KR20170119296A - Method and apparatus for communicating based on network slicing - Google Patents

Abstract

A communication method and apparatus using network slicing are disclosed. A communication method of a communication device for communicating with an initiated user terminal comprises receiving a predetermined request from a user terminal and sending a request to a user terminal of a plurality of network slice instances (NSIs) And selects any one of a plurality of network function instances (NFIs) included in the selected network slice instance to be allocated to the user terminal. Here, the network slice instance is an instantiated form of a network slice that contains one or more network functions and resources for providing a network service with certain performance and characteristics to a user terminal.

Description

TECHNICAL FIELD [0001] The present invention relates to a communication method and apparatus using network slicing,

The following description relates to a communication method and apparatus using network slicing, and more particularly, to a communication method and apparatus for performing network slice instance selection and network function instance selection for providing a network service to a UE.

5G network technology is a 5th generation mobile communication technology that is redesigned into an end-to-end convergence network structure to support various devices and various services as a succeeding technology of 4th generation LTE mobile communication technology. 5G network technology is an end-to-end (E2E) system in which all objects of a network (eg, technology, domain, layer, equipment / Is expected to be.

The present invention can provide the requested network service to the UE through network slicing by selecting a network slice instance and a network function instance corresponding to the requested network service from the UE.

The present invention can provide the flexibility of the 5G core network structure according to the introduction of the network virtualization technology and can allow the network operator to expect the efficiency and the cost reduction according to the network system and the resource management.

A communication method of a communication device for performing communication with a user terminal according to an exemplary embodiment includes receiving a predetermined request from the user terminal; Selecting any one of a plurality of network slice instances (NSIs) in the communication device to be allocated to the user terminal based on the predetermined request; And selecting any one of a plurality of network function instances (NFIs) included in the selected network slice instance to be assigned to the user terminal, wherein the network slice instance has a certain performance And an instantiated form of a network slice that includes one or more network functions and resources to provide network services having characteristics.

In the communication method according to an exemplary embodiment, the step of selecting the network slice instance may select a network slice instance to be allocated to the user terminal based on a Network Slice Selection Assistance Information (NSSAI) included in the predetermined request.

In the communication method according to an exemplary embodiment, the NSSAI may include (a) Slice / Service Type (SST) requested by the user terminal, (b) Slice / Slice Differentiator).

In the communication method according to an exemplary embodiment, the slice / service type may indicate a network operation expected in a service requested by the user terminal.

In the communication method according to an exemplary embodiment, the SD is configured such that when a plurality of network slice instances satisfying the slice / service type is selected, one of the plurality of network slice instances satisfying the slice / Service type can be complemented.

In the communication method according to an exemplary embodiment, the SD may include at least one of a registration area where the user terminal is located, subscription data of the user terminal, QoS attributes of the plurality of network slice instances, .

In the communication method according to an exemplary embodiment, the step of selecting the network slice instance may further include using at least one of the network slice instance allocated to the user terminal and the serving registration area of the user terminal, You can select an instance.

In the communication method according to an exemplary embodiment, the step of selecting the network function instance may include selecting a network function instance based on a logical network identifier representing the selected network slice instance and a type of network function indicating a role performed by the network function instance And select a network function instance to be allocated to the user terminal.

In the communication method according to an embodiment, the step of selecting the network function instance may select one network function instance for each type of network function among the plurality of network function instances included in the selected network slice instance.

In the communication method according to an embodiment, the step of selecting the network function instance may further include a network operator's policy of providing the network slice instance to select a network function instance to be allocated to the user terminal have.

In a communication method according to an exemplary embodiment, the step of selecting the network function instance may include a step of providing a source network function instance (SRF) requesting a selection for the network function instance, the serving network function repository function (NRF) corresponding to the selected network slice instance The network function instance can be selected based on a selection condition received from an S-NFI (Source-Network Function Instance).

In the communication method according to an embodiment, the step of selecting the network function instance includes receiving a network function instance list (NFI list) selectable from a serving network function repository function (NRF) corresponding to the selected network slice instance, A network function instance may select the network function instance and forward information about the selected network function instance to the serving NRF.

A communication method of a communication device for performing communication with a user terminal according to an exemplary embodiment includes receiving a predetermined request from the user terminal; Selecting any one of a plurality of network slice instances (NSIs) in the communication device to be allocated to the user terminal based on the predetermined request; And forwarding a response to a predetermined request in response to the selection of the network slice instance to the user terminal, wherein the network slice instance includes a first one for providing a network service with a certain performance and characteristics to the user terminal, It is an instantiated form of a network slice that contains the above network functions and resources.

In the communication method according to an exemplary embodiment, the step of selecting the network slice instance may select a network slice instance to be allocated to the user terminal based on the NSSAI included in the predetermined request.

The communication method according to an exemplary embodiment of the present invention relocates the current AMF to a new AMF when a new AMF (a new AMF) more suitable than the current AMF is detected to provide the selected network slice instance to the user terminal The method comprising the steps of:

In the communication method according to an exemplary embodiment, when a plurality of network slice instances are allocated to the user terminal, an Access and Mobility Management Function (AMF) and a Network Slice Selection Function (AMF) included in the communication device are allocated to the user terminal Lt; RTI ID = 0.0 > network slice < / RTI >

A communication device according to an embodiment includes a processor; And a memory including at least one instruction executable by the processor, wherein, if the at least one instruction is executed in the processor, the processor receives a predetermined request from a user terminal and, based on the predetermined request, Selects any one of a plurality of network slice instances in the communication device to be allocated to the user terminal, selects one of a plurality of network function instances included in the selected network slice instance to be allocated to the user terminal , The network slice instance is an instantiated form of a network slice that includes one or more network functions and resources for providing network services having certain performance and characteristics to the user terminal.

In a communication device according to an embodiment, the processor may select a network slice instance to assign to the user terminal based on the NSSAI included in the predetermined request.

In a communication apparatus according to an exemplary embodiment, the processor may further use at least one of a network slice instance allocated to the user terminal and a serving registration region of the user terminal to select a network slice instance to be allocated to the user terminal.

A communication device according to an embodiment includes a processor; And a memory including at least one instruction executable by the processor, wherein, if the at least one instruction is executed in the processor, the processor receives a predetermined request from a user terminal and, based on the predetermined request, Selecting one of a plurality of network slice instances in the communication device to be allocated to the user terminal, delivering a response to a predetermined request corresponding to the selection of the network slice instance to the user terminal, An instance is an instantiated form of a network slice that includes one or more network functions and resources for providing network services having certain performance and characteristics to the user terminal.

According to one embodiment, by selecting a network slice instance and a network function instance corresponding to the requested network service from the UE, network slicing can provide the requested network service to the UE.

According to one embodiment, the flexibility of the 5G core network structure according to the introduction of the network virtualization technology can be provided, and the network company can expect the efficiency maximization and the cost reduction effect according to the network system and the resource management.

Figure 1 is a diagram illustrating a reference architecture for network slicing according to one embodiment.
2 is a diagram illustrating a structure of a network slice according to an exemplary embodiment.
3 is an illustration of an example of a network slice instance and a service instance in accordance with one embodiment.
Figure 4 is an illustration of an example of configuring a service instance according to one embodiment.
5 is a diagram illustrating an example of selecting an NSI in a UE registration procedure according to an embodiment.
6 is a diagram illustrating an example of selecting NSI and NFI in the PDU session establishment procedure according to an embodiment.
Figure 7 is an illustration of an example repository in accordance with one embodiment.
8-10 are diagrams illustrating NSI selection and NFI selection in a network slicing architecture in accordance with one embodiment.
11 is a diagram illustrating a communication apparatus according to an embodiment.
12 and 13 are diagrams illustrating a communication method according to an embodiment.
14 is a diagram illustrating an NF discovery service according to an exemplary embodiment of the present invention.
15 is a diagram illustrating an NF discovery service through PLMSs according to an embodiment.

Specific structural or functional descriptions of embodiments are set forth for illustration purposes only and may be embodied with various changes and modifications. Accordingly, the embodiments are not intended to be limited to the particular forms disclosed, and the scope of the disclosure includes changes, equivalents, or alternatives included in the technical idea.

The terms first or second, etc. may be used to describe various elements, but such terms should be interpreted solely for the purpose of distinguishing one element from another. For example, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

It is to be understood that when an element is referred to as being "connected" to another element, it may be directly connected or connected to the other element, although other elements may be present in between.

The singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms "comprises ", or" having ", and the like, are used to specify one or more of the described features, numbers, steps, operations, elements, But do not preclude the presence or addition of steps, operations, elements, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the meaning of the context in the relevant art and, unless explicitly defined herein, are to be interpreted as ideal or overly formal Do not.

The embodiments described below may be used to perform communications. Hereinafter, the operation of performing communication includes selecting at least one of a plurality of network slice instances (NSIs) in a network, selecting one of a plurality of network function instances (NFIs) in a selected network slice instance And selecting at least one. Embodiments may be implemented in various forms of computing devices and / or systems, such as a smart phone, a smart home appliance, a personal computer, a laptop computer, a tablet computer, a wearable device, etc., have. Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Like reference symbols in the drawings denote like elements.

Figure 1 is a diagram illustrating a reference architecture for network slicing according to one embodiment.

Referring to Figure 1, a core part 100 of a network slice in a reference architecture according to one embodiment is shown.

In the case of network slicing, the control plane of the core part 100 of the network slice may be composed of two parts (e.g., a common control part and a slice specific part). Network functions in a common control part (NF) are shared by multiple slice instances, while network functions within a slice-specific part can be dedicate to a particular target slice instance.

In FIG. 1 according to an embodiment, a network slicing non-roaming service-based architecture may be illustrated. Due to network slicing, a Network Slice Selection Function (NSSF) 110, corresponding to additional network functionality, is added to the architecture associated with network slicing deployment to support network slice selection . A more detailed description of the function of the NSSF 110 will be given later.

A control plane network function with darker shadows may be candidates reside in a common control part or slice specific part. Control plane network functions without darker shadows can only be included in a common control part. The darker shadow control plane The ability to include network functionality in a common control part or in a specific part, depending on the target network services supported in the network slice instance, may be subject to the decision of the operator.

Here, the network function may be implemented as a network element on dedicated hardware or as a software instance running on dedicated hardware, or as a virtualised function instantiated on a suitable platform (e.g., a cloud infrastructure) have.

The Access and Mobility Management Function (AMF) 120 may include the following functions. Some or all of AMF 120 functionality may be supported in a single instance of AMF 120.

- Termination of RAN CP interface (N2)

- Termination of the NAS (N1), NAS encryption and integrity protection (Termination of NAS (N1), NAS ciphering and integrity protection)

- Registration management

- Connection management

- Reachability management.

- Mobility Management

- Lawful interception (AMF 120 event and interface with LI system) (Lawful intercept for AMF events and interface to LI System)

- Transparent proxy for routing SM messages for SM message routing.

- Access Authentication

- Access Authorization

- Security Anchor Function (SEA). The SEA may interact with the AUSF and the UE and receive the intermediate key set as a result of the UE authentication process. In the case of USIM-based authentication, the AMF 120 may retrieve security data from the AUSF.

- Security Context Management (SCM). The SCM can receive the key from the SEA used to derive the access network unique key.

Here, there is only one instance of the NAS interface per RAN between the UE and the CN regardless of the number of network functions, and at least one of the network functions that implements NAS security and mobility management is terminated.

When network slicing is deployed, the AMF 120 interacts with the NSSF 110 via the NS interface, so that a network slice instance can be selected. A more detailed description of the selection of the network slice instance will be given later.

Here, the network slicing technology refers to a technology that enables network isolation and customization attributes to be applied to a mobile communication core network structure by bundling network resources and network functions into one independent slice according to services can do. The network slicing technology is a new concept of the 5G core network that has not been used in the existing mobile communication network technology. It is a technology that bundles the network resources and the network functions necessary for the service requested by the mobile terminal into one independent slice.

This allows network operators to independently allocate network resources that are specific to each service and user, and by securing the flexibility of the network through resource virtualization based on Software Defined Networking (SDN) / Network Function Virtualization (NFV) And the scalability and reliability of network resource management can be ensured.

This network slicing technique will be described later with reference to FIG.

2 is a diagram illustrating a structure of a network slice according to an exemplary embodiment.

Referring to FIG. 2, network slice instances assigned to a UE according to one embodiment are shown.

The network slice may be a complete logical network consisting of a set of network functions and corresponding resources required to provide specific network performance and network characteristics. The network slice may reside on a RAN (Radio Access Network) 220 and a CN (Core Network) 230. A network slice instance may be an instantiation of a network slice, i. E., A deployed set of network functions that delivers an intended network slice service (intended Network Slice Services) according to a network slice template.

The AN may be common to multiple network slices. For example, the AN may be a Non-3GPP access network or a 5G RAN.

The network slice can be configured differently depending on the supported functions and network function optimization. Operators can deliver exactly the same optimization and characteristics, but multiple NSIs can be deployed that are dedicate to different groups depending on the nature of the UE.

In FIG. 2, which is illustratively shown, UE 210 may be assigned a plurality of network slice instances 240, 250. Network slice instances 240 and 250 may be defined on RAN 220 and CN 230. For example, the network slice instance 240 may comprise a RAN part 241 and a CN part 243. The CN part 243 can be classified into a Common Control Network Function (CCNF), a Slice-Specific Control Network Function (SCNF), User Plane Functions (UPFs), and others.

Each network slice instance may include one or more network function instances for providing network services required for that network slice instance. For example, the network slice instance 240 may be for multimedia services, and the network slice instance 250 may be for Internet of Things (IoT) services.

UE 210 may access multiple network slice instances 240 and 250 simultaneously through a single RAN 220. [ In this case, the network slice instances 240, 250 may share some control plane functionality (e.g., AMF 260 and NSSF 270). Thus, a control plane function shared by a plurality of network slice instances 240 and 250 assigned to the same UE 210 can be referred to as CCNF.

For example, the UE 210 may use only one AMF 260. In other words, one UE 210 can not use more than one AMF. Conversely, one AMF 260 may be assigned to one or more UEs. FIG. 2 exemplarily shows a case where one AMF is allocated to one UE.

The AMF 260 and the NSSF 270 included in the CCNF may be NF shared among a plurality of network slice instances 240 and 250. In addition, the AUF and PCF may be NF shared among one or more network slice instances according to an operator's policy.

The NSSF 270 is a function included in the CCNF, like the AMF 260, and is used to select a network slice instance corresponding to the UE.

The NSSF 270 may provide a network function with knowledge and an overview of the NSI topology for a given Public Land Mobile Network (PLMN) (e.g., a set of active NSIs (E.g., AMF (260)) that recognizes availability and has access to a particular NSI (ie, the AMF 260) AMF) that is accessible to the specific NSI). The NSSF 270 may also receive the target NSI based on at least one of a Serving Mobile Virtual Network Operator (MVNO), a service or OTT provider (OTT), a location of the UE, or a time window. Level service mapping for a given Single-Network Slice Selection Assistance Information (S-NSSAI). Here, the network slice instance may be selected from a pool of network slice instances for a particular S-NSSAI for load balancing and redundancy.

NSSF 270 may allow the operator to configure slice-level control rules. For example, to provide mission-critical services such as autonomous navigation or remote industrial robot control, a network slice instance with guaranteed low-latency access should be acquired.

NSSF 270 may support statistic collection for slice selection for the management system of the serving PLMN.

Based on the understanding of the NSSF 270 described above, the following parameters may be considered when communicating with the AMF 260.

The input parameters of the NSSF 270 may include an accepted S-NSSAI (Accepted S-NSSAI). In addition, in some cases, at least one of the past associated NSI list of UE 210 and the serving registration area of UE 210 may be further considered as an input parameter of NSSF 270.

The output parameter of the NSSF 270 may include information (e.g., an NSI ID) for the newly selected serving network slice instance corresponding to the accepted S-NSSAI. Additionally, in some cases, at least one of the IP address or Fully Qualified Domain Name (FQDN) of the selected new serving AMF and the IP address or FQDN of the Selected Serving NRF (NF Repository Function) for the selected NSI is stored in the NSSF 270). ≪ / RTI >

For a network share, each PLMN may include a self-provisioned NSI and corresponding NRF for NF discovery and selection within the network slice instance. In addition to the type of network function, a "logical network identifier" is provided as an input parameter to the NRF for NF discovery and selection so that the NRF can support network function discovery and selection operations with or without network slicing . In the case of network slicing, the logical network identifier represents the NSI ID, and in other cases the logical network identifier may represent the serving PLMN.

3 is an illustration of an example of a network slice instance and a service instance in accordance with one embodiment.

Referring to FIG. 3, a network slice instance 310 and a service instance 320 are illustrated in accordance with one embodiment.

One or more network slice instances 310 may be defined in the network system. One or more of the one or more network slice instances 310 may be selected to provide the service required by the UE. The concrete operation concerning the selection of the network slice instance will be described later.

The network slice instance 310 may be a set of network function instances prepared to support the network service required by the UE. One or more network function instances may provide the same network functionality (e.g., SMF (Session Management Function)) within the network slice instance 310. If there are a plurality of network function instances providing the same network function in the same network slice instance 310, any one of a plurality of network function instances may be selected. Concrete operations relating to network function instance selection will be described later.

One network slice instance 310 may be assigned to one or more UEs and may be assigned to one or more services. The network slice instance 310 may correspond to an operator's service resource group.

The service instance 320 may be a collection of serving network function instances supporting the service required by the UE. The service instance 320 may include all the network functions required for the corresponding service. The service instance 320 may refer to a network slice instance allocated to the actual UE.

Figure 4 is an illustration of an example of configuring a service instance according to one embodiment.

Referring to FIG. 4, an example is illustrated to illustrate the process of configuring a service instance 430 through an NSI selection 410 and an NFI selection 420 according to an embodiment.

In the NSI selection 410, any one of a plurality of network slice instances defined in the network system may be selected. At this time, the network slice instance can be selected based on the NSSAI. Additionally, at least one of the previously assigned network slice instance of the UE and the serving registration area of the UE may be further considered and the network slice instance may be selected. As a result of selection, an available NSI ID can be output. Additionally, at least one of the new AMF and the IP address of the serving NRF for the selected NSI may be further output. A more detailed description thereof will be described later.

In the NFI selection 420, any one of a plurality of network function instances in the selected network slice instance may be selected. At this time, the network function instance can be selected based on the logical network identifier and the type of network function. The logical network identifier may represent an NSI ID if network slicing is used and a serving PLMN if network slicing is not used. The type of the network function may be, for example, AMF, NSSF, SMF, UPF, AUF, PCF and the like. One network function instance may be selected for each type of network function required to provide the network service requested by the UE.

In FIG. 4, which is illustratively shown, there may be a plurality of SMFs in a selected network slice instance. A situation may arise where one network function instance can not be selected even though the logical network identifier (i.e., the selected NSI ID) and the type of network function (i.e., SMF) are taken into account. In this case, an operator policy may be additionally considered. An operator policy is a policy set by a network operator and may include, for example, load balancing, resource optimization, energy efficiency, traffic optimization, and the like.

For example, an SMF having a small number of currently used UEs among two SMFs may be selected. Alternatively, one of the two SMFs may be selected with a better quality of service (QoS). Alternatively, the SMF corresponding to the charging plan of the corresponding UE among the two SMFs (for example, the basic charging rate and the premium charging rate) may be selected. Alternatively, the SMF corresponding to the serving registration area of the corresponding UE among the two SMFs may be selected. In some cases, one or more of the various criteria described above may be considered to select a network function instance.

Service instance 430 may refer to a selected network slice instance that includes a selected network function instance. The service instance 430 may refer to a network slice instance that is capable of fully providing the network service requested by the UE.

Hereinafter, NSI selection 410 and NFI selection 420 will be described in more detail. The NSI selection 410 may be performed in the UE registration procedure and the PDU session establishment procedure, and the NFI selection 420 may be performed in the PDU thinning establishment procedure.

If the network supports network slicing, one or more network slice instances may be selected using Network Slice Selection Assistance Information (NSSAI) provided from the UE. NSSAI is a set of S-NSSAIs. Each S-NSSAI may be used to select a particular network slice instance. In addition, UE capabilities and UE subscription data may be used to select a network slice instance.

The S-NSSAI may include Slice / Service type (SST) and Slice Differentiator (SD). Slice / service type indicates expected network behavior in terms of characteristics and services. The SD is optional information that complements the slice / service type and can differentiate a plurality of network slice instances satisfying the SST.

The UE subscription data may include information about the network slice instances to which the UE is allowed to access. The information in the UE subscription data may include an S-NSSAI allowed for use by the UE.

In addition, the UE subscription data may include information about whether the corresponding S-NSSAI is the default S-NSSAI. The default S-NSSAI may indicate a network slice instance that the UE should use when connecting to the network system. In other words, if the UE initially registers with the network system without providing any NSSAI in the registration request, the CN may use the default initial NSI to service the UE, It should use the default NSSAI configured with S-NSSAIs stored in the UE subscription data with a flag indicating that it should be considered. In addition, the UE subscription data may include a default DNN (Data Network Name) value for the S-NSSAI.

The CN part of the network slice instance serving the UE may be selected by the CN rather than the RAN. The UE can simultaneously access multiple network slice instances via a single RAN. In this case, the network slice instances that are simultaneously accessed by the UE may share some control plane functionality including the AMF in the core network.

The AMF selection for the set of network slice instances for the UE may be triggered by the first contacted AMF in the Registration Procedure and may lead to a change in AMF. Once a target network slice instance is selected and a Session Management (SM) message for establishing a PDU session is received from the UE, subsequent SMF network capability discovery and selection may be initiated by the AMF . NRF can be used to perform this selection task.

A PDU session may belong to a particular network slice instance. Other NSIs do not share PDU sessions, but other network slice instances may contain slice-specific PDU sessions for the same DNN.

The S-NSSAI may include standard values or a PLMN-specific value. The S-NSSAIs with PLMN-specific values may be associated with the PLMN IDs of PLMNs that allocate S-NSSAIs at the UE. One S-NSSAI shall not be used by the UE in the access stratum procedures in PLMN other than the PLMN associated with the S-NSSAI (AS-NSSAI shall not be used by the UE in the access stratum procedures in any PLMN other than the one to which the S-NSSAI is associated).

The NSSAI is used to select a set of AMF and network slice instances (a set of NSIs), while the S-NSSAI can be used to select a network slice instance. Each S-NSSAI included in the NSSAI may include (a) slice / service type or (b) slice / service type and SD.

The UE may store Configured and / or Accepted NSSAI (NSSAI) configured and / or approved for each PLMN. The configured NSSAI may be an NSSAI configured by an HPLMN (Home PLMN) in the UE to be used in the PLMN if no PLMN-specific approved NSSAI is stored in the UE.

The approved NSSAI is the NSSAI provided to the UE from the PLMN and the UE shall use the approved NSSAI after the PLMN has successfully registered the UE. A Registration Accept message may include an approved NSSAI. The approved NSSAI may be updated in a subsequent Registration Procedure.

If a configured or accepted NSSAI for the PLMN to which the UE is accessing is provided to the UE then the UE shall establish such an NSSAI in the RRC Connection Establishment (RRC) and Non-access stratum (NAS) . The RAN can route the initial access to the AMF using the provided NSSAI.

If the UE does not receive any approved NSSAI for the PLMN that it is accessing and is provided with a configured NSSAI, the UE may establish an RRC connection and provide the NSSAI configured in the NAS to the RAN. The RAN may use the NSSAI to route the initial access to the AMF. Alternatively, if no approved NSSAI or configured NSSAI is provided for the PLMN that the UE is accessing, the UE does not provide the NSSAI in RRC connection establishment and NAS, and the RAN can send NAS signaling to the default AMF.

A network operator may provide a Network Slice Selection Policy (NSSP) to the UE. An NSSP may include one or more NSSP rules that associate an application with a particular S-NSSAI. The NSSP may also include a default rule that matches all applications and includes a default S-NSSAI. The UE may use the NSSP to associate the UE application with the S-NSSAI.

When a UE application associated with a particular S-NSSAI requires data transmission, and the UE has more than one PDU session established with this particular S-NSSAI, the UE Lt; / RTI > may route the user data of the application in any one of these PDU sessions. If the application provides a DNN, the UE can determine which PDU session to use considering this DNN.

When a UE application associated with a particular S-NSSAI requests a data transfer, if the UE does not have a PDU session established with this particular S-NSSAI, the UE sends a new PDU session. (The UE requests a new PDU session with this S-NSSAI and with the DNN that may be provided by the application).

5 is a diagram illustrating an example of selecting an NSI in a UE registration procedure according to an embodiment.

Referring to Fig. 5, a communication method performed by a user terminal and a communication device is shown. The UE illustrated in FIG. 5 denotes a user terminal, and AMF, NSSF, UDM, and new AMF may denote network function instances included in a communication device.

At step 501, the UE sends a registration request to the AMF. The UE may send a registration request to the AMF along with either the default NSSAI, the configured NSSAI, and the approved NSSAI via the RAN. Here, AMF may be initial AMF.

At step 503, a General Registration procedure may be performed.

In step 505, the AMF may send an Authorization / Subscription Check Request with the NSSAI to the UDM.

In step 507, the UDM can check whether the NSI requested by the NSSAI is usable by the UE.

At step 509, the UDM may send an authentication / subscription check response to the AMF along with the approved NSSAI. That is, the AMF can obtain an authenticated NSSAI from the UDM and thereby determine a potentially accepted S-NSSAI (potential accepted S-NSSAI).

In step 511, the AMF may send an NSI Selection Request to the NSSF along with the approved NSSAI.

At step 513, the NSSF may determine the availability of the NSI requested by the approved NSSAI. If a more appropriate AMF that can provide the NSI selected in the NSSF is detected than the current AMF (i.e., the AMF that sent the NSI selection request to the NSSF), then the NSSF provides information about the new AMF to the current AMF can do.

At step 515, the NSSF may forward the information about the selected NSI to the AMF in an NSI selection response. The NSSF may also pass information about the new AMF to the AMF in an NSI selective response.

If the current AMF has decided to relocate the serving AMF for the UE, then in step 517, the AMF may trigger the AMF relocation procedure using information about the new AMF provided by the NSSF.

At step 519, a generic registration procedure may be performed.

At step 521, the AMF may send a Registration Accept message to the UE along with the approved NSSAI.

That is, in the UE registration procedure, the AMF may obtain an approved NSSAI from the UDM and determine a set of potentially accepted S-NSSAs (S-NSSAIs). And, by verifying the set of potentially approved S-NSSAIs through the NSSF, the availability of the NSI along with the serving registration area of the UE can be determined.

The approved NSSAI may be configured to perform the following functions: (a) an authentication / subscription check performed in consultation with a UDM providing a list of authenticated NSSAIs, (2) a request for registration of the UE based on the availability checking of the NSI performed by negotiating with the NSSF provided by OA & As shown in FIG. In addition, the approved NSSAI may change depending on the result of the NSI availability check in the NSSF as well as the Subscription Check.

Upon initial slice selection or successful Attachment Registration, the UE may be provisioned with a temporary ID in RRC connection establishment of the subsequent initial access so that the RAN can route the NAS message to the appropriate AMF as long as the Temp ID is valid . In addition, the serving PLMN may return an approved NSSAI including the PLMN ID of the serving PLMN. The approved NSSAI may include the S-NSSAI of the network slice instance approved by the PLMN for use by the UE. Here, it is assumed that the RAN and core slicing-related configuration are not changed within the registration area of the UE.

In order to route the NAS signaling with correct CN functions, the UE may include a complete Temp ID (complete Temp ID) in the NSSAI and RRC stored for the PLMN. If the RAN can recognize and reach the AMF associated with the Temp ID, the RAN can forward the request to this AMF. Otherwise, the RAN may select an appropriate AMF (suitable AMF) based on the NSSAI provided by the UE and send the request to the selected AMF. If the RAN can not select an AMF based on the approved NSSAI, the request is sent in the default AMF.

The UE must include the DNN of the data network for the PDU session and the S-NSSAI enabling the selection of the SMF in the PDU session establishment request NAS message.

The RAN needs to recognize the network slice used by the UE so that the RAN can select the proper resources to support network slicing in the RAN.

The UE may change the set of network slice instances in use by the network by submitting a new value of the NSSAI to the Registration Request procedure. The final decision of the set of network slices assigned to the UE may be performed by the network.

The network may be used by the UE by providing the UE with a notification of Accepted NSSAI change of the approved NSSAI change based on local policies, subscription changes and / or UE mobility. You can change the set of NSIs to be. This may trigger a UE initiation registration procedure including an RRC and NAS signaling a new approved NSSAI (New Accepted NSSAI) provided by the network (This is a UE initiated Registration procedure including in RRC and NAS Signaling the value of the new Accepted NSSAI the network has provided).

Alteration of a set of network slice instances initiated by the UE or network may result in an AMF change in accordance with an operator policy. The change in the set of network slice instances that the UE can access is such that if these network slice instances are no longer used (at this time, the other slices may still be available), a PDU in progress with the original set of network slices Termination of the ongoing PDU session may result.

If it is determined by the network that the UE should be serviced by another AMF during the initial registration procedure, the AMF that has received the initial registration request previously receives the initial registration request via the RAN or through the direct signaling between the initial AMF and the target AMF, To be redirected. A redirection message sent by the AMF over the RAN may contain information about the target AMF for servicing the UE.

For UEs already registered, the network system must support retransmission of the UE from the serving AMF to the target AMF. The operator policy can determine whether retransmission between AMFs is allowed.

If the network has decided to retransmit the UE due to a change in NSSAI, then the network will either (a) update / new NSSAI with the UE using a Registration Update Required Procedure and (b) May send an indication to the UE to initiate the registration update procedure with the updated / new NSSAI.

The AMF may select the SMF in the network slice instance based on the S-NSSAI, DNN and other information (e.g., UE subscription and local operator policy). The selected SMF can establish a PDU session based on the S-NSSAI and DNN.

6 is a diagram illustrating an example of selecting NSI and NFI in the PDU session establishment procedure according to an embodiment.

Referring to FIG. 6, a communication method performed by a user terminal and a communication device is shown. The UE shown in FIG. 6 denotes a user terminal, and AMF, NSSF, NRF, and SMF may refer to network function instances included in a communication device.

In step 601, the UE may send a PDU Session Establishment Request with the S-NSSAI approved as AMF over the RAN.

In step 603, the AMF may send an NSI selection request to the NSSF along with the approved S-NSSAI and the active NSI accessed by the UE.

In step 605, the NSSF may select the corresponding NSI according to the serving registration area of the UE.

In step 607, the NSSF may respond to the AMF with a serving NRF corresponding to the selected serving NSI and the selected NSI.

In step 609, the AMF may select the SMF by interacting with the serving NRF corresponding to the selected NSI.

In step 611, UE Request PDU Session Establishment may be performed.

That is, upon establishing a PDU session, the AMF may verify through the NSSF a set of potentially approved S-NSSAIs to determine the availability of the NSI along with the UE's serving registration area. The AMF may also provide the NSSF with active NSI information accessed by the UE. The NSSF may provide the serving NRF information corresponding to the selected serving NSI and the selected NSI to the AMF in response.

Figure 7 is an illustration of an example repository in accordance with one embodiment.

Referring to FIG. 7, an NFI repository 710 and a serving NF repository 720 are shown.

The NRF may manage the NFI repository 710 and the serving NF repository 720. The NFI repository 710 may include information about network function instances in the network system. For example, the NFI repository 710 may include an NFI ID, an NF type, an NSI ID, and a FQDN / IP. The NFI ID is an identifier for the network function instance, and the NSI ID can be an identifier for the network slice instance including the network function instance.

The NFI repository 710 may be updated by Operations, Administration and Management (OAM). Specifically, an NSI orchestration included in the OAM can instantiate a network slice, update and terminate a network slice instance. In addition, the NFI orchestrations included in the OAM can instantiate network functions, update and terminate network function instances, and scale and migrate.

The NFI selection may be performed using the information contained in the NFI repository 710. When an NFI selection occurs, the NRF may store information about the selected NFI in the serving NF repository 720. In other words, the serving NF repository 720 may include information about the serving NFI selected for the UE. The NFI included in the serving NF repository 720 may constitute a service instance.

The NRF can support the service discovery function. When an NF discovery request is received from the network function instance, the NRF may provide information about the discovered network function instance to the NF discovery requested network function instance.

In addition to the network function type, a logical network identifier may be provided to the NRF so that the NRF can support network function selection and discovery operations with or without network slicing. In the case of network slicing, the logical network identifier represents the NSI ID, and in other cases the logical network identifier represents the serving PLMN.

8-10 are diagrams illustrating NSI selection and NFI selection in a network slicing architecture in accordance with one embodiment.

Referring to FIG. 8, a selection of a network slice instance and a network function instance according to an embodiment is shown.

UE 1 810 may access CN network slice instance A 820 selected by the core network via the RAN and NFI selection may access network function instances MM1, SM1, PC1 Can be selected. Similarly for UE 2 and UE 3, the NFI selection can select a network slice instance corresponding to that UE and a network function instance in that network slice instance.

The network slice instance selection procedure for the UE may be performed based on the NSSAI configured for the UE. The UE may report the NSSAI to the network. Based on the NSSAI provided by the UE and other information available in the network (e.g., subscription data), a network slice instance may be selected.

A network slice instance for the UE may be selected depending on the type of application and service required. The selection for such a network slice instance may take into account factors such as UE capability, configuration and authorization.

The selection for the network slice instance and the network function instance can select an appropriate network function instance that can provide a particular service within the selected network slice according to a predetermined selection criterion.

The predetermined selection criterion may mean NSSAI, and NSSAI may include slice / service type (e.g., eMBB service, Critical communications (CriC), massive machine type communication (mMTC)) and SD.

The network may use the NSSAI with other information (e.g., subscription data) available on the network to select the appropriate network slice instance and network function instance. Below is a mechanism for network slice instance and network function instance selection.

Two-step selection mechanism

As a first step, the network slice instance selection function can select an appropriate network slice instance in the core network using NSSAI with information available on the network (e.g., subscription data). Then, in the second step, the network function instance selection function can select an appropriate network function instance in the network slice instance selected in the first step using a resource operation policy or the like.

One-step selection mechanism

The network slice instance selection function selects a network slice instance for the UE and a network function instance for each network function type using slice / service type and SD together with information available on the network (e.g., subscription data) As shown in FIG.

The network function instance selection function may also collect QoS attributes (e.g., delay, throughput) of the network function instance and may use the QoS attribute to select a network function instance for the UE within the network slice instance Can be.

Referring to FIG. 9, there is conceptually illustrated the function of selecting a network slice instance and a network function instance in a core network according to an embodiment.

The UE 1 may forward the NSSAI to the core network 910 via the RAN and the network slice instance selection 911 may be performed based on the NSSAI. Then, the network function instance selection 913 can be performed. Here, the network slice instance selection 911 is performed by the NSSF, and the network function instance selection 913 can be performed by the NRF. Specifically, the NRF can perform NFI selection and NFI discovery.

At this time, the network slice management and orchestration 920 may monitor network function instances (e.g., NFa # 1, NFb # 1, NFc # 1 shown in FIG. 9) included in the network slice instance. The NSSF can perform the network slice instance selection 911 and the network function instance selection 913 in consideration of the monitoring result. For example, a monitoring operation may be performed for the QoS of each network function instance, and may be represented by a dot-dash line in Fig.

When the network function instance selection 913 is performed, an entry update can be performed. The results of the network slice instance selection 911 and the network function instance selection 913 may be stored in the serving NF repository 915.

Within a network slice instance, a network function instance can be selected in consideration of redundancy, scalability, performance, and the like. Therefore, it is necessary to determine a set of network function instances corresponding to each UE service request according to the policy of the network operator. Additionally, load balancing, resource optimization, energy efficiency, etc. may be further considered to select network function instances 913.

The network slice management and orchestration 920 can provide a network operator's resource operation policy, provide QoS attributes of network function instances, and manage the life cycle of network function instances.

10, there is shown an NRF 1010 that performs network function instance selection / discovery functions in accordance with one embodiment.

The NRF 1010 may manage selection results for network function instances and, if requested from the network function instances, perform discovery for selected network function instances.

Within the network slice instance, multiple instances of network functionality may be provided for redundancy, scalability, and the like. That is, different instances of the same network function may have different QoS attributes such as capability, performance, and so on. Depending on the QoS attribute of the network function instance, it may be possible to select an appropriate network function instance within the network slice instance, or to reselect the network function instance so that the specific QoS attribute is satisfied.

The selection of these network function instances can be based on the following principles.

A network slice instance can consist of multiple network function instances for a particular service with network capability. The requested network slice instance per UE service may be selected using 'network slice selection support information' (NSSAI). More than one network function instance may be provided for each of the various network function types for performance, redundancy, scalability, etc. within the network slice instance. A set of network function instances may be selected for each UE service request for binding. The selection of a network function instance may be performed according to the policy of the network operator (e.g., energy efficiency, load balancing, resource optimization, etc.). The binding information of the selected NFI may be further provided to the NRF 1010. At the time of roaming, the set of network function instances can be updated by reselecting the network function instance or by changing the QoS attribute of the network function instance, the network operator's policy, roaming, and the like.

The NSSF may select an appropriate network slice instance based on the NSSAI. Specifically, the NSSF may determine a target network slice instance classified into the service type requested by the UE, and may select a network slice instance based on the various UEs and the network-provided NSSAI. For example, the NSSAI may include UE subscription data, policies of network operators, and the like.

The NRF may select an appropriate network function instance using the network operator's resource operational policies (e.g., load balancing, resource optimization, etc.). Specifically, the NRF identifies the NF (or NF type) of a given network slice, determines any one of multiple instances of each NF (or NF type) within a given NSI, and binds the binding information of the selected NFIs to the NRF 1010 ) ≪ / RTI > in the serving NF repository.

11 is a diagram illustrating a communication apparatus according to an embodiment.

Referring to FIG. 11, a communication device 1100 according to one embodiment includes a memory 1110 and a processor 1120. The memory 1110 and the processor 1120 can communicate with each other via a bus 1130.

Memory 1110 may include instructions readable by a computer. The processor 1120 may perform the aforementioned operations as the instructions stored in the memory 1110 are executed in the processor 1120. [ The memory 1110 may be a volatile memory or a non-volatile memory.

The processor 1120 may execute instructions or programs, or may control the communication device 1100. [ The communication device 1100 may be implemented as part of various computing devices. In addition, the communication device 1100 can process the above-described operations.

Upon UE registration, the processor 1120 receives a registration request from the user terminal, selects a network slice instance to assign to the user terminal of the plurality of network slice instances in the communication device based on the registration request, And transmits a registration approval message to the user terminal. Here, the network slice instance is an instantiated form of a network slice that contains one or more network functions and resources for providing a network service with certain performance and characteristics to a user terminal.

In addition, upon establishing a PDU session, the processor 1120 receives a PDU session establishment request from the user terminal and, based on the PDU session establishment request, sends a request to the user terminal of the plurality of network slice instances (NSIs) Selects a network slice instance to be allocated, and selects a network function instance to be allocated to the user terminal among a plurality of network function instances included in the selected network slice instance. Here, the network slice instance is an instantiated form of a network slice that contains one or more network functions and resources for providing a network service with certain performance and characteristics to a user terminal.

The components described in FIG. 11 through FIG. 1 through FIG. 10 are applied as they are, so that detailed description is omitted.

12 and 13 are diagrams illustrating a communication method according to an embodiment.

Referring to FIG. 12, there is shown a communication method of a communication device that performs communication with a user terminal in UE registration according to an embodiment.

In step 1210, the communication device receives a predetermined request from the user terminal. The predetermined request may include an NSSAI. For example, the predetermined request may be a registration request.

In step 1220, the communication device selects a network slice instance to assign to the user terminal of the plurality of network slice instances in the communication device based on the predetermined request. The communication device may select a network slice instance to assign to the user terminal based on the NSSAI included in the predetermined request.

The NSSAI may include (a) Slice / Service Type (SST) requested by the user terminal or (b) slice / service type and SD (Slice Differentiator) corresponding to the user terminal. The slice / service type may indicate the expected network activity in the service requested by the user terminal. The SD may supplement the slice / service type such that if there are a plurality of network slice instances satisfying the slice / service type, one of a plurality of network slice instances satisfying the slice / service type is selected. The SD may include at least one of a registration area where a user terminal is located, subscription data of a user terminal, QoS attributes of a plurality of network slice instances, and terminal characteristics.

The communication device may further utilize at least one of the network slice instance pre-assigned to the user terminal and the serving registration area of the user terminal to select a network slice instance to assign to the user terminal.

In step 1230, the communication device communicates a response to the predetermined request to the user terminal in response to the network slice instance selection. For example, the response to the predetermined request may be a registration approval message.

The communication device may also perform relocation from the current AMF to the new AMF if a new AMF that is more appropriate than the current AMF is detected to provide the selected network slice instance to the user terminal. The AMF and the NSSF included in the communication device may be shared by a plurality of network slice instances assigned to the user terminal when a plurality of network slice instances are assigned to the user terminal.

Referring to FIG. 13, a communication method of a communication apparatus performing communication with a user terminal in establishing a PDU session according to an embodiment is illustrated.

In step 1310, the communication device receives a PDU session establishment request from the user terminal.

In step 1320, the communication device selects a network slice instance to assign to the user terminal of the plurality of network slice instances in the communication device based on the predetermined request. For example, the predetermined request may be a PDU session establishment request.

The communication device may select a network slice instance to assign to the user terminal based on the NSSAI included in the predetermined request.

The NSSAI may include (a) Slice / Service Type (SST) requested by the user terminal or (b) slice / service type and SD (Slice Differentiator) corresponding to the user terminal. The slice / service type may indicate the expected network activity in the service requested by the user terminal. The SD may supplement the slice / service type such that if there are a plurality of network slice instances satisfying the slice / service type, one of a plurality of network slice instances satisfying the slice / service type is selected. The SD may include at least one of a registration area where a user terminal is located, subscription data of a user terminal, QoS attributes of a plurality of network slice instances, and terminal characteristics.

The communication device may further utilize at least one of the network slice instance pre-assigned to the user terminal and the serving registration area of the user terminal to select a network slice instance to assign to the user terminal.

In step 1330, the communication device selects a network function instance to assign to the user terminal, among the plurality of network function instances included in the selected network slice instance. The communication device may select a network function instance to assign to the user terminal based on a type of network function indicating a logical network identifier representing the selected network slice instance and a role performed by the network function instance. The communication device may select one network function instance for each type of network function among the plurality of network function instances included in the selected network slice instance. The communication device may further select a network function instance to assign to the user terminal, taking into account the policy of the network operator providing the network slice instance.

In addition, the communication device may select a network function instance based on a selection condition received from a source-network function instance for which a serving NRF corresponding to the selected network slice instance requests a selection for the network function instance. That is, an NRF-driven NFI selection can be performed.

In addition, the communication device may select a network function instance from the source-network function instance that received the selectable NFI list from the serving NRF corresponding to the selected network slice instance, and forward the information about the selected network function instance to the serving NRF. That is, an NF-driven NFI selection can be performed. More specifically, the source-network function instance may request a list of destination-network function instances (D-NFI) to the NRF. The NRF may return the IP address of the destination-network function instance in the corresponding network slice instance in response to the request. The source-network function instance can select one of the destination-network function instances from the list received from the NRF and manage the status.

A network slice instance is an instantiated form of a network slice that contains one or more network functions and resources for providing network services having certain performance and characteristics to a user terminal.

12 and 13 are applied to the steps described above with reference to FIGS. 1 to 11, the detailed description will be omitted.

The terms that may be used or used herein according to one embodiment are as follows.

5G Access Network: An access network that includes a 5G-RAN and / or a Non-3GPP AN connecting to a 5G core network.

5G Core Network: Core network. 5G access network.

5G QoS Flow: Best granularity for QoS forwarding processing in 5G systems. All traffic mapped to the same 5G QoS flow can receive the same forwarding process (eg, scheduling policy, queue management policy, rate shaping policy, RLC configuration, etc.). A separate 5G QoS flow may be required to provide different QoS forwarding processing.

5G QoS indicator (5QI): Scala used as a reference for specific QoS forwarding behavior (eg packet loss rate, packet delay budget) provided in 5G QoS flows. This may be implemented in the access network by 5QI reference node specific parameters that control QoS forwarding processing (e.g., scheduling weights, tolerance thresholds, queue management thresholds, link layer protocol configuration, etc.).

5G-RAN: Wireless access network supporting one or more of the following options with common characteristics connected to 5GC:

1) Standalone new radio.

2) The new radio can be an anchor with E-UTRA extension.

3) Stand-alone E-UTRA.

4) E-UTRA can be an anchor with New Radio extension.

5G system: 3GPP system consisting of 5G access network (AN), 5G core network and UE.

Allowed NSSAI: eg NSSAI provided by the serving PLMN. A registration procedure indicating the NSSAI allowed by the network for the UE in the serving PLMN for the current registration area.

Permissive Area: The area where the UE can initiate communication.

Established NSSAI: NSSAI provisioned to the UE.

Forbidden area: An area where the UE can not initiate communication.

Initial registration: UE registration in RM-DEREGISTERED state.

Mobility pattern: A network concept that determines UE mobility parameters within the NF.

Mobility Registration Update: UE re-enrollment when entering a new TA outside the TAI list.

Network function: 3GPP can adopt the processing function in the network defining the function operation and the 3GPP definition interface or can define it in 3GPP.

Non-allowed area: An area where the UE can initiate the registration process but no other communication can begin.

PDU Connectivity Service: A service that provides PDU exchange between UE and data network.

PDU session: The association between the UE and the data network providing the PDU connection service. The connection type may be IP, Ethernet or unstructured.

Regular registration update: Re-enroll the UE when the periodic registration timer expires.

Requested NSSAI: The NSSAI that the UE can provide to the network.

Service continuity: An uninterrupted user experience, including when IP addresses and / or fixed points change.

Session Continuity: The continuity of the PDU session. For a PDU session of IP type "session continuity ", this may mean that the IP address is maintained for the lifetime of the PDU session.

Non-seamless Non-3GPP offload: offload of user plane traffic through non-3GPP access without passing through N3IWF or UPF and untrusted.

The network slicing introduced herein in accordance with one embodiment may be as follows.

The network slice may include the following:

- Core network control plane and user plane network function

- 5G wireless access network

- N3IWF can function for non-3GPP access networks.

The network slice may vary depending on the features supported and network function optimization. The operator may provide exactly the same functionality but place the same network slice instance for different groups of UEs. This may be because the customer is able to provide other dedicated services or devote to the customer.

A single UE may be able to be serviced simultaneously by more than one network slice instance via 5G-AN. The AMF instance serving the UE may logically belong to each network slice instance serving the UE. That is, this AMF instance may be common to the network slice instance serving the UE.

A PDU session may belong to one specific network slice instance per PLMN. Other network slice instances may not share PDU sessions, but other slices may have slice-specific PDU sessions that use the same DNN.

Identification and selection of network slices: S-NSSAI and NSSAI

The S-NSSAI (single network slice selection support information) can identify the network slice.

The S-NSSAI can consist of:

- Slice / Service type (SST): It can indicate expected network slice operation in terms of function and service.

Slice Differentiator (SD), which is optional information to supplement the Slice / Service type - allows differentiation in selecting network slice instances from potential multiple network slice instances that comply with all Slice / Service types shown. This information can be called SD.

The S-NSSAI may have a standard value or a PLMN specific value. The S-NSSAI with a PLMN unique value is associated with the PLMN ID of the PLMN to which it is assigned. The S-NSSAI shall not be used by the UE in an access-stratum procedure in a PLMN other than the PLMN to which the S-NSSAI is associated.

The NSSAI may be a collection of S-NSSAI (Single Network Slice Selection Support Information). Each S-NSSAI can support the network when selecting a particular network slice instance. The CN portion of the network slice instance (s) serving the UE is selected by the CN.

(R) AN may use the NSSAI requested in the access layer signaling to process the UE control plane connection before informing the (R) AN of the NSSAI that the 5GC is allowed. The requested NSSAI is not used by the RAN for routing when the UE also provides a temporary user ID.

Once the UE is successfully registered, the CN informs the (R) AN by providing the entire NSSAI allowed for the control plane side.

Once a PDU session is established for a particular slice instance, the CN can provide the R-AN with an S-NSSAI corresponding to the slice instance to which this PDU session belongs so that the RAN can perform the access-specific function.

Subscription aspects

The subscription data may include the S-NSSAI of the network slice to which the UE subscribes. One or more S-NSSAIs may be marked as primary S-NSSAIs. If the S-NSSAI is indicated by default, the UE is expected to serve the UE with the relevant network slice in the registration request even if the UE does not transmit any S-NSSAI to the network.

The UE subscription data may include a default DNN value for a given S-NSSAI.

The NSSAI provided by the UE in the registration request is verified against the subscription data of the user.

UE NSSAI configuration and NSSAI storage aspects

The UE may be configured by the HPLMN with an NSSAI configured per PLMN. . The configured NSSAI may be specific to the PLMN and the HPLMN indicates which PLMN (s) each configured NSSAI applies, including whether the configured NSSAI is applied to all PLMNs. E. The configured NSSAI conveys the same information regardless of the PLMN the UE is accessing (e.g., this may be possible for NSSAI including only standardized S-NSSAI). When providing the requested NSSAI to the network upon registration, the UE of the given PLMN may only use the S-NSSAI belonging to the configured NSSAI if the corresponding PLMN is present.

If the registration procedure of the UE is successfully completed, the UE may obtain from the AMF an allowed NSSAI for this PLMN that may include one or more S-NSSAIs. The allowed NSSAI may take precedence over the NSSAI configured for this PLMN. The UE may only need to use the allowed NSSAI S-NSSAI corresponding to the network slice for the subsequent nNtwork Slice selection procedure of the serving PLMN.

For each PLMN, the UE may store the configured NSSAI and store the NSSAI if allowed. When the UE receives the allowed NSSAI for the PLMN, the UE may have to store the PLMN and override the previously stored allowed NSSAI for this PLMN.

Setting up a user plane connection to a data network via a network slice instance can be configured in two steps.

- Perform RM procedures to select AMFs that support the required network fragments

Establishing one or more PDU sessions in the requested data network via the network slice instance (s)

Serving AMF Selection to Support Network Slice

Enroll in a network engraving set

UE with NSSAI configured or allowed for PLMN

When the UE registers with the PLMN, if the UE for this PLMN has a configured NSSAI or allowed NSSAI f, the UE sends a request (for example, for the UE) to the network of the RRC and the NAS layer NSSAI may be required. If a temporary user ID has been assigned to the UE, in addition to the temporary user ID, it may include the slice (s) the UE wishes to register.

The requested NSSAI may be one of the following:

A configured NSSAI or a subset thereof if the UE does not have an NSSAI granted to the current PLMN; or

- if the UE has an NSSAI allowed for the current PLMN, the allowed NSSAI or a subset thereof,

- the permitted NSSAI or a subset thereof as described below and one or more S-NSSAIs of the NSSAI that have not been previously permanently denied (as defined below) and have no corresponding S-NSSAI in the accepted NSSAI Can be selected by the network.

The subset of NSSAIs that are configured may consist of a combination of S-NSSAIs, including one or more S-NSSAI (s) of configured NSSAIs to which S-NSSAIs are applied to this PLMN. And may have been previously added by the UE in the requested NSSAI.

The subset of allowed NSSAIs may consist of a combination of S-NSSAIs containing one or more S-NSSAIs in the last allowed NSSAI for this PLMN.

The UE may provide the requested NSSAI with the S-NSSAI from the Configured NSSAI that the UE previously provided for the serving PLMN in the current registration area.

The UE may need to include the requested NSSAI in the RRC connection setup and the NAS message. The RAN may need to route the NAS signal between the selected AMF using the requested NSSAI obtained during the UE and RRC connection establishment. If the RAN can not select the AMF based on the requested NSSAI, the NAS signal can be routed from the set to the AMF.

Upon successful registration, the UE is provided with a temporary ID by the serving AMF. The UE may have to include this temporary ID in all RRC connection settings during subsequent initial access so that the RAN can route the NAS signaling between the UE and the appropriate AMF.

The serving PLMN may also return a new granted NSSAI that identifies the network slice allowed by the serving PLMN for the UE. The UE may store this new allowed NSSAI and ignore the previously stored allowed NSSAI for this PLMN.

The network may individually reject the S-NSSAI provided by the UE in the NSSAI requested for the rejected reason. The network may also determine whether the rejection is permanent (e.g., the S-NSSAI is at least not supported by the PLMN in the current registration area) or transient (e.g., the nNetwork slide corresponding to S-NSSAI is temporarily unavailable) Lt; / RTI >

Upon receiving a Requested NSSAI and a Temporary ID in the RRC from the UE, the RAN can send a request to the AMF if the RAN can reach the AMF corresponding to the Temporary ID. Otherwise, the RAN may select the appropriate AMF based on the requested NSSAI provided by the UE and send the request to the selected AMF. If the RAN can not select an AMF based on the requested NSSAI, the request is sent in the default AMF.

UE without NSSAI for PLMN

When the UE registers with the PLMN, the RAN may have to route all of this UE signaling to / from the default AMF from the UE if the UE does not have a configured NSSAI or allowed NSSAI for this PLMN. The UE MUST NOT indicate the NSSAI in the RRC connection establishment or initial NAS message unless there is an NSSAI configured for that PLMN or an allowed NSSAI. If registration is successful, the UE is provided with a temporary ID by the AMF in the subscriber PLMN and an allowed NSSAI that identifies the slice allowed by the serving PLMN for the UE that is part of the subscribed default S-NSSAI (s). . ≪ / RTI > The UE may have to include this temporary ID in all RRC connection settings during subsequent initial access so that the RAN can route the NAS signaling between the UE and the appropriate AMF.

Modification of the network slice set for the UE

The set of network slices for the UE may be changed at any time while the UE is registered in the network and may be initiated by the network or UE, which is done under certain conditions as described below.

A network based on local policies, subscription changes, and / or UE mobility may change the set of allowed network slice (s) to which the UE is registered. The network may trigger such a change during the registration procedure or trigger a notification to the UE about a change in the supported network slice using an RM procedure (which may trigger the registration procedure). The network may provide a new allowed NSSAI and a list of tracking areas to the UE.

It may be necessary to define the details of the RM procedure used to inform the UE of a change in the supported NSSAI.

In order to change the set of S-NSSAIs used, the UE may have to start the registration procedure.

The change in the S-NSSAI set in which the UE is registered (UE or network initiated) may result in an AMF change in accordance with the operator policy.

Support for AMF relocation due to network slice

During the registration process of the PLMN, if the network determines that the network should be serviced by a different AMF based on the network slice aspect, the AMF that received the registration request first must retransmit the registration request to the other AMF. AMF < / RTI > The redirection message sent by the AMF over the RAN may need to include information for selecting a new AMF to serve the UE.

For UEs already registered, the system may have to support redirection initiated from the serving AMF to the target AMF by the UE ' s network due to network slice considerations. The operator policy can determine whether redirection between AMFs is allowed.

Establish a connection PDU session for the required network slice instance

Setting up a PDU session for a DN on a network slice may allow data to be sent over a network slice. The data network may be connected to S-NSSAI and DNN.

The network operator may provide a network slice selection policy (NSSP) to the UE. The NSSP may include one or more NSSP rules each associating an application with one S-NSSAI. Basic rules may also be included to match all applications with the S-NSSAI. When a UE application associated with a particular S-NSSAI requests data transmission,

If the UE has one or more PDU sessions established in response to a particular S-NSSAI, the UE may route user data of this application in one of these PDU sessions, as long as the other conditions of the UE do not prohibit the use of these PDU sessions . If the application provides a DNN, the UE may also decide which PDU session to use considering this DNN. If the UE does not have a PDU session established with this particular S-NSSAI, the UE may request a new PDU session corresponding to this S-NSSAI and a DNN that can be provided by the application. In order for the RAN to select the appropriate resources to support network slicing in the RAN, the RAN needs to recognize the network slice used by the UE.

AMF can choose SMF from the network slice instance based on S-NSSAI, DNN and other information. When the UE triggers the establishment of a PDU session, it may include a UE subscription and a local operator policy. The selected SMF can establish a PDU session based on the S-NSSAI and DNN.

NRF

The NF Storage Facility (NRF) can support the following functions:

- It can support service search function. It is possible to receive NF discovery requests from NF instances and to discovery and provide information to the NF instances of the discovery NF instances.

Network feature discovery and selection

NF Discovery can allow one NF to discovery a particular target NF type.

Unless the expected NF information is locally configured in the requestor NF, for example. The expected NF may be in the same PLMN where NF discovery is implemented via the NRF. The NF repository function (NRF) can be a logical function used to support the functionality of NF discovery.

The requestor NF may initiate NF discovery by providing the type of NF (e.g., SMF, PCF) and other service parameters in order not to access the associated NF stored in the requested type NF and the requestor NF. The target NF can be disassembled by slicing the related information.

The NRF may provide the IP address or FQDN of the NF instance to the requestor NF for selection of the target NF instance. Based on this information, the requestor NF may be able to select one NF instance.

The requestor NF may provide the NRF with the PLMN ID of the NF for the NF discovery via the PLMN. The local PLMN may interact with the NRF of the target PLMN to retrieve the IP address or FQDN of the target NF instance.

NRF Service

"NF Discovery" service

Service Description: The requestor NF can provide the IP address or FQDN of the expected NF instance.

Input: The NF type of the target NF, the NF type of the requestor NF, the PLMN ID of the PLMN target to which the NF belongs, and the service-related information.

Output: A set of target NF instances.

The service procedure may be as shown in Fig.

At step 1410, Requester-A may have to discovery the expected NF instance. For example, the AMF may request to retrieve an SMF instance from the same PLMN. Requester-A sends an NF Discovery Request to the NRF of the same PLMN. Expected NF The NF type of the instance, the NF type of the requestor, information about the network slice (optional), and other service-related parameters.

In step 1420, the NRF may grant an NF Discovery Request. Depending on the expected NF profile and the type of requestor NF, the NRF may determine whether the requestor NF is able to discovery the expected NF instance. Once the expected NF instance (s) are placed on one network slice, the NRF can accept the discovery request according to the discovery configuration of the network slice. The expected NF instance can only be retrieved by the NF of the same network slice.

In step 1430, if allowed, the NRF may determine the discovery NF instance and provide information about the set of discovery NF instances to the applicant via the NF Discovery Response message. The information of the discovery NF instance may include the following: The FQDN or IP address of the expected NF instance.

If the requester needs to discovery the NF in another PLMN, the NRF providing the PLMN may have to request the "NF Discovery" service from the NRF of the remote PLMN. The procedure can be shown in Fig.

At step 1510, the Requester-B NF may have to discovery the NF instance in the remote PLMN. For example, the AMF may request to retrieve the SMF instance from the remote PLMN. The requestor may send an NF Discovery Request to the NRF and the expected NF of the NF type, remote PLMN ID may be included in the NF Discovery Request.

At step 1520, the NRF providing the PLMN service identifies the NRF in the remote PLMN based on the remote PLMN ID and requests the "NF Discovery" service in the NRF of the remote PLMN according to the procedure of FIG. 14 to obtain the expected NF instance ) To the remote PLMN. Since the NRF in the serving PLMN triggers "NF Discovery" on behalf of the Requester-B NF, the NRF of the serving PLMN does not replace the information of the service requestor NF, ie Requester-B NF, in the Discovery Request message. have.

At step 1530, the NRF serving the PLMN may provide information of the disjoint NF instance set in the NF Discovery Response message.

The embodiments described above may be implemented in hardware components, software components, and / or a combination of hardware components and software components. For example, the devices, methods, and components described in the embodiments may be implemented within a computer system, such as, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, such as an array, a programmable logic unit (PLU), a microprocessor, or any other device capable of executing and responding to instructions. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. The processing device may also access, store, manipulate, process, and generate data in response to execution of the software. For ease of understanding, the processing apparatus may be described as being used singly, but those skilled in the art will recognize that the processing apparatus may have a plurality of processing elements and / As shown in FIG. For example, the processing unit may comprise a plurality of processors or one processor and one controller. Other processing configurations are also possible, such as a parallel processor.

The software may include a computer program, code, instructions, or a combination of one or more of the foregoing, and may be configured to configure the processing device to operate as desired or to process it collectively or collectively Device can be commanded. The software and / or data may be in the form of any type of machine, component, physical device, virtual equipment, computer storage media, or device , Or may be permanently or temporarily embodied in a transmitted signal wave. The software may be distributed over a networked computer system and stored or executed in a distributed manner. The software and data may be stored on one or more computer readable recording media.

The method according to an embodiment may be implemented in the form of a program command that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions to be recorded on the medium may be those specially designed and configured for the embodiments or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

The components described in the embodiments may be implemented by a programmable logic device such as one or more DSP (Digital Signal Processor), a processor, a controller, an application specific integrated circuit (ASIC), and a field programmable gate array Logic Element, other electronic devices, and combinations thereof. ≪ RTI ID = 0.0 > At least some of the functions or processes described in the embodiments may be implemented by software, and the software may be recorded in a recording medium. The components, functions and processes described in the embodiments may be implemented by a combination of hardware and software.

Although the embodiments have been described with reference to the drawings, various technical modifications and variations may be applied to those skilled in the art. For example, it is to be understood that the techniques described may be performed in a different order than the described methods, and / or that components of the described systems, structures, devices, circuits, Lt; / RTI > or equivalents, even if it is replaced or replaced.

Claims (20)

A communication method of a communication apparatus for performing communication with a user terminal,
Receiving a predetermined request from the user terminal;
Selecting any one of a plurality of network slice instances (NSIs) in the communication device to be allocated to the user terminal based on the predetermined request; And
Selecting one of a plurality of network function instances (NFIs) included in the selected network slice instance to be allocated to the user terminal
Lt; / RTI >
The network slice instance
Wherein the network slice is an instantiated form of a network slice including one or more network functions and resources for providing a network service having a certain performance and characteristics to the user terminal. The method according to claim 1,
The step of selecting the network slice instance
And selects a network slice instance to be allocated to the user terminal based on NSSAI (Network Slice Selection Assistance Information) included in the predetermined request. 3. The method of claim 2,
The NSSAI
(a) Slice / Service Type (SST) requested by the user terminal or (b) Slice / Service Type and SD (Slice Differentiator) corresponding to the user terminal. The method of claim 3,
The slice / service type
Wherein the user terminal is expected to exhibit network activity in a service requested by the user terminal. The method of claim 3,
The SD
Service type so that when a plurality of network slice instances satisfying the slice / service type are selected, one of a plurality of network slice instances satisfying the slice / service type is selected, . The method of claim 3,
The SD
A subscription data of the user terminal, a QoS attribute of the plurality of network slice instances, and a terminal property. 3. The method of claim 2,
The step of selecting the network slice instance
Further comprising at least one of a network slice instance pre-assigned to the user terminal and a serving registration area of the user terminal to select a network slice instance to be allocated to the user terminal. The method according to claim 1,
The step of selecting the network function instance
Selecting a network function instance to be assigned to the user terminal based on a type of network function indicating a logical network identifier representing the selected network slice instance and a role performed by the network function instance. 9. The method of claim 8,
The step of selecting the network function instance
Wherein one network function instance is selected for each type of network function among a plurality of network function instances included in the selected network slice instance. 9. The method of claim 8,
The step of selecting the network function instance
Further selecting a network operator's policy providing the network slice instance to select a network function instance to assign to the user terminal. The method according to claim 1,
The step of selecting the network function instance
A serving network function repository function corresponding to the selected network slice instance is selected from a selection condition received from a source-network function instance (S-NFI) requesting a selection for the network function instance And selecting the network function instance based on the selected network function instance. The method according to claim 1,
The step of selecting the network function instance
A source-network function instance receiving a selectable NFI list (Network Function Instance list) from a serving network function repository function (NRF) corresponding to the selected network slice instance selects the network function instance, To the serving NRF. A communication method of a communication apparatus for performing communication with a user terminal,
Receiving a predetermined request from the user terminal;
Selecting any one of a plurality of network slice instances (NSIs) in the communication device to be allocated to the user terminal based on the predetermined request; And
Forwarding a response to the predetermined request to the user terminal in response to the selection of the network slice instance
Lt; / RTI >
The network slice instance
Wherein the network slice is an instantiated form of a network slice that includes at least one network function and resource for providing a network service having a certain performance and characteristics to the user terminal. 14. The method of claim 13,
The step of selecting the network slice instance
And selects a network slice instance to be allocated to the user terminal based on the NSSAI included in the predetermined request. 14. The method of claim 13,
Performing a relocation from the current AMF to a new AMF when a new AMF (a new AMF) more suitable than the current AMF is detected to provide the selected network slice instance to the user terminal;
Lt; / RTI > 14. The method of claim 13,
The Access and Mobility Management Function (AMF) and the Network Slice Selection Function (NSSF) included in the communication device
Wherein when a plurality of network slice instances are assigned to the user terminal, the plurality of network slice instances are shared by the plurality of network slice instances assigned to the user terminal. 1. A communication device for performing communication with a user terminal,
A processor; And
A memory including at least one instruction executable by the processor,
Lt; / RTI >
Wherein if the at least one instruction is executed in the processor, the processor receives a predetermined request from the user terminal and, based on the predetermined request, determines which of the plurality of network slice instances in the communication device to assign to the user terminal Selecting one of the plurality of network function instances included in the selected network slice instance to be allocated to the user terminal,
Wherein the network slice instance is an instantiated form of a network slice that includes one or more network functions and resources for providing network services having certain performance and characteristics to the user terminal. 18. The method of claim 17,
The processor
And selects a network slice instance to be allocated to the user terminal based on the NSSAI included in the predetermined request. 18. The method of claim 17,
The processor
Further comprising at least one of a network slice instance pre-allocated to the user terminal and a serving registration area of the user terminal to select a network slice instance to be allocated to the user terminal. A communication device comprising:
A processor; And
A memory including at least one instruction executable by the processor,
Lt; / RTI >
Wherein if the at least one instruction is executed in the processor, the processor receives a predetermined request from a user terminal and, based on the predetermined request, assigns to the user terminal a plurality of network slice instances defined in the communication device And transmits a response to the predetermined request to the user terminal corresponding to the selection of the network slice instance,
The network slice instance
Wherein the network slice is an instantiated form of a network slice including one or more network functions and resources for providing a network service having a certain performance and characteristics to the user terminal.

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