SYSTEM AND METHOD FOR ALLOWED NETWORK SLICE SELECTION ASSISTANCE INFORMATION HANDLING

A system comprises one or more devices that implement a network function. The network function receives a connection request for a User Equipment (UE) device, the connection request including requested Network Slice Selection Assistance Information (NSSAI) for a mobile network. The network function retrieves subscribed NSSAI that includes NSSAI of slices from a subscription associated with the UE device. The network function determines expanded allowed NSSAI based on the subscribed NSSAI and NSSAI supported by the network. The network function sends, to the user device, the expanded allowed NSSAI.

BACKGROUND INFORMATION

Next Generation mobile networks, such as Fifth Generation (5G) mobile networks, are designed to increase data transfer rates, increase spectral efficiency, improve coverage, improve capacity, and reduce latency. For example, a 5G network may incorporate “network slicing” technology to increase network efficiency and performance.

Network slicing is a type of virtualized networking architecture that involves partitioning of a single physical network into multiple virtual networks. The partitions, or “slices,” of the virtualized network may be customized to meet the specific needs of applications, services, devices, customers, or operators. Each network slice can have its own architecture, provisioning management, and security that supports a particular application or service.

DETAILED DESCRIPTION

User equipment devices (UEs) may execute various applications that generate network traffic with different service requirements. These different service requirements may be met through network slicing. A network slice refers to a complete logical network that includes components, of a Radio Access Network (RAN) and core network, which provide certain telecommunication services and network capabilities that can vary from slice to slice. Bandwidth, capacity, and connectivity functions are allocated within each network slice to meet the requirements of the network slices. Selection of network slices for a particular application can thus have significant impact on network performance and user experience.

Many advanced networks today use Network Slice Selection Assistance Information (NSSAI) and Single NSSAI (S-NSSAI) to identify network slices. The NSSAI may provide information that permits selections of a particular network slice, and a corresponding set of network functions (e.g., access and mobility management functions (AMFs)) that may be associated with that particular network slice. Different NSSAIs can be given by the network or requested by UEs. As used herein, the term NSSAI may be used to refer to network slice information or the actual network slice.

Typically, as part of a registration process, an application running on a UE may request an NSSAI that has been previously provisioned for use by the UE, if available. Assuming the requested NSSAI is supported by network and is part of a user's subscription, the network may allow use of the NSSAI by the UE. If the requested NSSAI is not supported by the network or is not part of the user's subscription, the network may provide alternative NSSAI for the UE registration. However, if one or more of the alternative NSSAI that the network provides has not been previously provisioned for use by the UE, the alternative NSSAI will not be used in the current connection request. That is, when a slice is subsequently added to a UE subscription or otherwise becomes available to the UE, the UE may not know that the new slice can be requested until a power cycle or mobility registration is performed.

Systems and methods described herein enable immediate use of updated network slice options by UE devices.FIG.1illustrates concepts described herein. A system10may include a mobile network100(e.g., including a core network and RAN) that supports network slicing for a UE110.

Mobile network100(also referred to herein as “network100”) may include a Public Land Mobile Network (PLMN) and possibly one or more other networks (not shown inFIG.1) that provides wireless (e.g., Radio Frequency (RF)) communication with UEs110. Mobile network100may be composed of sub-networks, such as a RAN and a core network, as described further herein.

In accordance with 5G network standards, mobile network100can provide “Allowed NSSAI,” “Configured NSSAI,” and “Rejected NSSAI,” while the UE110can use “Requested NSSAI” to request a network slice. Under the current standards, the Allowed NSSAI can be defined as the intersection of the Requested NSSAI, the Network Supported NSSAI, and the customer's subscribed NSSAI. The Rejected NSSAI can be defined as NSAAI that is included in Requested NSSAI but not supported by the network or not in the subscribed NSSAI. Configured NSSAI may be defined as the subscribed NSSAI.

InFIG.1, assume mobile network100supports a Slice1and a Slice2, and UE110has a subscription for Slice1. A customer (e.g., a user of UE110) may submit an order to add Slice2to the customer subscription. As indicated at reference112, network100may update the customer subscription to add the corresponding NSSAI for Slice2, which can eventually be communicated to UE110.

At the time of subscription update112, UE110may be in a connected or idle mode on a 5G Standalone (SA) network, may be on connected or idle mode of Non-Standalone (NSA) network/LTE network, or can be powered off. If UE110is in SA connected mode114when mobile network100pushes the network slice subscription to UE110, UE110would not be aware of the newly provisioned NSSAI for Slice2. Instead, UE110will use NSSAI for Slice1in request116. Under conventional network configurations, mobile network100would respond to request116by providing Allowed NSSAI for the requested slice (Slice1, assuming Slice1is supported by network100), even though the customer had recently subscribed to Slice2.

According to implementations described herein, logic in mobile network100is enhanced to respond to request116by providing new Expanded Allowed NSSAI120, which includes NSSAI for both Slice1(e.g., the requested slice) and Slice2(e.g., the newly subscribed slice). Thus, UE110is assured of receiving the NSSAI for a new slice subscription without having to perform a power cycle or make a mobility registration to obtain updated network slice options.

FIG.1illustrates a use case (e.g., subscription updates) wherein systems and methods described herein can enable immediate use of new network slice options by UE devices. In other implementations, systems and methods described herein can be applied to provide immediate access to NSSAI for configuration update commands for either RAN or AMF Slice support changes. Additionally, the systems and methods may be applicable to registration accept messages on an initial or mobility registration case.

FIG.2illustrates an exemplary network environment200in which system10ofFIG.1may be implemented. As shown, network environment200may include a UE110, an access network204, a core network206, and a data network208. Access network204and a core network206may be part of mobile network100.

UE110may include a wireless computational communication device. Examples of UE110include: a smart phone; a tablet device; a wearable computer device (e.g., a smart watch); a global positioning system (GPS) device; a laptop computer; a media playing device; a portable gaming system; an autonomous vehicle navigation system; a sensor, such as a pressure sensor or; and an Internet-of-Things (IoT) device. In some implementations, UE110may correspond to a wireless Machine-Type-Communication (MTC) device that communicates with other devices over a machine-to-machine (M2M) interface, such as LTE-M or Category M1 (CAT-M1) devices and Narrow Band (NB)-IoT devices.

Access network204may allow UE110to access core network206. To do so, access network204may establish and maintain, with participation from UE110, an over-the-air channel with UE110; and maintain backhaul channels with core network206. Access network204may relay information through these channels, from UE110to core network206and vice versa. Access network204may include a Long-term Evolution (LTE) radio network and/or a Fifth Generation (5G) radio network or other advanced radio network. These networks may include many central units (CUs), distributed units (DUs), radio units (RUS), and wireless stations, one of which is illustrated inFIG.2as wireless station210for establishing and maintaining over-the-air channel with UE110. Wireless station210may include a 4G, 5G, or another type of base station (e.g., eNB, gNB, etc.) that comprise one or more radio frequency (RF) transceivers. In some implementations, wireless station210may be part of an evolved Universal Mobile Telecommunications Service (UMTS) Terrestrial Network (eUTRAN).

Core network206may manage communication sessions of subscribers connecting to core network206via access network204. For example, core network206may establish an Internet Protocol (IP) connection between UEs110and data network208. In some implementations, core network206may include a 5G core network. In other implementations, core network206may include a 4G core network (e.g., an evolved packet core (EPC) network) in combination with a 5G network or another type of core network.

The components of core network206may be implemented as dedicated hardware components or as virtualized functions implemented on top of a common shared physical infrastructure using Software Defined Networking (SDN). For example, an SDN controller may implement one or more of the components of core network206using an adapter implementing a Virtual Network Function (VNF) virtual machine, a container, an event driven server-less architecture interface, and/or another type of SDN component. The common shared physical infrastructure may be implemented using one or more devices700described below with reference toFIG.7in a cloud computing center associated with core network206. Exemplary components of core network206are described below with reference toFIG.3.

Data network208may include one or more networks connected to core network206. In some implementations, a particular data network208may be associated with a data network name (DNN) in 5G, and/or an Access Point Name (APN) in 4G, and a UE110may request a connection to data network208using a DNN or APN. Data network208may include, and/or be connected to and enable communication with, a local area network (LAN), a wide area network (WAN), a metropolitan area network (MAN), an autonomous system (AS) on the Internet, an optical network, a cable television network, a satellite network, another wireless network (e.g., a Code Division Multiple Access (CDMA) network, a general packet radio service (GPRS) network, and/or an LTE network), an ad hoc network, a telephone network (e.g., the Public Switched Telephone Network (PSTN) or a cellular network), an intranet, or a combination of networks. Data network208may include an application server (also simply referred to as application). An application may provide services for a program or an application running on UE110and may establish communication session with UE110via core network206.

As shown, core network206may include one or more network slices212. Depending on the implementation, network slices212, may be implemented within other networks, such as access network204and/or data network208. Access network204, core network206, and data network208may include multiple instances of network slices212. Each network slice212may be instantiated as a result of “network slicing,” which involves a form of virtual network architecture that enables multiple logical networks to be implemented on top of a shared physical network infrastructure using SDN and/or network function virtualization (NFV). Each logical network, referred to as a “network slice,” may encompass an end-to-end virtual network with dedicated storage and/or computational resources that include access network components, clouds, transport, Central Processing Unit (CPU) cycles, memory, etc. Furthermore, each network slice may be configured to meet a different set of requirements and be associated with a particular Quality of Service (QOS) class, a type of service, and/or a particular group of enterprise customers associated with communication devices.

Each network slice212may be associated with an identifier, herein referred to as a Single Network Slice Selection Assistance Information (S-NSSAI). For each UE110that wishes to access a particular network slice, the subscription data for the UE110(stored in core network206, for example) may include the S-NSSAI corresponding to the network slice.

Depending on the implementation, network environment200may include additional networks and components than those illustrated inFIG.2. However, for clarity,FIG.2does not show all components that may be included in network environment200(e.g., routers, bridges, wireless access point, additional UE devices, switches, etc.).

FIG.3depicts exemplary components of a portion300of network environment200according to an implementation. As shown, portion300may include access network204, an application function (AF)312-1, and a portion of core network206. Access network204has been described above with reference toFIG.2. AF312-1is one of what have been referred to as NFs (network functions). AF312-1may provide an application function that belongs to a third party (i.e., an entity different from a service provider) and provides services to UEs110via access network204, core network206, and/or data network208.

InFIG.3, core network206comprises, in addition to other components described with reference toFIG.2, multiple NFs that are implemented in accordance with Service Based Architecture (SBA), either as hardware devices or virtual components (e.g., a container or a virtual machine). Each NF includes a particular set of network functionalities and may act as a consumer NF (an NF that receives services from an NF) or a producer NF (an NF that provides services to consumer NFs).

As shown, core network206includes: an Access and Mobility Management Function (AMF)304, a Session Management Function (SMF)306, a Policy Control Function (PCF)308, a User Plane Function (UPF)310, an AF (Application Function)312-2, a Network Slice Selection Function (NSSF)314, a Unified Data Repository (UDR)316, and a Unified Data Management (UDM)318. Depending on the implementation, core network206may include additional, fewer, or different components than those illustrated inFIG.3.

AMF304may perform registration management, connection management, reachability management, mobility management, lawful intercepts, Short Message Service (SMS) transport between UE110and an SMS function, session management message transport between UE110and SMF306, access authentication and authorization, location services management, support of non-3GPP access networks, and/or other types of management processes. AMF304may page UE110based on mobility category information associated with UE110obtained from UDM318. In some implementations, AMF304may implement some or all of the functionality of managing RAN slices in wireless station210.

SMF306may perform session establishment, modification and/or release; perform IP address allocation and management; perform Dynamic Host Configuration Protocol (DHCP) functions; perform selection and control of UPF310; configure traffic steering at UPF310to guide traffic to the correct destination; terminate interfaces toward PCF308; perform lawful intercepts; charge data collection; support charging interfaces; control and coordinate charging data collection; terminate session management parts of Non-Access Stratum (NAS) messages; perform downlink data notification; manage roaming functionality; and/or perform other types of control plane processes for managing user plane data.

PCF308may support policies to control network behavior, provide policy rules to control plane functions (e.g., to SMF306), access subscription information relevant to policy decisions, perform policy decisions, and/or perform other types of processes associated with policy enforcement.

UPF310may maintain an anchor point for intra/inter-radio access technology (RAT) mobility (e.g., mobility across different radio access technologies; maintain an external Packet Data Unit (PDU) point of interconnect to a data network (e.g., an IP network, etc.); perform packet routing and forwarding; perform the user plane part of policy rule enforcement; perform packet inspection; perform lawful intercept; perform traffic usage reporting; perform Qos handling in the user plane; perform uplink traffic verification; perform transport level packet marking; perform downlink packet buffering; send and forwarding an “end marker” to a RAN node (e.g., wireless station210); and/or perform other types of user plane processes.

AF312-2may provide services associated with a particular application, such as, for example, application on traffic routing, accessing a Network Exposure Function (NEF) (not shown), interacting with a policy framework for policy control, and/or other types of applications. In contrast to AF312-1, AF312-2may reside within core network206and/or access network204.

NSSF314may select a set of network slice instances to serve a particular UE110, determine NSSAI or an S-NSSAI, determine a particular AMF304to serve a particular UE110, and/or perform other types of processes associated with network slice selection or management. In some implementations, NSSF314may receive network slice-related information from a Network Slice Management Function (NSMF) (not shown) that manages network slices. The management may include instantiation, removal, and/or modification of network slices based on specifications. When an NSMF creates a network slice, the NSMF may obtain an S-NSSAI for the network slice and store the S-NSSAI via NSSF314.

UDR316may store subscriber data (e.g., subscriber profile) associated with UEs110, modify subscriber data, and/or delete subscriber data. UDM318may maintain subscription information for UE110; manage subscriptions; generate authentication credentials; handle user identification; perform access authorization based on subscription data; perform network function registration management; maintain service and/or session continuity by maintaining assignment of SMF306for ongoing sessions; support SMS delivery, support lawful intercept functionality; and/or perform other processes associated with managing user data. For example, UDM318may store subscription profiles that include authentication, access, and/or authorization information. Each subscription profile may include information identifying UE110; authentication and/or authorization information for UE110; information identifying services enabled and/or authorized for UE110; device group membership information for UE110; and/or other types of information associated with UE110. Furthermore, the subscription profile may include mobility category information associated with UE110.

Depending on the implementation, core network206may include additional, fewer, and/or different components than those illustrated inFIG.3. Furthermore, depending on the implementation, in addition to the functionalities described above, the components302-320may include additional capabilities. Such capabilities may be implemented through modification of standard interfaces and/or addition of new interfaces for interacting with various network functions.

FIG.4illustrates exemplary processing and messaging in a portion400of network environment200to enable immediate use of new network slice subscriptions by UEs110, according to an implementation. Network portion400may include UE110, access network204, AMF304, NSSF314, and UDM318. In the example ofFIG.4, assume that a subscription for UE110has been updated in UDM318to include NSSAI of a new network slice since the last time UE110was restarted or had a mobility registration.

As shown inFIG.4, UE110may send a connection request410. Connection request410may include an S-NSSAI and/or a network slice instance identifier (ID). Since UE110is unaware of the subscription update at UDM318, the S-NSSAI and/or the network slice instance ID (collectively referred to herein as “Requested NSSAI”) may identify a network slice to which UE110expects to connect (e.g., based on previously-allowed NSSAI prior to the subscription update). Alternatively, connection request may not include Requested NSSAI (e.g., if no preferred slice is known by UE110).

Request410is sent to access network204(or to a wireless station, such as a gNB, in access network204). Access network204forwards a message412to AMF304, conveying UE110's connection request. As such, message412carries the Requested NSSAI of the network slice to which UE110seeks to connect. Upon receipt of message412, AMF304may proceed to access UDM318, for obtaining information in the user subscription profile at UDM318. Accordingly, AMF304sends a request message414to UDM318and obtains a reply416that includes subscribed NSSAI for UE110. The subscribed NSSAI identifies the network slices which UE110is allowed to access or connect, including NSSAI for the newly subscribed slice.

AMF304may receive reply416with the subscribed NSSAI. AMF304may send a message418to NSSF314with the subscribed slice information (from response416) requesting NSSF314to identify other or all network slices that UE110may access. In response to message418, NSSF314may perform calculations420to determine the Expanded Allowed NSSAI, the Configured NSSAI, and/or Rejected NSSAI. While the Configured NSSAI and the Rejected NSSAI may be determined using known approaches, the Expanded Allowed NSSAI may be determined without taking into consideration the Requested NSSAI (from messages410/412). Instead, NSSF314may consider what mobile network100(e.g., access network204and core network206) can support and what UE110is subscribed to. For example, NSSF314may calculate the Expanded Allowed NSSAI as the intersection of the RAN Supported NSSAI, the Core supported NSSAI, and the subscribed NSSAI.

After performing calculations420, and in response to message418, NSSF314may send to AMF304a reply422, which includes the Expanded Allowed NSSAI, the Configured NSSAI, and/or Rejected NSSAI. More specifically, NSSF314may provide in reply422Expanded Allowed NSSAI that includes the Requested NSSAI (assuming the Requested NSSAI contains NSSAI that is valid in the serving PLMN) and any other NSSAI that the UE is subscribed to and supported by mobile network100. Reply422may also include Configured NSSAI (which would include all subscribed NSSAI for the UE110) and Rejected NSSAI (which would include the requested NSSAI if the Requested NSSAI is not supported by mobile network100or not in the subscribed NSSAI).

AMF304may send, in its reply424to message412from access network204, the Expanded Allowed NSSAI, the Configured NSSAI, and/or Rejected NSSAI received from NSSF314in reply422. Access network204may then relay the Expanded Allowed NSSAI, the Configured NSSAI, and/or Rejected NSSAI to UE110in its response426to the connection request. UE110may apply the Expanded Allowed NSSAI immediately to implement a connection using the newly subscribed slice. Thus, by NSSF314/AMF304providing Expanded Allowed NSSAI that includes NSSAI for the newly subscribed slice, additional signaling needed for re-registration to connect to the new slice is avoided.

FIG.5illustrates exemplary processing and messaging in a portion500of network environment200to enable immediate use of new network slice subscriptions by UEs, according to an implementation. In contrast toFIG.4, the processing in messing inFIG.5do not include AMF304directly interacting with an NSSF. As shown, network portion500may include UE110, access network204, AMF304, and UDM318. Some functions of NSSF314described above may be combined in AMF304. Similar to the example ofFIG.4, in the example ofFIG.5, assume that a subscription for UE110has been updated in UDM318to include NSSAI of a new network slice since the last time UE110was restarted or had a mobility registration.

As shown inFIG.5, UE110may send a connection request510. Connection request510may include Requested NSSAI that identifies a network slice to which UE110expects to connect (e.g., based on previously-allowed NSSAI prior to the subscription update). Request510may be sent to access network204, and access network204may forward a message512to AMF304, conveying UE110's connection request. As such, message512carries the Requested NSSAI of the network slice to which UE110seeks to connect. Upon receipt of message512, AMF304may proceed to establish a connection for checking the user subscription profile at UDM318. Accordingly, AMF304may send a request message514to UDM318and may obtain a reply516that includes subscribed NSSAI for UE110. The subscribed NSSAI may identify the network slices which UE110is allowed to access or connect, including NSSAI for the newly subscribed slice.

AMF304may receive reply516with the subscribed NSSAI. In response to message516, AMF304may perform calculations520to determine the Expanded Allowed NSSAI, the Configured NSSAI, and/or Rejected NSSAI. The Expanded Allowed NSSAI may be determined without taking into consideration the Requested NSSAI (from messages510/512). AMF304may consider what network slices mobile network100can support and what UE110is subscribed to, without considering the Requested NSSAI. For example, AMF304may calculate the Expanded Allowed NSSAI as the intersection of the RAN Supported NSSAI, the Core supported NSSAI, and the subscribed NSSAI.

After performing calculations520, and in response to message512, AMF304may send a reply524, which includes the Expanded Allowed NSSAI, the Configured NSSAI, and/or Rejected NSSAI. More specifically, AMF304may provide in reply524Expanded Allowed NSSAI that includes the Requested NSSAI (assuming the Requested NSSAI contains NSSAI that is valid in the serving PLMN) and any other NSSAI that the UE is subscribed to and supported by mobile network100. In some implementations, reply524may also include Configured NSSAI and Rejected NSSAI. AMF304may send reply524to access network204(e.g., a gNB or other wireless station210), which may then relay the Expanded Allowed NSSAI, the Configured NSSAI, and/or Rejected NSSAI to UE110in its response526to connection request510. UE110may apply the Expanded Allowed NSSAI immediately to implement a connection using the newly subscribed slice. Thus, by NSSF314/AMF304providing Expanded Allowed NSSAI that includes NSSAI for the newly subscribed slice, additional signaling of re-registration to connect to the new slice is avoided.

FIG.6is a flow diagram of a process600associated with enabling immediate use of new network slice subscriptions by UE devices, according to an implementation. Process600may be performed by one or more network components, such as those shownFIGS.1-5. As shown, process600may include receiving a configuration update for a UDM subscription change or a mobility network slice support change (605). For example, in one implementation, a user profile in UDM318may be updated to reflect a new subscription. In another implementation, a configuration change to access network204or AMF304may be implemented to support a new network slice.

Process600may further include receiving a connection request (block610) and retrieving subscribed NSSAI (block615). For example, AMF304may receive a connection request from UE110that includes a Requested NSSAI and, in response, retrieve from UDM318subscribed NSSAI for UE110.

Process600may also include determining expanded allowed NSSAI (block620) and sending the expanded allowed NSSAI to the UE (block625). For example, AMF304and/or NSSF314may perform calculations520to determine the Expanded Allowed NSSAI, the Configured NSSAI, and/or Rejected NSSAI. The calculations may be based on (a) what slices UE110is subscribed to (e.g., including any recent subscription additions) and (b) what slices access network204and core network206can support (e.g., including any recent configuration changes). The Expanded Allowed NSSAI may be determined without taking into consideration the Requested NSSAI. AMF304may perform the necessary calculations and/or receive the calculated Expanded Allowed NSSAI, the Configured NSSAI, and/or Rejected NSSAI from NSSF314. AMF304may provide the Expanded Allowed NSSAI, the Configured NSSAI, and/or Rejected NSSAI to UE110in response to the connection request.

FIG.7depicts exemplary components of an exemplary network device700. Network device700may correspond to or be included in any of the devices and/or components illustrated inFIGS.1-6(e.g., UE110, access network204, core network206, data network208, NFs304-318, etc.). In some implementations, network devices700may be part of a hardware network layer on top of which other network layers and NFs may be implemented.

As shown, network device700may include a processor702, memory/storage704, input component706, output component708, network interface708, and communication path712. In different implementations, network device700may include additional, fewer, different, or different arrangement of components than the ones illustrated inFIG.7. For example, network device700may include line cards, switch fabrics, modems, etc.

Processor702may include a processor, a microprocessor, an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), programmable logic device, chipset, application specific instruction-set processor (ASIP), system-on-chip (SoC), central processing unit (CPU) (e.g., one or multiple cores), microcontrollers, and/or other processing logic (e.g., embedded devices) capable of controlling network device700and/or executing programs/instructions.

Memory/storage704may include static memory, such as read only memory (ROM), and/or dynamic memory, such as random access memory (RAM), or onboard cache, for storing data and machine-readable instructions (e.g., programs, scripts, etc.). Memory/storage704may also include an optical disk, magnetic disk, solid state disk, holographic versatile disk (HVD), digital versatile disk (DVD), and/or flash memory, as well as other types of storage device (e.g., Micro-Electromechanical system (MEMS)-based storage medium) for storing data and/or machine-readable instructions (e.g., a program, script, etc.). Memory/storage704may be external to and/or removable from network device700. Memory/storage704may include, for example, a Universal Serial Bus (USB) memory stick, a dongle, a hard disk, off-line storage, a Blu-Ray® disk (BD), etc. Memory/storage704may also include devices that can function both as a RAM-like component or persistent storage, such as Intel® Optane memories.

Depending on the context, the term “memory,” “storage,” “storage device,” “storage unit,” and/or “medium” may be used interchangeably. For example, a “computer-readable storage device” or “computer-readable medium” may refer to both a memory and/or storage device.

Input component706and output component708may provide input and output from/to a user to/from network device700. Input/output components706and708may include a display screen, a keyboard, a mouse, a speaker, a microphone, a camera, a DVD reader, USB lines, and/or other types of components for obtaining, from physical events or phenomena, to and/or from signals that pertain to network device700.

Network interface710may include a transceiver (e.g., a transmitter and a receiver) for network device710to communicate with other devices and/or systems. For example, via network interface710, network device700may communicate over a network, such as the Internet, an intranet, cellular, a terrestrial wireless network (e.g., a WLAN, Wi-Fi, WiMax, etc.), a satellite-based network, optical network, etc. Network interface710may include a modem, an Ethernet interface to a LAN, and/or an interface/connection for connecting network device700to other devices (e.g., a Bluetooth interface).

Communication path or bus712may provide an interface through which components of network device700can communicate with one another.

Network device700may perform the operations described herein in response to processor702executing software instructions stored in a non-transient computer-readable medium, such as memory/storage704. The software instructions may be read into memory/storage704from another computer-readable medium or from another device via network interface710. The software instructions stored in memory/storage704, when executed by processor702, may cause processor702to perform one or more of the processes that are described herein.

According to the description above, a system may comprise one or more device700that implement a network function. The network function receives a connection request for a UE, the connection request including requested NSSAI for a mobile network. The network function retrieves subscribed NSSAI that includes NSSAI of slices from a subscription associated with the UE device. The network function calculates expanded allowed NSSAI based on the subscribed NSSAI and NSSAI supported by the network. The network function sends, to the UE, the expanded allowed NSSAI.

By providing Expanded Allowed NSSAI, the systems and methods described herein enable immediate use of updated network slice options by UE devices without requiring a mobility registration or UE power cycling. In contrast, conventional signaling uses a re-registration message that requires UE devices to have to disconnect and then re-establish all active PDU sessions. Thus, the systems and methods described herein provide a significant reduction in signaling, for both the RAN network and core network, to enable use of updated network slice options by UEs.

The foregoing description of implementations provides illustration, but is not intended to be exhaustive or to limit the invention to the precise form disclosed. Modifications and variations are possible in light of the above teachings or may be acquired from practice of the invention. Also, while a series of blocks have been described with regard toFIG.6the order of the blocks and message/operation flows may be modified in other embodiments. Further, non-dependent blocks may be performed in parallel.