1. A target radio access network, RAN, node (3) comprising: at least one memory (1705); and at least one processor (1704) coupled to the at least one memory (1705) and configured to, during handover of a radio terminal (1) to the target RAN node (3) from a source radio access network, RAN, node (2), the source RAN node (2) and the target RAN node (3) connecting a core network node (5) supporting network slicing: receive (404), from the core network node (5), a handover request message including slice information about a network slice; create, in response to the handover request message, radio resource configuration information to be used by the radio terminal (1) after the handover; and transmit (405), to the core network node (5), a handover request acknowledge message containing the radio resource configuration information, the radio resource configuration information transmitted from the core network node (5) to the source RAN node (2).

2. The target RAN node (3) according to Claim 1, wherein the slice information includes: (a) identification information of the network slice selected for the radio terminal (1); (b) type information of the network slice selected for the radio terminal (1); or (c) identification information of a network node or a network function associated with the network slice selected for the radio terminal (1); or any combination thereof.

3. A radio terminal (1) comprising: at least one memory (1508); and at least one processor (1505) coupled to the at least one memory (1508) and configured to, during handover from a source radio access network, RAN, node (2) to which the radio terminal (1) is connected to a target radio access network, RAN, node (3), the source RAN node (2) and the target RAN node (3) connecting a core network node (5) supporting network slicing; receive (407), from the source RAN node (2), radio resource configuration information to be used by the radio terminal (1) after the handover, the radio resource configuration information transmitted from the core network node (5) to the source RAN node (2); and use the radio resource configuration information to connect the target RAN node (3). 4. The radio terminal (1) according to Claim 3, wherein the source RAN node (2) communicates with the core network node (5) directly.

5. A core network node (5) supporting network slicing comprising: at least one memory (1803); and at least one processor (1802) coupled to the at least one memory (1803) and configured to, during handover of a radio terminal (1) from a source radio access network, RAN, node (2) to which the radio terminal (1) is connected to a target radio access network, RAN, node (3), the source RAN node (2) and the target RAN node (3) connecting the core network node (5): receive (402), from the source RAN node (2), a handover required message to start a handover for the radio terminal (1); transmit (404), to the target RAN node (3), a handover request message including slice information about a network slice; receive (405) from the target RAN node (3) a handover request acknowledge message containing radio resource information; and forward (406) the radio resource information to the source RAN node (2).

6. The core network node (5) according to Claim 4, wherein the slice information includes: (a) identification information of the network slice selected for the radio terminal (1); (b) type information of the network slice selected for the radio terminal (1); or (c) identification information of a network node or a network function associated with the network slice selected for the radio terminal (1); or any combination thereof.

7. A method executed by a target radio access network, RAN, node (3), the method comprising: during handover of a radio terminal (1) to the target RAN node (3) from a source radio access network, RAN, node (2), receiving (404), from a core network node (5) supporting network slicing, a handover request message including slice information about a network slice, the source RAN node (2) and the target RAN node (3) connecting the core network node (5); creating, in response to the handover request message, radio resource configuration information to be used by the radio terminal (1) after the handover; and transmitting (405), to the core network node (5), a handover request acknowledge message containing the radio resource configuration information, the radio resource configuration information directly transmitted from the core network node (5) to the source RAN node (2).

8. A method executed by a radio terminal (1), the method comprising; during handover from a source radio access network, RAN, node (2) to which the radio terminal (1) is connected to a target radio access network, RAN, node (3), receiving (407), from the source RAN node (2), radio resource configuration information to be used by the radio terminal (1) after the handover, the radio resource configuration information transmitted from a core network node (5) to the source RAN node (2), the source RAN node (2) and the target RAN node (3) connecting the core network node (5) supporting network slicing; and using the radio resource configuration information to connect the target RAN node (3).

9. A method executed by a core network node (5) that supports network slicing, the method comprising: during handover of a radio terminal (1) from a source radio access network, RAN, node (2) to which the radio terminal (1) is connected to a target radio access network, RAN, node (3), the source RAN node (2) and the target RAN node (3) connecting the core network node (5): receiving (402), from the source RAN node (2), a handover required message to start a handover for the radio terminal (1); transmitting (404), to the target RAN node (3), a handover request message including slice information about a network slice; receiving (405) from the target RAN node (3) a handover request acknowledge message containing radio resource information; and forwarding (406) the radio resource information to source RAN node (2).

10. A program product storing a program comprising instructions, which when executed on a processor of an electronic device causes the processor to perform a method according to any one of Claims 7 to 9

Technical field
[0001]
The present disclosure relates to wireless communication systems, particularly to the handover of wireless terminals between different Radio Access Technologies (RATs).
Background technology
[0002]
The 3rd Generation Partnership Project (3GPP) started standardization work of the 5th generation mobile communication system (5G) for the introduction of the transition to 2020 as 3GPP Release 14 in 2016 (see Non-Patent Document 1). 5G is realized by a combination of continuous improvement and evolution of LTE and LTE-Advanced (enhancement / evolution) and innovative improvement and development by introducing a new 5G air interface (new Radio Access Technology (RAT)). It is supposed to be done. The new RAT is, for example, a frequency band higher than the frequency band (eg, 6 GHz or less) targeted by the continuous development of LTE / LTE-Advanced, such as a centimeter wave band of 10 GHz or more and a millimeter of 30 GHz or more. Supports wave bands.
[0003]
In this specification, the 5th generation mobile communication system is also referred to as the Next Generation (NextGen) System (NG System). The new RAT for the NG System is called New Radio (NR), 5G RAT, or NG RAT. The new radio access networks (Radio Access Network (RAN)) and core networks for the NG System are called NextGen RAN (NG RAN) and NextGen Core (NG Core), respectively. The wireless terminal (User Equipment (UE)) connected to the NG System is called NextGen UE (NG UE). Formal names such as RAT, UE, radio access network, core network, network entity (node), and protocol layer for NG System will be determined in the future as standardization work progresses.
[0004]
In addition, the term "LTE" used in this specification includes improvements and developments of LTE and LTE-Advanced to enable interworking with the NG System, unless otherwise specified. The improvements and developments of LTE and LTE-Advanced for interworking with the NG System are also called LTE-Advanced Pro, LTE +, or enhanced LTE (eLTE). In addition, "Evolved Packet Core (EPC)", "Mobility Management Entity (MME)", "Serving Gateway (S-GW)", and "Packet Data Network (PDN) Gateway (P-GW)" as used herein. Terms relating to LTE networks or logical entities, such as ")", include these improvements and developments to enable interworking with the NG System, unless otherwise noted. The improved EPC, MME, S-GW, and P-GW include, for example, enhanced EPC (eEPC), enhanced MME (eMME), enhanced S-GW (eS-GW), and enhanced P-GW (eP-GW). ) Also called.
[0005]
In LTE and LTE-Advanced, bearers for each QoS class and PDN connection are RAN (ie, Evolved Universal Terrestrial RAN) and core network (ie, Evolved Packet core (EPC)) for quality of service (QoS) and packet routing. )) Used in both. That is, in the Bearer-based QoS (or per-bearer QoS) concept, one or more Evolved Packet System (EPS) bearers are configured between the UE and the P-GW in the EPC, and multiple Evolved Packet System (EPS) bearers with the same QoS class. Service Data Flows (SDFs) are transferred through one EPS bearer that satisfies these QoS. An SDF is one or more packet flows that match an SDF template (i.e., packet filters) based on Policy and Charging Control (PCC) rules. Also, for packet routing, each packet sent through the EPS bearer identifies to which bearer (ie, General Packet Radio Service (GPRS) Tunneling Protocol (GTP) tunnel) this packet is associated with. ) Includes information for.
[0006]
On the other hand, in the NG System, it is considered that the radio bearer may be used in the NG RAN, but the bearer is not used in the NG Core and the interface between the NG Core and the NG RAN (Non-Patent Document). See 1). Specifically, PDU flows are defined instead of EPS bearer, and one or more SDFs are mapped to one or more PDU flows. The PDU flow between the NG UE and the user plane termination entity in NG Core (i.e., the entity equivalent to P-GW in EPC) corresponds to the EPS bearer in the EPS Bearer-based QoS concept. That is, the NG System adopts the Flow-based QoS (or per-flow QoS) concept instead of the Bearer-based QoS concept. In the Flow-based QoS concept, QoS is handled on a PDU flow basis. The association between the UE and the data network is called a PDU session. PDU session is a term equivalent to LTE and LTE-Advanced PDN connection (PDN connection). Multiple PDU flows can be configured in one PDU session.
[0007]
In this specification, like LTE and LTE-Advanced systems, an end-to-end bearer (eg, EPS bearer) is set between the UE and the edge node (eg, P-GW) in the core network. A system that adopts the Bearer-based QoS concept is called a "bearer-based system" or "bearer-based network". On the other hand, a system that does not use a bearer in the core network and the interface between the core network and RAN, such as the NG System, and adopts the Flow-based QoS concept is called a "bearer-less system" or "bearer-less network". As in the NG System described above, a wireless bearer may be used in the RAN of the bearer-less network. The term “bearer-less” is used, for example, with GTP-less, (PDN) connection-less, tunnel-less, (IP) flow-based, SDF-based, stream-based, or (PDU) session-based. In other words. However, in the present specification, the NG System may function as a bearer-based system and may support both flow-based transfer and bearer-based transfer of user data.
[0008]
Furthermore, it is also being considered that the NG System supports network slicing (see Non-Patent Document 1). Network slicing uses Network Function Virtualization (NFV) and software-defined networking (SDN) technologies to enable the creation of multiple virtualized logical networks on top of physical networks. Each virtualized logical network is called a network slice or network slice instance and contains logical nodes and functions for specific traffic. And used for signaling. NG RAN and / or NG Core have a Slice Selection Function (SSF). The SSF selects one or more network slices suitable for the NG UE based on the information provided by at least one of the NG UE and the NG Core.
[0009]
In Patent Document 1, the handover from the bearer-less network (eg, 5G) to the bearer-based network (eg, LTE) and the handover from the bearer-based network (eg, LTE) to the bearer-less network (eg, 5G) Includes disclosure regarding handover to. In the 5G to LTE handover shown in Patent Document 1, the source control node (ie, Access Control Server (ACS) / eMME) of the 5G core (NG Core) is the service flows of the bearer-less network (5G). Map QoS parameters to EPS-bearer-level QoS for bearer-based network (LTE). The QoS parameters for 5G service flows are, for example, DiffServ code point (DSCP) values. LTE EPS-bearer-level QoS is, for example, QoS class identifier (QCI) and allocation and retention priority (ARP). The mapping of DSCP values ​​to EPS bearers may be one-to-one or n-to-one. Source ACS / eMME sends APN information containing EPS-bearer-level QoS information to target MME. Target MME sets up GTP tunnels for UE according to the received APN information.
[0010]
Further, in the LTE to 5G handover shown in Patent Document 1, the source MME of the LTE core (ie, EPC) makes a forward relocation request including the necessary bearer context information to the target ACS of the 5G core (NG Core). Send to / eMME. target ACS / eMME maps QCI values ​​obtained from LTE (ie, source MME) to 5G QoS parameters (ie, DSCP values) and maps them to the 5G core (NG Core) forwarding node (ie, Mobility Gateway Access Router). Supply to (M-GW / AR) or Mobility Gateway Edge Router (M-GW / ER). As a result, Target ACS / eMME becomes the UE service flows (i.e., IP).Set up at least one Generic Routing Encapsulation (GRE) tunnel to send packets).
Prior art literature
Patent documents
[0011]
Patent Document 1: International Publication No. 2015/16039
Non-patent literature
[0012]
Non-Patent Document 1: 3GPP TR 23.799 V0.6.0 (2016-07) “3rd Generation Partnership Project; Technical Specification Group Services and System Aspects; Study on Architecture for Next Generation System (Release 14)”, July 2016
Outline of the invention
Problems to be solved by the invention
[0013]
The inventors of the present invention examined the handover between the NG System (5G) and the LTE System, and found some problems. For example, in Patent Document 1, during the handover procedure from the LTE System to the NG System, the Access Stratum (AS) layer setting or Non-Access Stratum (NAS) in which the network slice to which the UE after the handover is connected is target RAT (NG RAT) is set. ) It is not stated that it will be considered for the setting.
[0014]
Therefore, one of the objectives to be achieved by the embodiments disclosed herein is to set the AS layer or NAS layer of the target RAT in the handover from a network that does not support network slicing to a network that supports network slicing. To provide equipment, methods, and programs that contribute to doing so well. It should be noted that this object is only one of the purposes that the embodiments disclosed herein seek to achieve. Other objectives or issues and novel features will be apparent from the description or accompanying drawings herein.
Means to solve problems
[0015]
In one aspect, the target radio access network (RAN) node associated with the second network includes at least one memory and at least one processor coupled to said at least one memory. The at least one processor receives slice information from the core network regarding a network slice in the second network to which the wireless terminal is connected in the handover of the wireless terminal from the first network to the second network. In response to the reception of the slice information, the wireless terminal generates radio resource setting information to be used in the second network after handover, and the radio resource setting information is transmitted to the radio terminal via the first network. It is configured to send to.
[0016]
In one aspect, the source radio access network (RAN) node associated with the first network includes at least one memory and at least one processor coupled to said at least one memory. The at least one processor performs slice information regarding a network slice in the second network to which the wireless terminal is connected and the second network in the handover of the wireless terminal from the first network to the second network. It is configured to receive a message regarding handover including at least one of the radio resource setting information based on the network slice in the second network from the second network and transmit the message regarding the handover to the radio terminal.
[0017]
In one aspect, the wireless terminal includes at least one memory and at least one processor coupled to the at least one memory. In the handover from the first network to the second network to which the wireless terminal is connected, the at least one processor is used for slice information regarding a network slice in the second network and a network slice in the second network. It is configured to receive a message regarding handover including at least one of the radio resource setting information based on the radio access network (RAN) node of the first network.
[0018]
In one aspect, the core network node comprises at least one memory and at least one processor coupled to said at least one memory. The at least one processor transfers slice information about a network slice in the second network to which the wireless terminal is connected to the second network in the handover of the wireless terminal from the first network to the second network. It is configured to send to the associated Target Radio Access Network (RAN) node.
[0019]
In one aspect, the method at the target radio access network (RAN) node associated with the second network is
In the handover of the wireless terminal from the first network to the second network
Receiving slice information about the network slice in the second network to which the wireless terminal is connected from the core network,
In response to the reception of the slice information, the wireless terminal generates wireless resource setting information to be used in the second network after the handover, and
Sending the wireless resource setting information to the wireless terminal via the first network,
including.
[0020]
In one aspect, the method at the source radio access network (RAN) node associated with the first network is
In the handover of the wireless terminal from the first network to the second network
A message regarding handover including at least one of slice information regarding a network slice in the second network to which the radio terminal is connected and radio resource setting information based on the network slice in the second network. Receiving from the network and
Sending a message related to the handover to the wireless terminal,
including.
[0021]
In one aspect, the method in the wireless terminal is the slice information about the network slice in the second network and the slice information in the second network in the handover from the first network to the second network to which the wireless terminal is connected. The present invention includes receiving a message regarding handover including at least one of radio resource setting information based on a network slice from a radio access network (RAN) node of the first network.
[0022]
In one aspect, the method at the core network node is to provide slice information about a network slice in the second network to which the radio terminal is connected in the handover of the radio terminal from the first network to the second network. Includes sending to a target radio access network (RAN) node associated with two networks.
[0023]
In one aspect, the program includes an instruction group (software code) for causing the computer to perform the method according to the above aspect when it is read by the computer.
The invention's effect
[0024]
According to the above aspects, there is provided a device, a method, and a program that contribute to appropriately performing the AS layer setting or NAS layer setting of the target RAT in the handover from the network that does not support network slicing to the network that supports network slicing. can.
A brief description of the drawing
[0025]
FIG. 1 is a diagram showing a configuration example of a wireless communication network according to some embodiments.
FIG. 2 is a diagram showing a configuration example of a wireless communication network according to some embodiments.
FIG. 3A is a sequence diagram showing an example of an inter-RAT handover procedure from the LTE System to the NG System according to the first embodiment.
FIG. 3B is a sequence diagram showing an example of an inter-RAT handover procedure from the LTE System to the NG System according to the first embodiment.
FIG. 4A is a sequence diagram showing another example of the inter-RAT handover procedure from the LTE System to the NG System according to the first embodiment.
FIG. 4B is a sequence diagram showing another example of the inter-RAT handover procedure from the LTE System to the NG System according to the first embodiment.
FIG. 5 is a flowchart showing an example of a method performed by the core network according to the first embodiment.
FIG. 6 is a flowchart showing an example of a method performed by the target NR Node B (NR NB) according to the first embodiment.
FIG. 7 is a flowchart showing an example of a method performed by the source LTE eNB according to the first embodiment.
FIG. 8 is a flowchart showing an example of a method performed by a wireless terminal according to the first embodiment.
FIG. 9 is a sequence diagram showing an example of an inter-RAT handover procedure from the LTE System to the NG System according to the second embodiment.
FIG. 10 is a sequence diagram showing an example of an inter-RAT handover procedure from the LTE System to the NG System according to the second embodiment.
FIG. 11 is a sequence diagram showing an example of an inter-RAT handover procedure from the LTE System to the NG System according to the third embodiment.
FIG. 12 is a sequence diagram showing an example of an inter-RAT handover procedure from the LTE System to the NG System according to the third embodiment.
FIG. 13A is a sequence diagram showing an example of an inter-RAT handover procedure from the NG System to the LTE System according to the fourth embodiment.
FIG. 13B is a sequence diagram showing an example of an inter-RAT handover procedure from the NG System to the LTE System according to the fourth embodiment.
FIG. 14A is a sequence diagram showing another example of the inter-RAT handover procedure from the NG System to the LTE System according to the fourth embodiment.
FIG. 14B is a sequence diagram showing another example of the inter-RAT handover procedure from the NG System to the LTE System according to the fourth embodiment.
FIG. 15 is a block diagram showing a configuration example of a wireless terminal according to some embodiments.
FIG. 16 is a block diagram showing a configuration example of a base station according to some embodiments.
FIG. 17 is a block diagram showing a configuration example of a base station according to some embodiments.
FIG. 18 is a block diagram showing a configuration example of a core network node according to some embodiments.
[Fig. 19A] Fig. 19A is a diagram showing an example of the format of the Mobility from EUTRA command message.
[Fig. 19B] Fig. 19B is a diagram showing an example of the format of the Mobility from EUTRA command message.
[Fig. 20] Fig. 20 is a diagram showing an example of a Handover Required message format.
FIG. 21 is a diagram showing an example of the format of Source NR NB to Target NR NB Transparent Container.
[Fig. 22] Fig. 22 is a diagram showing an example of the format of Source NR NB to Target NR NB Transparent Container.
[Figure 23] Source NR NB to Target NR NB Transparent Container Former It is a figure which shows an example of the above.
[Fig. 24] Fig. 24 is a diagram showing an example of the format of Source NR NB to Target NR NB Transparent Container.
FIG. 25 (NR) is a diagram showing an example of the format of a Handover Request message.
FIG. 26 is a diagram showing an example of the format of a (NR) Handover Request message.
[Fig. 27] (NR) Fig. 27 is a diagram showing an example of the format of a Handover Request message.
[Fig. 28] Fig. 28 is a diagram showing an example of the format of Slice Information.
[Fig. 29] Fig. 29 is a diagram showing an example of the format of Session Endpoint ID.
FIG. 30 is a diagram showing an example of the format of a (NR) Handover Request Acknowledge message.
[Fig. 31] Fig. 31 is a diagram showing an example of the format of Target to Source Transparent Container.
FIG. 32 (NR) is a diagram showing an example of the format of Handover Request Acknowledge.
FIG. 33 is a diagram showing an example of the format of (NR) Handover Request Acknowledge.
[Fig. 34] Fig. 34 is a diagram showing an example of the format of Forwarding Address.
[Fig. 35] Fig. 35 is a diagram showing an example of the format of the S1AP Handover Command message.
[Fig. 36] Fig. 36 is a diagram showing an example of the format of an NG2AP Handover Command message.
Embodiment for carrying out the invention
[0026]
In the following, specific embodiments will be described in detail with reference to the drawings. In each drawing, the same or corresponding elements are designated by the same reference numerals, and duplicate description thereof will be omitted as necessary for the sake of clarification of the description.
[0027]
The plurality of embodiments described below can be implemented independently or in combination as appropriate. These plurality of embodiments have novel features that differ from each other. Therefore, these plurality of embodiments contribute to solving different purposes or problems, and contribute to different effects.
[0028]

FIG. 1 shows a configuration example of a wireless communication network according to some embodiments including the present embodiment. In the example of FIG. 1, the wireless communication network includes a wireless terminal (UE) 1, an LTE base station (ie, eNB) 2, a New Radio (NR) base station (ie, NR NodeB (NR NB)) 3, EPC4, and Includes NextGen (NG) Core5. UE1 has the ability to connect to LTE systems including LTE eNB2 and EPC4, and has the ability to connect to NextGen (NG) systems including NR NB3 and NG Core 5.
[0029]
In the example of FIG. 1, EPC4 is connected to NG Core5. Specifically, one or more nodes in EPC4 are connected to one or more nodes in NG Core 5 via a control plane interface. In some implementations, the MME in EPC4 may be connected via the control plane interface to a control node (ie, Control Plane Function (CPF) node) that has at least some of the functions of the MME in NG Core 5. good. Further, one or more nodes in EPC4 may be connected to one or more data nodes (i.e., User Plane Function (UPF) nodes) in NG Core 5 via a user plane interface. Here, the data node (UPF node) may be a node having at least a part of the functions of the S-GW. That is, the EPC 4 has been improved (enhanced) to interwork with the NG System including the NG Core 5, and may be called an eEPC.
[0030]
Similarly, the NR NB3 may be connected to one or more CPF nodes in the NG Core 5 via the control plane interface (e.g., NG2 interface). Further, the NR NB 3 may be connected to one or more UPF nodes in the NG Core 5 via a user plane interface (e.g., NG3 interface). Further, UE1 may be connected to one or more CPF nodes in NG Core 5 via a control plane interface (e.g., NG1 interface). Here, the NG1 interface is defined as a logical interface for transferring information on the NAS layer, and the information on the NAS layer is transmitted via the NG2 interface and the wireless interface (NG Uu) between NR NB3 and UE1. May be done.
[0031]
FIG. 2 shows another configuration example of the wireless communication network according to some embodiments including the present embodiment. In the example of FIG. 2, LTE eNB2 is connected to NG Core 5. That is, the LTE eNB2 is connected to the MME in the NG Core 5 or the control node (ie, CPF node) having at least a part of the function of the MME via the control plane interface (eg, NG2 interface), and is connected to the user plane interface. It is connected to the Serving Gateway (S-GW) in NG Core 5 or a data node (ie, UPF node) having at least a part of the function of S-GW via (eg, NG3 interface). In this way, LTE eNB 2 has been improved (enhanced) so as to be connected to NG Core 5, and may be called eLTE eNB. In some implementations, NG Core 5 may set up a virtualized network slice that provides logical EPC nodes and EPC functions. In some implementations, E-UTRAN containing LTE eNB2 and NG RAN containing NR NB3 may be connected to the same network slice. Alternatively, the E-UTRAN containing LTE eNB2 and the NG RAN containing NR NB3 may be connected to different network slices.
[0032]
In the examples of FIGS. 1 and 2, LTE eNB2 may be connected to NR NB3 by a direct base station-to-station interface (e.g., X3 interface). The direct base station interface may be used for signaling between LTE eNB2 and NR NB3, user packet transfer, or both. However, there does not have to be a direct inter-base station interface between LTE eNB2 and NR NB3.
[0033]
The NG System may include other interfaces in addition to the above-mentioned NG1, NG2, NG3 interfaces. Interfaces are also called reference points. NG RANs (between different NRs and NBs) may be connected via the NX2 interface. A CPF node having one or both of the Mobility Management Function (MMF) and the Session Management Function (SMF) is connected to the UPF node via a control plane interface (eg, NG4 interface). You may. Different UPF nodes may be connected via a user plane interface (e.g., NG9 interface). CPF nodes with different functions may be connected via the control plane interface. For example, a CPF node having an MMF and an SMF may be connected to a CPF node having a policy control function (PCF) via a control plane interface (e.g., NG7 interface). A CPF node having an MMF and an SMF may be connected to a node having a Subscriber Data Management (SDM) via a control plane interface (e.g., NG8 interface). The CPF node may be connected to a node having an application function (AF) via a control plane interface (e.g., NG5 interface). UPF nodes may be connected to an external or local data network (DN) via a user plane interface (e.g., NG6 interface). It should be noted that the SMF may include functions of user or terminal authentication, service or network slicing authorization. In addition, each of the above-mentioned network nodes is referred to, or they are collectively referred to as a network function (Network Function (s): NF (s)).
[0034]
In some implementations, the NG System, including NR NB3 and NG Core5, supports data transfer based on the Flow-based QoS (or per-flow QoS) concept described above. The NG System, including NR NB3 and NG Core5, may be further configured to support bearer-based forwarding with bearers per QoS class and per PDU session. The bearer of the NG System is set between a pair of network functions (Network Functions (NFs)), for example, between the user plane functions in NR NB3 and NG Core 5, or between two user plane functions in NG Core 5. You may. Alternatively, the bearer of the NG System may be configured via NR NB3 between the user plane functions within UE1 and NG Core5. The bearer of the NG System may be called the NG-EPS-bearer, and the wireless access bearer of the NG System may be called the NG-RAB. The bearer of the NG System can be used to forward multiple packet flows (PDU flows).
[0035]
NG-RAB is set between the wireless bearer set between UE1 (NG UE) and NR NB3 and the user plane function (eg, Edge Gateway (Edge GW)) in NR NB3 and NG Core 5. It may be composed of a bearer (eg, NG3 bearer). NG-EPS-bearer is a core network bearer (eg, NG9 bearer) set between NG-RAB and the user plane function in NG Core 5 (between eg, Edge GW and Data Network Gateway (DN GW)). ) And may be composed. Edge GW is a gateway to the radio access network and corresponds to the user plane function of LTE S-GW. However, unlike the LTE S-GW, UE1 may be connected to multiple Edge GWs in the NG System. DN GW is a gateway to an external network (i.e., Data Network) and corresponds to the user plane function of LTE P-GW. As with LTE P-GW, UE1 may be connected to a plurality of DN GWs in the NG System.

WE CLAIM:
1. A target radio access network, RAN, node (3) comprising:
at least one memory (1705); and
at least one processor (1704) coupled to the at least one memory (1705) and
configured to, during handover of a radio terminal (1) to the target RAN node (3) from a
source radio access network, RAN, node (2), the source RAN node (2) and the target RAN
node (3) connecting a core network node (5) supporting network slicing:
receive (404), from the core network node (5), a handover request message
including slice information about a network slice;
create, in response to the handover request message, radio resource
configuration information to be used by the radio terminal (1) after the handover; and
transmit (405), to the core network node (5), a handover request
acknowledge message containing the radio resource configuration information, the radio
resource configuration information transmitted from the core network node (5) to the source
RAN node (2).
2. The target RAN node (3) according to Claim 1, wherein the slice information
includes: (a) identification information of the network slice selected for the radio terminal (1);
(b) type information of the network slice selected for the radio terminal (1); or (c)
identification information of a network node or a network function associated with the
network slice selected for the radio terminal (1); or any combination thereof.
3. A radio terminal (1) comprising:
at least one memory (1508); and
at least one processor (1505) coupled to the at least one memory (1508) and
configured to, during handover from a source radio access network, RAN, node (2) to which
the radio terminal (1) is connected to a target radio access network, RAN, node (3), the source
RAN node (2) and the target RAN node (3) connecting a core network node (5) supporting
network slicing;
receive (407), from the source RAN node (2), radio resource configuration
information to be used by the radio terminal (1) after the handover, the radio resource
configuration information transmitted from the core network node (5) to the source RAN node
(2); and
use the radio resource configuration information to connect the target RAN node (3). 4. The radio terminal (1) according to Claim 3, wherein the source RAN node (2)
communicates with the core network node (5) directly.
5. A core network node (5) supporting network slicing comprising:
at least one memory (1803); and
at least one processor (1802) coupled to the at least one memory (1803) and
configured to, during handover of a radio terminal (1) from a source radio access network,
RAN, node (2) to which the radio terminal (1) is connected to a target radio access network,
RAN, node (3), the source RAN node (2) and the target RAN node (3) connecting the core
network node (5):
receive (402), from the source RAN node (2), a handover required message to start a
handover for the radio terminal (1);
transmit (404), to the target RAN node (3), a handover request message including
slice information about a network slice;
receive (405) from the target RAN node (3) a handover request acknowledge message
containing radio resource information; and
forward (406) the radio resource information to the source RAN node (2).
6. The core network node (5) according to Claim 4, wherein the slice information
includes: (a) identification information of the network slice selected for the radio terminal (1);
(b) type information of the network slice selected for the radio terminal (1); or (c)
identification information of a network node or a network function associated with the
network slice selected for the radio terminal (1); or any combination thereof.
7. A method executed by a target radio access network, RAN, node (3), the method
comprising:
during handover of a radio terminal (1) to the target RAN node (3) from a source
radio access network, RAN, node (2), receiving (404), from a core network node (5)
supporting network slicing, a handover request message including slice information about a
network slice, the source RAN node (2) and the target RAN node (3) connecting the core
network node (5);
creating, in response to the handover request message, radio resource configuration
information to be used by the radio terminal (1) after the handover; and transmitting (405), to the core network node (5), a handover request acknowledge
message containing the radio resource configuration information, the radio resource
configuration information directly transmitted from the core network node (5) to the source
RAN node (2).
8. A method executed by a radio terminal (1), the method comprising;
during handover from a source radio access network, RAN, node (2) to which the
radio terminal (1) is connected to a target radio access network, RAN, node (3), receiving
(407), from the source RAN node (2), radio resource configuration information to be used by
the radio terminal (1) after the handover, the radio resource configuration information
transmitted from a core network node (5) to the source RAN node (2), the source RAN node
(2) and the target RAN node (3) connecting the core network node (5) supporting network
slicing; and
using the radio resource configuration information to connect the target RAN node
(3).
9. A method executed by a core network node (5) that supports network slicing, the
method comprising:
during handover of a radio terminal (1) from a source radio access network, RAN,
node (2) to which the radio terminal (1) is connected to a target radio access network, RAN,
node (3), the source RAN node (2) and the target RAN node (3) connecting the core network
node (5):
receiving (402), from the source RAN node (2), a handover required message to start
a handover for the radio terminal (1);
transmitting (404), to the target RAN node (3), a handover request message including
slice information about a network slice;
receiving (405) from the target RAN node (3) a handover request acknowledge
message containing radio resource information; and
forwarding (406) the radio resource information to source RAN node (2).
10. A program product storing a program comprising instructions, which when
executed on a processor of an electronic device causes the processor to perform a method
according to any one of Claims 7 to 9