Cell-specific management triggered tracing and minimization of drive tests from ran user plane functions

Abstract

Disclosed is an apparatus configured to receive, at a gNB-CU-User Plane (gNB-CUUP) node (110), a configuration request to activate management-triggered tracing. The configuration request comprising at least one New Radio – Cell Global Identifier (NR-CGI) corresponding to at least one cell within a network. The apparatus is also configured to receive, from a gNB-CU-Control Plane (gNB-CUCP) node (108), a bearer context setup request to activate one or more data bearers for a plurality of User Equipment (UEs) (102) associated with one or more cells. The bearer context setup request comprises another NR-CGI corresponding to each of the one or more cells. The apparatus also configured to activate, at the gNB-CUUP node (110), the management triggered tracing for at least one cell based on the at least one NR-CGI included in the configuration request and the one or more another NR-CGIs included in the bearer context setup request.

Description

CELL-SPECIFIC MANAGEMENT TRIGGERED TRACING AND MINIMIZATION OFDRIVE TESTS FROM RAN USER PLANE FUNCTIONSCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to India Non-Provisional Application No. 202411083273, filed on October 30, 2024, the entire contents of which are incorporated herein by reference.FIELD

[0002] The present disclosure relates to cell-specific management triggered tracing and Minimization of Drive Tests (MDT) from Radio Access Network (RAN) user plane functions.BACKGROUND

[0003] The information disclosed in this background section is only for the enhancement of understanding of the general background of the disclosure and should not be taken as an acknowledgment or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

[0004] 3rdGeneration Partnership Project’s (3GPP's) current management-based trace job and Minimization of Drive Tests (MDT) provisioning enable network operators to efficiently manage and customize tracing capabilities at a granular level, specifically at the per-cell level for various Radio Access Network (RAN) Network Functions (NFs). This allows operators to selectively enable tracing based on the distinct requirements of different cells, which facilitates targetedtroubleshooting, performance analysis, and network optimization without the need for extensive physical drive tests. By leveraging this capability, operators can enhance their operational efficiency, respond promptly to performance issues, and improve overall service quality for users while minimizing disruption to network operations.

[0005] In Next Generation - RAN (NG-RAN), after the Cell Traffic Trace has been activated in monitored cell(s), an NG-RAN node shall start a Trace Recording Session (TRS) for new call(s) / session(s) and for already existing call(s) / session(s) (events for existing call(s) / session(s) are not required to be recorded prior to the activation of the cell traffic trace). When the NG-RAN node starts a TRS, the NG-RAN node shall allocate a Trace Recording Session Reference (TRSR) for the given call or session. For file-based trace reporting, the NG-RAN node shall send the allocated TRSR, the trace reference, and a Trace Collection Entity (TCE) address in the CELL TRAFFIC TRACE message to an Access and Mobility Management Function (AMF) via an NG connection. For streaming trace reporting, the NG-RAN node shall send the allocated TRSR, the trace reference, and a Uniform Resource Identifier (URI) of a trace reporting Management Service (MnS) consumer in the CELL TRAFFIC TRACE message to the AMF via the NG connection.SUMMARY

[0006] This summary is provided to introduce a selection of concepts, in a simplified format, that are further described in the detailed description of the disclosure. This summary is neither intended to identify key or essential inventive concepts of the disclosure nor is it intended to determine the scope of the disclosure.

[0007] Disclosed herein is an apparatus. The apparatus is configured to receive, at a gNodeB- Centralized Unit-User Plane (gNB-CUUP) node, a configuration request to activate management- triggered tracing. The configuration request includes at least one New Radio - Cell Global Identifier (NR-CGI) corresponding to at least one cell within a network. The apparatus is also configured to receive, from a gNB-CU-Control Plane (gNB-CUCP) node, a bearer context setup request to activate one or more data bearers for a plurality of User Equipment (UEs) associated with one or more cells. The bearer context setup request comprises another NR-CGI corresponding to each of the one or more cells. The apparatus is further configured to activate, at the gNB-CUUP node, the management triggered tracing for at least one cell based on the at least one NR-CGI included in the configuration request and the one or more another NR-CGIs included in the bearer context setup request.

[0008] Disclosed herein is a method. The method includes receiving, by a gNodeB-Centralized Unit-User Plane (gNB-CUUP) node, a configuration request to activate management-triggered tracing. The configuration request includes at least one New Radio - Cell Global Identifier (NR- CGI) corresponding to at least one cell within a network. The method also includes receiving, from a gNB-CU-Control Plane (gNB-CUCP) node, a bearer context setup request to activate one or more data bearers for a plurality of User Equipment (UEs) associated with one or more cells. The bearer context setup request comprises another NR-CGI corresponding to each of the one or more cells. The method further includes activating, at the gNB-CUUP node, the management triggered tracing for at least one cell based on the at least one NR-CGI included in the configuration request and the one or more another NR-CGIs included in the bearer context setup request.

[0009] Disclosed herein is a non-transitory computer-readable medium storing instructions. The instructions comprise one or more instructions that are executed by a gNodeB-Centralized Unit-User Plane (gNB-CUUP) node. The gNB-CUUP node includes one or more processors. The instructions cause the one or more processors to receive a configuration request to activate management-triggered tracing. The configuration request includes at least one New Radio - Cell Global Identifier (NR-CGI) corresponding to at least one cell within a network. The instructions cause the one or more processors to receive, from a gNB-CU-Control Plane (gNB-CUCP) node, a bearer context setup request to activate one or more data bearers for a plurality of User Equipment (UEs) associated with one or more cells. The bearer context setup request comprises another NR- CGI corresponding to each of the one or more cells. The instructions cause the one or more processors to activate, at the gNB-CUUP node, the management triggered tracing for at least one cell based on the at least one NR-CGI included in the configuration request and the one or more another NR-CGIs included in the bearer context setup request.

[0010] To further clarify the advantages and features of the present disclosure, a more particular description of the disclosure will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawing. It is appreciated that these drawings depict only typical embodiments of the disclosure and are therefore not to be considered limiting its scope. The disclosure will be described and explained with additional specificity and detail with the accompanying drawings.BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Features, aspects, and advantages of embodiments of the disclosure will be described below with reference to the accompanying drawings, in which like reference numerals denote like elements, and wherein:FIG. 1 illustrates a network environment to implement cell-specific management triggered tracing and Minimization of Drive Tests (MDT) provisioning, in accordance with an embodiment of the present disclosure;FIGS. 2A-2B illustrate a sequence flow diagram corresponding to a method for performing the cell-specific management triggered tracing and MDT provisioning, in accordance with an embodiment of the present disclosure;FIG. 3 illustrates a flowchart depicting a method for performing the cell-specific management triggered tracing and MDT provisioning, in accordance with an embodiment of the present disclosure; andFIG. 4 is a diagram of example components of a wireless communication device, in accordance with an embodiment of the present disclosure.DETAILED DESCRIPTION

[0012] The following detailed description of example embodiments refers to the accompanying drawings. The present disclosure provides illustrations and descriptions, but is not intended to be exhaustive or to limit the implementations to the precise form disclosed. Modifications and variations are possible in light of the present disclosure or may be acquired from the practice of the implementations. Further, one or more features or components of one embodiment may be incorporated into or combined with another embodiment (or one or more features of anotherembodiment). Additionally, the flowchart and description of operations provided below relate to at least one of the embodiments in the present disclosure. It should be noted that it is possible to make other embodiments that do not exactly match the flowchart and its description. It is understood that in other embodiments one or more operations may be omitted, one or more operations may be added, and one or more operations may be performed simultaneously (at least in part).

[0013] It will be apparent that systems and / or methods, described herein, may be implemented in different forms of hardware, software, or a combination of hardware and software. The actual specialized control hardware or software code used to implement these systems and / or methods should not limit their implementations. Thus, the operation and behavior of the systems and / or methods are described herein without reference to specific software code. It is understood that software and hardware may be designed to implement the systems and / or methods based on the description herein.

[0014] Even though particular combinations of features are recited in the claims and / or disclosed in the specification, the particular combinations are not intended to limit the disclosure of implementations. In fact, many of these features may be combined in ways not specifically recited in the claims and / or disclosed in the specification. Even if a dependent claim directly depends on only one claim, the present disclosure may indicate that the dependent claim is dependent on other claims in the claim set.

[0015] No element, act, or instruction used herein should be construed as critical or essential unless explicitly described as such. Also, as used herein, the articles “a” and “an” (in other words, nouns not mentioned in the plural) are intended to include one or more items, and may be usedinterchangeably with “one or more.” Also, as used herein, the terms “has,” “have,” “having,” “include,” “including,” or the like are intended to be open-ended terms. Further, the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise. Furthermore, expressions such as “at least one of [A] and [B],” “[A] and / or [B],” or “at least one of [A] or [B]” are to be understood as including only A, only B, or both A and B.

[0016] The terms “mobile device”, “user device”, “User Equipment”, and “UE” may be used interchangeably throughout the description.

[0017] The terms “gNB-CUUP node” and “gNB-CUUP” are used interchangeably throughout the description.

[0018] The terms “gNB-CUCP node” and “gNB-CUCP” are used interchangeably throughout the description.

[0019] In 3rdGeneration Partnership Projects (3GPP’s) current management based tracing and Minimization of Drive Tests (MDT) provisioning, traces are to be enabled at per cell level for different Radio Access Network (RAN) Network Functions (NFs) (e.g., a gNodeB-Centralized Unit Control Plane (gNB-CUCP), a gNB-Distributed Unit (gNB-DU) and a gNB-CU User Plane (gNB-CUUP)). Furthermore, when the management-based tracing and MDT jobs are enabled / provisioned, messages related to all the User Equipment (UEs) in the cell are traced and corresponding trace records are sent to a Trace Collection Entity (TCE). However, currently, the gNB-CUUP does not have any means to know which set of UEs (i.e., call sessions) belong to the cell. In general, a cell may be identified by a corresponding New Radio - Cell Global Identifier (NR-CGI). However, the gNB-CUCP does not share NRCGIs for bearers created in the gNB-CUUP and hence the conventional solutions fail to perform cell-level trace activation and reportingfor gNB-CUUP related events / measurements. Thus, an activation and reporting of the gNB-CUUP related MDT events at the cell level is not supported in the RAN.

[0020] On the contrary, in view of the above limitation, the gNB-CUUP is forced to activate management-based traces for all UEs across all cells served by that gNB-CUUP. This results in a large number of MDT and trace events messaging flow towards the TCE, leading to a wastage of network resources and time.

[0021] The present disclosure enables the sharing of an Information Element (IE) including NG- CGIs from the gNB-CUCP to the gNB-CUUP for bearers created in the gNB-CUUP. This enables cell-level trace activation and reporting for the gNB-CUUP related bearers, events, and / or measurements. By activating the gNB-CUUP related traces and / or events at the cell level, the present disclosure enables limiting the messages to the UEs belonging to the corresponding cell only as identified by the NR-CGI.

[0022] FIG. 1 illustrates a network environment 100 to implement cell-specific management triggered tracing and MDT provisioning, in accordance with an embodiment of the present disclosure. The network environment 100 illustrates a UE 102, a gNodeB (gNB) 104, an Access and Mobility Management Function (AMF) 112, a Service Management and Orchestration (SMO) 114, and a TCE server 116. In one or more embodiments, the UE 102 may refer to mobile devices such as smartphones, tablets, and laptops that connect to a 5G network. The UE 102 may be communicably coupled with the gNB 104 through various communication interfaces, for transmitting data between the UE 102 and the gNB 104. The connection between the UE 102 and the gNB 104 enables the UE 102 to send uplink transmissions and receive downlink transmissions, facilitating overall connectivity and communication within the network environment 100.

[0023] The gNB 104 may be implemented in a disaggregated architecture. The disaggregated architecture is defined in 3GPP decomposing the gNB 104 into multiple logical entities. The multiple logical entities may include one or more first units may be represented by at least one distributed unit (gNB-DU) 106 and the one or more second units may be represented by a centralized unit (gNB-CU). The gNB-CU may be further split into a CU Control Plane (CP) part, also referred to as a gNB-CUCP 108, and a CU User Plane (UP) part, also referred to as a gNB- CUUP 110. Such a split enables the implementation of the CU-CP and CU-UP parts in different locations. For example, such a split of the gNB 104 into the plurality of logical entities enables flexibility, scalability, and efficiency in the deployment and operation of 5G networks. The disaggregated architecture of the gNB 104 may also include a Radio Unit (gNB-RU), not shown in FIG. 1. The gNB-RU may be responsible for the radio transmission and reception of signals. The gNB-RU may include physical Radio Frequency (RF) components such as antennas, power amplifiers, and analog-to-digital converters. The gNB-RU may be located at a cell site or a radio tower, close to the antennas. Further, the gNB-DU may perform baseband processing functions such as physical layer processing, channel coding, and modulation / demodulation. Particularly, the gNB-DU may host a Radio Link Control (RLC), a Medium Access Control (MAC) layer, and a Physical (PHY) layer. The gNB-DU may also perform scheduling operations. Multiple gNB-RUs may be connected to a single gNB-DU, allowing for centralized processing of multiple radio units. The gNB-CU may be responsible for higher-layer processing functions such as radio resource management, mobility management, and connection management. The gNB-CU may provide a centralized control point for multiple gNB-DUs, enabling network-wide coordination and optimization.

[0024] According to one configuration, the gNB-DU 106 may host multiple cells (for example, a max of 512 as per current specifications). The gNB-CUCP 108 may host the one or more gNB- DUs 106 and the one or more gNB-CUUPs 110. Also, the gNB-CUUP 110 may host the Packet Data Convergence Protocol-User Plane part (PDCP-U) and Service Data Adaptation Protocols (SDAP). More specifically, 3GPP RAN3 cardinality for the 5G gNB 104 defines that the gNB 104 may only include one gNB-CUCP. There may be an “n” number of gNB-DUs controlled by the gNB-CUCP 108. Further, there may be ‘m” number of gNB-CUUPs controlled by the gNB-CUCP 108 in the gNB 104. Also, one gNB-DU may be served by the multiple gNB-CUUP 110. The various entities and / or network functions within the gNB 104 may communicate via one or more interfaces including an Fl-C interface, an Fl-U interface, and an El interface. The Fl-C, Fl-U, and El interfaces The Fl-C interface is a control plane interface between the gNB-CU and the gNB-DU within the gNB 104. The Fl-C interface is used for signaling and control messages related to radio resource management, mobility management, and configuration management. The Fl-C interface facilitates coordination between the gNB-CU and the gNB-DU for efficient network operation and service delivery. The Fl-U interface is a user plane interface between the gNB-CU and the gNB-DU in the gNB 104 architecture. The Fl-U is responsible for transporting user data packets between the gNB-CU and the gNB-DU. The Fl-U interface handles user plane data processing, including packet forwarding, Quality of Service (QoS) management, and encryption / decry ption functions. The El interface in the gNB 104 connects the entity with the gNB-CU and / or the gNB 104 to core network elements, such as the AMF 112.

[0025] The AMF 112 may be configured to perform procedures such as connection management, registration, and mobility support, for the UE 102. The AMF 112 may be responsible forauthenticating and authorizing the UE 102. The AMF 112 may also be configured to handle registration procedures for the UE 102. The registration procedures may include registration, deregistration, and re-registration processes when the UE 102 moves between different network areas within the network environment 100. The AMF 112 may also perform various other network functions as required by the UE 102 to effectively access and roam within the network environment 100.

[0026] The network environment 100 further includes the SMO 114. The SMO 114 may facilitate the management, orchestration, and optimization of RANs. The SMO 114 may enable operators to effectively manage multi-vendor RAN deployments and implement flexible, automated network operations, significantly enhancing efficiency and service delivery. In one or more embodiments, the SMO 114 may be configured to orchestrate resources across the RAN, including the configuration, management, and coordination of various elements of the gNB 104. The SMO 114 may be configured to maintain service assurance and quality. In one or more embodiments, the SMO 114 may be configured to define and enforce policies related to network behavior and / or resource management.

[0027] The gNB 104 may also be connected to the TCE server 116 (also referred to as the TCE 116). The TCE 116 may be configured to collect, process, and manage the trace data for performance analysis, troubleshooting, and optimization of network operations. The TCE 116 may collect the trace data from various sources in the RAN, for example, from the gNB-CUUP 110, which facilitates data transmission for active mobile users. The TCE 116 is configured to reduce the need for traditional drive tests, which are resource-intensive and time-consuming. Byleveraging real-time data and trace information, operators can obtain insights about network performance without the need for physical drive tests.

[0028] FIGS. 2A-2B illustrate a sequence flow diagram corresponding to a method 200 for performing the cell-specific management triggered tracing and MDT provisioning, in accordance with an embodiment of the present disclosure. The sequence flow diagram may illustrate a sequence of operations between the one or more UEs 102 (hereinafter referred to as the UE 102), the gNB-DU 106, the gNB-CUCP 108, the gNB-CUUP 110, the AMF 112, the SMO 114, and the TCE 116.

[0029] Referring to FIG. 2A, at operation 202, the SMO 114 may transmit a configuration request to the gNB-CUUP 110. The configuration request may correspond to the cell-specific management triggered tracing and MDT provisioning. In one or more embodiments, the configuration request may include parameters such as, but not limited to, a number of trace jobs, a type of trace jobs, a trace depth, and a trace target ID (NR-CGI). The number of trace jobs may refer to a total number of specific tracing tasks or operations to be performed by the gNB-CUUP 110. The type of trace jobs may define a trace job category based on an intended object or a method of execution. For example, the type of trace jobs may correspond to, but are not limited to, a performance-based trace, an event-based trace, and an error-based trace. In one or more embodiments, the type of trace may indicate the requested trace jobs are to be performed at the NG-RAN cell level. The trace depth may define whether the whole signalling message should be recorded or just some IES need to be recorded from the messages. The trace target ID may indicate a specific entity or an aspect of the network that is under observation for the trace job. For example, the trace target ID may include a STRING (including one or more characters) value and include the NR-CGI. The NR-CGI may correspond to a specific cell for which tracing and reporting is requested or has been activated. In one or more embodiments, the configuration request may indicate the trace and MDT jobs to be performed for the cell identified using the NR.-CGI. The NR.-CGI may be defined as a part of an initial configuration or a dynamic configuration. In the case of the dynamic configuration, the NR-CGI may be updated based on the requirement at the time of the configuration request.

[0030] At operation 204, the gNB-CUUP 110 may process the received trace and MDT jobs based on the one or more parameters included in the configuration request. In one or more embodiments, the gNB-CUUP 110 may identify the trace and MDT jobs based on the trace target (identified based on the corresponding ID) and the NR.-CGI included in the configuration request. In one or more embodiments, the gNB-CUUP 110 may activate the trace and MDT jobs at the NR-CGI level based on the received configuration request.

[0031] At operation 206, the gNB-CUUP 110 may transmit a gNB-CUUP configuration response to the SMO 114. The gNB-CUUP configuration response may indicate an acknowledgment of the configuration request transmitted at the operation 202. Further, the gNB-CUUP configuration response may indicate that the gNB-CUUP 110 has activated the trace and MDT jobs at the NR- CGI level.

[0032] At operation 208, the UE 102 may initiate a Radio Resource Control (RRC) setup complete procedure with a Non-Access Stratum (NAS) registration request. The UE 102 may initiate the RRC setup complete procedure to register with the 5G core network. The NAS registration request may include information, such as, but not limited to, a device identity of the UE 102, subscription information associated with the UE 102, a location of the UE 102, security information associated with the UE 102, and so forth. In one or more embodiments, the UE 102 may perform the RRCsetup complete procedure utilizing the gNB-CUCP 108. In one or more embodiments, the UE 102 may trigger the registration or service request procedure towards the AMF 112 after completing the RRC setup procedure with the RAN (i.e., the gNB-CUCP 108) by carrying the NAS Registration Request or the service request as a payload of a RRC setup complete message.

[0033] In response to the triggered RRC setup complete procedure, the RAN (i.e., the gNB-CUCP 108) may transmit a Next Generation Application Protocol (NGAP) initial UE message to the AMF 112, as shown by operation 210. The gNB 104 and / or the associated entities (for example, the gNB-DU 106, the gNB-CUCP 108, and the gNB-CUUP 110) may communicate with the 5GC and / or the associated entities (for example, the AMF 112) via an NG interface. In one or more embodiments, the gNB-CUCP 108 may initiate an NGAP initial UE message producer when the gNB-CUCP 108 receives a first uplink NAS message from the UE 102 to be forwarded to the AMF 112. In an embodiment, the structure of the NGAP initial UE message may include, but not be limited to, a group name, a presence indication, a range, an IE type and reference, semantic description, and associated criticality information.

[0034] In response to the NGAP initial UE message, the AMF 112 may respond to the gNB-CUCP 108 with an NGAP initial context setup request, as shown by operation 212. In one or more embodiments, the NGAP initial context setup request may include a Protocol Data Unit (PDU) session setup configuration. In another embodiment, the NGAP initial context setup request may also include information such as, but not limited to, a security key, a mobility restriction list, UE radio capability, and UE security capabilities. The NGAP initial context setup request may correspond to a message used in the 5G network to establish initial user plane and control plane contexts for the UE 102 at the gNB 104. The AMF 112 may transmit the NGAP initial contextsetup request to initialize an overall context of the UE 102 when it connects to the NG-RAN (NextGeneration Radio Access Network) node (for example, the gNB-CUCP 108, the gNB-CUUP 110).For example, the AMF 112 acting as a Mobility Management Entity (MME) transmits the NGAP initial context setup request to request the setup of the UE context. The NGAP initial context setup request message and / or the PDU session setup configuration may indicate network slices required for the UE 102. The PDU session setup configuration may include information required for creating and managing user data sessions that transport user data within the network environment 100.

[0035] At operation 214, the gNB-CUCP 108 may transmit an El AP bearer context setup request to the gNB-CUUP 110. The El AP bearer context setup request may correspond to a message that sets up the El bearer context, which is part of the El Application Protocol (El AP), for the UE 102. In one or more embodiments, the gNB-CUCP 108 may include an NR-CGI IE within the E1AP bearer context setup request. The NR-CGI IE may include an NR-CGI corresponding to a proposed cell to create the bearer context for the UE 102 at the gNB-CUUP 110. In one or more embodiments, the E1AP bearer context setup request may be used to initiate an establishment of the bearer context for user data transmission within the network environment 100. The E1AP bearer context setup request may include information related to the configuration of bearer parameters, such as, but not limited to, Quality of Service (QoS) flows, resource allocations, and any necessary forwarding instructions for the UE 102. The El AP bearer context setup request may ensure that the established bearer meets required service quality and delivery standards.

[0036] The gNB-CUUP 110 may process the received E1AP bearer context setup request and create the bearer context for the UE 102. At operation 216, the gNB-CUUP 110 may activate theone or more traces and MDT jobs for the bearer contexts for which the configured NR-CGI (i.e., the NR-CGI included in the configuration request) matches with the received NG-CGI IE in theE1AP bearer context setup request. For example, the gNB-CUUP 110 may use the newly proposed NR- CGI IE in the El AP bearer context setup message to identify whether the created bearer needs to be a part of tracing based on the configuration request received at operation 202. If the NR-CGI matches with the configured cell ID (i.e., the NR-CGI included in the configuration request) for the trace target in the trace job, the gNB-CUUP 110 may activate the traces and MDT jobs for that UE 102 periodically or in an event-based condition. Thus, the gNB-CUUP 110 may effectively and effectively perform the tracing and the MDT provisioning for the UEs corresponding to the configured NR-CGI. Thereby, the gNB-CUUP 110 saves network resources and improves the overall performance of the gNB 104 and / or the network.

[0037] At operation 218, the gNB-CUUP 110 may transmit an E1AP bearer context setup response to the gNB-CUCP 108. The E1AP bearer context setup response may indicate the creation of the bearer context for the UE 102 as requested in the El AP bearer context setup request. For the NG-RAN, in the E1AP bearer context setup response, the gNB-CUUP 110 may report various information related to the PDU sessions, to the gNB-CUCP 108. Such information may include, but is not limited to, a list of PDU sessions that are successfully established, a list of PDU sessions that failed to be established, a list of Data Resource Bearers (DRBs) that are successfully established, a list of DRBs which failed to be established, a list of QoS flows which are successfully established, and a list of QoS flows which failed to be established. In one or more embodiments, the gNB-CUUP 110 may also indicate a reason for the failure of establishment of the PDU session, the DRBs, and / or the QoS flows in the El AP bearer context setup response.

[0038] Referring to FIG. 2B, at operation 220, the gNB-CUCP 108 may transmit an initial context setup response to the AMF 112. In one or more embodiments, the gNB-CUCP 108 may generate the NGAP initial context setup response based on the E1AP bearer context setup response as received from the gNB-CUUP 110. For example, the NGAP initial context setup response may indicate a successful / failed outcome of the NGAP initial context setup request from the AMF 112.

[0039] At operation 222, the UE registration procedure may be complete. The UE 102 registration procedure complete may indicate the activation of the cell traffic trace at the gNB-CUCP 108 and / or the gNB-CUUP 110. In an end note, a UE registration procedure complete indication may indicate to send cell traffic trace as soon as tracing is started for the bearer context belonging to the cell identified by the corresponding NR-CGI. Further, the gNB-CUUP 110 may send trace data periodically or based on events to the TCE 116.

[0040] In one or more embodiments, as the gNB-CUUP 110 activates the traces only for the bearers belonging to the specific cell, the gNB-CUUP 110 may send a CELL TRAFFIC TRACE message to gNB-CUCP 108 for each bearer for which the trace is activated.

[0041] Furthermore, at operation 224, the gNB-CUUP 110 may transmit gNB-CUUP trace data to the TCE server 116. The gNB-CUUP trace data may include reports corresponding to the tracing and the MDT events detected based on MDT jobs. In one or more embodiments, the gNB-CUUP 110 may transmit the gNB-CUUP trace data via one of a file-based method or a streaming method. The file-based method requires a file to be generated for all the traces and MDT traces collected over a period of time and the generated file is transmitted to the TCE 116. In the streaming method, the gNB-CUUP 110 may transmit the gNB-CUUP trace data in a continuous stream.

[0042] Since the trace and MDT jobs are activated only for the specific NRCGI-related UEs, the method 200 reduces the number of traces and MDT events reports to the TCE server 116. This reduces bandwidth consumption between the gNB-CUUP 110 and the TCE server 116.

[0043] In one or more embodiments, similar to the method 200, an NR-CGI IE may be included in an E1AP bearer context modification request to inform the gNB-CUUP 110 about any change in cell IDs during UE handovers.

[0044] In one or more embodiments, the method 200 may be implemented to an eNodeB (eNB) UP as well if the eNB is split into control plane and user plane entities using an El interface. In the case of eNB UP, the IE shared indicates the cell may be ECGI (EUTRA CGI) instead of NR CGI.

[0045] FIG. 3 illustrates a flowchart depicting a method 300 for performing the cell-specific management triggered tracing and MDT provisioning, in accordance with an embodiment of the present disclosure. The method 300 may be performed by the gNB-CUUP node 110.

[0046] At step 302, the gNB-CUUP node 110 may receive a configuration request to activate management-triggered tracing. The configuration request may include at least one NR-CGI corresponding to at least one cell within the network. In one or more embodiments, in response to the receipt of the configuration request, the gNB-CUUP node 110 may identify one or more of a number of trace jobs, a type of trace request, a trace target, a cell type, and the at least one NR- CGI corresponding to the at least one cell, based on the received configuration request. The gNB- CUUP node 110 may receive the configuration request from a 5GCN entity (for example, the SMO 114, a Network Management System (NMS), and an Element Management System (EMS)). In one or more embodiments, the configuration request may include, but is not limited to, a numberof trace jobs, a target ID associated with a trace target, and a cell type. Furthermore, the gNB- CUUP node 110 may transmit a gNB-CUUP configuration response to the 5GCN entity. In one or more embodiments, the gNB-CUUP configuration response may indicate an acknowledgment of the configuration request.

[0047] At step 304, the gNB-CUUP node 110 may receive a bearer context setup request to activate one or more data bearers for the plurality of User Equipment (UEs) 102 associated with one or more cells. In one or more embodiments, the bearer context setup request may include another NR-CGI corresponding to each of the one or more cells.

[0048] At step 306, the gNB-CUUP node 110 may activate the management triggered tracing for at least one cell based on the at least one NR-CGI included in the configuration request and the one or more another NR-CGIs included in the bearer context setup request. In one or more embodiments, the gNB-CUUP node 110 may transmit one or more interface traces and one or more Minimization of Drive Tests (MDT) jobs to perform the management triggered tracing, to at least one gNB 104 associated with the gNB-CUUP node 110 and the plurality of UEs 102. In one or more embodiments, the gNB-CUUP node 110 may be configured to perform at least one of the one or more traces and the one or more MDT jobs to monitor one or more Key Performance Indicators (KPIs) associated with the at least one cell. The one or more KPIs may include, but are not limited to, a Reference Signal Received Power (RSRP), a Reference Signal Received Quality (RSRQ), a Signal-to-Interference-plus-Noise Ratio (SINR), power headroom measurements, received interference power measurements, data volume measurements, throughput measurements, packet delay measurements, packet loss rate measurements, a Received Signal Strength Indicator(RSSI), and a Round-Trip Time (RTT).

[0049] In one or more embodiments, the gNB-CUUP 110 may be configured to transmit a trace report corresponding to the management triggered tracing to the TCE 116. The trace report comprises the at least one of the one or more trace events and the or more MDT events.

[0050] While the above-discussed steps in FIG. 3 are shown and described in a particular sequence, the steps may occur in variations to the sequence in accordance with various embodiments. Further, a detailed description related to the various steps of FIG. 3 is already covered in the description related to FIGS. 1, 2A, and 2B, and is omitted herein for the sake of brevity.

[0051] FIG. 4 is a diagram of example components of a wireless communication device 400 (also referred to as the device / apparatus 400), in accordance with an embodiment of the present disclosure. In one or more embodiments, the wireless communication device 400 may correspond to the UE 102, the gNB-DU 106, the gNB-CUCP 108, the gNB-CUUP 110, the AMF 112, the SMO 114, and / or the TCE server 116. As shown in FIG. 4, the device 400 includes a processor 410, a memory 420, a storage component 430, an input component 440, an output component 450, a communication interface 460, and a bus 470.

[0052] The processor 410, as used herein, means any type of computational circuit that may comprise hardware elements and software elements. The processor 410 may be embodied as a multi-core processor, a single-core processor, or a combination of one or more multi-core processors and / or one or more single-core processors, a distributed processing system, or the like. The processor 410 may be a Central Processing Unit (CPU), a Graphics Processing Unit (GPU), an Accelerated Processing Unit (APU), an Application-Specific Integrated Circuit (ASIC), or another type of processing component.

[0053] The memory 420 includes a non-transitory computer-readable medium. The memory 420 includes a Random-Access Memory (RAM), a Read Only Memory (ROM), and / or another type of dynamic or static storage device (e.g., a flash memory, a magnetic memory, and / or an optical memory) that stores information and / or instructions for use by the processor 410. The memory 420 comprises machine-readable instructions which are executable by the processor 410. These machine-readable instructions when executed by the processor 410 cause the processor 410 to perform one or more method steps of an embodiment described above.

[0054] The storage component 430 stores information and / or software related to the operation and use of the device 400. For example, the storage component 430 may include a hard disk (e.g., a magnetic disk, an optical disk, a magneto-optic disk, and / or a solid-state disk), a Compact Disc (CD), a Digital Versatile Disc (DVD), a floppy disk, a cartridge, a magnetic tape, and / or another type of non-transitory computer-readable medium, along with a corresponding drive.

[0055] The input component 440 is configured to receive information, such as user input. For example, the input component 440 may include, but not be limited to, a touch screen display, a keyboard, a keypad, a mouse, a button, a switch, and / or a microphone. Additionally, or alternatively, the input component 440 may include a sensor for sensing information (e.g., a Global Positioning System (GPS), an accelerometer, a gyroscope, and / or an actuator).

[0056] The output component 450 is configured to provide output information from the device 400. For example, the output component 450 maybe, but is not limited to, a display, a speaker, an instruction device to an external device, and / or one or more Light-Emitting Diodes (LEDs).

[0057] The communication interface 460 is an interface that provides a communication connection to other devices, such as external devices and internal devices. The connection by thecommunication interface 460 can be a wired connection, a wireless connection, or a combination of wired and wireless connections, and can be a direct connection or an indirect connection via a communication network that exists between the device 400 and other devices. In other words, the standard of the communication interface 460 is not limited.

[0058] The bus 470 acts as an interconnect between the processor 410, the memory 420, the storage component 430, the input component 440, the output component 450, and the communication interface 460 of the device 400. The bus 470 may include a wired interconnection or a wireless interconnection.

[0059] The number and arrangement of components shown in FIG. 4 are provided as an example. In practice, the device 400 may include additional components, fewer components, different components, or differently arranged components than those shown in FIG. 4. Additionally, or alternatively, a set of components (e.g., one or more components) of the device 400 may perform one or more functions described as being performed by another set of components of the device 400. Further, one or more method steps described in any of the embodiments may be performed utilizing a plurality of devices 400 in communication with one another.

[0060] It is understood that terms including “unit” or “module” at the end may refer to the unit for processing at least one function or operation and may be implemented in hardware, software, or a combination of hardware and software.

[0061] Examples of the techniques and apparatus described herein include, but are not limited to, the following enumerated embodiments:[1] An apparatus configured to:receive, at a gNodeB-Centralized Unit-User Plane (gNB-CUUP) node, a configuration request to activate management-triggered tracing, the configuration request comprising at least one New Radio - Cell Global Identifier (NR-CGI) corresponding to at least one cell within a network; receive, from a gNB-CU-Control Plane (gNB-CUCP) node, a bearer context setup request to activate one or more data bearers for a plurality of User Equipment (UEs) associated with one or more cells, wherein the bearer context setup request comprises another NR-CGI corresponding to each of the one or more cells; and activate, at the gNB-CUUP node, the management triggered tracing for at least one cell based on the at least one NR-CGI included in the configuration request and the one or more another NR- CGIs included in the bearer context setup request.[2] The apparatus as described in [1], wherein in response to receipt of the configuration request, the apparatus is configured to: identify, based on the received configuration request, at least one of a number of trace jobs, a type of trace request, a trace target, a cell type, and the at least one NR-CGI corresponding to the at least one cell; and transmit a gNB-CUUP configuration response indicating an acknowledgement of the configuration request.[3] The apparatus as described in any one of [l]-[2], wherein to activate the management triggered tracing, the apparatus is configured to: transmit, to at least one of a gNB associated with the gNB-CUUP node and the plurality of UEs, one or more interface trace messages and one or more Minimization of Drive Tests (MDT) jobs to perform the management triggered tracing.[4] The apparatus as described in any one of [l]-[3], wherein to perform the management triggered tracing, the apparatus is configured to perform at least one of the one or more traces and the one or more MDT jobs to monitor one or more Key Performance Indicators (KPIs) associated with the at least one cell.[5] The apparatus as described in any one of

[0001] -[4], wherein the one or more KPIs comprise one or more of a Reference Signal Received Power (RSRP), a Reference Signal Received Quality (RSRQ), a Signal-to-Interference-plus-Noise Ratio (SINR), power headroom measurements, received interference power measurements, data volume measurements, throughput measurements, packet delay measurements, packet loss rate measurements, a Received Signal Strength Indicator (RSSI), and a Round-Trip Time (RTT).[6] The apparatus as described in any one of

[0001] -[5], further configured to: transmit, to a Trace Collection Entity (TCE) connected with the gNB-CUUP node, a trace report corresponding to the management triggered tracing, wherein the trace report comprises the at least one of the one or more trace messages and the one or more MDT traces.[7] The apparatus as described in any one of [l]-[6], wherein the configuration request further comprises at least one of a number of trace jobs, a target ID associated with a trace target, and a cell type.[8] The apparatus as described in any one of [l]-[7], wherein the apparatus is configured to receive the configuration request from one of a Service Management and Orchestration (SMO), a Network Management System (NMS), and an Element Management System (EMS).[9] A method comprising:receiving, by a gNodeB-Centralized Unit-User Plane (gNB-CUUP) node, a configuration request to activate management-triggered tracing, the configuration request comprising at least one New Radio - Cell Global Identifier (NR-CGI) corresponding to at least one cell within a network; receiving, from a gNB-CU-Control Plane (gNB-CUCP) node, a bearer context setup request to activate one or more data bearers for a plurality of User Equipment (UEs) associated with one or more cells, wherein the bearer context setup request comprises another NR-CGI corresponding to each of the one or more cells; and activating, at the gNB-CUUP node, the management triggered tracing for at least one cell based on the at least one NR-CGI included in the configuration request and the one or more another NR- CGIs included in the bearer context setup request.

[0010] The method as described in [9], wherein in response to receiving the configuration request, the method comprises: identify, based on the received configuration request, at least one of a number of trace jobs, a type of trace request, a trace target, a cell type, and the at least one NR-CGI corresponding to the at least one cell; and transmit, by the gNB-CUUP node, a gNB-CUUP configuration response indicating an acknowledgement of the configuration request.

[0011] The method as described in any one of [9]-

[0010] , wherein for activating the management triggered tracing, the method comprises: transmitting, to at least one of a gNB associated with the gNB-CUUP node and the plurality of UEs, one or more interface trace messages and one or more Minimization of Drive Tests (MDT) jobs to perform the management triggered tracing.

[0012] The method as described in any one of [9]-[l 1], wherein the management triggered tracing comprises performing at least one of one or more traces and the one or more MDT jobs to monitor one or more Key Performance Indicators (KPIs) associated with the at least one cell.

[0013] The method as described in any one of [9]-

[0012] , wherein the one or more KPIs comprises one or more of a Reference Signal Received Power (RSRP), a Reference Signal Received Quality (RSRQ), a Signal-to-Interference-plus-Noise Ratio (SINR), power headroom measurements, received interference power measurements, data volume measurements, throughput measurements, packet delay measurements, packet loss rate measurements, a Received Signal Strength Indicator (RSSI), and a Round-Trip Time (RTT).

[0014] The method as described in any one of [9]-

[0013] , further comprising: transmitting, by the gNB-CUUP node to a Trace Collection Entity (TCE), a trace report corresponding to the management triggered tracing, wherein the trace report comprises the at least one of the one or more trace messages and the or more MDT traces.

[0015] The method as described in any one of [9]-

[0014] , wherein the configuration request further comprises at least one of a number of trace jobs, a target ID associated with a trace target, and a cell type.

[0016] The method as described in any one of [9]-

[0015] , wherein the method comprises receiving the configuration request from one of a Service Management and Orchestration (SMO), a Network Management System (NMS), and an Element Management System (EMS).

[0017] A non-transitory computer-readable medium storing instructions, the instructions comprising: one or more instructions that, when executed by a gNodeB-Centralized Unit-UserPlane (gNB-CUUP) node, the gNB-CUUP node comprising one or more processors, cause the one or more processors to: receive a configuration request to activate management-triggered tracing, the configuration request comprising at least one New Radio - Cell Global Identifier (NR-CGI) corresponding to at least one cell within a network; receive, from a gNB-CU-Control Plane (gNB-CUCP) node, a bearer context setup request to activate one or more data bearers for a plurality of User Equipment (UEs) associated with one or more cells, wherein the bearer context setup request comprises another NR-CGI corresponding to each of the one or more cells; and activate, at the gNB-CUUP node, the management triggered tracing for at least one cell based on the at least one NR-CGI included in the configuration request and the one or more another NR- CGIs included in the bearer context setup request.

[0018] The non-transitory computer-readable medium as described in

[0017] , wherein in response to receipt of the configuration request, the instructions cause the one or more processors to: identify, based on the received configuration request, at least one of a number of trace jobs, a type of trace request, a trace target, a cell type, and the at least one NR-CGI corresponding to the at least one cell; and transmit a gNB-CUUP configuration response indicating an acknowledgement of the configuration request.

[0019] The non-transitory computer-readable medium as described in any one of

[0017] -

[0018] , wherein to activate the management triggered tracing, the instructions cause the one or more processors to:transmit, to at least one of a gNB associated with the gNB-CUUP node and the plurality of UEs, one or more interface trace messages and one or more Minimization of Drive Tests (MDT) jobs to perform the management triggered tracing.

[0020] The non-transitory computer-readable medium as described in any one of

[0017] -

[0019] , wherein to perform the management triggered tracing , the instructions cause the one or more processors to perform at least one of one or more traces and the one or more MDT jobs to monitor one or more KPIs associated with the at least one cell.

[0062] While specific language has been used to describe the disclosure, any limitations arising on account of the same are not intended. As would be apparent to a person in the art, various working modifications may be made to the method in order to implement the inventive concept as taught herein.

[0063] The drawings and the forgoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. For example, orders of processes described herein may be changed and are not limited to the manner described herein.

[0064] Moreover, the actions of any flow diagram need not be implemented in the order shown; nor do all of the acts necessarily need to be performed. Also, those acts that are not dependent on other acts may be performed in parallel with the other acts. The scope of embodiments is by no means limited by these specific examples. Numerous variations, whether explicitly given in thespecification or not, such as differences in structure, dimension, and use of material, are possible. The scope of embodiments is at least as broad as given by the following claims.

[0065] Benefits, other advantages, and solutions to problems have been described above with regard to specific embodiments. However, the benefits, advantages, solutions to problems, and any component(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential feature or component of any or all the claims.

[0066] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of at least one embodiment, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

Claims

WE CLAIM:

1. An apparatus configured to: receive, at a gNodeB-Centralized Unit-User Plane (gNB-CUUP) node, a configuration request to activate management-triggered tracing, the configuration request comprising at least one New Radio - Cell Global Identifier (NR-CGI) corresponding to at least one cell within a network; receive, from a gNB-CU-Control Plane (gNB-CUCP) node, a bearer context setup request to activate one or more data bearers for a plurality of User Equipment (UEs) associated with one or more cells, wherein the bearer context setup request comprises another NR-CGI corresponding to each of the one or more cells; and activate, at the gNB-CUUP node, the management triggered tracing for at least one cell based on the at least one NR-CGI included in the configuration request and the one or more another NR- CGIs included in the bearer context setup request.

2. The apparatus as claimed in claim 1, wherein in response to receipt of the configuration request, the apparatus is configured to: identify, based on the received configuration request, at least one of a number of trace jobs, a type of trace request, a trace target, a cell type, and the at least one NR-CGI corresponding to the at least one cell; and transmit a gNB-CUUP configuration response indicating an acknowledgement of the configuration request.

3. The apparatus as claimed in claim 1, wherein to activate the management triggered tracing, the apparatus is configured to: transmit, to at least one of a gNB associated with the gNB-CUUP node and the plurality of UEs, one or more interface trace messages and one or more Minimization of Drive Tests (MDT) jobs to perform the management triggered tracing.

4. The apparatus as claimed in claim 1, wherein to perform the management triggered tracing, the apparatus is configured to perform at least one of the one or more traces and the one or more MDT jobs to monitor one or more Key Performance Indicators (KPIs) associated with the at least one cell.

5. The apparatus as claimed in claim 4, wherein the one or more KPIs comprise one or more of a Reference Signal Received Power (RSRP), a Reference Signal Received Quality (RSRQ), a Signal-to-Interference-plus-Noise Ratio (SINR), power headroom measurements, received interference power measurements, data volume measurements, throughput measurements, packet delay measurements, packet loss rate measurements, a Received Signal Strength Indicator (RSSI), and a Round-Trip Time (RTT).

6. The apparatus as claimed in claim 4, further configured to: transmit, to a Trace Collection Entity (TCE) connected with the gNB-CUUP node, a trace report corresponding to the management triggered tracing, wherein the trace report comprises the at least one of the one or more trace messages and the one or more MDT traces.

7. The apparatus as claimed in claim 1, wherein the configuration request further comprises at least one of a number of trace jobs, a target ID associated with a trace target, and a cell type.

8. The apparatus as claimed in claim 1, wherein the apparatus is configured to receive the configuration request from one of a Service Management and Orchestration (SMO), a Network Management System (NMS), and an Element Management System (EMS).

9. A method comprising: receiving, by a gNodeB-Centralized Unit-User Plane (gNB-CUUP) node, a configuration request to activate management-triggered tracing, the configuration request comprising at least one New Radio - Cell Global Identifier (NR-CGI) corresponding to at least one cell within a network; receiving, from a gNB-CU-Control Plane (gNB-CUCP) node, a bearer context setup request to activate one or more data bearers for a plurality of User Equipment (UEs) associated with one or more cells, wherein the bearer context setup request comprises another NR-CGI corresponding to each of the one or more cells; and activating, at the gNB-CUUP node, the management triggered tracing for at least one cell based on the at least one NR-CGI included in the configuration request and the one or more another NR-CGIs included in the bearer context setup request.

10. The method as claimed in claim 9, wherein in response to receiving the configuration request, the method comprises:identifying, based on the received configuration request, at least one of a number of trace jobs, a type of trace request, a trace target, a cell type, and the at least one NR-CGI corresponding to the at least one cell; and transmitting, by the gNB-CUUP node, a gNB-CUUP configuration response indicating an acknowledgement of the configuration request.

11. The method as claimed in claim 9, wherein for activating the management triggered tracing, the method comprises: transmitting, to at least one of a gNB associated with the gNB-CUUP node and the plurality of UEs, one or more interface trace messages and one or more Minimization of Drive Tests (MDT) jobs to perform the management triggered tracing.

12. The method as claimed in claim 9, wherein the management triggered tracing comprises performing at least one of one or more traces and the one or more MDT jobs to monitor one or more Key Performance Indicators (KPIs) associated with the at least one cell.

13. The method as claimed in claim 12, wherein the one or more KPIs comprises one or more of a Reference Signal Received Power (RSRP), a Reference Signal Received Quality (RSRQ), a Signal-to-Interference-plus-Noise Ratio (SINR), power headroom measurements, received interference power measurements, data volume measurements, throughput measurements, packet delay measurements, packet loss rate measurements, a Received Signal Strength Indicator (RS SI), and a Round-Trip Time (RTT).

14. The method as claimed in claim 9, further comprising: transmitting, by the gNB-CUUP node to a Trace Collection Entity (TCE), a trace report corresponding to the management triggered tracing, wherein the trace report comprises the at least one of the one or more trace messages and the one or more MDT traces.

15. The method as claimed in claim 9, wherein the configuration request further comprises at least one of a number of trace jobs, a target ID associated with a trace target, and a cell type.

16. The method as claimed in claim 9, wherein the method comprises receiving the configuration request from one of a Service Management and Orchestration (SMO), a Network Management System (NMS), and an Element Management System (EMS).

17. A non-transitory computer-readable medium storing instructions, the instructions comprising: one or more instructions that, when executed by a gNodeB-Centralized Unit-User Plane (gNB- CUUP) node, the gNB-CUUP node comprising one or more processors, cause the one or more processors to: receive a configuration request to activate management-triggered tracing, the configuration request comprising at least one New Radio - Cell Global Identifier (NR-CGI) corresponding to at least one cell within a network; receive, from a gNB-CU-Control Plane (gNB-CUCP) node, a bearer context setup request to activate one or more data bearers for a plurality of User Equipment (UEs) associated with one ormore cells, wherein the bearer context setup request comprises another NR-CGI corresponding to each of the one or more cells; and activate, at the gNB-CUUP node, the management triggered tracing for at least one cell based on the at least one NR-CGI included in the configuration request and the one or more another NR- CGIs included in the bearer context setup request.

18. The non-transitory computer-readable medium as claimed in claim 17, wherein in response to receipt of the configuration request, the instructions cause the one or more processors to: identify, based on the received configuration request, at least one of a number of trace jobs, a type of trace request, a trace target, a cell type, and the at least one NR-CGI corresponding to the at least one cell; and transmit a gNB-CUUP configuration response indicating an acknowledgement of the configuration request.

19. The non-transitory computer-readable medium as claimed in claim 17, wherein to activate the management triggered tracing, the instructions cause the one or more processors to: transmit, to at least one of a gNB associated with the gNB-CUUP node and the plurality of UEs, one or more interface trace messages and one or more Minimization of Drive Tests (MDT) jobs to perform the management triggered tracing.

20. The non-transitory computer-readable medium as claimed in claim 17, wherein to perform the management triggered tracing, the instructions cause the one or more processors to perform at leastone of one or more traces and the one or more MDT jobs to monitor one or more KPIs associated with the at least one cell.

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