WO2022056431A1 - Efficient access for single operator network slices - Google Patents

Abstract

An apparatus and system to enable single operator network slice access are described. Initial network slice information is contained in new information elements in a SIB. The UE sends an on-Demand SIB request for further SIB information related to Slice/Service type (SST) when in RRC_CONNECTED mode and via a RACH procedure when in RRC_IDLE or INACTIVE mode. The network provides Steering of Roaming (SoR) information in a list for steering the UE to PLMNs dependent on whether the UE is able to simultaneously access multiple PLMNs. Single-Network Slice Selection Assistance Information (S-NSSAI) information, which includes a Slice/Service type (SST) and a Slice Differentiator (SD), also includes an indication that the SD of an S-NSSAI is able to be skipped. The UE may register in different PLMNs using the same radio access technology (RAT) or different RATs.

Description

EFFICIENT ACCESS FOR SINGLE OPERATOR NETWORK SLICES

PRIORITY CLAIM

[0001] This application claims the benefit of priority to United States

Provisional Patent Application Serial No. 63/078,147, filed September 14, 2020, and United States Provisional Patent Application Serial No. 63/080,588, filed September 18, 2020, each of which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

[0002] Embodiments pertain to fifth generation (5G) wireless communications. In particular, some embodiments relate to multi-network slice access and steering of roaming based on supported network slices of multiple networks.

BACKGROUND

[0003] The use and complexity of wireless systems, which include 4^th generation (4G) and 5^th generation (5G) networks among others, has increased due to both an increase in the types of devices user equipment (UEs) using network resources as well as the amount of data and bandwidth being used by various applications, such as video streaming, operating on these UEs. With the vast increase in number and diversity of communication devices, the corresponding network environment, including routers, switches, bridges, gateways, firewalls, and load balancers, has become increasingly complicated, especially with the advent of next generation (NG) (or new radio (NR)) systems. As expected, a number of issues abound with the advent of any new technology.

BRIEF DESCRIPTION OF THE FIGURES

[0004] In the figures, which are not necessarily drawn to scale, like numerals may describe similar components in different views. Like numerals having different letter suffixes may represent different instances of similar components. The figures illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document. [0005] FIG. 1A illustrates an architecture of a network, in accordance with some aspects.

[0006] FIG. 1B illustrates a non-roaming 5G system architecture in accordance with some aspects. [0007] FIG. 1C illustrates a non-roaming 5G system architecture in accordance with some aspects.

[0008] FIG. 2 illustrates a block diagram of a communication device in accordance with some embodiments.

[0009] FIG. 3 illustrates connection of a radio access network (RAN) node to two network slices simultaneously in accordance with some aspects.

[0010] FIG. 4 illustrates System Information (SI) provisioning in accordance with some aspects.

[0011] FIG. 5 illustrates a Random Access procedure in accordance with some aspects. [0012] FIG. 6 illustrates a roaming UE with service on network slices available on different networks in accordance with some aspects.

[0013] FIG. 7 illustrates a procedure to provide a list of preferred public land mobile network (PLMN)/access technology combinations in accordance with some aspects. [0014] FIG. 8 illustrates a procedure to provide a list of preferred PLMN/access technology combinations after registration in accordance with some aspects.

[0015] FIG. 9 illustrates a procedure to provide a list of preferred PLMN/access technology combinations in accordance with some aspects.

DETAILED DESCRIPTION

[0016] The following description and the drawings sufficiently illustrate specific embodiments to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, and other changes. Portions and features of some embodiments may be included in, or substituted for, those of other embodiments. Embodiments set forth in the claims encompass all available equivalents of those claims.

[0017] FIG. 1A illustrates an architecture of a network in accordance with some aspects. The network 140A includes 3GPP LTE/4G and NG network functions that may be extended to 6G functions. Accordingly, although 5G will be referred to, it is to be understood that this is to extend as able to 6G structures, systems, and functions. A network function can be implemented as a discrete network element on a dedicated hardware, as a software instance running on dedicated hardware, and/or as a virtualized function instantiated on an appropriate platform, e.g., dedicated hardware or a cloud infrastructure.

[0018] The network 140A is shown to include user equipment (UE) 101 and UE 102. The UEs 101 and 102 are illustrated as smartphones (e.g., handheld touchscreen mobile computing devices connectable to one or more cellular networks) but may also include any mobile or non-mobile computing device, such as portable (laptop) or desktop computers, wireless handsets, drones, or any other computing device including a wired and/or wireless communications interface. The UEs 101 and 102 can be collectively referred to herein as UE 101, and UE 101 can be used to perform one or more of the techniques disclosed herein.

[0019] Any of the radio links described herein (e.g., as used in the network 140 A or any other illustrated network) may operate according to any exemplaiy radio communication technology and/or standard. Any spectrum management scheme including, for example, dedicated licensed spectrum, unlicensed spectrum, (licensed) shared spectrum (such as Licensed Shared

Access (LSA) in 2.3-2.4 GHz, 3A-3.6 GHz, 3.6-3.8 GHz, and other frequencies and Spectrum Access System (SAS) in 3.55-3.7 GHz and other frequencies). Different Single Carrier or Orthogonal Frequency Domain Multiplexing (OFDM) modes (CP-OFDM, SC-FDMA, SC-OFDM, filter bank-based multicarrier (FBMC), OFDMA, etc.), and in particular 3 GPP NR, may be used by allocating the OFDM carrier data bit vectors to the corresponding symbol resources.

[0020] In some aspects, any of the UEs 101 and 102 can comprise an Intemet-of-Things (IoT) UE or a Cellular IoT (CIoT) UE, which can comprise a network access layer designed for low-power IoT applications utilizing short- lived UE connections. In some aspects, any of the UEs 101 and 102 can include a narrowband (NB) IoT UE (e.g., such as an enhanced NB-IoT (eNB-IoT) UE and Further Enhanced (FeNB-IoT) UE). An IoT UE can utilize technologies such as machine-to-machine (M2M) or machine-type communications (MTC) for exchanging data with an MTC server or device via a public land mobile network (PLMN), Proximity-Based Service (ProSe) or device-to-device (D2D) communication, sensor networks, or IoT networks. The M2M or MTC exchange of data may be a machine-initiated exchange of data. An IoT network includes interconnecting IoT UEs, which may include uniquely identifiable embedded computing devices (within the Internet infrastructure), with short-lived connections. The IoT UEs may execute background applications (e.g., keep- alive messages, status updates, etc.) to facilitate the connections of the IoT network. In some aspects, any of the UEs 101 and 102 can include enhanced MTC (eMTC) UEs or further enhanced MTC (FeMTC) UEs.

[0021] The UEs 101 and 102 may be configured to connect, e.g., communicatively couple, with a radio access network (RAN) 110. The RAN 110 may be, for example, an Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN), aNextGen RAN (NG RAN), or some other type of RAN.

[0022] The UEs 101 and 102 utilize connections 103 and 104, respectively, each of which comprises a physical communications interface or layer (discussed in further detail below); in this example, the connections 103 and 104 are illustrated as an air interface to enable communicative coupling, and can be consistent with cellular communications protocols, such as a Global System for Mobile Communications (GSM) protocol, a code-division multiple access (CDMA) network protocol, a Push-to-Talk (PTT) protocol, a PTT over Cellular (POC) protocol, a Universal Mobile Telecommunications System (UMTS) protocol, a 3 GPP Long Term Evolution (LTE) protocol, a 5G protocol, a 6G protocol, and the like.

[0023] In an aspect, the UEs 101 and 102 may further directly exchange communication data via a ProSe interface 105. The ProSe interface 105 may alternatively be referred to as a sidelink (SL) interface comprising one or more logical channels, including but not limited to a Physical Sidelink Control Channel (PSCCH), a Physical Sidelink Shared Channel (PSSCH), a Physical Sidelink Discovery Channel (PSDCH), a Physical Sidelink Broadcast Channel (PSBCH), and a Physical Sidelink Feedback Channel (PSFCH).

[0024] The UE 102 is shown to be configured to access an access point (AP) 106 via connection 107. The connection 107 can comprise a local wireless connection, such as, for example, a connection consistent with any IEEE 802.11 protocol, according to which the AP 106 can comprise a wireless fidelity (WiFi®) router. In this example, the AP 106 is shown to be connected to the Internet without connecting to the core network of the wireless system (described in further detail below).

[0025] The RAN 110 can include one or more access nodes that enable the connections 103 and 104. These access nodes (ANs) can be referred to as base stations (BSs), NodeBs, evolved NodeBs (eNBs), Next Generation NodeBs (gNBs), RAN nodes, and the like, and can comprise ground stations (e.g., terrestrial access points) or satellite stations providing coverage within a geographic area (e.g., a cell). In some aspects, the communication nodes 111 and 112 can be transmission/reception points (TRPs). In instances when the communication nodes 111 and 112 are NodeBs (e.g., eNBs or gNBs), one or more TRPs can function within the communication cell of the NodeBs. The RAN 110 may include one or more RAN nodes for providing macrocells, e.g., macro RAN node 111, and one or more RAN nodes for providing femtocells or picocells (e.g., cells having smaller coverage areas, smaller user capacity, or higher bandwidth compared to macrocells), e.g., low power (LP) RAN node 112.

[0026] Any of the RAN nodes 111 and 112 can terminate the air interface protocol and can be the first point of contact for the UEs 101 and 102. In some aspects, any of the RAN nodes 111 and 112 can fulfill various logical functions for the RAN 110 including, but not limited to, radio network controller (RNC) functions such as radio bearer management, uplink and downlink dynamic radio resource management and data packet scheduling, and mobility management. In an example, any of the nodes 111 and/or 112 can be a gNB, an eNB, or another type of RAN node.

[0027] The RAN 110 is shown to be communicatively coupled to a core network (CN) 120 via an SI interface 113. In aspects, the CN 120 may be an evolved packet core (EPC) network, a NextGen Packet Core (NPC) network, or some other type of CN (e.g., as illustrated in reference to FIGS. IB-1C). In this aspect, the SI interface 113 is split into two parts: the Sl-U interface 114, which carries traffic data between the RAN nodes 111 and 112 and the serving gateway (S-GW) 122, and the Sl-mobility management entity (MME) interface 115, which is a signaling interface between the RAN nodes 111 and 112 and MMEs 121.

[0028] In this aspect, the CN 120 comprises the MMEs 121, the S-GW 122, the Packet Data Network (PDN) Gateway (P-GW) 123, and a home subscriber server (HSS) 124. The MMEs 121 may be similar in function to the control plane of legacy Serving General Packet Radio Service (GPRS) Support Nodes (SGSN). The MMEs 121 may manage mobility aspects in access such as gateway selection and tracking area list management. The HSS 124 may comprise a database for network users, including subscription-related information to support the network entities' handling of communication sessions. The CN 120 may comprise one or several HSSs 124, depending on the number of mobile subscribers, on the capacity of the equipment, on the organization of the network, etc. For example, the HSS 124 can provide support for routing/roaming, authentication, authorization, naming/addressing resolution, location dependencies, etc.

[0029] The S-GW 122 may terminate the SI interface 113 towards the RAN 110, and routes data packets between the RAN 110 and the CN 120. In addition, the S-GW 122 may be a local mobility anchor point for inter-RAN node handovers and also may provide an anchor for inter-3GPP mobility. Other responsibilities of the S-GW 122 may include a lawful intercept, charging, and some policy enforcement.

[0030] The P-GW 123 may terminate an SGi interface toward a PDN. The P-GW 123 may route data packets between the CN 120 and external networks such as a network including the application server 184 (alternatively referred to as application function (AF)) via an Internet Protocol (IP) interface 125. The P-GW 123 can also communicate data to other external networks 131 A, which can include the Internet, IP multimedia subsystem (IPS) network, and other networks. Generally, the application server 184 may be an element offering applications that use IP bearer resources with the core network (e.g., UMTS Packet Services (PS) domain, LTE PS data services, etc.). In this aspect, the P-GW 123 is shown to be communicatively coupled to an application server 184 via an IP interface 125. The application server 184 can also be configured to support one or more communication services (e.g., Voice-over-Internet Protocol (VoIP) sessions, PTT sessions, group communication sessions, social networking services, etc.) for the UEs 101 and 102 via the CN 120.

[0031 J The P-GW 123 may further be a node for policy enforcement and charging data collection. Policy and Charging Rules Function (PCRF) 126 is the policy and charging control element of the CN 120. In a non-roaming scenario, in some aspects, there may be a single PCRF in the Home Public Land Mobile Network (HPLMN) associated with a UE's Internet Protocol Connectivity Access Network (IP-CAN) session. In a roaming scenario with a local breakout of traffic, there may be two PCRFs associated with a UE's IP-CAN session: a Home PCRF (H-PCRF) within an HPLMN and a Visited PCRF (V-PCRF) within a Visited Public Land Mobile Network (VPLMN). The PCRF 126 may be communicatively coupled to the application server 184 via the P-GW 123.

[0032] In some aspects, the communication network 140 A can be an IoT network or a 5G or 6G network, including 5G new radio network using communications in the licensed (5G NR) and the unlicensed (5G NR-U) spectrum. One of the current enablers of IoT is the narrowband-IoT (NB-IoT). Operation in the unlicensed spectrum may include dual connectivity (DC) operation and the standalone LTE system in the unlicensed spectrum, according to which LTE-based technology solely operates in unlicensed spectrum without the use of an “anchor” in the licensed spectrum, called MulteFire. Further enhanced operation of LTE systems in the licensed as well as unlicensed spectrum is expected in future releases and 5G systems. Such enhanced operations can include techniques for sidelink resource allocation and UE processing behaviors for NR sidelink V2X communications. [0033] An NG system architecture (or 6G system architecture) can include the RAN 110 and a 5G core network (5GC) 120. The NG-RAN 110 can include a plurality of nodes, such as gNBs and NG-eNBs. The CN 120 (e.g., a

5G core network/5GC) can include an access and mobility function (AMF) and/or a user plane function (UPF). The AMF and the UPF can be communicatively coupled to the gNBs and the NG-eNBs via NG interfaces. More specifically, in some aspects, the gNBs and the NG-eNBs can be connected to the AMF by NG-C interfaces, and to the UPF by NG-U interfaces. The gNBs and the NG-eNBs can be coupled to each other via Xn interfaces. [0034] In some aspects, the NG system architecture can use reference points between various nodes. In some aspects, each of the gNBs and the NG- eNBs can be implemented as a base station, a mobile edge server, a small cell, a home eNB, and so forth. In some aspects, a gNB can be a master node (MN) and NG-eNB can be a secondary node (SN) in a 5G architecture.

[0035] FIG IB illustrates a non-roaming 5G system architecture in accordance with some aspects. In particular, FIG. 1B illustrates a 5G system architecture 140B in a reference point representation, which may be extended to a 6G system architecture. More specifically, UE 102 can be in communication with RAN 110 as well as one or more other 5GC network entities. The 5G system architecture 140B includes a plurality of network functions (NFs), such as an AMF 132, session management function (SMF) 136, policy control function (PCF) 148, application function (AF) 150, UPF 134, network slice selection function (NSSF) 142, authentication server function (AUSF) 144, and unified data management (UDM)/home subscriber server (HSS) 146.

[0036] The UPF 134 can provide a connection to a data network (DN) 152, which can include, for example, operator services, Internet access, or third- party services. The AMF 132 can be used to manage access control and mobility and can also include network slice selection functionality. The AMF 132 may provide UE-based authentication, authorization, mobility management, etc., and may be independent of the access technologies. The SMF 136 can be configured to set up and manage various sessions according to network policy. The SMF 136 may thus be responsible for session management and allocation of IP addresses to UEs. The SMF 136 may also select and control the UPF 134 for data transfer. The SMF 136 may be associated with a single session of a UE 101 or multiple sessions of the UE 101. This is to say that the UE 101 may have multiple 5G sessions. Different SMFs may be allocated to each session. The use of different SMFs may permit each session to be individually managed. As a consequence, the functionalities of each session may be independent of each other. [0037] The UPF 134 can be deployed in one or more configurations according to the desired service type and may be connected with a data network. The PCF 148 can be configured to provide a policy framework using network slicing, mobility management, and roaming (similar to PCRF in a 4G communication system). The UDM can be configured to store subscriber profiles and data (similar to an HSS in a 4G communication system).

[0038J The AF 150 may provide information on the packet flow to the PCF 148 responsible for policy control to support a desired QoS. The PCF 148 may set mobility and session management policies for the UE 101. To this end, the PCF 148 may use the packet flow information to determine the appropriate policies for proper operation of the AMF 132 and SMF 136. The AUSF 144 may store data for UE authentication.

[0039] In some aspects, the 5G system architecture 140B includes an IP multimedia subsystem (IMS) 168B as well as a plurality of IP multimedia core network subsystem entities, such as call session control functions (CSCFs).

More specifically, the IMS 168B includes a CSCF, which can act as a proxy CSCF (P-CSCF) 162BE, a serving CSCF (S-CSCF) 164B, an emergency CSCF (E-CSCF) (not illustrated in FIG. 1B), or interrogating CSCF (t-CSCF) 166B. The P-CSCF 162B can be configured to be the first contact point for the UE 102 within the IM subsystem (IMS) 168B. The S-CSCF 164B can be configured to handle the session states in the network, and the E-CSCF can be configured to handle certain aspects of emergency sessions such as routing an emergency request to the correct emergency center or PSAP. The I-CSCF 166B can be configured to function as the contact point within an operator's network for all IMS connections destined to a subscriber of that network operator, or a roaming subscriber currently located within that network operator's service area. In some aspects, the I-CSCF 166B can be connected to another IP multimedia network 170E, e.g. an IMS operated by a different network operator. [0040] In some aspects, the UDM/HSS 146 can be coupled to an application server 160E, which can include a telephony application server (TAS) or another application server (AS). The AS 160B can be coupled to the IMS 168B via the S-CSCF 164B or the I-CSCF 166B.

[0041] A reference point representation shows that interaction can exist between corresponding NF services. For example, FIG. 1B illustrates the following reference points: N1 (between the UE 102 and the AMF 132), N2 (between the RAN 110 and the AMF 132), N3 (between the RAN 110 and the UPF 134), N4 (between the SMF 136 and the UPF 134), N5 (between the PCF 148 and the AF 150, not shown), N6 (between the UPF 134 and the DN 152), N7 (between the SMF 136 and the PCF 148, not shown), N8 (between the UDM 146 and the AMF 132, not shown), N9 (between two UPFs 134, not shown), N10 (between the UDM 146 and the SMF 136, not shown), N11 (between the AMF 132 and the SMF 136, not shown), N12 (between the AUSF 144 and the AMF 132, not shown), N13 (between the AUSF 144 and the UDM 146, not shown), N14 (between two AMFs 132, not shown), N15 (between the PCF 148 and the AMF 132 in case of a non-roaming scenario, or between the PCF 148 and a visited network and AMF 132 in case of a roaming scenario, not shown), N16 (between two SMFs, not shown), and N22 (between AMF 132 and NSSF 142, not shown). Other reference point representations not shown in FIG. 1B can also be used.

[0042] FIG. 1C illustrates a 5G system architecture 140C and a service- based representation. In addition to the network entities illustrated in FIG. 1B, system architecture HOC can also include a network exposure function (NEF) 154 and a network repository function (NRF) 156. In some aspects, 5G system architectures can be service-based and interaction between network functions can be represented by corresponding point-to-point reference points Ni or as service-based interfaces.

[0043] In some aspects, as illustrated in FIG. 1C, service-based representations can be used to represent network functions within the control plane that enable other authorized network functions to access their services. In this regard, 5G system architecture HOC can include the following service- based interfaces: Namf 158H (a service-based interface exhibited by the AMF 132), Nsmf 1581 (a service-based interface exhibited by the SMF 136), Nnef 158B (a service-based interface exhibited by the NEF 154), Npcf 158D (a service-based interface exhibited by the PCF 148), aNudm 158E (a service- based interface exhibited by the UDM 146), Naf 158F (a service-based interface exhibited by the AF 150), Nnrf 158C (a service-based interface exhibited by the NRF 156), Nnssf 158A (a service-based interface exhibited by the NSSF 142), Nausf 158G (a service-based interface exhibited by the AUSF 144). Other service-based interfaces (e.g., Nudr, N5g-eir, and Nudsf) not shown in FIG. 1C can also be used.

[0044] NR-V2X architectures may support high-reliability low latency sidelink communications with a variety of traffic patterns, including periodic and aperiodic communications with random packet arrival time and size.

Techniques disclosed herein can be used for supporting high reliability in distributed communication systems with dynamic topologies, including sidelink NR V2X communication systems. [0045] FIG. 2 illustrates a block diagram of a communication device in accordance with some embodiments. The communication device 200 may be a UE such as a specialized computer, a personal or laptop computer (PC), a tablet PC, or a smart phone, dedicated network equipment such as an eNB, a server running software to configure the server to operate as a network device, a virtual device, or any machine capable of executing instructions (sequential or otherwise) that specify actions to be taken by that machine. For example, the communication device 200 may be implemented as one or more of the devices shown in FIGS. 1A-1C. Note that communications described herein may be encoded before transmission by the transmitting entity (e.g., UE, gNB) for reception by the receiving entity (e.g., gNB, UE) and decoded after reception by the receiving entity.

[0046] Examples, as described herein, may include, or may operate on, logic or a number of components, modules, or mechanisms. Modules and components are tangible entities (e.g., hardware) capable of performing specified operations and may be configured or arranged in a certain manner. In an example, circuits may be arranged (e.g., internally or with respect to external entities such as other circuits) in a specified manner as a module. In an example, the whole or part of one or more computer systems (e.g., a standalone, client or server computer system) or one or more hardware processors may be configured by firmware or software (e.g., instructions, an application portion, or an application) as a module that operates to perform specified operations. In an example, the software may reside on a machine readable medium. In an example, the software, when executed by the underlying hardware of the module, causes the hardware to perform the specified operations. [0047] Accordingly, the term “module” (and “component”) is understood to encompass a tangible entity, be that an entity that is physically constructed, specifically configured (e.g., hardwired), or temporarily (e.g., transitorily) configured (e.g., programmed) to operate in a specified manner or to perform part or all of any operation described herein. Considering examples in which modules are temporarily configured, each of the modules need not be instantiated at any one moment in time. For example, where the modules comprise a general-purpose hardware processor configured using software, the general-purpose hardware processor may be configured as respective different modules at different times. Software may accordingly configure a hardware processor, for example, to constitute a particular module at one instance of time and to constitute a different module at a different instance of time.

[0048] The communication device 200 may include a hardware processor (or equivalently processing circuitry) 202 (e.g., a central processing unit (CPU), a GPU, a hardware processor core, or any combination thereof), a main memory 204 and a static memory 206, some or all of which may communicate with each other via an interlink (e.g., bus) 208. The main memory 204 may contain any or all of removable storage and non-removable storage, volatile memory or non-volatile memory. The communication device 200 may further include a display unit 210 such as a video display, an alphanumeric input device 212 (e.g., a keyboard), and a user interface (UI) navigation device 214 (e.g., a mouse). In an example, the display unit 210, input device 212 and UI navigation device 214 may be a touch screen display. The communication device 200 may additionally include a storage device (e.g., drive unit) 216, a signal generation device 218 (e.g., a speaker), a network interface device 220, and one or more sensors, such as a global positioning system (GPS) sensor, compass, accelerometer, or other sensor. The communication device 200 may further include an output controller, such as a serial (e.g., universal serial bus (USB), parallel, or other wired or wireless (e.g., infrared (IR), near field communication (NFC), etc.) connection to communicate or control one or more peripheral devices (e.g., a printer, card reader, etc.).

[0049] The storage device 216 may include a non-transitory machine readable medium 222 (hereinafter simply referred to as machine readable medium) on which is stored one or more sets of data structures or instructions 224 (e.g., software) embodying or utilized by any one or more of the techniques or functions described herein. The instructions 224 may also reside, completely or at least partially, within the main memory 204, within static memory 206, and/or within the hardware processor 202 during execution thereof by the communication device 200. While the machine readable medium 222 is illustrated as a single medium, the term "machine readable medium" may include a single medium or multiple media (e.g., a centralized or distributed database, and/or associated caches and servers) configured to store the one or more instructions 224. [0050] The term “machine readable medium” may include any medium that is capable of storing, encoding, or carrying instructions for execution by the communication device 200 and that cause the communication device 200 to perform any one or more of the techniques of the present disclosure, or that is capable of storing, encoding or carrying data structures used by or associated with such instructions. Non-limiting machine readable medium examples may include solid-state memories, and optical and magnetic media. Specific examples of machine readable media may include: non-volatile memory, such as semiconductor memory devices (e.g., Electrically Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM)) and flash memory devices; magnetic disks, such as internal hard disks and removable disks; magneto-optical disks; Random Access Memory

(RAM); and CD-ROM and DVD-ROM disks. [0051] The instructions 224 may further be transmitted or received over a communications network using a transmission medium 226 via the network interface device 220 utilizing any one of a number of wireless local area network (WLAN) transfer protocols (e.g., frame relay, internet protocol (IP), transmission control protocol (TCP), user datagram protocol (UDP), hypertext transfer protocol (HTTP), etc.). Example communication networks may include a local area network (LAN), a wide area network (WAN), a packet data network (e.g., the Internet), mobile telephone networks (e.g., cellular networks), Plain

Old Telephone (POTS) networks, and wireless data networks. Communications over the networks may include one or more different protocols, such as Institute of Electrical and Electronics Engineers (IEEE) 802.11 family of standards known as Wi-Fi, IEEE 802.16 family of standards known as WiMax, IEEE 802.15.4 family of standards, a Long Term Evolution (LTE) family of standards, a Universal Mobile Telecommunications System (UMTS) family of standards, peer-to-peer (P2P) networks, a next generation (NG)/5^th generation (5G) standards among others. In an example, the network interface device 220 may include one or more physical jacks (e.g., Ethernet, coaxial, or phone jacks) or one or more antennas to connect to the transmission medium 226.

[0052J Note that the term “circuitry” as used herein refers to, is part of, or includes hardware components such as an electronic circuit, a logic circuit, a processor (shared, dedicated, or group) and/or memory (shared, dedicated, or group), an Application Specific Integrated Circuit (ASIC), a field-programmable device (FPD) (e.g., a field-programmable gate array (FPGA), a programmable logic device (PLD), a complex PLD (CPLD), a high-capacity PLD (HCPLD), a structured ASIC, or a programmable SoC), digital signal processors (DSPs), etc., that are configured to provide the described functionality. In some embodiments, the circuitry may execute one or more software or firmware programs to provide at least some of the described functionality. The term “circuitry” may also refer to a combination of one or more hardware elements (or a combination of circuits used in an electrical or electronic system) with the program code used to carry out the functionality of that program code. In these embodiments, the combination of hardware elements and program code may be referred to as a particular type of circuitry.

[0053] The term “processor circuitry” or “processor” as used herein thus refers to, is part of, or includes circuitry capable of sequentially and automatically carrying out a sequence of arithmetic or logical operations, or recording, storing, and/or transferring digital data. The term “processor circuitry” or “processor” may refer to one or more application processors, one or more baseband processors, a physical central processing unit (CPU), a single- or multi-core processor, and/or any other device capable of executing or otherwise operating computer-executable instructions, such as program code, software modules, and/or functional processes.

[0054] Any of the radio links described herein may operate according to any one or more of the following radio communication technologies and/or standards including but not limited to: a Global System for Mobile Communications (GSM) radio communication technology, a General Packet Radio Service (GPRS) radio communication technology, an Enhanced Data Rates for GSM Evolution (EDGE) radio communication technology, and/or a Third Generation Partnership Project (3 GPP) radio communication technology, for example Universal Mobile Telecommunications System (UMTS), Freedom of Multimedia Access (FOMA), 3 GPP Long Term Evolution (LTE), 3 GPP Long Term Evolution Advanced (LTE Advanced), Code division multiple access 2000 (CDMA2000), Cellular Digital Packet Data (CDPD), Mobitex, Third Generation (3G), Circuit Switched Data (CSD), High-Speed Circuit-Switched Data (HSCSD), Universal Mobile Telecommunications System (Third Generation) (UMTS (3G)), Wideband Code Division Multiple Access (Universal Mobile Telecommunications System) (W-CDMA (UMTS)), High Speed Packet Access (HSPA), High-Speed Downlink Packet Access (HSDPA), High-Speed Uplink Packet Access (HSUPA), High Speed Packet Access Plus (HSPA+), Universal Mobile Telecommunications System-Time-Division Duplex (UMTS-TDD), Time Division-Code Division Multiple Access (TD-CDMA), Time Division- Synchronous Code Division Multiple Access (TD-CDMA), 3rd Generation Partnership Project Release 8 (Pre-4th Generation) (3 GPP Rel. 8 (Pre-4G)), 3GPP Rel. 9 (3rd Generation Partnership Project Release 9), 3GPP Rel. 10 (3rd Generation Partnership Project Release 10) , 3GPP Rel. 11 (3rd Generation

Partnership Project Release 11), 3GPP Rel. 12 (3rd Generation Partnership Project Release 12), 3GPP Rel. 13 (3rd Generation Partnership Project Release 13), 3GPP Rel. 14 (3rd Generation Partnership Project Release 14), 3GPP Rel.

15 (3rd Generation Partnership Project Release 15), 3GPP Rel. 16 (3rd Generation Partnership Project Release 16), 3GPP Rel. 17 (3rd Generation Partnership Project Release 17) and subsequent Releases (such as Rel. 18, Rel. 19, etc ), 3 GPP 5G, 5G, 5G New Radio (5GNR), 3 GPP 5G New Radio, 3 GPP LTE Extra, LTE- Advanced Pro, LTE Licensed- Assisted Access (LAA), MuLTEfire, UMTS Terrestrial Radio Access (UTRA), Evolved UMTS Terrestrial Radio Access (E-UTRA), Long Term Evolution Advanced (4th Generation) (LTE Advanced (4G)), cdmaOne (2G), Code division multiple access 2000 (Third generation) (CDMA2000 (3G)), Evolution-Data Optimized or Evolution-Data Only (EV-DO), Advanced Mobile Phone System (1st Generation) (AMPS (1G)), Total Access Communication System/Extended Total Access Communication System (TACS/ETACS), Digital AMPS (2nd Generation) (D-AMPS (2G)), Push-to-talk (PTT), Mobile Telephone System (MTS), Improved Mobile Telephone System (IMTS), Advanced Mobile Telephone System (AMTS), OLT (Norwegian for Offentlig Landmobil Telefoni, Public Land Mobile Telephony), MTD (Swedish abbreviation for Mobiltelefonisystem D, or Mobile telephony system D), Public Automated Land Mobile (Autotel/PALM), ARP (Finnish for Autoradiopuhelin, "car radio phone"), NMT (Nordic Mobile Telephony), High capacity version of NTT (Nippon Telegraph and Telephone) (Hicap), Cellular Digital Packet Data (CDPD), Mobitex, DataTAC, Integrated Digital Enhanced Network (iDEN), Personal Digital Cellular (PDC), Circuit Switched Data (CSD), Personal Handy- phone System (PHS), Wideband Integrated Digital Enhanced Network (WIDEN), iBurst, Unlicensed Mobile Access (UMA), also referred to as also referred to as 3 GPP Generic Access Network, or GAN standard), Zigbee, Bluetooth(r), Wireless Gigabit Alliance (WiGig) standard, mm Wave standards in general (wireless systems operating at 10-300 GHz and above such as WiGig, IEEE 802.11ad, IEEE 802.11ay, etc.), technologies operating above 300 GHz and THz bands, (3GPP/LTE based or IEEE 802.1 lp or IEEE 802.1 lbd and other) Vehicle-to-Vehicle (V2V) and Vehicle-to-X (V2X) and Vehicle-to- Infrastructure (V2I) and Infrastructure-to- Vehicle (12 V) communication technologies, 3GPP cellular V2X, DSRC (Dedicated Short Range Communications) communication systems such as Intelligent-Transport-Systems and others (typically operating in 5850 MHz to 5925 MHz or above (typically up to 5935 MHz following change proposals in CEPT Report 71)), the European ITS-G5 system (i.e. the European flavor of IEEE 802. lip based DSRC, including ITS-G5A (i.e., Operation of ITS-G5 in European ITS frequency bands dedicated to ITS for safety re-lated applications in the frequency range 5,875 GHz to 5,905 GHz), ITS-G5B (i.e., Operation in European ITS frequency bands dedicated to ITS non- safety applications in the frequency range 5,855 GHz to 5,875 GHz), ITS-G5C (i.e., Operation of ITS applications in the frequency range

5,470 GHz to 5,725 GHz)), DSRC in Japan in the 700MHz band (including 715 MHz to 725 MHz), IEEE 802.1 lbd based systems, etc.

[0055] Aspects described herein can be used in the context of any spectrum management scheme including dedicated licensed spectrum, unlicensed spectrum, license exempt spectrum, (licensed) shared spectrum (such as LSA = Licensed Shared Access in 2.3-2.4 GHz, 3.4-3.6 GHz, 3.6-3.8 GHz and further frequencies and SAS = Spectrum Access System / CBRS = Citizen Broadband Radio System in 3.55-3.7 GHz and further frequencies). Applicable spectrum bands include IMT (International Mobile Telecommunications) spectrum as well as other types of spectrum/bands, such as bands with national allocation (including 450 - 470 MHz, 902-928 MHz (note: allocated for example in US (FCC Part 15)), 863-868.6 MHz (note: allocated for example in European Union (ETSI EN 300220)), 915.9-929.7 MHz (note: allocated for example in Japan), 917-923.5 MHz (note: allocated for example in South Korea), 755-779 MHz and 779-787 MHz (note: allocated for example in China), 790 - 960 MHz, 1710 - 2025 MHz, 2110 - 2200 MHz, 2300 - 2400 MHz, 2.4-2.4835 GHz (note: it is an ISM band with global availability and it is used by Wi-Fi technology family (1 lb/g/n/ax) and also by Bluetooth), 2500 - 2690 MHz, 698-790 MHz, 610 - 790 MHz, 3400 - 3600 MHz, 3400 - 3800 MHz, 3800 - 4200 MHz, 3.55-

3.7 GHz (note: allocated for example in the US for Citizen Broadband Radio Service), 5.15-5.25 GHz and 5.25-5.35 GHz and 5.47-5.725 GHz and 5.725-5.85 GHz bands (note: allocated for example in the US (FCC part 15), consists four U-NII bands in total 500 MHz spectrum), 5.725-5.875 GHz (note: allocated for example in EU (ETSI EN 301 893)), 5.47-5.65 GHz (note: allocated for example in South Korea, 5925-7125 MHz and 5925-6425MHz band (note: under consideration in US and EU, respectively. Next generation Wi-Fi system is expected to include the 6 GHz spectrum as operating band but it is noted that, as of December 2017, Wi-Fi system is not yet allowed in this band. Regulation is expected to be finished in 2019-2020 time frame), IMT-advanced spectrum, IMT-2020 spectrum (expected to include 3600-3800 MHz, 3800 - 4200 MHz, 3.5 GHz bands, 700 MHz bands, bands within the 24.25-86 GHz range, etc.), spectrum made available under FCC's "Spectrum Frontier" 5G initiative (including 27.5 - 28.35 GHz, 29.1 - 29.25 GHz, 31 - 31.3 GHz, 37 - 38.6 GHz, 38.6 - 40 GHz, 42 - 42.5 GHz, 57 - 64 GHz, 71 - 76 GHz, 81 - 86 GHz and 92 -

94 GHz, etc), the ITS (Intelligent Transport Systems) band of 5.9 GHz (typically 5.85-5.925 GHz) and 63-64 GHz, bands currently allocated to WiGig such as WiGig Band 1 (57.24-59.40 GHz), WiGig Band 2 (59.40-61.56 GHz) and WiGig Band 3 (61.56-63.72 GHz) and WiGig Band 4 (63.72-65.88 GHz), 57- 64/66 GHz (note: this band has near-global designation for Multi-Gigabit

Wireless Systems (MGWS)/WiGig . In US (FCC part 15) allocates total 14 GHz spectrum, while EU (ETSI EN 302567 and ETSI EN 301 217-2 for fixed P2P) allocates total 9 GHz spectrum), the 70.2 GHz - 71 GHz band, any band between 65.88 GHz and 71 GHz, bands currently allocated to automotive radar applications such as 76-81 GHz, and future bands including 94-300 GHz and above. Furthermore, the scheme can be used on a secondary basis on bands such as the TV White Space bands (typically below 790 MHz) where in particular the 400 MHz and 700 MHz bands are promising candidates. Besides cellular applications, specific applications for vertical markets may be addressed such as PMSE (Program Making and Special Events), medical, health, surgery, automotive, low-latency, drones, etc. applications.

[0056] Aspects described herein can also implement a hierarchical application of the scheme is possible, e.g., by introducing a hierarchical prioritization of usage for different types of users (e.g., low/medium/high priority, etc.), based on a prioritized access to the spectrum e.g., with highest priority to tier-1 users, followed by tier-2, then tier-3, etc. users, etc.

[0057] Aspects described herein can also be applied to different Single

Carrier or OFDM flavors (CP-OFDM, SC-FDMA, SC-OFDM, filter bank-based multicarrier (FBMC), OFDMA, etc.) and in particular 3GPP NR (New Radio) by allocating the OFDM carrier data bit vectors to the corresponding symbol resources.

[0058] Some of the features in this document are defined for the network side, such as APs, eNBs, NR or gNBs - note that this term is typically used in the context of 3GPP fifth generation (5G) communication systems, etc. Still, a UE may take this role as well and act as an AP, eNB, or gNB; that is some or all features defined for network equipment may be implemented by a UE.

[0059] FIG. 3 illustrates connection of a RAN node to two network slices simultaneously in accordance with some aspects. In FIG. 3, for subscription and configuration: UE A1 and A3 have a subscription to slice M, UE A2 and A3 have a subscription to slice N, and the applications of UE A3 are configured to use particular network slices. In FIG. 3, for deployment: Slice N and Slice M are isolated, the RAN is able to connect to both Slice M and Slice N, and Slice M and Slice N are provided by the same public land mobile network (PLMN). [0060] Based on 3GPP TS 23.501 and TS 38.300, the UE can access network slices based on information provided by the network during registration. Based on TS22.261 clause 6.1 network slicing, the 5G system allows the operator to assign a UE to a network slice, to move a UE from one network slice to another, and to remove a UE from a network slice based on subscription, UE capabilities, the access technology being used by the UE, operator's policies and services provided by the network slice. In addition, the 5G system enables a UE to be simultaneously assigned to and access services from more than one network slice of one operator. However, the UE may be unable to access or change the network slices when different network slices are used within the same operator’s network for active applications of the UE. That is, the above do not consider when the UE’s network slices are disjoint within one operator’s network as the UE does not have information to access the network slices based on its user preference and active applications, which result in latency and bad service experiences.

[0061] Accordingly, the network may provide assistance system information to allow the UEs to perform network slice-based cell-reselection. In particular, for a UE subscribing to multiple network slices that cannot be simultaneously provided to the UE: the 5G system provides the UE with the most suitable network slice of one operator (e.g., based on the ongoing applications, user preference); or supports change of provided network slices of one operator with minimized interruption e.g., when triggered by change of active applications and/or priorities.

[0062] Various solutions include the use of new information elements (IEs) with network slice related info in system information block 2 (SIB2), SIB3, SIB4, and SIB 5. In another solution, an on Demand SIB request for SIB info related to Slice/Service Type(s) (SST(s)) may be used for UEs in the RRC CONNECTED mode. In another solution, an on Demand SIB request for SIB information related to one or more SST(s) using a random access channel (RACH) procedure may be used for UEs in RRC_IDLE and RRCJNACTIVE mode.

[0063] As understood herein, the UE follows the cell re-selection procedure in 3 GPP TS 38.304 as well as the principles for network slicing based on 3 GPP TS 23.501. These principles include that a Single - Network Slice Selection Assistance Information (S-NSSAI) identifies a Network Slice. The S- NSSAI has: a Slice/Service type (SST), which refers to the expected Network Slice behaviour in terms of features and services; and a Slice Differentiator (SD), which is optional information that complements the SST(s) to differentiate amongst multiple Network Slices of the same SST. [0064] An S-NSSAI can have standard values (i.e., such a S-NSSAI may only contain an SST with a standardized SST value, see clause 5.15.2.2, and no SD) or non-standard values (i.e., such S-NSSAI may contain both an SST and an SD, or only an SST without a standardized SST value and no SD). An S-NSSAI with a non-standard value identifies a single Network Slice within the PLMN with which the S-NSSAI is associated. An S-NSSAI with a non-standard value is not used by the UE in access stratum procedures in any PLMN other than the one to which the S-NSSAI is associated.

[0065] Based on TS23.501, clause 5.15.2.2: Standardized SST value: Standardized SST values provide a way for establishing global interoperability for slicing so that PLMNs can support the roaming use case more efficiently for the most commonly used SSTs. The standardized SSTs are provided in the following Table 5.15.2.2-1.

Table 5.15.2.2-1 - Standardized SST values

[0066] The solutions are applicable and extendable for the standardized SST values that are defined in future releases. The solutions herein are for providing assistance information related to supported network slices in a SIB to the UE and allowing the UE to perform a cell-re-selection procedure within the same network of one operator.

[0067] Solution 1: new IEs with network slice related information in SIB2, SIB3, SIB4, and SIB5. In this solution, new IEs related to the network slice are provided in SIB2, SIB3, SIB4, SIB5 for allowing the UE to perform cell re-selection using the system information related to the SST based on the network slice of the active application and user preference.

[0068] As described in 3GPP TS 38.300, SIB2 contains cell re-selection information that is mainly related to the serving cell; SIB3 contains information about the serving frequency and intra-frequency neighboring cells relevant for cell re-selection (including cell re-selection parameters common for a frequency as well as cell specific re-selection parameters); SIB4 contains information about other NR frequencies and inter-frequency neighboring cells relevant for cell re- selection (including cell re-selection parameters common for a frequency as well as cell specific re-selection parameters); and SIB 5 contains information about E- UTRA frequencies and E-UTRA neighboring cells relevant for cell re-selection (including cell re-selection parameters common for a frequency as well as cell specific re-selection parameters).

[0069] Solutionl.l: network slice info in the System Information

Block (SIB2) [0070] Following solution 1, SIB 2 contains cell re-selection information common for intra-frequency, inter-frequency and/or inter-RAT cell re-selection (i.e., applicable for more than one type of cell re-selection but not necessarily all) as well as intra-frequency cell re-selection information other than neighboring cell related. In this solution, the frequencyBandList with corresponding SST type is added as IEs of intraFreqCellReselectionlnfo, e.g., frequencyBandList_SST1, frequencyBandList_SST2, frequencyBandList_SST4, frequencyBandList_SST4, etc. frequency BandList_SST1 MultiFrequencyBandListNR-SIB frequencyBandList_SST2 MultiFrequencyBandListNR-SIB frequencyBandList_SST3 MultiFrequencyBandListNR-SIB frequencyBandList_SST4 MultiFrequencyBandListNR-SIB

[0071] The frequencyBandList_SSTX indicates the list of frequency bands that support network slice with an SST for which the NR cell reselection parameters apply. Based on the user preference and the active applications, the UE uses a corresponding frequencyBandList_SSTX, wherein the SSTX can be SST1, SST2, SST3, SST4, etc. based on a standardized value.

[0072] If the network slice does not have a standardized value, the UE uses a frequencyBandList that does not provide a differentiation based on the supported network slice type. These solutions are applicable and extendable for the standardized SST values that are defined in future releases. [0073] Solution 1.2: network slice info in the System Information

Block (SIB3) [0074] Following solution 1, SIB3 contains neighboring cell-related information relevant only for intra-frequency cell re-selection. The IE includes cells with specific re-selection parameters as well as blacklisted cells. In this solution, the intraFreqNeighCellList_SSTX with corresponding SST type is added, e.g., intraFreqNeighCellList_SST1, IntraFreqNeighCellList_SST2, intraFreqNeighCellList_SST4, intraFreqNeighCellList_SST4, etc. intraFreqNeighCellList_SST1 IntraFreqNeighCellList intraFreqNeighCellList_SST2 IntraFreqNeighCellList intraFreqNeighCellList_SST3 IntraFreqNeighCellList intraFreqNeighCellList_SST4 IntraFreqNeighCellList

IntraFreqNeighCellList ::= SEQUENCE (SIZE (1..maxCellIntra)) OF IntraFreqNeighCelllnfo

IntraFreqNeighCelllnfo : := SEQUENCE {

- physCellld PhysCellld,

- q-OffsetCell Q-OffsetRange,

- q-RxLevMinOffsetCell INTEGER (1 .8) OPTIONAL, --NeedR q-RxLevMinOffsetCell SUL INTEGER (1..8) OPTIONAL, --Need R q-QualMinOffsetCell INTEGER (1 .8) OPTIONAL, --Need R

}

[0075] The intraFreqNeighCellList_SSTX indicates a list of intra- frequency neighboring cells that support a network slice with a specific SST and with specific cell re-selection parameters. Based on the user preference and the active applications, the UE uses a corresponding intraFreqNeighCellList_SSTX. The SSTX can be SST1, SST2, SST3, SST4, etc. based on a standardized value. [0076] If the network slice does not have a standardized value, the UE uses an IntraFreqNeighCellList that does not provide differentiation based on a supported network slice type. The solutions are applicable and extendable for the standardized SST values that are defined in future releases.

[0077] Solution 1.3: network slice info in the System Information

Block (SIB4) [0078] Following solution 1, SIB4 contains information relevant only for inter-frequency cell re-selection, i.e., information about other NR frequencies and inter-frequency neighboring cells relevant for cell re-selection. The IE includes cell re-selection parameters common for a frequency as well as cell specific re-selection parameters.

[0079J In this solution, for interFreqCarrierFreqList with structure of

InterFreqCarrierFreqlnfo, the following new IEs are used:

- the frequencyBandList with corresponding SST type is added as new IEs of, e.g., frequencyBandList_SST1, frequencyBandList_SST2, frequencyBandList_SST4, frequencyBandList_SST4, etc. frequencyBandList_SST1 MultiFrequencyBandListNR-SIB frequencyBandList_SST2 MultiFrequencyBandListNR-SIB frequency BandList_SSTS MultiFrequencyBandListNR-SlB frequencyBandList_SST4 MultiFrequencyBandListNR-SIB

[0080] The frequencyBandList_SSTX indicates the list of frequency bands that support a network slice with a specific SST for which the NR cell reselection parameters apply. Based on the user preference and the active applications, the UE uses a corresponding frequencyBandList_SSTX. The SSTX can be SST1, SST2, SST3, SST4, etc. based on a standardized value. [0081] If the network slice does not have a standardized value, the UE uses a frequencyBandList that does not provide differentiation based on supported network slice type. the interFreqNeighCellList_SSTX with corresponding SST type is added, e.g., interFreqNeighCellList_SST1 , interFreqNeighCellList_SST2, interFreqNeighCellList_SST4, interFreqNeighCellList_SST4, etc. interFreqNeighCellList_SST1 InterFreqNeighCellList interFreqNeighCellList_SST2 InterFreqNeighCellList interFreqNeighCellList_SST3 InterFreqNeighCellList interFreqNeighCellList_SST4 InterFreqNeighCellList

InterFreqNeighCellList ::= SEQUENCE (SIZE (1..maxCelllnter)) OF InterFreqNeighCelllnfo

InterFreqNeighCelllnfo ::= SEQUENCE { physCellld PhysCellld, q-OffsetCell Q-OffsetRange,

- q-RxLevMinOffsetCell INTEGER (1..8) OPTIONAL, --

Need R q-RxLevMinOffsetCellSULINTEGER (1. 8) OPTIONAL, — Need R

} [0082] The interFreqNeighCellList_SSTX indicates a list of intra- frequency neighboring cells that support a network slice with a specific SST and with specific cell re-selection parameters. Based on the user preference and the active applications, the UE uses a corresponding interFreqNeighCellList_SSTX. The SSTX can be SST1, SST2, SST3, SST4, etc. based on a standardized value. [0083] If the network slice does not have a standardized value, the UE uses an interFreqNeighCellList_SSTX that does not provide differentiation based on a supported network slice type. The solutions are applicable and extendable for the standardized SST values that are defined in future releases.

[0084] Solution 1.4: network slice info in the System Information

Block (SIBS) [0085] Following solution 1, SIBS contains information relevant only for inter-RAT cell re-selection i.e., information about E-UTRA frequencies and E- UTRAs neighboring cells relevant for cell re-selection. The IE includes cell re- selection parameters common for a frequency.

[0086] In this solution, for CarrierFreqEUTRA, the following IEs are used: the eutra-multiBandlnfbList with corresponding SST type is added as new IEs of, e.g. eutra-multiBandlnfoList_SST1 , eutra-multiBandInfoList_SST2, eutra-multiBandInfoList_SST4, eutra-multiBandlnfoList_S-ST4, etc. eutra-multiBandlnfoList_SST1 EUTRA-MultiBandlnfoList

- eutra-multiBandlnfoList_SST2 EUTRA-MultiBandlnfoList eutra-multiBandInfoList_SST3 EUTRA-MultiBandlnfoList

- eutra-multiBandlnfoList_SST4 EUTRA-MultiBandlnfoList

[0087] The eutra-multiBandlnfoList_SSTX indicates the list of frequency bands that support a network slice with a specific SST for which the NR cell reselection parameters apply. Based on the user preference and the active applications, the UE uses a corresponding eutra- multiBandlnfoList_SSTX. The SSTX can be SST1, SST2, SST3, SST4, etc. based on a standardized value.

[0088] If the network slice does not have a standardized value, the UE uses an eutra-multiBandlnfoList that does not provide differentiation based on a supported network slice type. The eutra-FreqNeighCellList_SSTX with corresponding SST type is added, e.g., eutra-FreqNeighCellList_SST1, eutra- FreqNeighCellList_SSTZ, eutra-FreqNeighCellList_SST4, eutra- FreqNeighCellList_SST4, etc.

- eutra-FreqNeighCellList_SST1 EUTRA-FreqNeighCellList

- eutra-FreqNeighCellList_SST2 EUTRA-FreqNeighCellList

- eutra-FreqNeighCellList_SST3 EUTRA-FreqNeighCellList

- eutra-FreqNeighCellList_SST4 EUTRA-FreqNeighCellList

EUTRA-FreqNeighCellList : := SEQUENCE (SIZE (1..maxCellEUTRA)) OF EUTRA-FreqNeighCelllnfo

EUTRA-FreqNeighCell Info ::= SEQUENCE { - physCellld EUTRA-Phy sC ellld, - dummy EUTRA-Q-OffsetRange, - q-RxLevMinOffsetCell INTEGER (1 .8) OPTIONAL, --NeedR - q-QualMinOffsetCell INTEGER (1..8) OPTIONAL --Need R

}

[0089] The eutra-FreqNeighCellList_SSTX indicates list of E-UTRA frequencies of neighboring cells that support network slice with a specific SST and with specific cell re-selection parameters. Based on the user preference and the active applications, the UE uses a corresponding eutra- FreqNeighCellListSSTX. The SSTX canbe SST1, SST2, SST3, SST4, etc. based on a standardized value.

[0090] If the network slice does not have a standardized value, the UE uses an eutra-FreqNeighCellList that does not provide differentiation based on a supported network slice type. The solutions are applicable and extendable for the standardized SST values that are defined in future releases.

[0091] Solution 2: on Demand SIB request for SIB info related to required SST(s) [0092] Following solution 1.1, 1.2, 1.3, 1.4 for SIB2, SIB3, SIB4, SIB5, for a UE in RRC_ CONNECTED mode, this solution allows the UE to send an on Demand SIB request for SIB2/SIB3/SIB4/SIB5 with the requested SST(s). The gNB can respond with the requested SIB(s) with requested network slice information in a dedicated or broadcasted manner.

[0093] The UE sets the contents of DedicatedSIBRequest message with a requestedSST IE to indicate the requested SIB information related to the requested SST of the network slices as follows:

1>if the procedure is triggered to request the required SIB(s): 2> include requestedSIB-List and requestedSST-List in the onDemandSIB- RequestList to indicate the requested SIB(s) and requested SST(s);

DedicatedSIBRequest-IEs ::= SEQUENCE { onDemandSIB-RequestList SEQUENCE { requestedSIB-List_SEQUENCE (SIZE (1..maxOnDemandSIB)) OF SIB-

Reqlnfo OPTIONAL. requestedSST-List SEQUENCE (SIZE (1..maxSST)) OF ServcieSliceType-

Reqlnfo OPTIONAL.

} OPTIONAL, lateNonCriticalExtension OCTET STRING OPTIONAL, nonCriticalExtension SEQUENCE {} OPTIONAL

} SIB-Reqlnfo ::= ENUMERATED { sib 12, sib13, sib 14, sib2, sib3, sib4, sib5, spare1 }

ServiceSliceType-Reqlnfo ::= ENUMERATED { SST1, SST2, SST3, SST4, spare4, spare3, spare2, spare1 } [0094] For UE information related to a network slice with a specific SST, the UE submits a DedicatedSIBRequest message including requestedSIB- List and requestedSST-List to lower layers for transmission.

[0095] FIG. 4 illustrates SI provisioning in accordance with some aspects. [0096] For UEs in RRC_ CONNECTED mode, a request for Other SI may be sent to the network, if configured by the network, in a dedicated manner (i.e., via UL-DCCH message including DedicatedSIBRequest IE) and the granularity of the request is one SIB.

[0097] The gNB may respond with an RRCReconfiguralion including the requested SIB(s) in the following IEs. It is a network choice to decide which requested SIBs are delivered in a dedicated or broadcasted manner.

[0098] The dedicated SIBs include the requested network slice information as indicated in solution 1.1, solution 1.2, solution 1.3, solution 1.4 for SIB2, SIB3, SIB4, SIBS, respectively. For example, if SIB-Reqlnfo ::= sib2 and ServiceSliceType-Reqlnfo ::= SST2 are requested, the network provides system information for SIB2 with intraFreqCellReselectionlnfo indicating frequencyBandList_SST2. For example, if SIB-Reqlnfo ::= sib2 and ServiceSliceType-ReqInfo ::= SST2 and SST4 are requested, the network provides system information for SIB2 with intraFreqCellReselectionlnfo indicating frequencyBandList_SST2 and frequencyBandList_SST4. In this case, the UE determines its preference to use frequencyBandList_SST2 and/or frequencyBandList_SST4 for cell re-selection. For example, if SIB-Reqlnfo ::= sib4 and ServiceSliceType-Reqlnfo ::= SST2 are requested, the network provides system information for SIB4 with interFreqCellReselectionlnfo indicating frequencyBandList_SST2.

[0099] Solution 3: on Demand SIB request for SIB info related to required SST(s) using RACH procedure

[00100] Following solution 1.1, 1.2, 1.3, 1.4 for SIB2, SIB3, SIB4, SIB5, for a UE in RRC_IDLE and RRC_INACTIVE mode, this solution allows the UE to request on Demand SIB for SIB2/SIB3/SIB4/SIB5 with requested SST(s). [00101] From 3 GPP TS 38.311: if SIB1 includes si-Schedulinglnfo containing si-RequestConfig and criteria to select normal uplink as defined in TS 38.321, clause 5.1.1 is met, UEs in RRC_ IDLE and RRC_ INACTIVE mode send a request for Other SI triggers in the lower layer that initiates a random access procedure (TS 38.300, clause 9.2.6) in accordance with TS 38.321 using the PRACH preamble(s) and PRACH resource(s) in si-RequestConfig corresponding to the SI message(s) that the UE uses to operate within the cell, and for which si-BroadcastStatus is set to notBroadcasting. When the UE receives acknowledgement for the SI request from the lower layers, the UE acquires the requested SI message(s).

[00102] In the RACH procedure, the MSG3 includes the SI request message unless the requested SI is associated to a subset of the PRACH resources, in which case MSG1 is used for indication of the requested Other SI. [00103] When MSG1 is used, the minimum granularity of the request is one SI message (i.e., a set of SIBs), one RACH preamble and/or PRACH resource can be used to request multiple SI messages and the gNB acknowledges the request with requested SIB including requested network slice related info in MSG2. [00104] When MSG 3 is used to send DedicatedSIBRequest message, the gNB acknowledges the request with requested SIB including requested network slice related info in MSG4.

[00105] FIG. 5 illustrates a Random Access procedure in accordance with some aspects.

[00106] In this solution, an IE, sstOption, is added in sib-Mappinglnfo to indicate the SIB-Typelnfo with SIB type (including sibType2, sibType3, etc.) and sstOption in the corresponding sibType. For example, if sstOption is set to 2, the SIB contains network slice information related to SST=2 as indicated in solution 1.1, 1.2, 1.3, 1.4 for SIB2, SIB3, SIB4, SIB5. For example, if sstOption is set to 2 and 4, the SIB contains network slice information related to SST=2 and SST=4 as indicated in solution 1.1, 1.2, 1.3, 1.4 for SIB2, SIB3, SIB4, SIB5. [00107] The details are as shown in the Sl-Schedulinglnfo information element as follows: the IE Sl-Schedulinglnfo contains information for acquisition of SI messages.

Sl-Schedulinglnfo information element --ASNl START -- TAG-SI-SCHEDULINGINFO-START Sl-Schedulinglnfo ::= SEQUENCE { schedulinglnfoList SEQUENCE (SIZE (1..maxSI-Message)) OF

Schedulinglnfo, si-WindowLength ENUMERATED {s5, s10, s20, s40, s80, si 60, s320, s640, s1280}, si-RequestConfig SI-RequestConfig OPTIONAL, — Cond MSG-1 si -RequestConfigSUL SI-RequestConfig OPTIONAL, -- Cond SUL-

MSG-1 systemMormationArealD BIT STRING (SIZE (24)) OPTIONAL, --Need

R

}

Schedulinglnfo ::= SEQUENCE { si-BroadcastStatus ENUMERATED (broadcasting, notBroadcasting} , si-Periodicity ENUMERATED (rf8, rf16, rf32, rf64, rfl28, rf256, rf512}, sib-Mappinglnfo SIB-Mapping

} SIB-Mapping : := SEQUENCE (SIZE (L.maxSIB)) OF SIB-Typelnfo SIB-Typelnfo ::= SEQUENCE { type NUMERATED { sibType2. sibType3. sibType4. sibType5. sibType6, sibType7, sibType8, sibType9, sibType10-v1610, sibTypell-v1610, sibType12-v1610, sibType13-v1610, sibTypel4-v1610, spare3, spare2, spare1,... }, sstOption INTEGER (0..X) OPTIONAL, -- Cond SIB-TYPE valueTag INTEGER (0..31) OPTIONAL, - Cond SIB-TYPE areaScope ENUMERATED {true} OPTIONAL -- Need S

}

- TAG-SI-SCHEDULINGINFO-STOP --ASNISTOP

[00108] The IE SI-RequestConfig contains configuration for a Msgl- based SI request. SI-RequestConfig: := SEQUENCE { rach-OccasionsSI SEQUENCE { rach-ConfigSI R ACH-Confi gGeneric, ssb-perRACH-Occasion ENUMERATED {oneEighth, oneFourth, oneHalf, one, two, four, eight, sixteen}

} OPTIONAL, — Need R si-RequestPeriod ENUMERATED {one, two, four, six, eight, ten, twelve, sixteen

} OPTIONAL, — Need R si-RequestResources SEQUENCE (SIZE (1..max Si-Message)) OF SI-

RequestResources

}

SI-RequestResources ::= SEQUENCE { ra-PreambleStartlndex INTEGER (0..63), ra-AssociationPericxilndex INTEGER (0..15) OPTIONAL, --Need R ra-ssb-OccasionMasklndex INTEGER (0..15) OPTIONAL --Need R

}

[00109] Thus, in various embodiments SIB2 contains cell re-selection information common for intra-frequency, inter-frequency and/or inter-RAT cell re-selection (i.e., applicable for more than one type of cell re-selection but not necessarily all) as well as intra-frequency cell re-selection information other than neighboring cell related. SIB2 contains IEs of frequencyBandList with corresponding SST type, added as new IEs of intraFreqCellReselectionlnfo, e.g. frequencyBandList_SST1, frequencyBandList_SST2, frequencyBandList_SST4, ffequencyBandList_SST4, etc. SIB3 contains neighboring cell related information relevant only for intra-frequency cell re-selection and the IE includes cells with specific re-selection parameters as well as blacklisted cells. [00110] In 5G, network slicing has been supported since release 15. The existing solutions do not consider that the UE’s required network slices are disjoint within one operator’s network. The UE does not have information to access the network slices based on its user preference and active applications, which result in latency and bad service experiences. Considering enhanced access to and support of network slices, in 3GPP TR 22.835, FIG. 6 illustrates a roaming UE with service on network slices available on different networks in accordance with some aspects. [00111] Use Case A, for 3GPP TR 22.835 clause 5.5, the use case considers that the UE uses different network slices of different operators in- simultaneously (at different time) as follows:

[00112] A UE subscribes to multiple network slices from its home operator. The home operator has agreements with various other operators to support the same slices for roaming UEs. In this case, the most preferred visiting PLMN (VPLMN) in a specific area does not support all the desired slices; however, a second VPLMN does support the slice not available in the most preferred VPLMN. In this case, the home operator can provide the information to allow the UE to use the second VPLMN to obtain the service available on that network slice, while otherwise being served by the most preferred VPLMN.

[00113] As shown in FIG. 6, when UE A first enters the visited area, UE A registers with Network A and can uses services from slice N.

[00114] At a later time (T2), the user decides to activate a service that uses slice M. The UE, detecting that slice M is not available on Network A, looks for the network that provides the slice. The UE registers on Network B and the user is able to use the service of slice M.

[00115] When the service concludes and slice M is no longer to be used (T3), the UE returns to Network A if still used for the slice N. [00116] Use Case B, for 3GPP TR 22.835 clause 5.6, the use case considers that the UE uses the network slices of different operators simultaneously (at the same time): A UE has access to multiple network slices when on the HPLMN. When the UE is roaming and the VPLMN the UE is currently registered on only provides a subset of the network slices that the UE is to use, the UE can connect to another VPLMN at the same time to access the other slices.

[00117] As shown in FIG. 6, when UE A first enters the visited area, UE A registers with Network A and can uses services from slice N. At a later time (T2), the user decides to activate a service that uses slice M. The UE, detecting that slice M is not available on Network A, finds the network B that provides the slice M. While keeping the slice N of the Network A, the UE accesses Network B for using the service of slice M. The UE can use slice N of network A and slice M of network B at the same time. [00118] When the service concludes and slice M is no longer needed (T3), the UE stop using slice N of network B and continue to use slice M of Network

A.

[00119] Based on service requirements of steering of roaming in 3GPP TS

22.011 and 3GPP TS 22.261 and based on solutions of steering of roaming in 3GPP TS 23.122, solutions are provided for fulfilling the following:

[00120] When a roaming UE desires a network slice not offered by the serving network but available in the area from another network, the HPLMN shall be able to steer the UE to the other network and back to the previous network when the network slice is no longer in use. [00121] The 5G system shall enable a roaming UE with a single PLMN subscription to access network slices from two VPLMNs simultaneously, when the UE is to use simultaneous access to two network slices and the network slices are not available in a single network.

[00122] The HPLMN shall be able to authorize a roaming UE with a single PLMN subscription to access network slices from two VPLMNs simultaneously.

[00123] The HPLMN shall be able to provide a UE with permission and prioritization information of the VPLMNs the UE is authorized to use for accessing specific network slices. [00124] NOTE: the above depend on certain UE capabilities assumptions, e.g. the ability to connect to two PLMNs simultaneously.

[00125] Accordingly, the following solutions enhance disjoint network slices with one or more operators. [00126] Solution 1 : include network slices information in Steering of

Roaming (SoR) info, i.e. Operator Controlled PLMN Selector with Access Technology and network slices" list. This is to resolve use case A and use case B and fulfill the corresponding service requirements.

[00127] Solution 2: allow skipping SD information of an S-NSSAI. [00128] Solutions: resolve the issues for the use case A and fulfil the corresponding service requirements. This solution is for the UE uses the same radio access technology (RAT) in the first and second PLMN.

[00129] Solution 4: resolve the issues for the use case B and fulfil the corresponding service requirements. It allows the UE for using different RATs to register with the first and second PLMNs for their different network slices simultaneously.

[00130] Background:

[00131] 3GPP TS 22.011: subclause 3.2.2.8

[00132] 3GPP TS 22.261: subclause 6.30 for SoR and 6.1 for network slicing

[00133] 3GPP TS 23.122:

[00134] The purpose of the control plane solution for steering of roaming in 5GS procedure is to allow the HPLMN to update the "Operator Controlled PLMN Selector with Access Technology" list in the UE by providing the HPLMN protected list of preferred PLMN/access technology combinations via NAS signalling.

[00135] If the selected PLMN is a VPLMN, the HPLMN can provide the steering of roaming information to the UE using the control plane mechanism during and after registration. [00136] If the selected PLMN is the HPLMN, the HPLMN can provide the steering of roaming information to the UE using the control plane mechanism after registration only. [00137] The HPLMN updates the "Operator Controlled PLMN Selector with Access Technology" based on the operator policies, which can be based on the registered VPLMN, the location of the UE, etc.

[00138] The HPLMN can configure their subscribed UE's universal subscriber identity module (USIM) to indicate that the UE is expected to receive the steering of roaming information due to initial registration in a VPLMN. [00139] The UE supporting N1 mode shall support the control plane solution for steering of roaming in 5GS. If the HPLMN supports and wants to use the control plane solution for steering of roaming in 5GS, then the HPLMN shall provide the steering of roaming information to the UE using the control plane mechanism defined in this annex.

[00140] The VPLMN shall transparently relay the steering of roaming information received from the HPLMN to the UE.

[00141] The UE shall be able to detect whether the VPLMN removed the steering of roaming information during the initial registration procedure in the

VPLMN.

[00142] The UE shall be able to detect whether the VPLMN altered the steering of roaming information. If the UE detects that the VPLMN altered or removed the steering of roaming information then the UE shall consider the current VPLMN as the lowest priority PLMN and perform PLMN selection as defined in this annex.

[00143] If: the UE's USIM is configured to indicate that the UE shall expect to receive the steering of roaming information during initial registration procedure but did not receive it or security check on the steering of roaming information fails; the current chosen VPLMN is not contained in the list of "PLMNs where registration was aborted due to SOR"; the current chosen VPLMN is not part of "User Controlled PLMN Selector with Access Technology" list; and the UE is not in manual mode of operation; then the UE will perform PLMN selection with the current VPLMN considered as lowest priority.

[00144] It is mandatory for the VPLMN to transparently forward to the UE the steering of roaming information received from HPLMN and to transparently forward to the HPLMN the acknowledgement of successful reception of the steering of roaming information received from UE, both while the UE is trying to register onto the VPLMN, and after the UE has registered onto the VPLMN.

[00145] The procedure for steering of UE in VPLMN can be initiated by the network while the UE is trying to register onto the VPLMN, or after the UE has registered onto the HPLMN or the VPLMN.

[00146] C.2 Stage-2 flow for steering of UE in VPLMN during registration

[00147] FIG. 7 illustrates a procedure to provide a list of preferred public land mobile network (PLMN)/access technology combinations in accordance with some aspects. The stage-2 flow for the case when the UE registers with VPLMN AMF is described in FIG. 7. The selected PLMN is the VPLMN. The AMF is located in the selected VPLMN.

[00148] C.3 Stage-2 flow for steering of UE in HPLMN or VPLMN after registration [00149] FIG. 8 illustrates a procedure to provide a list of preferred

PLMN/access technology combinations after registration in accordance with some aspects. The stage-2 flow for the steering of UE in HPLMN or VPLMN after registration is indicated in FIG. 8. The selected PLMN can be the HPLMN or a VPLMN. The AMF is located in the selected PLMN. The flow is triggered: if the HPLMN UDM supports obtaining a list of preferred PLMN/access technology combinations or a secured packet from the SOR-AF, the HPLMN policy for the SOR-AF invocation is present in the HPLMN UDM and the SOR- AF provides the HPLMN UDM with a new list of preferred PLMN/access technology combinations or a secured packet for a UE identified by SUPI; or when a new list of preferred PLMN/access technology combinations or a secured packet becomes available in the HPLMN UDM.

[00150] The solutions are based on the following two assumptions: [00151] A. The UE can obtain steering of roaming information based on SoR procedures in 3GPP TS 22.122 with new additions. For Steering of Roaming: the SOR list includes PLMN and access technology combination, an indication of received report is present, and two flows exist: a UE triggered update of SOR during registration procedure or a SOR-AF triggered update after registration. [00152] B. the UE and the network follows the following principles for network slicing based on 3GPP TS 23.501:

[00153] An S-NSSAI identifies a Network Slice.

[00154] An S-NSSAI includes: an SST and a SD. [00155] An S-NSSAI can have standard values (such an S-NSSAI only includes an SST with a standardized SST value, see clause 5.15.2.2, and no SD) or non-standard values (such S-NSSAI includes either both an SST and an SD or only an SST without a standardized SST value and no SD). An S-NSSAI with a non-standard value identifies a single Network Slice within the PLMN with which the S-NSSAI is associated. An S-NSSAI with a non-standard value shall not be used by the UE in access stratum procedures in any PLMN other than the one to which the S-NSSAI is associated.

[00156] Further, based on 3GPP TS 23.501, clause 5.15.2.2: Standardized SST value [00157] Standardized SST values provide a way for establishing global interoperability for slicing so that PLMNs can support the roaming use case more efficiently for the most commonly used Slice/Service Types. The SSTs that are standardized are in the Table 5.15.2.2-1.

Table 5.15.2.2-1 - Standardized SST values

Slice/Service SST Characteristics type value eMBB 1 Slice suitable for the handling of 5G enhanced Mobile Broadband.

URLLC 2 Slice suitable for the handling of ultra- reliable low latency communications.

MIoT 3 Slice suitable for the handling of massive IoT.

V2X 4 Slice suitable for the handling of V2X services.

[00158] The solutions are applicable and extendable for the standardized SST values that are defined in future releases. Solutions 0-4 above enhance disjoint network slices with one or more operators. [00159] Solution 0: new service requirements

[00160] The following service requirements are used:

[00161] For Use case A, [New-Al]: When a roaming UE is to use a network slice not offered by the serving network but available in the area from another network, the HPLMN shall be able to steer the UE to the other network and initiates higher priority PLMN selection based on the type of network slice for ongoing or resuming application when the network slice is no longer in use. [00162] For Use case B, [New-B1] The 5G system shall enable a UE with a single PLMN subscription to access network slices from HPLMN and another VPLMN simultaneously, when the UE is to use simultaneous access to two networks and the network slices are not available in a single network.

[00163] For Use case B, [New-B2] The 5G system shall support a mechanism for the HPLMN to control the timing when a UE with a single PLMN subscription registered on HPLMN or VPLMN, in automatic mode (see clause 3.1 of 3GPP TS 23.122) and currently in CONNECTED mode, and initiates higher priority PLMN selection for another VPLMN to access network slices from two PLMNs simultaneously based on the type of network slices for ongoing applications. [00164] Solutionl: SoR list with additional network slices info

[00165] The registered AMF can provide an SoR list, "Operator Controlled PLMN Selector with Access Technology and network slices" list, in which an associated S-NSSAI(s) is provided for each PLMN based on the UE’s subscription information related to subscribed S-NSSAI(s) during the registration procedure.

[00166] Two SoR list options are available:

[00167] 1) one SoR list that contains VPLMN information of the

VPLMNs with Access Technologies and supported S-NSSAI(s) combination [00168] 2) multiple SoR lists in which each SoR list has VPLMN information with Access Technologies and associated S-NSSAI.

[00169] The UE stores the SoR list that contains "Operator Controlled PLMN Selector with Access Technology and network slices" list.

[00170] Solution 1.1: indication of skipping SD [00171] Following solution 1 , the SoR list includes Operator Controlled

PLMN Selector with Access Technology and network slices, which is the preferred PLMN/access technology/S-N S S AI(s) combinations. [00172] This list also contains an indication of skipping the SD in each S- NSSAI. If this indication is active, the UE can select the VPLMN with the desired SST in a S-NSSAI without considering SD information of the S-NSSAI. [00173] Solution 1.2: registration update

[00174] Following solution 1 or 1.1, when the UE is to change network slices that are with different S-NSSAI(s) and are not currently supported from its current registration of the first PLMN, the UE initiates a registration procedure with a registration type indicating the mobility registration update.

[00175] Solution 1.3:

[00176] Following solution 1.2, the registration request message can provide additional information to trigger the procedure to update the SoR list with the following options: [00177] 1) include an indicator for SoR with network slices indicator for updating the SoR list that contains VPLMN information with Access Technologies and supported S-NSSAI(s) combination. This is used for the case with only one SoR list as indicated in Solution 1.

[00178] 2) include a new IE indicating one or more S-NSSAI(s) of the network slices to be used. This is used for multiple SoR lists in which each SoR list has VPLMN information with Access Technologies and associated S- NSSAI, as indicated in Solution 1.

[00179] Solution 1.4: [00180] Following solution 1.3, the 5G network performs a procedure based on the current registered PLMN of the UE:

[00181] If the current registered network is the HPLMN, the HPLMN

AMF provides updates of the SoR list, i.e., "Operator Controlled PLMN Selector with Access Technology and network slices list, via NAS signaling to the UE. [00182] If the current registered network is a VPLMN, the VPLMN AMF includes an indicator for updating SoR list or a new IE indicating one or more S- NSSAI(s) of the desired network slices in the Nudam SDM Get request message to the HPLMN UDM and the indication is forwarded by the HPLMN UDM to the SOR-AF in the Nsoraf SoR Obtain request message. [00183] In responding to Nsoraf SoR Obtain request message, the following procedure is performed: the SOR-AF may provide updates of an SoR list with all information or one or more lists with different associated S- NSSAI(s) in the Nsoraf SoR Obtain response message to HPLMN UDM. The information is forwarded by the VPLMN UDM to the VPLMN AMF. The VPLMN AMF provides updates of the "Operator Controlled PLMN Selector with Access Technology and network slices" list via NAS signaling to the UE.

[00184] Solution 1.5: [00185] FIG. 9 illustrates a procedure to provide a list of preferred

PLMN/access technology combinations in accordance with some aspects. Following solution 1.4, according to the existing registration procedure in 3GPP TS 23.122 clause C.2.1 and FIG. 9, in this solution the UE can initiate the registration procedure with the following additions for the SoR list of "Operator Controlled PLMN Selector with Access Technology and network slices" :

[00186] The procedure can also be initiated for the UE that is to change network slices that have different slice/service type(s) or S-NSSAI(s) and are not currently supported from the current registration of the first PLMN provided by operator A. [00187] In FIG. 9, step 1 : the UE initiates the registration procedure with a registration type indicating a mobility registration update and an SoR for network slices indicator IE or a new IE indicating one or more S-NSSAI(s) of the network slices for SOR information. With the indication, the HPLMN/VPLM AMF triggers the update of SoR list from the HPLMN during the registration procedure.

[00188] Step 2: if the UE is currently registered at the VPLMN, the VPLMN AMF sends a Nudm SDM Get request to the HPLMN UDM and includes the SoR update indicator or indication of the one or more S-NSSAI(s) of the network slices for SoR information. [00189] Step 3a: the HPLMN UDM considers the indication of SoR for network slices or one or more S-NSSAI(s) for SoR list.

[00190] Step 3b: the HPLMN UDM sends the Nsoraf_SoR_Obtain request with the indication of SoR for network slices or indication of the one or more S-NSSAI(s) of the network slices for SoR list. [00191] Step 3c: the SOR-AF provides updates for a SoR list or one or more SoR list(s) with different associated S-NSSAI(s) in the Nsoraf SoR Obtain response message to HPLMN UDM.

[00192] Step 4: the HPLMN UDM provides a secured SoR list(s) in a Nudm SDM Get response message.

[00193] Step 6: the VPLMN AMF forwards the SoR list(s) to the UE via a Registration Accept message.

[00194] Step 11 : the UE may perform a PLMN selection procedure if a higher priority PLMN is available for the desired network slices of the UE applications.

[00195] Solution 2:

[00196] Following solution 1.1, the subscription information related to network slice includes an indication for allowing VPLMN skipping SD of the subscribed S-NSSAI(s), in which the SD is optional information that complements the Slice/Service type(s) to differentiate amongst multiple Network Slices of the same Slice/Service type.

[00197] If the indication of skipping SD is indicated in a S-NSSAI subscription, the VPLMN can amend its own SD in the S-NSSAI and send to the UE as allowed S-NSSAI.

[00198] Solution 2.1:

[00199] Following solution 2, the SoR list with associated S-NSSAI can contain the indication of skipping SD for a VPLMN. With this indication, the UE is allowed to register with a selected VPLMN in the SoR list associated with a S-NSSAI that has a different SD in the subscribed S-NSSAI of the UE.

[00200] If the indication of skipping SD is indicated in a S-NSSAI subscription, the VPLMN can amend its own SD in the S-NSSAI and send to the UE as allowed S-NSSAI. That is, the UE is allowed to use the allowed S- NSSAI for its service in a PDU session.

[00201] Solution 2.2: [00202] Following solution 1.5, the UE can initiate registration procedure with the additions for the SoR list of "Operator Controlled PLMN Selector with Access Technology and network slices". [00203] Solution 3: solution for use case A

[00204] This solution is to resolve the issues for the use case A and fulfil the following service requirements. This solution is for a UE that uses the same RAT in the first and second PLMN.

[00205] When a roaming UE is to use a network slice not offered by the serving network but available in the area from another network, the HPLMN shall be able to steer the UE to the other network and back to the previous network when the network slice is no longer in use.

[00206] When a roaming UE is to use a network slice not offered by the serving network but available in the area from another network, the HPLMN shall be able to steer the UE to the other network and initiate higher priority PLMN selection based on the type of network slice for ongoing or resuming application when the network slice is no longer in use.

[00207] Solution 3.1: [00208] Following solution 3, when a UE determines to initiate a registration procedure to a selected PLMN in the SoR list with a desired S- NSSAI that cannot be provided by the current first PLMN for the UE application, the UE sends a retention indicator in a NAS message before the UE leaves to a second PLMN. In a NAS response message, the AMF provides a retention timer for the UE registration and initiates the retention timer. During the active retention timer, the network keeps the UE context of the UE.

[00209] If the UE does not return to the AMF, the AMF performs the implicit registration for the UE. [00210] Solution 3.2:

[00211] Following solution 3.1 , the retention indicator is a retention timer. The AMF may modify the retention timer based on the network policy and return the allowed retention timer to the UE. [00212] Solution 3.3:

[00213] Following solution 3.1 or 3.2, the UE starts the retention timer and keeps the UE context for this PLMN when the UE receives the response message.

[00214] Solution 3.4:

[00215] Following solution 3.3, when the UE completes service in the second PLMN before the retention timer is expired, the UE can determine whether to return to the first PLMN while the retention timer is running, based on the UE active applications and the network slices that can be provided by the first PLMN.

[00216] If the UE uses an application that uses a network slice that can be provided by the first PLMN, the UE performs the registration procedure to the first PLMN with mobility registration update. The network stops the retention timer and resumes the services for the UE.

[00217] If the UE uses an application that uses a network slice that cannot be provided by the first PLMN, the UE can initiate a priority PLMN selection procedure based on the SoR list with network slices information. [00218] Solution 4: solution for use case B

[00219] This solution is to resolve the issues for the use case B and fulfil the corresponding service requirements. The solution allows a UE using different RATs to register with the first and second PLMNs for their different network slices simultaneously. [00220] The 5G system shall enable a roaming UE with a single PLMN subscription to access network slices from two VPLMNs simultaneously, when the UE is to use simultaneous access to two network slices and the network slices are not available in a single network.

[00221] The HPLMN shall be able to authorize a roaming UE with a single PLMN subscription to access network slices from two VPLMNs simultaneously.

[00222] The HPLMN shall be able to provide a UE with permission and prioritization information of the VPLMNs the UE is authorized to use for accessing specific network slices. [00223] The 5G system shall enable a UE with a single PLMN subscription to access network slices from HPLMN and another VPLMN simultaneously, when the UE is to use simultaneous access to two networks and the network slices are not available in a single network. [00224] The 5G system shall support a mechanism for the HPLMN to control the timing when a UE with a single PLMN subscription registered on HPLMN or VPLMN, in automatic mode (see clause 3.1 of TS 23.122) and currently in CONNECTED mode, and initiate higher priority PLMN selection for another VPLMN to access network slices from two PLMNs simultaneously based on the type of network slices for ongoing applications.

[00225] Solution 4.1:

[00226] Following solution 4, the UE stores an SoR list that contains "Operator Controlled PLMN Selector with Access Technology and network slices" list. The SoR list can have two options: 1) one SoR list contains VPLMN information with Access Technologies and supported S-NSSAI(s) combination, 2) multiple SoR lists in which each SOR list contains VPLMN information with Access Technologies and associated S-NSSAI.

[00227] When a UE determines to initiate a registration procedure to a selected PLMN associated to a second RAT and its desired S-NSSAI in the SoR list, in which 1) the desired S-NSSAI cannot be provided by the current first PLMN using a first RAT for its application, and 2) the allowed RAT(s) is different from the first RAT, the UE can initiate a registration procedure to the second PLMN using a second RAT that is different from the first RAT for its first registration with the first PLMN.

[00228] For example, the UE can register the first PLMN using 3GPP access that provided the desired first S-NSSAI for application A and B and register the second PLMN using non-3GPP access that provided the desired second S-NSSAI for application C. [00229] This solution can follow the principles at clause 4.7.2.1 in 3GPP

TS 23.501:

[00230] The mobility management procedures defined over 3GPP access are re-used over non-3GPP access with the following exceptions: [00231] a) the registration status, and the 5GMM parameters of the UE's 3GPP access and non-3GPP access 5GMM state machine instances are independent in each of these accesses and can be different;

[00232] b) single-registration mode and dual-registration mode do not apply for 5GMM over non-3GPP access;

[00233] c) the registered PLMN (RPLMN) over non-3GPP access can be different from the RPLMN over 3GPP access. The Mobile Countiy Code (MCC) of the RPLMN over 3GPP access and the MCC of the RPLMN over the non-3GPP access can also be different; [00234] d) the 5GMM over non-3GPP access in the UE considers that the

N1 NAS signalling connection is established when the lower layers indicate that the access stratum connection is established successfully;

[00235] e) the UE-initiated service request procedure via non-3GPP access is supported. Upon indication from the lower layers of non-3GPP access that the access stratum connection is established between the UE and the network, the UE in the 5 GMM -REGISTERED state and in the 5GMM-IDLE mode over non-3GPP access shall initiate the service request procedure via non- 3GPP access. The UE may indicate with the service request message the PDU session(s) associated with non-3GPP access to re-establish user-plane resources for which the UE has pending user data to be sent.

[00236] Although an embodiment has been described with reference to specific example embodiments, it will be evident that various modifications and changes may be made to these embodiments without departing from the broader scope of the present disclosure. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense. The accompanying drawings that form a part hereof show, by way of illustration, and not of limitation, specific embodiments in which the subject matter may be practiced. The embodiments illustrated are described in sufficient detail to enable those skilled in the art to practice the teachings disclosed herein. Other embodiments may be utilized and derived therefrom, such that structural and logical substitutions and changes may be made without departing from the scope of this disclosure. This Detailed Description, therefore, is not to be taken in a limiting sense, and the scope of various embodiments is defined only by the appended claims, along with the full range of equivalents to which such claims are entitled.

[00237] The subject matter may be referred to herein, individually and/or collectively, by the term “embodiment” merely for convenience and without intending to voluntarily limit the scope of this application to any single inventive concept if more than one is in fact disclosed. Thus, although specific embodiments have been illustrated and described herein, it should be appreciated that any arrangement calculated to achieve the same purpose may be substituted for the specific embodiments shown. This disclosure is intended to cover any and all adaptations or variations of various embodiments. Combinations of the above embodiments, and other embodiments not specifically described herein, will be apparent to those of skill in the art upon reviewing the above description. [00238] In this document, the terms "a" or "an" are used, as is common in patent documents, to include one or more than one, independent of any other instances or usages of "at least one" or "one or more." In this document, the term "or" is used to refer to a nonexclusive or, such that "A or B" includes "A but not B," "B but not A," and "A and B," unless otherwise indicated. In this document, the terms "including" and "in which" are used as the plain-English equivalents of the respective terms "comprising" and "wherein." Also, in the following claims, the terms "including" and "comprising" are open-ended, that is, a system, UE, article, composition, formulation, or process that includes elements in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim. Moreover, in the following claims, the terms "first," "second," and "third," etc. are used merely as labels, and are not intended to impose numerical requirements on their objects.

[00239] The Abstract of the Disclosure is provided to comply with 37 C.F.R. §1.72(b), requiring an abstract that will allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, it can be seen that various features are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment.

Claims

CLAIMS What is claimed is:

1. An apparatus for a user equipment (UE), the apparatus comprising: processing circuitry configured to: decode, from a 5^th generation NodeB (gNB), system information, the system information comprising a system information broadcast (SIB) that contains network slice-related information or SIB information related to a slice/service type (SST) to access multiple isolated network slices provided by a public land mobile network (PLMN); access at least one of the network slices from information provided by the PLMN during registration; determine that another of the network slices is to be accessed based on at least one of an active application on the UE or user preference; and in response to a determination to access the other of the network slices, perform cell re-selection using the system information; and a memory configured to store the system information.

2. The apparatus of claim 1, wherein: the system information is provided in a frequencyBandList information element (IE) with corresponding SST type in an intraFreqCellReselectionlnfo IE in SIB2, and the frequencyBandList IE with corresponding SST type of value X, as frequencyBandList_SSTX, indicates a list of frequency bands that support a network slice with the corresponding SST type of value X for which cell reselection parameters apply, and SIB2 contains cell re-selection information common for at least one of intra-frequency, inter-frequency, or inter-radio access technology (RAT) cell re-selection.

3. The apparatus of claim 1, wherein: the system information is provided in an intraFreqNeighCellList information element (IE) with corresponding SST type in SIB3, and the intraFreqNeighCellList IE with corresponding SST type of value X, as intraFreqNeighCellList_SSTX, indicates a list of intra-frequency neighboring cells that support a network slice with the corresponding SST type with specific cell re-selection parameters.

4. The apparatus of claim 1, wherein: the system information is provided in a frequencyBandList information element (IE) with corresponding SST type in an interFreqCarrierFreqList IE in SIB4, the frequencyBandList IE with corresponding SST type of value X, as interFreqCarrierFreqList_SSTX IE, indicates a list of frequency bands that support a network slice with the corresponding SST type of X value for which cell reselection parameters apply, and an interFreqNeighCellList IE with corresponding SST type of value X, as interFreqNeighCellList_SSTX IE, indicates a list of inter-frequency neighboring cells that support a network slice with the corresponding SST type of value X with specific cell re-selection parameters.

5. The apparatus of claim 1 , wherein: the system information is provided in an eutra-multiBandlnfoList information element (IE) with corresponding SST type in a CarrierFreqEUTRA IE in SIB5, the eutra-multiBandlnfoList IE with corresponding SST type, as eutra- multiBandlnfoList_SSTX, indicates a list of E-UTRA frequency bands that support a network slice with the corresponding SST type of value X for which E-

UTRA cell reselection parameters apply, and an eutra-FreqNeighCellList IE with corresponding SST type, as eutra- FreqNeighCellList_SSTX, indicates a list of E-UTRA frequencies of neighboring cells that support a network slice with the corresponding SST type of value X with specific E-UTRA cell re-selection parameters.

6. The apparatus of claim 1, wherein: the UE is in an RRC_CONNECTED mode, the processing circuitry is further configured to encode, for transmission to the gNB, an on Demand SIB request for at least one of SIB2, SIB3, SIB4, or SIB5 with one or more SSTs, and in response to transmission of the on Demand SIB request, the system information is received in a dedicated response or in a broadcast response.

7. The apparatus of claim 6, wherein: the on Demand SIB request comprises a requestedSIB-List information element (IE) and requestedSST-List IE in an onDemandSIB-RequestList IE of a DedicatedSIBRequest IE, and the requestedSIB-List IE and requestedSST-List IE respectively indicate each SIB and SST requested.

8. The apparatus of claim 6, wherein the processing circuitry is configured to: decode, from the gNB in response to the on Demand SIB request containing multiple SSTs, a dedicatedSystemlnformationDelivery information element (IE) of an RRCReconfiguration message, the dedicatedSystemlnformationDelivery IE comprising a frequencyBandList IE for each SST, and determine which frequency band list among the frequencyBandList IE for each SST to use for cell re-selection.

9. The apparatus of claim 1, wherein: the UE is in an RRC_ IN ACTIVE mode, SIB1 includes a si-Schedulinglnfo information element (IE) containing a Schedulinglnfo IE, the Schedulinglnfo IE comprises a SIB-Mappinglnfo that contains a SIB-

Mapping IE, the SIB-Mapping IE comprises a SIB-Typelnfo IE, and the SIB-Typelnfo IE comprises a sibType IE that indicates a SIB type and sstOption IE that indicates an SST for the SIB type.

10. The apparatus of claim 9, wherein: the si-Schedulinglnfo IE contains a si-RequestConfig IE that indicates a configuration of Msg1 resources for UE use to request Si-messages for which a si-BroadcastStatus IE is set to notBroadcasting, and the si-RequestConfig IE contains a si-RequestResources IE that indicates for request resources for a system information (SI) message in which, a sole entry in a list of the request resources is used for all SI messages for which si- BroadcastStatus is set to notBroadcasting and otherwise each increasing entry in the list of the request resources corresponds to an increasing SI message.

11. An apparatus for a user equipment (UE), the apparatus comprising: processing circuitry configured to: decode, during registration with a public land mobile network (PLMN), Steering of Roaming (SoR) information containing a SoR list that is provided by a home PLMN (HPLMN) and includes combinations ofPLMNs and access technology associated with each PLMN; determine, while roaming, that a network slice to be used is offered by a network other than a serving network; and initiate, based on the SoR information, higher priority PLMN selection based on a type of the network slice to be used; and a memory configured to store the SoR information.

12. The apparatus of claim 11, wherein: the UE has a single PLMN subscription, and the processing circuitry is configured to: determine that network slices to be used are not available in a single network, and in response to a determination that the network slices to be used are not available in the single network, as enabled by the HPLMN simultaneously to access network slices from multiple PLMNs including the HPLMN and a visiting PLMN (VPLMN).

13. The apparatus of claim 11, wherein: the UE has a single PLMN subscription, the UE is registered with the HPLMN or a visiting PLMN (VPLMN), the UE is in automatic mode is in RRC_CONNECTED mode, and the processing circuitry is configured to: determine that network slices to be used are not available in a single network, and initiate higher priority PLMN selection for another VPLMN to simultaneously access the network slices from multiple PLMNs based on a type of network slices for ongoing applications.

14. The apparatus of claim 11, wherein: in the SoR list, each PLMN is provided with one or more Single- Network Slice Selection Assistance Information (S-NSSAI) based on subscription information of the UE related to a subscribed S-NSSAI during registration of the UE, and the S-NSSAI identifies a Network Slice and has a Slice/Service type (SST), which refers to expected Network Slice behavior in terms of features and services, and a Slice Differentiator (SD), which differentiates amongst multiple Network Slices of a single SST.

15. The apparatus of claim 14, wherein: each S-NSSAI in the SoR list includes an indication of whether the SD is to be skipped, and the processing circuitry is configured to: determine that the indication for a particular S-NSSAI is set as active, and in response to a determination that the indication for the particular S-NSSAI is set as active, select a visiting PLMN (VPLMN) with an SST in the particular S-NSSAI without considering SD information of the particular S-NSSAI.

16. The apparatus of claim 14, wherein the processing circuitry is configured to: determine that a change of network slices is to be performed for S- NSSAIs that are not supported from the serving network with registration of the

UE, in response to a determination that the change of network slices is to be performed, initiate registration using a registration request message with a registration type indicating a mobility registration update, the registration request message provides information to trigger a procedure to update the SoR list, and in response to transmission of the registration request message: if the UE is registered with the HPLMN, receive an update of the SoR list from an access and mobility function (AMF) of the HPLMN, and if the UE is registered with a visiting PLMN (VPLMN), receive an update of the SoR list from an AMF of the VPLMN forward from the HPLMN.

17. The apparatus of claim 11, wherein: a Single-Network Slice Selection Assistance Information (S-NSSA1) identifies a Network Slice and has a Slice/Service type (SST), which refers to expected Network Slice behavior in terms of features and services, and a Slice Differentiator (SD), which differentiates amongst multiple Network Slices of a single SST, the SoR list includes an indication of whether an SD of each S-NSSAI of each visiting PLMN (VPLMN) is to be skipped, and the processing circuitry is configured to register with a selected VPLMN in the SoR list associated with a S-NSSAI independent of the SD.

18. A non-transitory computer-readable storage medium that stores instructions for execution by one or more processors of a user equipment (UE), the one or more processors to configure the UE to, when the instructions are executed: decode, during registration with a public land mobile network (PLMN), Steering of Roaming (SoR) information containing a SoR list that is provided by a Home PLMN (HPLMN) and includes combinations of visiting PLMNs

(VPLMNs) and access technology associated with each VPLMN; determine, while roaming, that a network slice to be used is offered by an alternate VPLMN other than a serving VPLMN; and in response to the UE being able to unable to simultaneously register with the serving VPLMN and the alternate VPLMN, decode, from the HPLMN, steering information to the alternate VPLMN and when the network slice is no longer in use: decode, from the HPLMN, other steering information to back to the serving VPLMN, or initiate higher priority PLMN selection based on a type of network slice for an ongoing or resuming application.

19. The medium of claim 18, wherein the instructions when executed further configure the one or more processors to configure the UE to: encode, for transmission to the serving VPLMN prior to being steered to the alternate VPLMN, a retention indicator in a non-access stratum (NAS) message, decode, from the serving VPLMN prior to being steered to the alternate VPLMN, a NAS response message containing a retention timer for registration during which at least one of the serving VPLMN or the UE retains a UE context of the UE, and in response to completion of a service in the alternate VPLMN before expiration of the retention timer: determine whether to return to the serving VPLMN based on active applications and network slices that can be provided by the serving PLMN, in response to a determination that the serving VPLMN is able to provide network slices for the active applications, register with the serving VPLMN using a mobility registration update for the serving VPLMN to stop the retention timer and resume services for the UE, and in response to a determination that the serving VPLMN is unable to provide the network slices for the active applications, initiate priority PLMN selection procedure based on SoR list with network slices information, and after expiration of the retention timer, accept implicit registration with the serving VPLMN.

20. The medium of claim 18, wherein the instructions when executed further configure the one or more processors to configure the UE to, in response to the UE being able to able to simultaneously register with multiple PLMNs, decode from the HPLMN: authorization to use a single PLMN subscription to enable simultaneous access by the UE to network slices from the serving VPLMN and the alternate VPLMN or from the serving VPLMN and the HPLMN, permission and prioritization information of the serving VPLMN and the alternate VPLMN for access to specific network slices, and timing information indicating for the UE, when in automatic mode and RRC_CONNECTED mode, to initiate higher priority PLMN selection for simultaneous access to the multiple PLMNs based on a type of network slices for ongoing applications.