example registration area representing as a tracking area (TA). Six cells are shown in  FIG.  21    and the cell 1 and the cell 2 both broadcast TA1. The cell 3 broadcasts TA2. The cell 4 and the cell 5 broadcast TA 3. Lastly, the cell 6 broadcasts TA4. 
     In the present example, a wireless device is initially located under the area of the cell 1 and the wireless device selects the cell 1 for camping based on cell selection/reselection criteria. In an example, if a Reference Signal Received Power (RSRP) of the cell 1 is higher than other neighbor cells (e.g. cell 2, cell 3), the wireless device may select the cell 1. The wireless device may receive a registration area 1 via the cell 1 from a network. The registration area 1 may comprise TA1 and TA2. The wireless device may not send a registration request message to update registration area if the wireless device moves inside the current registration area (e.g. registration area 1). In an example, the wireless device may move from the cell 1 to the cell 4 (via cell 2). The wireless device may determine that the wireless device has left the current registration area if the wireless device selects and camps on the cell 4. The wireless device may send a registration request message to the network in response to the determining. The network may send a registration accept message indicating a new registration area (e.g. registration area 2) in response to receiving the registration request message. The network can track the wireless device based on the registration area update. 
     A satellite navigation system may be a system that uses satellites to provide autonomous geo-spatial positioning. It allows small electronic receivers to determine their absolute location (for example, longitude, latitude, and altitude/elevation) relative to the earth with high precision (within a few centimeters to meters) using time signals transmitted along a line of sight by radio from satellites. The system may be used for providing position, navigation, or for tracking the position of something fitted with a receiver (satellite tracking). The signals may allow the electronic receiver to calculate the current local time to high precision, which allows time synchronization. 
     A satellite navigation system with global coverage may be termed a global navigation satellite system (GNSS). As of October 2018, the United States&#39; Global Positioning System (GPS) and Russia&#39;s GLONASS are fully operational GNSSs, with China&#39;s BeiDou Navigation Satellite System (BDS) and the European Union&#39;s Galileo scheduled to be fully operational by 2020. India already has functioning Indian Regional Navigation Satellite System (IRNSS) with an operational name of NAVIC, it is an autonomous regional satellite navigation system that provides accurate real-time positioning and timing services. In an example, each global GNSS may be used individually or in combination with others. When used in combination, the effective number of navigation satellite signals would be increased. The global coverage for each system is generally achieved by a satellite constellation of 18-30 medium Earth orbit (MEO) satellites spread between several orbital planes. The actual systems may vary, and use orbital inclinations of &gt;50° and orbital periods of roughly twelve hours (at an altitude of about 20,000 kilometers or 12,000 miles). 
     In an example, sidelink may comprise sidelink discovery, sidelink communication and V2X sidelink communication between wireless devices. Sidelink uses uplink resources (e.g. the resource from a wireless device to an access network) and physical channel structure similar to uplink transmissions. 
     In order to assist an access network to provide sidelink resources, the wireless device in RRC_CONNECTED may report geographical location information (e.g. a zone identity) to the access network. The access network can configure the wireless device to report the complete wireless device geographical location information based on periodic reporting via a measurement report signaling. In an example, a geographical zone configuration parameter may be provided by an access network or pre-configured in a wireless device. When the geographical zone configuration parameter is (pre)configured, the world (e.g. earth) is divided into geographical zones using a single fixed reference point (e.g. geographical coordinates (0, 0)), a length of the zone and a width of the zone. In an example, the wireless device may determine a zone identity (e.g. zone id) by means of modulo operation using the length and the width of zone, number of zones in length, number of zones in width, the single fixed reference point and the geographical absolute coordinates of the wireless device&#39;s current location. The geographical zone configuration parameter may comprise the length and the width of zone, number of zones in length and number of zones in width. The zone configuration information may be provided by the access network when the wireless device is in coverage of the access network. The zone configuration information may be pre-configured when the wireless device is out of coverage of the access network. The zone is configurable for both in coverage and out of coverage. 
       FIG.  22 A  shows an example formulate of zone identity based on the geographical zone configuration parameter. ‘L’ is the value of zone length and may comprise any suitable distance, for example, 5 meters, 10 meters, 50 meters, 100 meters, 200 meters, 500 meters and/or the like. ‘W’ is the value of zone width and may comprise any suitable distance, for example, 5 meters, 10 meters, 50 meters, 100 meters, 200 meters, 500 meters and/or the like. ‘Nx’ indicates the total number of zones that are configured with respect to longitude and may comprise any suitable number, for example, 1, 2, 3, 4 and/or the like. The ‘Ny’ indicates the total number of zones that is configured with respect to latitude and may comprise any suitable number, for example, 1, 2, 3, 4 and/or the like. ‘x’ is the geodesic distance in longitude between the current location of the wireless device and geographical coordinate (0, 0). ‘y’ is the geodesic distance in latitude between the current location of the wireless device a geographical coordinate (0, 0).  FIG.  22 B  shows an example zone identity numbering based on the formulae given in  FIG.  22 A  for the case that the ‘Nx’ is 3 and ‘Ny’ is 3. In an example, the zone identity may not be identical in whole geographical area. In an example, the zone identity may be identical in a limited area and the zone identity may be repeated as the modulo value to the number of the ‘Nx’ and the ‘Ny’. 
     A geographical coordinate may be represented as an ellipsoid point, e.g., a point on the surface of an ellipsoid. The ellipsoid point may comprise a latitude, a longitude, a height and/or the like. In practice, such a description may be used to refer to a point on Earth&#39;s surface, or close to Earth&#39;s surface.  FIG.  23 A  illustrates a point on the surface of the ellipsoid and its co-ordinates. The latitude may be the angle between the equatorial plane and the perpendicular to the plane tangent to the ellipsoid surface at the point. Positive latitudes may correspond to the North hemisphere. The longitude may be the angle between the half-plane determined by the Greenwich meridian and the half-plane defined by the point and the polar axis, measured Eastward.  FIG.  23 B  describes a coding of an ellipsoid point comprising S, degrees of latitude, degrees of longitude. The S is a sign of the latitude indicating, for example, north or south. 
     In an example, determination/measurement of the ellipsoid point by a wireless device may be uncertain/inaccurate. In an example, the wireless device may report the ellipsoid point where the wireless device locates as a shape indicating a point with uncertainty. There are a number of different shapes for the ellipsoid point and may comprise an ellipsoid point, an ellipsoid point with uncertainty circle, an ellipsoid point with uncertainty ellipse, a polygon, ellipsoid point with altitude, an ellipsoid point with altitude and uncertainty ellipsoid, an ellipsoid Arc, an high accuracy ellipsoid point with uncertainty ellipse.  FIG.  24 A  illustrates an ellipsoid point with uncertainty circle. The “ellipsoid point with uncertainty circle” may be characterized by the co-ordinates of an ellipsoid point (the origin) and a distance r. It describes formally the set of points on the ellipsoid which are at a distance from the origin less than or equal to r, the distance being the geodesic distance over the ellipsoid, e.g., the minimum length of a path staying on the ellipsoid and joining the two points.  FIG.  24 B  describes a coding of an ellipsoid point with uncertainty circle comprising degrees of latitude, degrees of longitude, a distance. The distance is the r of the  FIG.  24 A . 
     The earth (e.g., world) may comprise 60 Universal Transverse Mercator (UTM) zones. The UTM system may be a horizontal position representation. In an example, the UTM may treat the earth as a perfect ellipsoid. The UTM coordinate system may divide the earth into 60 UTM zones each 6 degrees of longitude wide as described in  FIG.  25   . The UTM zones may extend from a latitude of 80° S to 84° N. In the polar regions the Universal Polar Stereographic (UPS) grid system may be used. There may be a few exceptions to zone width in Northern Europe to keep small countries in a single zone. The UTM zones may be numbered 1 through 60, starting at the international date line, longitude 180°, and proceeding east. Zone 1 may extend from 180° W to 174° W and may be centered on 177° W. 
     In an example, each UTM zone may be divided into horizontal latitude bands spanning 8 degrees of latitude as described in  FIG.  26   . These latitude bands may be lettered, south to north, beginning at 80° S with the letter C and ending with the letter X at 84° N. The letters I and O are skipped to avoid confusion with the numbers one and zero. The band lettered X spans 12° of latitude. In the  FIG.  26   , a single UTM zone measure about 20,000 km tall and about 700 km wide.  FIG.  26    has been compressed in the vertical axis by about 15X. 
     In an example, a combination of the UTM zone and the latitude band may define a grid zone. The UTM zone may be written first, followed by the latitude band. For example, a position of Washington, D.C. area may find itself in UTM zone 18 and latitude band “S”, thus the full grid zone reference may be “18S”. In an example, the grid zone may be a basic grid zone. 
     In an example, the grid zone may be scaled more smaller granularity area than the basic grid zone (e.g., diving the earth into 60 zones and the latitude band spanning as 8 degrees of latitude). The UTM coordinate system may divide the earth into higher number of zones than 60 (e.g., 120, 240, 360). In an example, the latitude band may span lower degrees of latitude (e.g. 1 degree, 2 degree) than 8 degrees. A size of the grid zone with higher number of zones than 60 and the lower degrees of latitude may be smaller in size. 
     In an example embodiment, a wireless device may employ non-terrestrial networks (NTNs) (for example, satellites, drones, etc.) to communicate with a network. The NTNs may be used for communication in addition, or as an alternative, to terrestrial network (TNs) (for example, 4G or 5G systems, WiFi, etc.). In TNs, the network may track a location (e.g., relative location) of the wireless device, e.g., a location of the wireless device relative to one or more tracking areas. The tracking areas may be determined by the network, a cell, and/or the like. The wireless device may register with the network based on the tracking areas. As an example, the wireless device may register with the TN in tracking area #1 and adopt tracking area #1 as its registration area. If the wireless device moves from tracking area #1 to tracking area #2 (as determined based on, for example, cell measurements), it will re-register with the TN via one or more cells in tracking area #2, and adopt tracking area #2 as its registration area. The TN may be kept aware of the relative location of the wireless device relative to the cell-based tracking areas defined by the TN. NTNs may operate outside the cell-based framework. 
     Existing technologies may not be efficient for the network to track location of the wireless device. In existing technologies (e.g., 5G systems) a TN may track a relative location of a wireless device relative to network-defined tracking areas. The TN (e.g., an AMF of a 3GPP or 5G system) may send a tracking area identity (TAI) list to a wireless device when the wireless device registers with the AMF. A tracking area in the TAI list may be defined with respect to one or more cell coverage areas of one or more TN entities. The TAI of a tracking area may be configured by a service operator and broadcast within the tracking area. If the network needs to communicate with the wireless device (e.g., if the network has data for the wireless device), the network may page the wireless device using the one or more cells associated with the wireless device&#39;s current TAI list. When the wireless device moves to a cell that is not in the TAI list, the wireless device may send a registration request message to the TN. In response to receiving the registration request message, the TN may send a registration accept message that includes a new TAI list. The TN tracks the location of the wireless device relative to the network-defined tracking areas so that the wireless device is reachable by the TN. 
     The position of TN entities may be fixed. If the wireless device does not move, the tracking area of the wireless device may not change, and the wireless device may not send a registration request message for a tracking area update. NTN entities may not have a fixed position. In an example, a low earth orbit (LEO)-type NTN entity may move with respect to a wireless device, even when the wireless device is stationary. For a moving access network, existing cell-based tracking may result in excessive signaling and power consumption. The stationary wireless device may frequently exit the coverage area of the moving access network, that may require frequent transmission of registration update messages. For wireless devices connecting to moving access networks, an improved registration area tracking mechanism is needed to increase resource utilization efficiency and reduce power consumption. 
     In an example embodiment, a network may provide a geographical zone configuration parameter to a wireless device. A geographical zone may be defined by an absolute location with respect to an objective coordinate system, for example, a coordinate system that is not defined by an access network. The objective coordinate system may be the earth, in which case the absolute location may be an absolute geographical location. The absolute location of the wireless device may be expressed in terms of, for example: latitude, longitude, and/or altitude (also referred to as elevation); polar coordinates; and/or any other suitable values. The absolute location may be tracked by, for example: receiving positioning signals; gathering data from accelerometers and/or gyroscopes; and/or using any other suitable positioning technology. 
     The geographical zone may be used as the registration area of the wireless device. By contrast to other existing types of registration area, e.g., the tracking areas defined in 5G systems, the geographical zone may be different from network-defined cell coverage areas. In an example embodiment, the wireless device may determine its absolute geographical location and identify a geographical zone corresponding to that absolute geographical location. The wireless device may inform the network of its registration area by sending a first registration request message indicating a first geographical zone identity of the geographical zone. In an example, the wireless device may move from the first geographical zone to a second geographical zone. The wireless device may determine that the wireless device has left the first geographical zone (and/or entered the second geographical zone) based on the absolute location of the wireless device. Implementation of an example embodiment may increase radio resource utilization efficiency by reducing unnecessary registration requests and power consumption of the wireless device. 
       FIG.  27    illustrates an example embodiment of present disclosure. As depicted in  FIG.  27   , a wireless device may perform a registration area update when one cell comprises multiple geographical zones.  FIG.  27    comprises 6 geographical zones (e.g. from zone 1 to zone 6) and 1 cell. A wireless device may be located under the area of the cell 1. In an example, a reference signal received power (RSRP) of cell 1 may be higher than other neighbor cells (e.g. cell 2, cell 3). The wireless device may camp on cell 1 based on cell reselection criteria. Cell 1 may broadcast tracking area (TA) 1 and a relative location of the wireless device may be TA 1. The wireless device may determine a first geographical location of the wireless device based on geographical coordinates. The wireless device may identify a first geographical zone identity (e.g. geographical zone identity 1) based on the first geographical location and a geographical zone configuration parameter. The wireless device may receive the geographical zone configuration parameter from a network (e.g., access network, core network). 
     The network may comprise a non-terrestrial network (NTN) type access network (radio access network). In an example, the NTN type access network may comprise a low earth orbit (LEO) satellite type, a medium earth orbit (MEO) satellite type, a geostationary earth orbit (GEO) satellite type, an unmanned aircraft system (UAS) platform type, a high elliptical orbit (HEO) platform type, and/or the like. In an example, the access network may be a moving access network. 
     The wireless device may send a first registration request message comprising the first geographical zone identity (e.g. geographical zone identity 1) to inform a registration area of the wireless device. The network may send a first registration accept message indicating a successful registration area update in response to receiving the first registration request message. The network may use the first geographical zone identity as a registration area of the wireless device. The wireless device may determine/detect that the wireless device has left the area of the first geographical zone identity and may enter a second geographical location. The second geographical area/location may be still under the area of cell 1. In an example, the wireless device may send a registration request message to indicate a change of registration area while the wireless device locates in a same tracking area of the access network. The wireless device may identify a second geographical zone identity (e.g., geographical zone identity 2) of the second geographical location based on the geographical coordinates of the second geographical location and the zone configuration parameter. The wireless device may send a second registration request message indicating a change of a registration area in response to the determination. The second registration request message may comprise the second geographical zone identity (e.g., geographical zone identity 2). The network may send a second registration accept message indicating a successful registration area update in response to receiving the first registration request message. The network may use the second geographical zone identity as a registration area of the wireless device. 
       FIG.  28    illustrates an example embodiment of the present disclosure of how a wireless device performs a registration area update when one geographical zone comprises multiple cells.  FIG.  28    comprises one zone (e.g. zone 1) and two cells (e.g. cell 1, cell 2). The zone is illustrated as a rectangle and the two cells are illustrated as a circle. A wireless device may be in a first geographical location. In an example, the first geographical location may be cell 1 as a relative location of an access network. The first geographical location may be zone 1 as an absolute location based on geographical coordinates. The wireless device may camp on cell 1 based on cell reselection criteria when the wireless device is located in the first geographical location. Cell 1 may broadcast TA 1. The wireless device may identify a first geographical zone identity (e.g. geographical zone identity 1) based on the first geographical location and a geographical zone configuration parameter. The wireless device may receive the geographical zone configuration parameter from a network (e.g. access network, core network). The wireless device may send a first registration request message comprising the first geographical zone identity (e.g. geographical zone identity 1). The network may send a first registration accept message indicating a successful registration area update in response to receiving the first registration request message. The network may use the first geographical zone identity as a registration area of the wireless. Sometime later, the wireless device may move to a location close to a cell 2. In an example, a measured RSRP of the cell 2 may be higher than a measured RSRP of the cell 1. In an example, the wireless device may determine to reselect the cell 2 based on the measured RSRP value of the cell 1 and the measured RSRP value of the cell 2. The wireless device may camp on the cell 1 in response to the determination. The cell 2 may broadcast a TA 2. The wireless device may not perform a registration request procedure to indicate a change of the tracking area (e.g., from TA 1 to TA 2) in response to changing the camped cell (e.g. tracking area(s)). 
       FIG.  29    illustrates an example embodiment of present disclosure on procedure for a geographical zone-based registration area update. In an example, a wireless device may be turned on or may enter a coverage area of a network. The network may comprise a non-terrestrial network (NTN) type access network. In an example, the NTN type access network may comprise a low earth orbit (LEO) satellite type, a medium earth orbit (MEO) satellite type, a geostationary earth orbit (GEO) satellite type, an unmanned aircraft system (UAS) platform type, a high elliptical orbit (HEO) platform type, and/or the like. In an example, the access network may be a moving access network. 
     The wireless device may determine a registration area update type to register a core network (e.g., AMF) via the access network. The registration area update type may comprise a cell-based tracking type, a geographical zone-based tracking type, and/or the like. The cell-based tracking type may be a registration area update type based on tracking areas which are broadcast by an access network as explained in  FIG.  21   . The cell-based tracking type may be a registration area update type based on relative location related to an access network. The geographical zone-based tracking type may be a registration area update type based on a geographical zone identity with respect to an objective coordinate system. In an example, the objective coordinate system may be a planet (e.g., the earth). The wireless device may determine the geographical zone identity based on an absolute geographical coordinate of the wireless device and a geographical zone configuration parameter. 
     In an example implementation, a geographical zone configuration parameter may comprise a length and a width of zone, number of zones in length and number of zones in width as explained in  FIGS.  22 A and  22 B . ‘Nx’ indicates the total number of zones that are configured with respect to longitude. In an example, ‘Nx’ may be a larger value than ‘4’. ‘Ny’ indicates the total number of zones that are configured with respect to latitude. In an example, ‘Ny’ may be a larger value than ‘4’. The geographical zone identity based on  FIG.  22 A  may not be globally unique. (e.g., the geographical zone identity ‘10’ may be repeated in this earth so the geographical zone identity may not be identical between a wireless and a network (e.g., AMF)). The network may set/select the value ‘Nx’ and ‘Ny’ as large value to uniquely identity the geographical zone based on the geographical zone identity in a serving area of the network. This example implementation may be efficient regarding the size of the geographical zone configuration parameter. The geographical zone identity may not be globally identical. The geographical zone identity of this example implementation is a numeric number. The wireless device may determine a geographical zone identity of an area where the wireless device locates (e.g., current absolute coordinates). 
     In an example implementation, a geographical zone configuration parameter may comprise a basic Universal Transverse Mercator (UTM), a UTM with a granularity parameter, and/or the like. If the geographical zone configuration parameter indicates the basic UTM, the geographical zone identity may comprise a UTM zone (e.g. 1 to 60) and a latitude band (e.g. X, W, V, U, . . . ). The granularity parameter may comprise a value of degrees for longitude wide, a value of degrees for latitude wide, and/or the like. In an example, the UTM coordinate system may divide the earth into 360 UTM zones instead of 60 UTM zones in response to the value of degrees for longitude wide being 1 degree. If a network operator wants to maintain a registration area of a wireless device smaller than the zone size of the basic UTM, the network operator may provide the granularity parameter. The geographical zone identity of this example may a combination of the UTM zone and the latitude band. The geographical zone identity of this example may be globally unique, and a size of the geographical zone configuration parameter is small. 
     In an example implementation, a geographical zone configuration parameter may be geographical mapping information between a geographical region (e.g. country, state, city) and a geographical zone identity (e.g. numeric number). In an example, one or more states of the United States may be mapped to one or more zone identities (e.g. a geographical zone identity of Virginia is ‘1’, a geographical zone identity of Maryland is ‘2), and/or the like). In an example, the geographical zone configuration parameter may be a mapping information between a geographical region and a geographical zone identity in hierarchical manner. In an example, the geographical zone identity may comprise one or more values/parameters (e.g., numeric, alphanumeric, a string of characters, and/or the like). In an example, a first numeric value/parameter may indicate a country, a second numeric value/parameter may indicate a state, a third numeric value/parameter may indicate a county. In an example, the geographical mapping information may pre-configured in wireless device. In an example, the network operator may provide the geographical mapping information when the wireless device connecting to the network. The geographical zone configuration parameter may indicate hierarchical level of the zone. In an example, level 1 may indicate an identification level of a zone in continental level (e.g. Europe, North America, and/or the like). In an example, level 2 may indicate an identification level of a zone in a country or a state inside of the country. 
     In an example implementation, the geographical zone configuration parameter may be same/common to wireless devices accessing a network (e.g., 5G system). The geographical zone configuration parameter which is common to wireless devices may be a common geographical zone configuration parameter. An access network may broadcast the common geographical zone configuration parameter. 
     In an example implementation, the geographical zone configuration parameter may be dedicated to a wireless device. The geographical zone configuration parameter which is dedicated to a specific wireless device may be a dedicated geographical zone configuration parameter. A wireless device may use the common geographical zone configuration parameter if the wireless device does not have a valid dedicated geographical zone configuration parameter. If the wireless device receives a dedicated geographical zone configuration parameter from a network (e.g., access network, core network (e.g., AMF)), the wireless device may use the dedicated geographical zone configuration parameter. The network/service operator may determine/provide the dedicated geographical zone configuration parameter based on a speed of a wireless device, a mobility pattern, a subscribed service area (e.g. United States, Global), capabilities of the wireless device and/or the like. If a speed of the wireless device is low (e.g., moving slowly), the network/service operator may provide a dedicated geographical zone configuration parameter comprising smaller size of zone grid. 
     The wireless device may determine a registration area update type based on a geographical location capability of the wireless device, a geographical zone configuration parameter, and/or the like. In an example, if the wireless device is capable of GNSS, the wireless device may select/determine a registration area update type as a geographical zone-based type. In an example, if the wireless device has a valid geographical zone configuration parameter, the wireless device may select/determine a registration area update type as a geographical zone-based type. The wireless device may determine a first geographical zone identity based on the valid geographical zone configuration parameter and a first geographical location. The wireless device may send a first registration request message to an AMF via an access network indicating the first geographical zone identity. The first registration request message may comprise a registration type, a UE identity (e.g., SUCI, 5G-GUTI), the location of the UE (e.g., last visited TAI), requested NSSAI, UE mobility management context information, information for the MICO mode usage, a registration area update type, a geographical zone identity, and/or the like. In an example, the registration type may indicate a mobility registration. In an example, the geographical zone identity may be the first geographical zone identity. In an example, the registration area update type may be a geographical zone-based type. 
     In an example, the registration request message may further comprise a speed of the wireless device, geographical location information of the wireless device, a tracking area code, and/or the like. The speed of the wireless device may be an average speed of the wireless device. The network may use the speed of the wireless device to determine a dedicated geographical zone configuration parameter. The geographical location information of the wireless device may be an absolute geographical coordinate of the wireless device. In an example, the wireless device may code the absolute geographical coordinates as explained in  FIGS.  23 A and  23 B  and in  FIGS.  24 A and  24 B . The network may use the geographical location information for paging or for determining the dedicated geographical zone configuration parameter. The network may use the tracking area code to escalate a paging area for paging retransmission. 
     The AMF may send a subscription information query message to a UDM in response to receiving the registration request message. The UDM may send a subscription information query response message to the AMF in response to receiving the subscription information query message. The subscription information query response message may comprise a recommended registration area update type, a speed of the wireless device, subscribed regions of the wireless device, an authorization information of the geographical zone-based tracking type, and/or the like. If the authorization information of the geographical zone-based tracking type does not allow the use of the geographical zone-based tracking, the AMF may send a registration accept message indicating a use of a cell-based tracking type. If the recommended registration area type indicates a use of the geographical zone-based tracking, the AMF may send a registration accept message comprising the first geographical zone identity, a tracking type indicator indicating a use of the geographical zone-based tracking type, and/or the like. In an example, the AMF may determine a dedicated geographical zone configuration parameter based on the received subscription information from the UDM, additional information from network function (e.g., PCF, NEF), O&amp;M information, local policy and/or the like. If the AMF determines to use a cell-based tracking type for the wireless device, a registration area may comprise a list of tracking area identities. If the AMF determines to use a geographical zone-based tracking type for the wireless device, a registration area may comprise the first geographical zone identity. 
     The AMF may send a registration accept message to the wireless device in response to receiving the registration request message and determining of the parameters for the registration area update. In an example, the registration accept message may comprise 5G-GUTI, the registration area, a periodic registration area update time value, a MICO mode indication, confirmed registration update type, the dedicated geographical zone configuration parameter, and/or the like. 
     The wireless device may determine a registration area update type for the next registration area update based on the confirmed registration area update type by the network. If the wireless device receives a dedicated geographical zone configuration parameter, the wireless device may update the geographical zone configuration parameter as the dedicated geographical zone configuration parameter. If a geographical zone identity of the wireless device is changed based on the updated dedicated geographical zone configuration parameter, the wireless device may indicate a change of the geographical zone identity with the AMF. In an example, the wireless device may send a registration request message comprising the changed geographical zone identity to the AMF. 
     The wireless device and the AMF may set an area of the first zone identity as a registration area of the wireless device. 
     In an example, the wireless device may move to a second geographical location as explained in  FIG.  27   . The wireless device may determine that the wireless device has left an area of the first zone identity based on the second geographical location. The wireless device may determine a second zone identity based on the valid geographical zone configuration parameter and the second geographical location. The wireless device may send a second registration request message to an AMF via an access network indicating the second geographical zone identity in response to leaving the area of the first zone identity. The AMF may send a second registration accept message in response to receiving the second registration request message. The wireless device and the AMF may set an area of the second zone identity as a registration area of the wireless device. 
       FIG.  30    illustrates an example procedure for a serving access network information exchange. In an example, an access network may be a moving access network. The access network comprises a non-terrestrial network (NTN) type access network. In an example, the NTN type access network may comprise a low earth orbit (LEO) satellite type, a medium earth orbit (MEO) satellite type, a geostationary earth orbit (GEO) satellite type, an unmanned aircraft system (UAS) platform type, a high elliptical orbit (HEO) platform type, and/or the like. In an example, the access network may be a non-GEO type access network and may comprise the LEO type, MEO type, UAS type, and/or HEO type. The non-GEO type access networks (e.g., satellite) orbits may move with high speed relative to a fixed position on earth, may result in a change of serving access network for a fixed position (e.g., geographical location). The serving access network information may comprise a list of access network(s), serving geographical area information with time information for each access network, and/or the like. In an example, the list of access network(s) may be a list of IP address of each access network(s). In an example, the list of access network(s) may be a list of unique identifiers of each access networks which are connected to an AMF. The serving geographical area information with time information may exist for each access network. The serving geographical area information may comprise a region (e.g. country, state, city), a combination of a center of area (e.g., geographical coordinates) and the radius of the area, a combination of a center of area (e.g., geographical coordinates) and a width and a length, and/or the like. The time information may be a date or a period with a date, a time interval, date interval, and/or the like. A network function (e.g. NEF, application server, PCR) may send an information update message comprising the serving access network information to the AMF. The information update message may be for a wireless device. In an example implementation, the information update message may be for wireless device(s) served by the AMF. The AMF may send an acknowledgement to the network function in response to receiving the serving access network information. 
       FIG.  31    illustrates an example paging procedure of this present disclosure. The wireless device and the AMF may perform a registration area update procedure for a geographical zone-based type as illustrated in  FIG.  29   . The AMF may receive serving access network information as illustrated in  FIG.  30   . The wireless device may be in RRC-IDLE state. 
     In an example, a network function (e.g., SMF, PCF, NEF) may send a N1N2 transfer message requesting a connection setup with a wireless device. The AMF may determine to page the wireless device if there is no dedicated connection with the wireless device. The AMF may select one or more access network nodes based on the serving access network information and a registration area of the wireless device, a location information (e.g., last/recent location) of the wireless device, present time and/or the like. In an example, the AMF may select one or more access network(s) if the one or more access network(s) serves the registration area of the wireless device. In an example, the AMF may receive the N1N2 transfer message at 12:00 PM and the registration area of the wireless device may be Washington, D.C. The AMF may select one or more access networks (e.g., satellite) which serve the area of Washington, D.C. at 12:00 PM based on the serving access network information. The serving access network information may be configured by a service operator. When selecting access network(s) for paging a wireless device, the selecting may be based on the serving access network information, the registration area of the wireless device (or a most recent location thereof), and the timing at which the N1N2 transfer message is received from the network. 
     The AMF may send a N2 paging message to the selected one or more access networks(s) to page the wireless device. The N2 paging message may comprise a paging identity (e.g. S-TMSI) of the paged wireless device and zone information for which the paged wireless device is expected to be located. In an example, the N2 paging message may further comprise a last/recent/latest location of the wireless device. The last location may comprise an absolute geographical coordinates as depicted in  FIG.  23 A  and  FIG.  23 B  or  FIG.  24 A  and  FIG.  24 B . The zone information may comprise a geographical zone identity of the wireless device. The geographical zone identity may comprise a numeric value/parameter as depicted in  FIG.  22 A , a combination of the UTM zone and the latitude band, a numeric value/parameter indicating a geographical region, and/or the like. 
     The access network may determine an area for a radio resource control (RRC) paging based on the zone information, the last location, and/or the like. In an example, the area of the zone information (e.g., geographical zone identity) may be part of the serving area of the access network. The access network may determine one or more cells among the servicing cells which is overlapped with the area of the zone information. In an example implementation, the access network may determine specific beams of a cell for the paging area (e.g., the cell area is larger than the area of the zone information). In this case, an access network may send an RRC paging message for the wireless device in specific beams (e.g., beam area which is overlapped with the area of the zone information) and the access network does not include the paging identity of the wireless device in every beam in the cell. Therefore, this present disclosure may increase a paging resource efficiency. The access network may send the RRC paging message in the determined paging area. 
     The wireless device may send a service request message to the AMF requesting a connection setup with the network in response to receiving the paging message for the wireless device. The AMF may retransmit a N2 paging message if there is no response from the wireless device in operator defined time period. The AMF may include a list of tracking area identities to the N2 paging message for the retransmission. The access network may use the tracking area if the tracking area identity is included in the N2 paging message. 
       FIG.  32    shows an example flow chart of a present disclosure that a wireless device how to select a registration area update type. In an example, the wireless device may access to an access network. In an example, the access network may be a moving access network (e.g., LEO, MEO, GEO type satellite). If the access network is not a moving access network, the wireless device may select a cell-based tracking type for the registration area update type. If the access network is a moving access network, the wireless device may determine a capability of positioning measurement. In an example, the wireless device may not support a positioning measurement (e.g. GNSS). In an example, the wireless device may not measure a positioning (e.g. an absolute geographical coordinates) of the wireless device if the wireless device locates inside of a building. If the wireless device cannot measure an absolute geographical positioning of the wireless device, the wireless device may select a cell-based tracking type for the registration area update type. If the wireless device is capable of the positioning measurement, the wireless device may check whether the wireless device has a valid geographical zone configuration parameter. The wireless device may receive a common geographical zone configuration parameter from the access network. The wireless device may receive a dedicated geographical zone configuration parameter that the valid time is not expired. If the wireless device has a valid geographical zone configuration parameter, the wireless device may select a geographical zone-based tracking type for the registration area update type. 
       FIG.  33    shows an example flow chart of a determination by an AMF of an access network for N2 paging message delivery. In an example, the AMF may determine to page a wireless device. The AMF may determine to page the wireless device in response to receiving a connection request message from a network function (e.g., SMF, PCF, NEF, and/or the like) and the wireless device being in RRC-IDLE/CM-IDLE state. The connection request message may be N1N2 transfer message or Namf_Communication_N1N2MessageTransfer message. If the AMF determines to page a wireless device, the AMF may select/determine one or more access network(s) which serve a registration area of the wireless device. The registration area of the wireless device which is stored in the AMF may comprise a list of tracking area identities, an absolute geographical region (e.g., a zone identity), and/or the like. The absolute geographical region may be a geographical zone identity. If the registration area comprises a list of tracking area identities, the AMF select/determine an access network node(s) which serves the relative area based on a list of tracking area identities in the registration area. If the registration area comprises an absolute geographical region (e.g., zone identity), the AMF may select/determine an access network node(s) which serves the absolute geographical region at a present time based on a serving access network information. In the case of, for example, moving access networks, the access network node that serves a particular geographical region at the present time may be different from the access network node that serves that particular geographical region at an earlier or later time. The serving access network information may provide the data required for determining which access network node serves a geographical region at any given time. If the AMF selects/determines one or more access network(s), the AMF may send an N2 paging message to the selected one or more access network(s). If AMF receives a service request message from the wireless device via a serving access network, the AMF may send a UE contest setup request message to the serving access network. 
     In an example, the access network may receive a N2 paging message from an AMF to page a wireless device. The N2 paging message may comprise zone information, one or more tracking area identities, a dedicated geographical zone configuration parameter and/or the like. If the N2 paging message comprises zone information (e.g., a geographical zone identity), the access network may determine a geographical region based on the zone information (e.g., a geographical zone identity) and a geographical zone configuration parameter (e.g., a geographical zone configuration parameter which is locally stored in the access network). If the N2 paging message comprises a dedicated geographical zone configuration parameter, the access network may determine a geographical region based on the zone information (e.g., a geographical zone identity) and the dedicated geographical zone configuration parameter. In an example, the geographical region may be smaller than an area of one cell of the access network. If the geographical region is smaller than an area of one cell of the access network, the access network may select/determine one or more beams(s) of the cell in which is overlapped with the geographical region at present time. If the geographical region is equal or larger than an area of one cell of the access network, the access network may select/determine one or more cells(s) in which is overlapped with the geographical region at present time. The access network may send an RRC paging message to the selected/determined cell(s) or beams(s). 
     In an example, a wireless device may receive from a network, a geographical zone configuration parameter comprising a length and a width of a one zone. The wireless device may determine a first zone identity of the wireless device based on the geographical zone configuration parameter and a first geographical location. The wireless device may send a first registration request message indicating the first zone identity to the AMF, in response to the determining. 
     In an example, the wireless device may determine that the wireless device has left an area of the first zone identity based on a second geographical location, for example, a determination that the current absolute location of the wireless device does not correspond to the area of the first zone identity. The wireless device may send a second registration request message indicating a second zone identity to the AMF. The second zone identity may be selected based on a correspondence to the current absolute location of the wireless device. 
     In an example, the network may be an access network/base station. The access network may broadcast the geographical zone configuration parameter. The network may be a server which controls a regional map of a service provider. 
     In an example, the geographical zone configuration parameter may be preconfigured in the wireless device by the service provider. In an example, the geographical zone configuration parameter may comprise a length of zone, a width of zone, number of zones in length, number of zones in width, and/or the like. The geographical zone configuration parameter may further comprise a height and number of zones in height. In an example, the geographical zone configuration parameter may comprise an indication indicating universal transverse mercator (UTM), a granularity parameter, and/or the like. In an example, the geographical zone configuration parameter may comprise geographical mapping information between a geographical region and a geographical zone identity. 
     In an example, the second zone identity may be based on the second geographical location and the zone configuration parameter. 
     In an example, the first registration request message further may comprise at least one of a tracking area identity of a serving cell, the first geographical location, a time stamp of the first geographical location, and/or the like. 
     In an example, the first and second geographical location may comprise at least one of a latitude and a longitude of the wireless device, a latitude, a longitude, and an altitude of the wireless device, and/or the like. 
     In an example, the second registration request message may further comprise at least one of a tracking area identity of a serving cell, the second geographical location, a time stamp of the second geographical location. 
     In an example, the wireless device may support a global navigation satellite system (GNSS). The wireless device may support a non-terrestrial network communication. 
     In an example, the network may comprise a non-terrestrial network (NTN) type access network. The NTN type access network comprises at least one of, a low earth orbit (LEO) satellite type, a medium earth orbit (MEO) satellite type, a geostationary earth orbit (GEO) satellite type, an unmanned aircraft system (UAS) platform type, a high elliptical orbit (HEO) platform type, and/or the like. 
     In an example, the access network may be a moving access network. 
     In an example, the network may comprise a non-terrestrial network (NTN) type backhaul interface. The NTN type backhaul interface comprises at least one of a low earth orbit (LEO) satellite type, a medium earth orbit (MEO) satellite type, a geostationary earth orbit (GEO) satellite type, an unmanned aircraft system (UAS) platform type, a high elliptical orbit (HEO) platform type, and/or the like. 
     In an example, the first registration request message may further comprise a registration area update type. The registration area update type may indicate a geographical zone-based tracking type for a registration area update from a geographical zone-based tracking and a cell-based tracking. 
     In an example, the cell-based tracking may be based on an area identity of a cell which is broadcasted by an access network. 
     In an example, a wireless device may receive from an access network, access network information. The wireless device may select a registration area update type as a geographical zone-based based on the access network information. The wireless device may send to an access and mobility management function (AMF), a first registration request message. The first registration request message may comprise the registration area update type, a geographical location of the wireless device, and/or the like. 
     In an example the wireless device may receive from the AMF, a registration accept message comprising registration area update information. The wireless device may determine a change of a location of the wireless device based on the registration area update information. 
     The wireless device may send, to the AMF, a second registration request message indicating the change of the location of the wireless device. 
     The first registration request message may further comprise a tracking area identity of a serving cell. 
     The selecting may be further based on a wireless device capability of a geographical location awareness. 
     In an example, the access network information may indicate a low earth orbit (LEO) satellite type. 
     In an example the access network information may indicate a network capability of the geographical zone-based area tracking. 
     In an example, the geographical location of the wireless device may comprise at least one of a latitude and longitude of the wireless device, altitude of the wireless device, time stamp of the geographical location, and/or the like. 
     In an example, an access and mobility function (AMF) may receive from a wireless device, a registration request message. The registration request message may comprise a registration area update type, a geographical location of the wireless device, and/or the like. 
     In an example, the AMF may determine a registration area update type and geographical zone information of the wireless device. The AMF may send a registration accept message to the wireless device, indicating a successful registration of the wireless device. The registration accept message may comprise the geographical zone information, the registration area update type, and/or the like. 
     The AMF may receive a registration request message indicating a change of the wireless device location. 
     Existing technologies may not be efficient if a wireless device moves within a border area between different geographical zones. In an example, the wireless device may be located at a border area between a first zone identity and a second zone identity. The wireless device may move from an area of the first zone identity across the border area and may send a registration request message relating to the second zone identity. In the case where the wireless device moves near the border between two zones, it is likely to cross the border frequently. A ‘ping-pong’ problem arises, meaning that the wireless device is frequently re-registering in one zone and then the other in a back-and-forth fashion. This may increase signaling due to an excessive number of registration request messages, and/or the like. As a result, the signaling load and power consumption within the network and the device may be increased. For the wireless device, an improved geographical zone-based registration area tracking mechanism is needed to decrease the ping-pong issue and reduce power consumption of the wireless device. 
     In an example embodiment, a network and a wireless device may support a flexible zone-based registration tracking. The flexible zone-based registration tracking may comprise two actions, (1) a wireless device may provide current geographical coordinates of the wireless device to an AMF and (2) the AMF may allocate to the wireless device a flexible zone based on the current geographical coordinates of the wireless device. In an example, the wireless device may send a first registration request message to an AMF. The first registration request message may comprise a first geographical coordinate of a first geographical location. The AMF may determine a first flexible geographical zone of the wireless device based on the first geographical coordinates, speed and/or direction information of the wireless device (for example, average speed or direction over a period of time prior to sending of the registration request message), a subscribed service area of the wireless device, and/or the like. For example, a center of the first flexible geographical zone may include the first geographical coordinate of the wireless device. For example, the AMF may set the first geographical zone to a circular shape with a radius, having the first geographical coordinate as the center. For example, the AMF may set the first geographical zone to an elliptical shape with the first geographical coordinate as a center of the ellipse or a first focus of the ellipse. The position of the second focus of the ellipse (relative to the first focus) may correspond to the direction of the wireless device, and the distance between the foci may correspond to the speed of the wireless device. The first flexible geographical zone may be a registration area of the wireless device and the AMF may employ the first flexible geographical zone as a paging area of the wireless device. The wireless device may send a second registration request message in response to leaving the first flexible geographical zone. Implementation of an example embodiment may increase radio resource utilization efficiency by reducing unnecessary registration requests and power consumption of the wireless device. 
       FIG.  34    illustrates an example embodiment of present disclosure.  FIG.  34    depicts two fixed geographical zones (e.g. zone 1, zone 2) and one flexible geographical zone. As depicted in  FIG.  34   , a wireless device may support a flexible zone-based registration area tracking. The wireless device may send a first registration request message to an AMF. The first registration request message may comprise first geographical coordinates of a first location of the wireless device. The wireless device may receive a flexible geographical zone information comprising a radius (depicted as R) of a zone in response to sending the first registration request message. The flexible geographical zone (e.g. flexible zone in  FIG.  34   ) may be an area (e.g., a circle) with a center being the first location (e.g. the first coordinates) and a radius as depicted by R. In an example, the wireless device may not send a second registration request message if the wireless moves inside the flexible geographical zone. In an example, the wireless device may not send a second registration request message if a distance between the wireless device and the first coordinates being smaller than the radius R. In an example, the wireless device may not send a second registration request message unless a distance between the wireless device and the first geographical coordinates exceeds the radius R. In an example, the wireless device may send a second registration request message if the wireless device moves out of the flexible geographical zone. In an example, the wireless device may send a second registration request message if a distance between the wireless device and the first coordinates being larger than the radius ‘R. The wireless device may cross a border area between the fixed zone 1 and the fixed zone 2 when the wireless device is moving within the flexible geographical zone. If the wireless device uses the flexible zone-based registration tracking, the wireless device may not be required to send a second registration request message to update a registration area of the wireless in response to crossing the fixed zone. 
       FIG.  35    illustrates an example embodiment of the present disclosure. The wireless device may be located in a first geographical location. The wireless device and a network may support a flexible zone-based registration area tracking. The wireless device may send a first registration request message to an AMF, wherein the first registration request message may comprise first coordinates of the first geographical location. The AMF may determine a first flexible zone of the wireless device (e.g., flexible zone 1) comprising a radius ‘R’ of a zone. The AMF may send a first registration accept message to the wireless device, in response to the determining. The first registration accept message may comprise first flexible geographical zone information. The first flexible geographical zone information may comprise the radius ‘R’, a geographical coordinates, and/or the like. The wireless device may determine a first flexible zone of the wireless device based on the first flexible geographical zone information. In an example, the first flexible zone may be a circle with a center being the geographical coordinates and a radius being the ‘R’. The first flexible zone may be a registration area of the wireless device. In an example embodiment, the geographical coordinates may be the first geographical location (e.g. first coordinates). If the geographical coordinates are absent in the first flexible geographical zone information, the geographical coordinates may be the first coordinates (e.g., the first geographical location, the first geographical location). Sometime later, the wireless device may move to a second geographical location. In an example, the wireless device may determine that the second geographical location is out of the first flexible zone (e.g., flexible zone 1). In an example, the wireless device may determine that a distance between the first geographical location (e.g., first coordinates) and the second geographical location (e.g., second coordinates of the second geographical location) may be larger than the radius ‘R’. The wireless device may send a second registration request message to the AMF, in response to the determination. The second registration request message may comprise the second geographical location (e.g., second coordinates). The AMF may determine a second flexible zone of the wireless device (e.g., flexible zone 2) comprising a radius ‘R’ of a zone. The radius ‘R’ of the first flexible zone and the radius ‘R’ of the second flexible zone may be different. The wireless device may receive a second registration accept message comprising a second flexible geographical zone information (e.g., radius ‘R’). The wireless device may determine a second flexible zone (e.g. flexible zone 2). The second flexible zone may be a registration area of the wireless device. 
       FIG.  36    illustrates an example embodiment of present disclosure. As depicted in example  FIG.  36   , a radius of the first flexible zone (e.g., flexible zone 1) and a radius of the second flexible zone (e.g., flexible zone 2) may be different. In an example, the radius of the second flexible zone is larger/greater than the radius of the first flexible zone. An AMF may determine larger radius value to configure relatively wide registration area if an average speed of the wireless device is relatively high (e.g. over 300 km/h). Configuring/allocating relatively wide registration area by a network node may decrease a number of registration area update procedure. In an example implementation, a shape of a flexible zone may be arbitrarily shaped, rectangular, elliptical, square, triangular, and/or the like. 
       FIG.  37    illustrates an example embodiment of present disclosure on procedure for a flexible zone-based registration area update. In an example, a wireless device may be turned on or may enter a coverage area of a network. The network may comprise a non-terrestrial network (NTN) type access network. In an example, the NTN type access network may comprise a low earth orbit (LEO) satellite type, a medium earth orbit (MEO) satellite type, a geostationary earth orbit (GEO) satellite type, an unmanned aircraft system (UAS) platform type, a high elliptical orbit (HEO) platform type, and/or the like. In an example, the access network may be a moving access network. 
     The wireless device may determine a registration area update type to perform registration with a network (e.g., a core network (e.g., AMF)) via the access network, RAN, and/or the like. The registration area update type may comprise a cell-based tracking type, a geographical zone-based tracking type, a flexible zone-based tracking type, and/or the like. The cell-based tracking type may be a registration area update type based on tracking areas which is broadcasted by an access network as explained in  FIG.  21   . The cell-based tracking type may be a registration area update type based on a relative location with respect to a location of an access network, access network node, cell, and/or the like. The geographical zone-based tracking type may be a registration area update type based on a geographical zone identity with respect to an objective coordinate system. The geographical zone-based tracking type may be tracking, and update of the geographical zone identity based on a mobility of the wireless device. The geographical zone may be a fixed geographical zone. In an example, the objective coordinate system may be a planet (e.g., the earth). The wireless device may determine the geographical zone identity based on an absolute geographical coordinate of the wireless device and a geographical zone configuration parameter. The flexible zone-based tracking type may be a registration area update type based on a flexible geographical zone with respect to an objective coordinate system. In an example, the objective coordinate system may be a planet (e.g., the earth). In an example, the network (e.g., AMF, PCF) may allocates/provide the flexible geographical zone based on a location of the wireless device (e.g. a geographical coordinates of the wireless device). The flexible geographical zone may be based on an absolute geographical location of the objective coordinate system (e.g., the earth). In an example, the AMF may determine the flexible geographical zone of the wireless device based on the location of the wireless device (e.g. geographical coordinates of the wireless device), a speed (e.g., average speed) of the wireless device, direction of the wireless device mobility (e.g., moving direction), a UE usage type, local policy, history of the wireless device trajectory, a subscription information (e.g. allowed service area of the wireless device), and/or the like. The flexible geographical zone may be flexible in terms of a location of the zone and a size and shape of the zone. The center (e.g., focus) of the flexible geographical zone may be a last reported location of the wireless device. The center of the flexible geographical zone may be vary based on the last reported location information of the wireless device. A shape and a size of the flexible geographical zone may vary in response to a characteristic of the wireless device. The network (e.g., AMF) may determine a center location, a shape and a size of the flexible geographical zone based on the characteristic of the wireless device (e.g., UE usage type, an average speed, a direction of the wireless device mobility). In an example, the shape of the geographical zone may be a circle, rectangle, rectangular, square, polyhedron, elliptical and/or the like. 
     In an example, the wireless device may select the flexible zone-based registration update type. In an example implementation, the network (e.g., AMF) may request to select the flexible zone-based registration update type to the wireless device if the cell-based tracking type and the geographical zone-based tracking type may be inefficient. In an example, if the access network is a moving access network type, the cell-based tracking type may not be appropriate. In an example, if the wireless device frequently moves between two or more different fixed geographical zones/regions, the geographical zone-based tracking type may not be appropriate. 
     In an example, the wireless device may be in a first geographical location. If the wireless device determines to use the flexible zone-based tracking type, the wireless device may determine a first geographical coordinates of the first geographical location. In an example, the wireless device may code the first geographical coordinates as explained in  FIGS.  23 A and  23 B  or in  FIGS.  24 A and  24 B . The wireless device may send a first registration request message to an AMF, in response to the determination. The first registration request message may comprise a registration type, a UE identity (e.g., SUCI, 5G-GUTI), the location of the UE (e.g., last visited TAI), requested NSSAI, UE mobility management context information, information for the MICO mode usage, a registration area update type, the first geographical coordinates and/or the like. In an example, the registration type may indicate a mobility registration. In an example, the registration area update type may be a flexible zone-based tracking type. In an example, the first registration request message may further comprise a speed of the wireless device (e.g. an average speed), a direction of the mobility of the wireless device, a mobility pattern of the wireless device, an indication indicating a privacy request of the wireless device, a time stamp of the first geographical coordinate, and/or the like. In an example, the network (e.g., AMF) may use the average speed of the wireless device to determine a size or a shape of a first flexible zone of the wireless device. The network (e.g., AMF) may use the direction of the mobility to determine a shape of a flexible zone. If a characteristic of the wireless device mobility is directional, the AMF may allocate an ellipse shape for a flexible zone of the wireless device. In an example, the rectangular may be directional based on the mobility of the wireless device. The flexible zone information may comprise a width of a zone, a length of a zone, an angle (direction) of a zone, a center of a zone, and/or the like. The speed/direction of the wireless device mobility may be provided by the wireless device. In an example, the speed/direction of the wireless device may be provided by a network function (e.g. application function, NWDAF (Network Data Analytics Function), UDM, NEF). 
     In an example, the mobility pattern may comprise an indication indicating stationary, an indication indicating local, an indication indicating global. The network (e.g., AMF) may use the mobility pattern of the wireless device to determine a size or a shape of a first flexible zone of the wireless device. The network may allocate/determine a relative smaller size (e.g., 50 meters) of first flexible zone in response to the indication indicating stationary. The network may allocate/determine the first flexible zone not crossing a country border in response to the indication indicating a local. The network may allocate/determine the first flexible zone across multiple countries in response to the indication indicating a global. 
     In an example, the network (e.g., AMF) may use the indication indicating a privacy request to determine whether an exposure of the first geographical coordinate to 3&#39;rd party is allowed or not. 
     In an example, the network may use the time stamp to determine a center of the first flexible zone. In an example, if the time stamp indicates the first coordinates is not recent information (e.g. 1 hour ago), the network (e.g., AMF) may not use the first coordinates for the center of the first flexible zone. 
     The AMF may send a subscription information query message to a UDM in response to receiving the first registration request message. The UDM may send a subscription information query response message to the AMF in response to receiving the subscription information query message. The subscription information query response message may comprise subscribed regions of the wireless device, mobility pattern provided by a 3&#39;rd party and/or the like. 
     The AMF may send a first registration accept message to the wireless device in response to receiving the first registration request message. In an example, the first registration accept message may comprise 5G-GUTI, a registration area, a periodic registration area update time value, a MICO mode indication, confirmed registration update type, a first flexible zone information, and/or the like. If the AMF determine to use the flexible zone-based tracking type for registration update, the AMF may comprise the first flexible zone information for the first flexible zone. In an example implementation, the registration area may comprise the first flexible zone information. 
     In response to receiving the first registration accept message, the wireless device may determine a flexible zone (e.g., the first flexible zone) based on the first flexible zone information. In an example, a shape of the flexible zone may be a rectangular and the first flexible zone information may comprise a length of a zone and a width of a zone. The first flexible zone with a rectangular shape may be centered by the first geographical coordinates with the length and the width. In an example implementation, the shape of the flexible zone may be a circle and the first flexible zone information may comprise a radius ‘R’ of a zone. The first flexible zone may be a circle centered by the first geographical coordinates with the radius ‘R’. In an example, the first flexible zone information may further comprise a third geographical coordinates. The center of the rectangular may be the third geographical coordinates if the first flexible zone information comprises the third geographical coordinates. The center of the circle may be the third geographical coordinates if the first flexible zone information comprises the third geographical coordinates. In an example implementation, the shape of the flexible zone may be an ellipse and the first flexible zone information may comprise a center (e.g., focus), a semi-major axis, a semi-minor axis, an angle and/or the like. In an example implementation, the shape of the flexible zone may be an ellipse and the first flexible zone information may comprise two centers (e.g. two geographical coordinates, foci F1, F2), a distance, a semi-major axis, and/or the like. In an example implementation, the flexible zone information (e.g., the first flexible zone information) may further comprise shape information of the zone and the shape information may comprise a rectangular, a circle, an ellipse and/or the like. 
     The wireless device may monitor/measure whether the wireless device moves out of the registration area (e.g., the first flexible zone, the flexible zone). In an example, the wireless device may determine whether the wireless device has left the first flexible zone based on a second geographical location. If the first flexible zone is a circle, the wireless device may determine the wireless has left the first flexible zone in response to a distance between the first geographical coordinates (or third geographical coordinates) and a second geographical coordinates of the second geographical location being larger than a radius ‘R’. In an example, the second geographical coordinates of the wireless device may be a current geographical coordinates (e.g., current geographical location of the wireless device). 
     The wireless device may send a second registration request message to the AMF, in response to the wireless device determines that the wireless device has left the registration area (e.g., the first flexible zone) of the wireless device. The second registration request message may comprise the second geographical coordinates of the wireless device. The AMF may determine a second flexible zone based on the second geographical coordinates, speed and/or direction information of the wireless device (for example, average speed or direction over a period of time prior to sending of the registration request message), a subscribed service area of the wireless device, and/or the like. In an example, the second geographical coordinates may be a center of the second flexible zone. The AMF may send a second registration accept message comprising second flexible zone information to the wireless device in response to the determining. In an example, the second flexible zone may be same shape with the first flexible zone. In an example, the second flexible zone may be different shape with the first flexible zone. The AMF may comprise the second flexible zone information based on the determination of the second flexible zone. In an example, a shape of the second flexible zone may be a rectangular and the second flexible zone information may comprise a length of a zone and a width of a zone. The second flexible zone with a rectangular shape may be centered by the second geographical coordinates with the length and the width. In an example implementation, the shape of the second flexible zone may be a circle and the second flexible zone information may comprise a radius ‘R’ of a zone. The second flexible zone may be a circle centered by the second geographical coordinates with the radius ‘R’. In an example, the second flexible zone information may further comprise a third geographical coordinates. The center of the rectangular may be the third geographical coordinates if the second flexible zone information comprises the third geographical coordinates. The center of the circle may be the third geographical coordinates if the second flexible zone information comprises the third geographical coordinates. In an example implementation, the shape of the flexible zone may be an ellipse and the second flexible zone information may comprise a center (e.g., focus), a semi-major axis, a semi-minor axis, an angle and/or the like. In an example implementation, the shape of the second flexible zone may be an ellipse and the second flexible zone information may comprise two centers (e.g. two geographical coordinates, foci F1, F2), a distance, a semi-major axis, and/or the like. In an example implementation, the flexible zone information (e.g., the second flexible zone information) may further comprise shape information of the zone and the shape information may comprise a rectangular, a circle, an ellipse and/or the like. 
       FIG.  38    shows an example flow chart of a present disclosure, how a wireless device determines whether the wireless device has left a flexible zone. If a distance between a center of the flexible zone and current geographical coordinates is larger/greater than a radius ‘R’, the wireless device may determine that the wireless device has left the flexible zone. The wireless device may send a registration request message to an AMF to update a registration area of the wireless device in response to the determination. 
       FIG.  39    shows an example flow chart of a present disclosure, how an AMF performs a paging procedure. The AMF may determine to page a wireless device in response to receiving a connection request message for a wireless device. If the wireless device is in a CM-IDLE/RRC-IDLE state, the AMF may trigger a paging procedure for the wireless device. the AMF may select one or more access network(s) which support/serve a registration area (e.g., a flexible zone) of the wireless device in current time. The AMF may select one or more access network(s) based on an area of the flexible zone and an event time value. In an example, if the wireless device receives the connection request message at 10 PM, the AMF may select one or more access network(s) which serve the flexible zone at 10 PM. The AMF may send a N2 paging message comprising the flexible zone information to the one or more access network(s). In an example, the AMF may take into account processing time to select the one or more access network(s). In an example, the AMF receives the connection request message at 10 PM and the processing time is 1 second then the AMF may select one or more access network(s) serving the registration area at 10 PM and 1 second. 
     In an example, a wireless device may send to an access and mobility management function (AMF) via an access network, a first registration request message comprising a first geographical coordinate of a first geographical location. The wireless device may receive a first registration accept message comprising first flexible zone information of the wireless device from the AMF. The wireless device may determine that the wireless device has left a first zone of the first flexible zone information based on a second geographical coordinate of a second geographical location. The wireless device may send a second registration request message comprising the second geographical coordinate, in response to the determining. 
     In an example, a center of the first zone may be the first geographical coordinate. The wireless device may receive from a network, an indication indicating a flexible geographical zone-based registration area update type. The network may be an access network. The network may be an AMF. 
     The first flexible zone information may comprise a length of a zone and a width of a zone. The first zone may be a rectangular centered by the first geographical coordinate. 
     The first flexible zone information may comprise a radius of a zone. The first zone may be a circle centered by the first geographical coordinate. 
     In an example, the wireless may determine that the wireless has left the first zone if a distance from the first geographical coordinate and the second geographical coordinate is larger than the radius. The wireless device may receive a second registration accept message in response to the sending the second registration request message. The second registration request may comprise a second geographical zone information. 
     In an example, a center of a second zone based on the second geographical zone information may be the second geographical coordinate. The gross area of the first zone and a gross area of the second zone may be different. 
     In an example, the first flexible zone information may further comprise a third geographical coordinate. A center of the first zone may be the third geographical coordinate. 
     In an example, the access network may be a moving access network. The access network comprises at least one of, a low earth orbit (LEO) satellite type, a medium earth orbit (MEO) satellite type, a geostationary earth orbit (GEO) satellite type, an unmanned aircraft system (UAS) platform type, a high elliptical orbit (HEO) platform type. 
     In an example, the first registration request message may further comprise at least one of an average speed of the wireless device, a mobility pattern of the wireless device, an indication indicating a privacy request of the wireless device, a time stamp of the first geographical coordinate, and/or the like. 
     The mobility pattern may comprise at least one of an indication indicating stationary, an indication indicating local, an indication indicating global, and/or the like. 
     In an example, the network may not exposure a first coordinate to 3&#39;rd party in response to the indication indicating a privacy request. 
     In an example, the first flexible zone information may be a first flexible geographical zone information. 
     In an example, a wireless device may send to an AMF via an access network, a first registration request message comprising a first geographical coordinate of a first geographical location. The wireless device may receive from the AMF, a registration accept message comprising a radius value. The wireless device may determine that a distance between the first geographical coordinate and a second geographical coordinate of a second geographical location is larger than the radius value. The wireless device may send a second registration request message comprising the second geographical coordinate, in response to the determining. 
     An AMF may receive from a wireless device, a first registration request message comprising a first geographical coordinate of the wireless device. The AMF may determine a first flexible zone information of the wireless device based on the first geographical coordinate, in response to a flexible geographical zone-based registration area update type being authorized. The AMF may send a first registration accept message comprising the first flexible zone information. The determining is based on at least one of a speed of the wireless device, a subscribed service area of the wireless device, history moving information of the wireless device. 
     According to various embodiments, a device such as, for example, a wireless device, off-network wireless device, a base station, and/or the like, may comprise one or more processors and memory. The memory may store instructions that, when executed by the one or more processors, cause the device to perform a series of actions. Embodiments of example actions are illustrated in the accompanying figures and specification. Features from various embodiments may be combined to create yet further embodiments. 
       FIG.  40    is a flow diagram as per an aspect of an example embodiment of the present disclosure. At  4010 , a wireless device may send to an access and mobility management function (AMF) via an access network, a first registration request message comprising a first geographical coordinate of a first geographical location. At  4020 , the wireless device may receive, from the AMF, a registration access message comprising a radius value. At  4030 , the wireless device may move to a second geographical location. At  4040 , the wireless device may determine that a distance between the first geographical coordinate and a second geographical coordinate of the second geographical location is larger than the radius value. At  4050 , in response to the determination, the wireless device may send to the AMF, a second registration request message comprising the second geographical coordinate. 
     According to an embodiment, the first zone may be a circle centered by the first geographical coordinate with the radius value. The determining may be further based on that the wireless device left the first zone. 
     According to an embodiment, the first registration request message may comprise an average speed of the wireless device. The first registration request message may comprise a mobility pattern of the wireless device. The first registration request message may comprise a direction of a movement of the wireless device. The first registration request message may comprise an indication indicating a privacy request of the wireless device. The first registration request message may comprise a time stamp of the first geographical coordinate. According to an embodiment, the mobility pattern may comprise an indication indicating stationary. The mobility pattern may comprise an indication indicating local. The mobility pattern may comprise an indication indicating global. 
     According to an embodiment, the AMF may not expose geographical coordinates of the wireless device to third parties in response to the indication indicating the privacy request. 
     According to an embodiment, the wireless device may receive a second registration accept message in response to sending the second registration request message. The second registration accept message may comprise second geographical zone information. According to an embodiment, the second geographical zone information may comprise a length of a zone. The second geographical zone information may comprise a width of the zone. According to an embodiment, a second zone may be a rectangular shape centered by the second geographical coordinate with the length and the width. 
     According to an embodiment, the access network may be a moving network. According to an embodiment, the access network may comprise a low earth orbit (LEO) satellite. The access network may comprise a low earth orbit (LEO) satellite a medium earth orbit (MEO) satellite. The access network may comprise a geostationary earth orbit (GEO) satellite. The access network may comprise an unmanned aircraft system (UAS) platform. The access network may comprise a high elliptical orbit (HEO) platform. 
       FIG.  41    is a flow diagram as per an aspect of an example embodiment of the present disclosure. At  4110 , an access and mobility management function (AMF) may receive from a wireless device, a first registration request message comprising a first geographical coordinate of the wireless device. At  4120 , the AMF may determine a first flexible zone information of the wireless device based on the first geographical coordinate. The determination may be in response to a flexible geographical zone-based registration area update type being authorized. At  4130 , the AMF may send a first registration accept message comprising the first flexible zone information. According to an embodiment, the determination may be based on a speed of the wireless device. The determination may be based on subscribed service area of the wireless device. The determination may be based on a history movement information of the wireless device. 
     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. 
     Many of the elements described in the disclosed embodiments may be implemented as modules. A module is defined here as an isolatable element that performs a defined function and has a defined interface to other elements. The modules described in this disclosure may be implemented in hardware, software in combination with hardware, firmware, wetware (e.g. hardware with a biological element) or a combination thereof, which may be behaviorally equivalent. For example, modules may be implemented as a software routine written in a computer language configured to be executed by a hardware machine (such as C, C++, Fortran, Java, Basic, Matlab or the like) or a modeling/simulation program such as Simulink, Stateflow, GNU Octave, or LabVIEWMathScript. Additionally, it may be possible to implement modules using physical hardware that incorporates discrete or programmable analog, digital and/or quantum hardware. Examples of programmable hardware comprise: computers, microcontrollers, microprocessors, application-specific integrated circuits (ASICs); field programmable gate arrays (FPGAs); and complex programmable logic devices (CPLDs). Computers, microcontrollers and microprocessors are programmed using languages such as assembly, C, C++ or the like. FPGAs, ASICs and CPLDs are often programmed using hardware description languages (HDL) such as VHSIC hardware description language (VHDL) or Verilog that configure connections between internal hardware modules with lesser functionality on a programmable device. Finally, it needs to be emphasized that the above mentioned technologies are often employed in combination to achieve the result of a functional module. 
     Example embodiments of the invention may be implemented using various physical and/or virtual network elements, software defined networking, virtual network functions. 
     The disclosure of this patent document incorporates material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, for the limited purposes required by law, but otherwise reserves all copyright rights whatsoever. 
     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. 
     Further, the purpose of the Abstract of the Disclosure is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The Abstract of the Disclosure is not intended to be limiting as to the scope in any way. 
     Finally, it is the applicant&#39;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.