TECHNICAL FIELD

[0001 ] The present disclosure relates to methods and operations by network nodes and user equipments in a wireless communications system.

BACKGROUND

[0002] The 3GPP release 15 introduces New Radio (NR) and the dual connectivity from the early releases is expanded to cover the dual connectivity between a Long-Term Evolution (LTE) node and NR node, or between two NR nodes, such as shown in Figure 1. Further one Protocol Data Unit (PDU) session may be split in User Plane Function (UPF), so one part of the PDU session goes via one node and the rest of the PDU session goes via another node. The security keys of the Master Cell Group (MCG) bearer, Split bearer, and SCG bearer are configurable per bearer. For example, the security keys may comprise a eNB key (KeNB) or a secondary eNB key (S-KeNB).

[0003] With NR, the PDU session contains Quality of Service (QoS) flows. The QoS flows are mapped by the Radio Access Network (RAN) into radio bearers, there will be no one to one mapping.

Potential Problems with Existing Solutions

[0004] The current Dual Connectivity is built on the assumption that a single Service

Data Adaptation Protocol/Packet Data Convergence Protocol (SDAP/PDCP) entity exists per PDU session. The PDU session is only split in RAN, but not in user-plane function (UPF). This has to be changed now so that two SDAP/PDCP entities, one in each node may exist simultaneously.

[0005] Further it is not clear which RAN will decide the mapping of the QoS flows to radio bearers in case of Dual Connectivity and how such mapping would be decided.

[0006] One related problem is how to handle the situation when the Master NG-RAN node (M-NG-RAN) node decides to offer resources to the Secondary NG-RAN node (S-NG-RAN) for handling of flows assigned to the SDAP entities hosted by the S-NG-RAN. SUMMARY

[0007] According to some embodiments of inventive concepts, a method of operating a network node to provide dual connectivity in a new radio telecommunications system is provided. The method includes allocating two tunnel endpoint identifiers (TEIDs). The method also includes sending the allocated TEIDs to at least one other network node for transporting a Protocol Data Unit (PDU) session that can be split. The method further includes receiving two TEIDs for a master node and a secondary node.

[0008] A potential advantage of these and other embodiments disclosed herein is that it is operationally possible to use a Master Cell Group resource when a single Service Data Adaptation Protocol/Packet Data Convergence Protocol (SDAP/PDCP) is located in a Secondary NG-RAN (S-NG-RAN) node. Another potential advantage of these and other embodiments disclosed herein is that the PDU session may be split in both the RAN and in the UPF. A further potential advantage of these and other embodiments disclosed herein is that two SDAP/PDCP entities, one in each node, may exist simultaneously.

[0009] Some other embodiments are directed to a network node for providing dual connectivity in a new radio telecommunications system. The network node is configured to allocate two TEIDs, send the allocated TEIDs to at least other network node for transporting a PDU session that can be split, and receive two TEIDs for a master node and a secondary node.

[0010] According to some other embodiments of inventive concepts, a method of operating a master node provides dual connectivity is provided. The method includes sending a secondary node addition request message to a secondary node, SN. The method further includes sending a SN add/modify completion indication to the SN that informs the SN that the operations to add/modify are complete.

[001 1 ] Some other embodiments are directed to a master node that provides dual connectivity. The master node is configured to send a secondary node addition request message to as secondary node (SN) and send a SN add/modify completion indication to the SN that informs the SN of that the operations to add/modify are complete.

[0012] According to some other embodiments of inventive concepts, a method of operating a master node to provide dual connectivity is provided. The method includes receiving two tunnel point identifiers, TEIDs, in a request for a PDU session that can be split. The method also includes allocating a TEID for a master node and receiving a TEID allocated by a secondary node to transport the PDU session. The method further includes sending the allocated TEIDs to the core network. [0013] Some other embodiments are directed to master node that provides dual connectivity. The master node is configured to receive two tunnel point identifiers, TEIDs, in a request for a PDU session that can be split. The master node is also configured to allocate a TEID for a master node and receive a TEID allocated by a secondary node to transport the PDU session. The master node is further configured to send the allocated TEIDs to the core network.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in a constitute a part of this application, illustrate certain non-limiting embodiments of inventive concepts. In the drawings:

[0015] Figure 1 illustrates a block diagram dual connectivity between a LTE node and a NR node, or between two NR nodes in accordance with some embodiments of the inventive concepts described herein;

[0016] Figure 2 illustrates a data flow diagram of a new message that is sent by a

M-NG-RAN node to inform a S-NG-RAN node of a success operation of a S-NG-RAN node addition completion procedure in accordance with some embodiments of the inventive concepts described herein;

[0017] Figure 3 illustrates a combined data flow diagram and flowchart of operations of a method of operating a network node to provide dual connectivity in a new radio telecommunications system in accordance with some embodiments of the inventive concepts described herein;

[0018] Figure 4 illustrates a table of information elements (IEs) used for a PDU Session

Setup Request Transfer in accordance with some embodiments of the inventive concepts described herein;

[0019] Figure 5 illustrates a block diagram illustrating elements of a user equipment

(UE) configured to operate according to embodiments of the inventive concepts described herein;

[0020] Figure 6 illustrates a block diagram illustrating elements of a network node configured to operate according to one or more embodiments of the inventive concepts described herein;

[0021 ] Figure 7 illustrates a flowchart of operations performed by a network node to provide dual connectivity in a new radio telecommunications system in accordance with some embodiments of the inventive concepts described herein; and [0022] Figure 8 illustrates a flowchart of operations performed by a master node to provide dual connectivity in accordance with some embodiments of the inventive concepts described herein.

DETAILED DESCRIPTION

[0023] Inventive concepts will now be described more fully hereinafter with reference to the accompanying drawings, in which examples of embodiments of inventive concepts are shown. Inventive concepts may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of present inventive concepts to those skilled in the art. It should also be noted that these embodiments are not mutually exclusive. Components from one embodiment may be tacitly assumed to be present/used in another embodiment. Any two or more embodiments described below may be combined in any way with each other. Moreover, certain details of the described embodiments may be modified, omitted, or expanded upon without departing from the scope of the described subject matter.

[0024] Various embodiments of the present disclosure are directed to performing QoS flow to data radio bearer (DRB) mapping if the Service Data Adaptation Protocol (SDAP) is hosted in the S-NR-RAN NODE, and the master node (MN) may provide the share it is willing to take with master cell group (MCG) resources for the overall QoS that is required. The S-NG-RAN node decides how the QoS flow should be mapped, and the M-NG-RAN node informs the S-NG-RAN node of information related to the completion, e.g. informs the S-NG-RAN node of the transport layer address. The M-NG-RAN node informs the

S-NG-RAN node that the MCG resource addition is completed and provides back the needed information which can include, for example, the transport layer address.

[0025] Figure 2 shows a new message that is sent by the M-NG-RAN node to inform the S-NG-RAN node of success operation of the S-NG-RAN node addition completion procedure. The purpose of the S-NG-RAN node addition completion procedure is to complete, if applicable, the setup Xn-U transport bearers. The procedure can use UE-associated signaling.

[0026] Referring to Figure 2, the M-NG-RAN node sends (step 200) a S-NODE

ADDMODIFY COMPLETE message to the S-NG-RAN node that informs the S-NG-RAN node that the operations to add/modify (add and/or modify) are complete. The message can further contain information that informs the S-NG-RAN node of the transport layer address. The S-NODE ADDMODIFY COMPLETE message may contain a Xn-U GTP-U tunnel endpoint information to complete the Xn-U tunnel establishment for DRBs for which the NR PDCP entity is hosted by the S-NG-RAN node. The operations of Figure 2 may be used for TS 38.423.

[0027] Figure 3 shows a combined data flow diagram and flowchart of operations by a user equipment (UE), MN, SN, UPF, and AMF in accordance with some embodiments. Referring to Figure 3, the data flow diagram and flowchart illustrate how the new message operationally functions in the procedure to "add S-NG-RAN node." The operations of Figure 3 may be used for TS 37.340.

[0028] In step 1, the MN sends a SN addition request to the SN, which responds in step

2 with a SN addition request acknowledgment (e.g., carried in a SN RRC configuration message) to the MN. In step 2a, the MN sends a SN add/modify completion indication to the SN. If in step 2a, the MN needs to complete the setup of Xn-U transport resources towards the SN, it sends the SN AddModify Complete message to the SN.

[0029] In step 3, the MN sends a RRCConnectionReconfiguration indication (e.g., carried in a SN RRC configuration message) to the UE. In step 4, the UE responds with a RRCConnectionReconfigurationComplete indication (e.g., carried in a SN RRC configuration complete message).

[0030] In step 5, the MN sends a SN Reconfiguration Complete indication (e.g., carried in a SN RRC configuration complete message) to the SN. In step 7, the SN and the UE perform the Random Access Procedure.

[0031 ] In step 8, the UPF forwards data through the MN to the SN.

[0032] Steps 9, 10, 11, and 12 perform a path update procedure. In step 9, The MN sends a PDU session modification indication to the Access and Mobility Management Function (AMF). In step 10, the AMF responsively sends a bearer modification indication to the UPF. In step 11 , the UPF responsively sends an end marker packet indication to the MN, which sends it to the SN. In step 12, the AMF sends a PDU session modification confirmation indication to the MN.

[0033] Various embodiments of the present disclosure are further directed to operations for PDU session splitting at the UPF.

[0034] For one tunnel, one end is in UPF and the other end is in the NG-RAN node.

Two tunnels are needed when split in UPF. In some embodiments, the UPF first pre-allocates two tunnel endpoint identifiers (TEIDs), which it sends to the RAN. The RAN then, after processing, sends back the TEIDs at the RAN side, one for the master node (MN) and the other for the secondary node (SN). The RAN also knows by then the TEID at the UPF side. A 5G Core Network (5GC) can operate to allocate 2 TEIDs and, when a RAN does not perform splitting, the 5GC can responsively release one of the two TEIDs.

[0035] In some embodiments, a 5GC provides to the M-NG-RAN node two sets of transport layer information (e.g. Transport Layer Address, GTP-U TEIDs) for the PDU sessions for which UPF splitting should be supported. The M-NG-RAN node operates to perform the UPF splitting of the PDU sessions. The M-NG-RAN node sends feedback on the PDU session splitting information and the transport layer information for, or of, the master node (MN) and the S-NG-RAN node. In one embodiment, the additional transport layer information for the S-NG-RAN node is provided by the 5GC in a PDU session resource setup request and/or in by the 5GC in a PDU session resource modification request, such as shown in Figure 4.

[0036] Figure 4 illustrates a table of information elements (IEs) used for PDU Session

Setup Request Transfer, which may include step 9 in Figure 3. Any one or more of the IEs can be transparent to the AMF. In one embodiment, the Additional Transport Layer Information IE is a 5GC transport layer address for a split PDU session in the S-NG-RAN node. The PDU session type IE embodiment, the Additional Transport Layer Information IE may also be transparent to the AMF. In this or another embodiment, the PDU Session Type IE can indicate whether the session is IP unstructured or structured, e.g., Ethernet. The IEs in Figure 4 may be used in TS 38.413. The IEs in Figure 4 may also be used for TS 37.340.

[0037] In some alternative or additional embodiments, a 5GC operates to provide to a

M-NG-RAN node information directed to how the QoS flows in the PDU session should be split, and also provides the transport layer information. The M-NG-RAN node can operate to decide the final split and inform, e.g., to the 5GC, of the PDU session splitting information and the transport layer information for, or of, the M-NG-RAN node and the S-NG-RAN node.

[0038] In some alternative or additional embodiments, a M-NG-RAN node operates to decide and inform the 5GC that the PDU session will be split in UPF. The 5GC then provides the transport layer information for the S-NG-RAN node afterwards.

Potential Advantage

[0039] A potential advantage of these and other embodiments disclosed herein is that it is operationally possible to use the MCG resource when SDAP/PDCP is located in the S-NG-RAN node. Terminology:

[0040] In some embodiments, a more general term "network node" is used and it can correspond to any type of radio network node or any network node, which communicates with a UE and/or with another network node. Examples of network nodes are MN, SN, UPF, and AMF. Example network nodes may further include NodeB, MeNB, SeNB, a network node belonging to MCG or SCG, base station (BS), multi-standard radio (MSR) radio node such as MSR BS, eNodeB, network controller, radio network controller (RNC), base station controller (BSC), relay, donor node controlling relay, base transceiver station (BTS), access point (AP), transmission points, transmission nodes, RRU, RRH, nodes in distributed antenna system (DAS), core network node (e.g. MSC, MME, etc.), O&M, OSS, SON, positioning node (e.g. E-SMLC), MDT, etc.

[0041 ] In some embodiments, the non-limiting term user equipment (UE) is used and it refers to any type of wireless device communicating with a network node and/or with another UE in a cellular or mobile communication system. Examples of UE are target device, device to device (D2D) UE, machine type UE or UE capable of machine to machine (M2M) communication, PDA, PAD, Tablet, mobile terminals, smart phone, laptop embedded equipped (LEE), laptop mounted equipment (LME), USB dongles, ProSe UE, V2V UE, V2X UE, etc.

[0042] In some embodiments, the non-limiting term WAN (wireless access network or

RAN, radio access network) node is used. The WAN node can be a UE (e.g. D2D UE) or a network node (e.g. access point, BS etc.). The WAN node is also interchangeably called as cellular node, NW source node etc.

[0043] The term time resource used herein may correspond to any type of physical resource or radio resource expressed in terms of length of time. Examples of time resources are: symbol, time slot, subframe, radio frame, TTI, interleaving time etc.

[0044] The embodiments are described for 5G. However, the embodiments are applicable to any Radio Access Technology (RAT) or multi-RAT systems, where the UE receives and/or transmit signals (e.g. data) e.g. LTE FDD/TDD, WCDMA/HSPA,

GSM/GERAN, Wi Fi, WLAN, CDMA2000, 5G, NR, etc.

Example Elements of UE and Network Node:

[0045] Figure 5 is a block diagram illustrating elements of a UE 500 (also referred to as a wireless terminal, a wireless communication device, a wireless communication terminal, user equipment, a user equipment node/terminal/device, etc.) configured to operate according to embodiments disclosed herein. As shown, the UE 500 may include an antenna 507, and a transceiver circuit 501 (also referred to as a transceiver) including a transmitter and a receiver configured to provide uplink and downlink radio communications with a base station of a radio access network. The UE 500 may also include at least one processor circuit 503 (also referred to as a processor) coupled to at least one transceiver circuit 501 (also referred to as a transceiver), and at least one memory circuit 505 (also referred to as memory) coupled to the processor circuit. The memory 505 may include computer readable program code that when executed by the processor 503 causes the processor 53 to perform operations according to embodiments disclosed herein for a UE. According to other embodiments, processor 503 may be defined to include memory so that a separate memory circuit is not required. The UE 500 may also include an interface (such as a user interface) coupled with processor 503.

[0046] As discussed herein, operations of the UE 500 may be performed by processor

503 and/or transceiver 501. Moreover, modules may be stored in memory 505, and these modules may provide instructions so that when instructions of a module are executed by processor 503, processor 503 performs respective operations according to one or more embodiments herein.

[0047] Figure 6 is a block diagram illustrating elements of a network node 600 which may correspond to any one or more of the MN, SN, UPF, and AMF configured to operate according to one or more embodiments disclosed herein. As shown, the network node 600 may include at least one transceiver circuit 601 (also referred to as a transceiver) including a transmitter and a receiver configured to provide uplink and downlink radio communications with UEs. The network node 600 may include at least one network interface circuit 607 (also referred to as a network interface) configured to provide communications with other network nodes. The network node 600 may also include at least one processor circuit 603 (also referred to as a processor) coupled to the transceiver 601, and at least one memory circuit 605 (also referred to as memory) coupled to the processor 603. The memory 605 may include computer readable program code that when executed by the processor 603 causes the processor 603 to perform operations according to embodiments disclosed herein for a network node. According to other embodiments, processor 603 may be defined to include memory so that a separate memory circuit is not required.

[0048] As discussed herein, operations of the network node 600 may be performed by processor 603, network interface 607, and/or transceiver 601. For example, processor 603 may control transceiver 601 to transmit communications through transceiver 601 over a radio interface to one or more UEs and/or to receive communications through transceiver 601 from one or more UEs over a radio interface. Similarly, processor 603 may control network interface 607 to send communications through network interface 607 to one or more other network nodes and/or to receive communications through network interface 607 from one or more other network nodes. Moreover, modules may be stored in memory 605, and these modules may provide instructions so that when instructions of a module are executed by processor 603, processor 603 performs respective operations (e.g., operations discussed below with respect to example embodiments of network nodes).

[0049] In some embodiments, some or all of the operations described herein may be implemented as virtual components executed by one or more virtual machines implemented in one or more virtual environments hosted by one or more of network nodes. Further, in embodiments in which the virtual node is not a radio access node or does not require radio connectivity (e.g., a core network node), then the network node may be entirely virtualized.

[0050] The operations may be implemented by one or more applications (which may alternatively be called software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc.) operative to implement some of the features, functions, and/or benefits of some of the embodiments disclosed herein. Applications are run in a virtualization environment which provides hardware comprising processing circuitry and memory. Memory contains instructions executable by processing circuitry whereby application is operative to provide one or more of the features, benefits, and/or functions disclosed herein.

Operational Embodiments:

[0051 ] Figure 7 is a flowchart of operations that can be performed by a network node to provide dual connectivity in a new radio telecommunications system in accordance with some embodiments. Referring to Figure 7, the network node allocates 700 two tunnel endpoint identifiers, TEIDs. The network node sends 702 the allocated TEIDs to at least other network node for transporting a Protocol Data Unit, PDU, session that can be split. The network node receives 704 two TEIDs for a master node and a secondary node.

[0052] The network node may be a User Plane Function, UPF. The network node may further operation to, responsive to determining that the allocated TEIDs have not been used for transport of a split PSU session, release one of the two TEIDs for use for transporting another PDU session. The allocated TEIDs may be GTP-U TEIDs, and the allocated TEIDs may be sent to a master node, which may be a Master NG-RAN node.

[0053] Figure 8 is a flowchart of operations that can be performed by a master node to provide dual connectivity in accordance with some embodiments. Referring to Figure 8, the master node sends 800 a secondary node addition request message to as secondary node, SN. The master node then sends 802 a SN add/modify completion indication to the SN that informs the SN of that the operations to add/modify are complete.

[0054] The SN add/modify completion indication may inform the SN that a Master

Cell Group resource addition is complete. The SN add/modify completion indication may inform the SN of a transport layer address associated with the Master Cell Group resource that was added. The SN add/modify completion indication may be a S-NODE ADDMODIFY COMPLETE message. The S-NODE ADDMODIFY COMPLETE message may contain a Xn-U GTP-U tunnel endpoint information to complete Xn-U tunnel establishment for Data Radio Bearers for which New Radio Packet Data Convergence Protocol is hosted by the secondary node. The secondary node may be a Secondary NG-RAN node.

Abbreviations:

[0055] At least some of the following abbreviations may be used in this disclosure. If there is an inconsistency between abbreviations, preference should be given to how it is used above. If listed multiple times below, the first listing should be preferred over any subsequent listing(s).

Primary Abbreviations:

5GC 5G Core Network

AMF Access and Mobility Management Function

DC Dual Connectivity

DRB Data Radio Bearer

PDCP Packet Data Convergence Protocol

PDU Protocol Data Unit

MCG Master Cell Group

MN Master Node (M-NG-RAN node)

M-NG-RAN node Master NG-RAN node

NR New Radio, 5G

SDAP Service Data Adaptation Protocol

SN Secondary Node (S-NG-RAN node)

S-NG-RAN node Secondary NG-RAN node

UPF User Plane Function

Secondary Abbreviations: lx RTT CDMA2000 lx Radio Transmission Technology

3GPP 3rd Generation Partnership Project

5G 5th Generation

ABS Almost Blank Subframe

ARQ Automatic Repeat Request

AWGN Additive White Gaussian Noise

BCCH Broadcast Control Channel

BCH Broadcast Channel

CA Carrier Aggregation

CC C airier Component

CCCH SDU Common Control Channel SDU

CDMA Code Division Multiplexing Access

CGI Cell Global Identifier

CIR Channel Impulse Response

CP Cyclic Prefix

CPICH Common Pilot Channel

CPICH Ec/No CPICH Received energy per chip divided by the power density in the band

CQI Channel Quality information

C-RNTI Cell RNTI

CSI Channel State Information

DCCH Dedicated Control Channel

DL Downlink

DM Demodulation

DMRS Demodulation Reference Signal

DRX Discontinuous Reception

DTX Discontinuous Transmission

DTCH Dedicated Traffic Channel

DUT Device Under Test

E-CID Enhanced Cell-ID (positioning method)

E-SMLC Evolved-Serving Mobile Location Centre

ECGI Evolved CGI

eNB E-UTRAN NodeB

ePDCCH enhanced Physical Downlink Control Channel E-SMLC evolved Serving Mobile Location Center

E-UTRA Evolved UTRA

E-UTRAN Evolved UTRAN

FDD Frequency Division Duplex

FFS For Further Study

GERAN GSM EDGE Radio Access Network

gNB Base station in NR

GNSS Global Navigation Satellite System

GSM Global System for Mobile communication

HARQ Hybrid Automatic Repeat Request

HO Handover

HSPA High Speed Packet Access

HRPD High Rate Packet Data

LOS Line of Sight

LPP LTE Positioning Protocol

LTE Long-Term Evolution

MAC Medium Access Control

MB MS Multimedia Broadcast Multicast Services

MBSFN Multimedia Broadcast multicast service Single Frequency Network

MBSFN ABS MBSFN Almost Blank Subframe

MDT Minimization of Drive Tests

MIB Master Information Block

MME Mobility Management Entity

MSC Mobile Switching Center

NPDCCH Narrowband Physical Downlink Control Channel

OCNG OFDMA Channel Noise Generator

OFDM Orthogonal Frequency Division Multiplexing

OFDMA Orthogonal Frequency Division Multiple Access

OSS Operations Support System

OTDOA Observed Time Difference of Arrival

O&M Operation and Maintenance

PBCH Physical Broadcast Channel

P-CCPCH Primary Common Control Physical Channel

PCell Primary Cell PCFICH Physical Control Format Indicator Channel

PDCCH Physical Downlink Control Channel

PDP Profile Delay Profile

PDSCH Physical Downlink Shared Channel

PGW Packet Gateway

PHICH Physical Hybrid-ARQ Indicator Channel

PLMN Public Land Mobile Network

PMI Precoder Matrix Indicator

PRACH Physical Random Access Channel

PRS Positioning Reference Signal

PSS Primary Synchronization Signal

PUCCH Physical Uplink Control Channel

PUSCH Physical Uplink Shared Channel

RACH Random Access Channel

QAM Quadrature Amplitude Modulation

RAN Radio Access Network

RAT Radio Access Technology

RLM Radio Link Management

RNC Radio Network Controller

RNTI Radio Network Temporary Identifier

RRC Radio Resource Control

RRM Radio Resource Management

RS Reference Signal

RSCP Received Signal Code Power

RSRP Reference Symbol Received Power OR

Reference Signal Received Power

RSRQ Reference Signal Received Quality OR

Reference Symbol Received Quality

RSSI Received Signal Strength Indicator

RSTD Reference Signal Time Difference

SCH Synchronization Channel

SCell Secondary Cell

SDU Service Data Unit

SFN System Frame Number SGW Serving Gateway

SI System Information

SIB System Information Block

SNR Signal to Noise Ratio

SON Self Optimized Network

ss Synchronization Signal

sss Secondary Synchronization Signal

TDD Time Division Duplex

TDOA Time Difference of Arrival

TOA Time of Arrival

TSS Tertiary Synchronization Signal

TTI Transmission Time Interval

UE User Equipment

UL Uplink

UMTS Universal Mobile Telecommunication System

USIM Universal Subscriber Identity Module

UTDOA Uplink Time Difference of Arrival

UTRA Universal Terrestrial Radio Access

UTRAN Universal Terrestrial Radio Access Network

WCDMA Wide CDMA

WLAN Wide Local Area Network

Further Definitions and Embodiments:

[0056] In the above-description of various embodiments of the present disclosure, it is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0057] When an element is referred to as being "connected", "coupled", "responsive", or variants thereof to another element, it can be directly connected, coupled, or responsive to the other element or intervening elements may be present. In contrast, when an element is referred to as being "directly connected", "directly coupled", "directly responsive", or variants thereof to another element, there are no intervening elements present. Like numbers refer to like elements throughout. Furthermore, "coupled", "connected", "responsive", or variants thereof as used herein may include wirelessly coupled, connected, or responsive. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Well-known functions or constructions may not be described in detail for brevity and/or clarity. The term "and/or" includes any and all combinations of one or more of the associated listed items.

[0058] It will be understood that although the terms first, second, third, etc. may be used herein to describe various elements/operations, these elements/operations should not be limited by these terms. These terms are only used to distinguish one element/operation from another element/operation. Thus, a first element/operation in some embodiments could be termed a second element/operation in other embodiments without departing from the teachings of present inventive concepts. The same reference numerals or the same reference designators denote the same or similar elements throughout the specification.

[0059] As used herein, the terms "comprise", "comprising", "comprises", "include",

"including", "includes", "have", "has", "having", or variants thereof are open-ended, and include one or more stated features, integers, elements, steps, components or functions but does not preclude the presence or addition of one or more other features, integers, elements, steps, components, functions or groups thereof. Furthermore, as used herein, the common abbreviation "e.g.", which derives from the Latin phrase "exempli gratia," may be used to introduce or specify a general example or examples of a previously mentioned item, and is not intended to be limiting of such item. The common abbreviation "i.e.", which derives from the Latin phrase "id est," may be used to specify a particular item from a more general recitation.

[0060] Example embodiments are described herein with reference to block diagrams and/or flowchart illustrations of computer-implemented methods, apparatus (systems and/or devices) and/or computer program products. It is understood that a block of the block diagrams and/or flowchart illustrations, and combinations of blocks in the block diagrams and/or flowchart illustrations, can be implemented by computer program instructions that are performed by one or more computer circuits. These computer program instructions may be provided to a processor circuit of a general purpose computer circuit, special purpose computer circuit, and/or other programmable data processing circuit to produce a machine, such that the instructions, which execute via the processor of the computer and/or other programmable data processing apparatus, transform and control transistors, values stored in memory locations, and other hardware components within such circuitry to implement the functions/acts specified in the block diagrams and/or flowchart block or blocks, and thereby create means (functionality) and/or structure for implementing the functions/acts specified in the block diagrams and/or flowchart block(s).

[0061 ] These computer program instructions may also be stored in a tangible computer-readable medium that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable medium produce an article of manufacture including instructions which implement the functions/acts specified in the block diagrams and/or flowchart block or blocks.

[0062] A tangible, non-transitory computer-readable medium may include an electronic, magnetic, optical, electromagnetic, or semiconductor data storage system, apparatus, or device. More specific examples of the computer-readable medium would include the following: a portable computer diskette, a random access memory (RAM) circuit, a read-only memory (ROM) circuit, an erasable programmable read-only memory (EPROM or Flash memory) circuit, a portable compact disc read-only memory (CD-ROM), and a portable digital video disc read-only memory (DVD/BlueRay).

[0063] The computer program instructions may also be loaded onto a computer and/or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer and/or other programmable apparatus to produce a

computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions/acts specified in the block diagrams and/or flowchart block or blocks. Accordingly, embodiments of the present disclosure may be embodied in hardware and/or in software (including firmware, resident software, micro-code, etc.) that runs on a processor such as a digital signal processor, which may collectively be referred to as "circuitry," "a module" or variants thereof.

[0064] It should also be noted that in some alternate implementations, the

functions/acts noted in the blocks may occur out of the order noted in the flowcharts. For example, two blocks shown in succession may in fact be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, depending upon the

functionality/acts involved. Moreover, the functionality of a given block of the flowcharts and/or block diagrams may be separated into multiple blocks and/or the functionality of two or more blocks of the flowcharts and/or block diagrams may be at least partially integrated. Finally, other blocks may be added/inserted between the blocks that are illustrated. Moreover, although some of the diagrams include arrows on communication paths to show a primary direction of communication, it is to be understood that communication may occur in the opposite direction to the depicted arrows.

[0065] Many different embodiments have been disclosed herein, in connection with the above description and the drawings. It will be understood that it would be unduly repetitious and obfuscating to literally describe and illustrate every combination and subcombination of these embodiments. Accordingly, the present specification, including the drawings, shall be construed to constitute a complete written description of various example combinations and subcombinations of embodiments and of the manner and process of making and using them, and shall support claims to any such combination or subcombination.

[0066] Many variations and modifications can be made to the embodiments without substantially departing from the principles of the present inventive concepts. All such variations and modifications are intended to be included herein within the scope of present inventive concepts. Accordingly, the above disclosed subject matter is to be considered illustrative, and not restrictive, and the examples of embodiments are intended to cover all such modifications, enhancements, and other embodiments, which fall within the spirit and scope of present inventive concepts. Thus, to the maximum extent allowed by law, the scope of present inventive concepts is to be determined by the broadest permissible interpretation of the present disclosure including the examples of embodiments and their equivalents, and shall not be restricted or limited by the foregoing detailed description.

LISTING OF EMBODIMENTS:

Embodiment 1. A method of operating a network node to provide dual connectivity in a new radio telecommunications system, the method comprising:

allocating (700) two tunnel endpoint identifiers, TEIDs;

sending (702) the allocated TEIDs to at least other network node for transporting a Protocol Data Unit, PDU, session that can be split; and

receiving (704) two TEIDs for a master node and a secondary node.

Embodiment 2. The method of Embodiment 1, wherein the network node comprises a User Plane Function, UPF.

Embodiment 3. The method of any of Embodiments 1 to 2, further comprising: responsive to determining that the allocated TEIDs have not been used for transport of a split PSU session, releasing one of the two TEIDs for use for transporting another PDU session.

Embodiment 4. The method of any of Embodiments 1 to 3, wherein:

the allocated TEIDs comprise GTP-U TEIDs; and

the allocated TEIDs are sent to a master node.

Embodiment 5. The method of Embodiment 4, wherein the master node is a Master NG-RAN node.

Embodiment 6. A computer program product comprising a non- transitory computer readable medium storing program code that when executed by a processor of the network node causes the network node to perform operations of the method of any of Embodiments 1-5.

Embodiment 7. A network node adapted to perform the method of any of

Embodiments 1-5.

Embodiment 8. A network node for providing dual connectivity in a new radio telecommunications system, the network node configured to:

allocate two tunnel endpoint identifiers, TEIDs; send the allocated TEIDs to at least other network node for transporting a PDU session that can be split; and

receive two TEIDs for a master node and a secondary node.

Embodiment 9. The network node of Embodiment 8 further configured to perform the method of any of Embodiments 2-5.

Embodiment 10. A method of operating a master node to provide dual connectivity, the method comprising:

sending (800) a secondary node addition request message to as secondary node, SN; sending (802) a SN add/modify completion indication to the SN that informs the SN of that the operations to add/modify are complete.

Embodiment 11. The method of Embodiment 10, wherein the SN add/modify completion indication informs the SN that a Master Cell Group resource addition is complete.

Embodiment 12. The method of Embodiment 11, wherein the SN add/modify completion indication informs the SN of a transport layer address associated with the Master Cell Group resource that was added.

Embodiment 13. The method of any of Embodiments 10 to 12, wherein the SN add/modify completion indication is a S-NODE ADDMODIFY COMPLETE message.

Embodiment 14. The method of Embodiment 13, wherein the S-NODE

ADDMODIFY COMPLETE message contains a Xn-U GTP-U tunnel endpoint information to complete Xn-U tunnel establishment for Data Radio Bearers for which New Radio Packet Data Convergence Protocol is hosted by the secondary node.

Embodiment 15. The method of any of Embodiments 10 to 14, wherein the secondary node is a Secondary NG-RAN node.

Embodiment 16. A computer program product comprising a non-transitory computer readable medium storing program code that when executed by a processor of the master node causes the master node to perform operations of the method of any of Embodiments 10-15. Embodiment 17. A master node adapted to perform the method of any of Embodiments

10-15.

Embodiment 18. A master node to provide dual connectivity, the master node configured to:

send a secondary node addition request message to a secondary node, SN;

send a SN add/modify completion indication to the SN that informs the SN of that the operations to add/modify are complete.

Embodiment 19. The master node of Embodiment 18 further configured to perform the method of any of Embodiments 11-15.