Apparatus and method for providing synchronization information of first communication network to second communication network in communication system

A method of a user equipment (UE) in a communication system for obtaining and transmitting synchronization information is provided. The method includes obtaining synchronization information from a first communication network, and transmitting the synchronization information to a second communication network. The synchronization information is updated based on an obtainment time from the first communication network and a transmission time to the second communication network. The UE operates as a device-side time sensitive networking (TSN) translator (DS-TT).

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is based on and claims priority under 35 U.S.C. § 119(a) of a Korean patent application number 10-2020-0126325, filed on Sep. 28, 2020, in the Korean Intellectual Property Office, the disclosure of which is incorporated by reference herein in its entirety.

BACKGROUND

The disclosure relates to a communication system. More particularly, the disclosure relates to an apparatus and a method for providing time synchronization between communication nodes, which are connected to a 5thgeneration system (5GS) or of which future connections are scheduled, through expansion of a function of supporting a time sensitive network (TSN) of the 3rdGeneration Partnership Project (3GPP) 5GS.

2. Description of Related Art

To meet the ever-increasing demand for wireless data traffic since the commercialization of 4th generation (4G) communication systems, efforts have been made to develop improved 5thgeneration (5G) or pre-5G communication systems. As such, 5G or pre-5G communication systems are also called “beyond 4G network system” or “post Long-Term Evolution (LTE) system”. To achieve high data rates, 5G communication systems are being considered for implementation in the extremely high frequency (millimeter (mm) Wave) band (e.g., 60 gigahertz (GHz) band). To decrease path loss of radio waves and increase the transmission distance in the mmWave band, various technologies including beamforming, massive multiple-input multiple-output (massive MIMO), full dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and large-scale antennas are considered for 5G communication systems. In addition, to improve system networks in 5G communication systems, technology development is under way regarding evolved small cells, advanced small cells, cloud radio access networks (cloud radio access networks (RANs)), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, moving networks, cooperative communication, coordinated multi-points (CoMP), interference cancellation, and the like. Additionally, advanced coding and modulation (ACM) schemes, such as hybrid frequency shift keying and quadrature amplitude modulation (FQAM) and sliding window superposition coding (SWSC), and advanced access technologies, such as filter bank multi carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) are also under development for 5G systems.

Meanwhile, the Internet is evolving from a human centered network where humans create and consume information into the Internet of Things (IoT) where distributed elements, such as things exchange and process information. There has also emerged the Internet of Everything (IoE) technology that combines IoT technology with big data processing technology through connection with cloud servers. To realize IoT, technology elements related to sensing, wired/wireless communication and network infrastructure, service interfacing, and security are needed, and technologies interconnecting things, such as sensor networks, machine-to-machine (M2M) or machine type communication (MTC) are under research in recent years. In IoT environments, it is possible to provide intelligent Internet technology services, which collect and analyze data created by interconnected things to add new values to human life. Through convergence and combination between existing information technologies and various industries, IoT technology may be applied to various areas, such as smart homes, smart buildings, smart cities, smart or connected cars, smart grids, health-care, smart consumer electronics, and advanced medical services.

Accordingly, various attempts are being made to apply 5G communication systems to IoT networks. For example, sensor networks and machine-to-machine (M2M) or machine type communication (MTC) are being realized by use of 5G communication technologies including beamforming, MIMO, and array antennas. Application of cloud RANs as a big data processing technique described above may be an instance of convergence of 5G technology and IoT technology.

SUMMARY

Aspects of the disclosure are to address at least the above-mentioned problems and/or disadvantages and to provide at least the advantages described below. Accordingly, an aspect of the disclosure is to provide a method for transferring a precision time protocol (PTP) or a PTP message from the inside of a 3GPP network (5GS) in case that the 3GPP network, for example, a communication node of the 5GS, becomes a synchronization source, that is, operates as a network-side TSN translator (NW-TT) or a device-side TSN translator (DS-TT), and generates and provides a precision time protocol (PTP) or a generic PTP (gPTP) message to a communication node of an external network of the 5GS.

In accordance with an aspect of the disclosure, a method of a user equipment (UE) in a communication system for obtaining and transmitting synchronization information is provided. The method includes obtaining synchronization information from a first communication network, and transmitting the synchronization information to a second communication network. The synchronization information is updated based on an obtainment time from the first communication network and a transmission time to the second communication network. The UE operates as a device-side TSN translator (DS-TT).

In accordance with another aspect of the disclosure, a method of a user plane function (UPF) in a communication system for obtaining and transmitting synchronization information is provided. The method includes obtaining synchronization information from a first communication network, and transmitting the synchronization information to a second communication network. The synchronization information is updated based on an obtainment time from the first communication network and a transmission time to the second communication network. The UPF operates as a network-side TSN translator (NS-TT).

According to an aspect of the disclosure, the load of the UE/network and the current consumption of the UE can be reduced by suppressing the occurrence of traffics for the unnecessary PTP or gPTP message in the 5GS. Further, the possibility of erroneous designation of the UE of which the connection to the 5GS is scheduled can be reduced. Further, according to an aspect of the disclosure, the synchronization of the 5GS can be provided to an application in which the TSN is not supported, a video image audio professional application (VIAPA). More particularly, demand environments for various clock synchronizations (syncs) can be supported by providing synchronization with individual sync message types and sync precision through providing of the clock sync in different domains with respect to respective DS-TT ports and NW-TT ports. For example, the 5GS can provide the sync in the unit of 1 μs for factory automation with respect to communication nodes of a wired network, and can provide the sync in the unit of 100 μs for audio services with respect to communication nodes of a wireless network.

Other aspects, advantages, and salient features of the disclosure will become apparent to those of skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses various embodiments of the disclosure.

DETAILED DESCRIPTION

In the following description, a term to identify a communication node or connection node, a term to denote network entities, a term to denote messages, a term to denote an interface between network entities, and a term to denote various types of identity information have been exemplified for convenience in explanation. Accordingly, the disclosure is not limited to the following terms, and other terms to denote targets having equivalent technical meanings may be used.

Hereinafter, for convenience in explanation, in the disclosure, terms and names defined in the 5thgeneration system (5GS) and new radio (NR) standards, which are the latest standards defined by the 3rdgeneration partnership project (3GPP) group among the currently existing communication standards, are used. However, the disclosure is not restricted by the terms and names, but may be equally applied to wireless communication networks complying with other standards. More particularly, the disclosure can be applied to the 3GPP 5GS/NR (5thgeneration mobile communication standards).

In order to support scenarios, such as factory automation, time synchronization of related communication nodes may be necessary. More particularly, in a situation in which precision work is demanded, time synchronization of a high precision may be demanded. In case of utilizing Ethernet for industrial use, a time sensitive networking (TSN) technology, which is a method for supporting time synchronization between nodes connected on Ethernet, has been researched, commercialized, and used.

FIG.1is a conceptual diagram illustrating a principle of time synchronization on Ethernet of a time-sensitive networking (TSN) according to an embodiment of the disclosure.

Referring toFIG.1, TSN nodes100,110, and120may determine grand masters (GMs)200,210, and230that become the standard. For example, TSN node0100may input the current time of the GM200to a timestamp field. The TSN node0100may generate a sync frame by inputting 0 to a correlation field. The TSN node0100may transmit the sync frame to a next node. TSN node1110that is the next node may receive the sync frame, in which link delay 1 occurs, from the TSN node0100. The TSN node1110may transmit the sync frame to the next node by updating the correlation field based on residence time1that is a time in which the TSN node1resides in its own node. TSN node2120that is the next node may receive the sync frame, in which link delay 2 occurs, from the TSN node1110. The TSN node2120may transmit the sync frame to the next node by updating the correlation field based on residence time2that is a time in which the TSN node2resides in its own node. The respective nodes100,110, and120may periodically measure a delay time by a link with the previous node, and calculate and manage an average of the delay times. Further, the respective nodes100,110, and120may calculate the residence time in their own nodes.

FIG.2is a conceptual diagram illustrating a scenario for supporting TSN time synchronization of a 5G network according to an embodiment of the disclosure.

Referring toFIG.2, a 5G network310may be applied to factory automation supporting mobility. For application to the factory automation, the 5G network may support a TSN. For example, the 5G network310may be connected to a factory network300and actuator A320. The 5G network310may be connected to controller B302through a TSN Ethernet switch301of the factory network300. The controller B302may control the actuator A320through the 5G network310.

FIG.3is a conceptual diagram illustrating a method for supporting TSN time synchronization of a 5G network according to an embodiment of the disclosure.

Referring toFIG.3, in a similar situation to that ofFIG.2, the 5G network may support the TSN. For example, the 5G network may be modeled as one TSN bridge (TSN node)100,110, and120ofFIG.1. For example, a UPF1300, gNB1200, and UE1100, which are entities of the 5G network, may support the TSN by updating the sync frame through correlation of the link delay and the residence time as one TSN node. The UPF1300, gNB1200, and UE1110in the 5G network may be synchronized with a common 5G GM210. For example, the gNB1200may be connected to a GPS. The UPF1300may be synchronized with the gNB1200by being connected to the gNB1200through the Ethernet-based TSN. The UE1100may be synchronized with the gNB1200through a process of transmitting and receiving a PHY frame. The UPF1300may be connected to the TSN node100of a wire network. The UE1100may be connected to the TSN node120of a wire network. Referring toFIG.3, GM200of the TSN may be located in the TSN node100connected to the UPF1300. The UPF1300may receive the sync frame from the previous TSN node100. The UPF1300may determine the time based on an 5G GM210of the received sync frame as an ingress time. The UPF1300may periodically calculate and manage a link delay with the previous TSN node100. The UPF1300may transmit the sync frame in which the ingress time and the link delay are reflected to the UE1100. The UE1100may determine the residence time in which the UE1100resides in the 5G network based on the time of the 5G GM210at the moment that the UE1100transmits the sync frame to the next TSN node120. The UE1100may transmit the sync frame to the next TSN node120by updating the correlation field based on the residence time and the link delay.

According to various embodiments of the disclosure, the UE1100may operate as the DS-TT. For example, the UE1100may be called the DS-TT or UE/DS-TT. The UPF1300may operate as the NW-TT. For example, the UPF1300may be called the NW-TT or UPF/NW-TT.

FIG.4is a conceptual diagram illustrating video, imaging and audio for professional applications (VIAPA) in which all communication nodes operating as 5G UE/DS-TT can generate a sync message based on a 5GS clock and transmit the sync message to an external network of 5GS in a communication system according to an embodiment of the disclosure.

Referring toFIG.4, devices used for the scene performance, such as cameras411and412, microphones421,422, and423, speakers432,432, and433, and a mixing system441, may be 5G UE/DS-TTs. For example, the above devices411,412,421,422,423,432,432, and433may receive a sync message from the 5G network400, and may maintain a clock sync with one another. The above devices411,412,421,422,423,432,432, and433may support a harmonious performance by adjusting the generation time of videos, audios, and images thereof.

FIG.5is a conceptual diagram illustrating VIAPA in which some UEs operating as 5G UE/DS-TT can generate a sync message based on a 5GS clock and provide the sync message to an external network of 5GS in a communication system according to an embodiment of the disclosure.

Referring toFIG.5, mixing systems441,442, and443may be 5G UE/DS-TT. Cameras411and413, microphones421,422, and423, and speakers431,432, and433may be connected to the adjacent mixing systems441,442, and443. Since the mixing systems441,442, and443operate as the 5G UE/DS-TT, they may receive the sync message from the 5G network400, and maintain the clock sync with one another. The cameras411and413, the microphones421,422, and423, and the speakers431,432, and433may receive the sync message from the adjacent mixing systems441,442, and443, and maintain the clock sync with one another. The respective devices411,413,421,422,423,431,432, and433connected to the mixing systems441,442, and443may support the harmonious performance by adjusting the generation time of videos, audios, and images thereof.

FIG.6is a conceptual diagram illustrating a configuration method for configuring a communication node of 5GS as a synchronization source in a communication system according to an embodiment of the disclosure.

Referring toFIG.6, in case that the 5GS interlocks with the TSN system, TSN AF102may interlock with a centralized network configuration (CNC) server101and exchange management information with the CNC server101.

According to various embodiments of the disclosure, DS-TT1101may be a separate entity that is physically or logically separated from UE1100. For example, the DS-TT1101and the UE1100may transmit and receive signals with each other. Further, the DS-TT1101may be a physical or logical entity included in the UE1100. NW-TT1301may be a separate entity that is physically or logically separated from UPF1300. For example, the NW-TT1301and the UPF1300may transmit and receive signals with each other. Further, the NW-TT1301may be a physical or logical entity included in the UPF1300.

The TSN AF102may read management information out of the NW-TT1301and the DS-TT1101. The TSN AF102may change the configuration by transmitting the management information to the NW-TT1301and the DS-TT1101.

If there is not the TSN AF102, the 5GS may interlock with an external application function (AF)1900through NEF1800. In this case, the NEF1800may perform a similar function to the function performed by the TSN AF102. For example, the NEF1800may exchange the management information with the NW-TT1301and the DS-TT1101. Further, the NEF1800may transmit the 5GS information to the external AF1900. The NEF1800may interlock with SMF1500, an access and mobility management function (AMF)1400, PCF1600, and UDR1702in order to apply requirements received from the external AF1900to the 5GS system. For example, the NEF1800may store necessary information in the UDR1702, and transmit updated information to UDM1701or the PCF1600through a notification process.

According to various embodiments of the disclosure, the UDM1701and the UDR1702may be combined with each other. For example, the UDM1701may be called UDR/UDM1700. The UDR1702may be called UDR/UDM1700.

FIG.7is a conceptual diagram illustrating a structure in which NW-TT generates a sync message and provides sync to an external network of NW-TT and an external network of DS-TT in 5GS in a communication system according to an embodiment of the disclosure.

Referring toFIG.7, UPF/NW-TT1300may generate and transmit a sync message in a direction in which wired nodes are connected. In this case, a time stamp of the sync message may indicate the time when the sync message is generated. At the same time, the UPF/NW-TT1300may perform a similar operation to the operation ofFIG.3. For example, the UPF/NW-TT1300may perform an operation corresponding to the operation of receiving TSN sync (sync message). Other operations of the UPF/NW-TT1300may be similar to the operations ofFIG.3. The UPF/NW-TT1300may input the time when the sync message arrives into an ingress time field, and transmit the ingress time field to the UE/DS-TT1100. In this case, the link delay included in the correlation field may be 0. The UE/DS-TT1100may determine a residence time that is a time in which the UE/DS-TT1100resides in the 5G network using an egress time that is a time when the UE/DS-TT1100transmits the sync message out of the 5GS. The UE/DS-TT1100may update the correlation field based on the residence time and the link delay, and transmit the sync frame to the next external TSN node120.

FIG.8is a conceptual diagram illustrating a structure in which NW-TT and DS-TT generate a sync message and provide sync to an external network of NW-TT and an external network of DS-TT in 5GS in a communication system according to an embodiment of the disclosure.

Referring toFIG.8, the UPF/NW-TT1300may generate and transmit the sync message in a direction in which wired nodes are connected. In this case, the time stamp of the sync message may indicate the time when the sync message is generated. Further, the UE/DS-TT1100may generate and transmit the sync message to external nodes connected to the UE/DS-TT1100. In this case, the time stamp of the sync message may indicate the time when the sync message is generated. The UPF/NW-TT1300and the UE/DS-TT1100may transmit and receive the sync message in a method that is the same as or similar to the method as described above throughFIG.7. Alternatively, the sync message may not be transmitted. If the sync message is not transmitted, the traffic generation may be reduced, and thus the load of the UE or communication equipment may be reduced and the power consumption may be reduced.

FIG.9is a conceptual diagram illustrating a structure in which NW-TT generates a sync message and provides sync to an external network of DS-TT in 5GS in a communication system according to an embodiment of the disclosure.

Referring toFIG.9, UPF/NW-TT1300may generate the sync message, but may not transmit the sync message in the direction in which the wired nodes are connected. In this case, the time stamp of the sync message may indicate the time when the sync message is generated. At the same time, the UPF/NW-TT1300may perform a similar operation to the operation ofFIG.3. For example, the UPF/NW-TT1300may perform an operation corresponding to the operation of receiving the TSN sync message. Other operations of the UPF/NW-TT1300may be similar to the operations ofFIG.3. The UPF/NW-TT1300may input the time when the sync message arrives into the ingress time field, and transmit the ingress time field to the UE/DS-TT1100. In this case, the link delay included in the correlation field may be 0. The UE/DS-TT1100may determine the residence time that is the time in which the UE/DS-TT1100resides in the 5G network based on the egress time that is the time when the UE/DS-TT1100transmits the sync message out of the 5GS. The UE/DS-TT1100may update the correlation field based on the residence time and the link delay, and transmit the sync frame to the next external TSN node120.

FIG.10is a conceptual diagram illustrating a structure in which DS-TT generates a sync message and provides sync to an external network of DS-TT in 5GS in a communication system according to an embodiment of the disclosure.

Referring toFIG.10, the UE/DS-TT1100may generate and transmit the sync message to the external nodes connected to the UE/DS-TT1100. In this case, the time stamp of the sync message may indicate the time when the sync message is generated. The UPF/NW-TT1300may not generate the sync message. Further, the UPF/NW-TT1300may generate the sync message, but may not transmit the sync message in the direction in which the wired nodes are connected. In this case, the time stamp of the sync message may indicate the time when the sync message is generated. The UPF/NW-TT1300and the UE/DS-TT1100may not transmit the sync message with each other in the method described above with reference toFIG.9. If the sync message is not transmitted, the traffic generation may be reduced, and thus the load of the UE or communication equipment may be reduced, and the power consumption may be reduced. The TSN AF102or the NEF1800may be configured to operate the UE/DS-TT1100as the GM master210. The UPF/NW-TT1300may be configured in a passive or disabled state.

FIG.11is a conceptual diagram illustrating a structure in which DS-TT generates a sync message and provides sync to an external network of DS-TT by using a PDU session that utilizes a control plane using a logical UPF in 5GS in a communication system according to an embodiment of the disclosure.

Referring toFIG.11, the UE/DS-TT1100may generate and transmit the sync message to the external nodes connected to the UE/DS-TT1100. In this case, the time stamp of the sync message may indicate the time when the sync message is generated. By using the PDU session using the control plane, the logical UPF1300may be allocated. The logical NW-TT1301may be allocated to the UPF1300. However, the NW-TT1301may not generate the sync message, and may not transmit the sync message in the direction in which the wired nodes are connected. The NW-TT1301and the DS-TT1101may not transmit the sync message with each other in the method described above with reference toFIG.7or9. Since the sync message is not transmitted, the traffic generation may be reduced, and thus the load of the UE or network entity may be reduced, and the power consumption may be reduced. In this case, a PDU session that utilizes a control plane using the logical UPF1300is used, and the TSN AF102or the NEF1800may be configured to operate the DS-TT(1101) as the GM master201. The NW-TT1301of the logical UPF1300may be configured to be in a passive or disabled state. In this case, the TSN AF102or the NEF1800may configure the logical UPF1300or the NW-TT1301.

FIG.12is a conceptual diagram illustrating a structure in which DS-TT generates a sync message and provides sync to an external network of DS-TT by using a PDU session that utilizes a control plane using an NEF in 5GS in a communication system according to an embodiment of the disclosure.

Referring toFIG.12, the DS-TT1101may generate and transmit the sync message to the external nodes120connected to the DS-TT1101. In this case, the time stamp of the sync message may indicate the time when the sync message is generated. By using the PDU session using the control plane, the logical UPF1300may be allocated. The logical NW-TT1301may be allocated to the UPF1300. However, the NW-TT1301may not generate the sync message, and may not transmit the sync message in the direction in which the wired nodes are connected. The NW-TT1301and the DS-TT1101may not transmit the sync message with each other in the method described above with reference toFIG.7or9. Since the sync message is not transmitted, the traffic generation may be reduced, and thus the load of the UE or network entity may be reduced, and the power consumption may be reduced. In this case, by using the PDU session that utilizes the control plane using the NEF1800, the TSN AF102or the NEF1800may be configured to operate the DS-TT(1101) as the GM master201. Since there is not the UPF1300, the allocation of the 5GS bridge ID or the state of the NW-TT1301may be managed by the TSN AF102or the NEF1800.

FIG.13is a conceptual diagram illustrating a structure in which DS-TT generates a sync message and provides sync to an external network of DS-TT without a PDU session in 5GS in a communication system according to an embodiment of the disclosure.

Referring toFIG.13, the UE/DS-TT1100may generate and transmit the sync message to the external nodes120connected to the UE/DS-TT1100. In this case, the time stamp of the sync message may indicate the time when the sync message is generated. In this case, the UE/DS-TT1100can be only registered in the 5G system in a state where there is not the PDU session. The NW-TT1301and the UE1100or the DS-TT1101may not transmit the sync message with each other in the method described above with reference toFIG.7or9. Since the sync message is not transmitted, the traffic generation may be reduced, and thus the load of the UE or network entity may be reduced, and the power consumption may be reduced. In this case, since there is not the UPF1300, the allocation of the 5GS bridge ID or the state of the NW-TT1301may be managed by the TSN AF102or the NEF1800.

FIG.14is a flowchart illustrating an embodiment of utilizing an UDR notification in case that NW-TT or NW-TT and DS-TT generate a sync message and provide sync to an external network of NW-TT and an external network of DS-TT in 5GS in a communication system according to an embodiment of the disclosure.

This embodiment may correspond to a case of using the structure ofFIG.7or8.

Referring toFIG.14, at operation S1401, the AF1900may transmit an activation/deactivation request of a 5GS sync service to the NEF1800. In this case, added conditions may include the following contents.Valid time: Valid period of the request and the likeData network name (DNN)/single-network slice selection assistance information (S-NSSAI): Data network name and network slice (Network Slice_ID) of a protocol data unit (PDU) sessionUE ID(s): Target UE ID (generic public subscription identifier (GPSI) or others) and the likeGroup ID(s): External group ID designated by AF and the likeUE capability: Sync support, DS-TT support, DS-TT GM support, sync generation support, and the likeUE type: Sync UE, TSC and IoT UE, and the likeUE indication: Indication indicating that the sync service is necessary, and the likeTracking area identity (TAI): Location on the 5G system of cell ID based target UELocation: Physical location of UEApplication ID: Application ID requested by AFGM: Denoting whether to use a 5G GM or an external TSN GMMaster port: NW-TT/DS-TT portSync message format: gPTP/PTPSync domain: Domain 1 (domain1) (time sync domain that may be omitted)DST IP information 1 (Info1): IP address of an external node that becomes a target when a PTP message is usedSync accuracy: Time stamp period or granularity

At operation S1402, the NEF1800may convert some of conditions received at operation S1401. The generic public subscription identifier (GPSI) may be converted into an international mobile subscriber identity (IMSI) being used inside the 5GS. The external group ID may be converted into the internal group ID being used inside the 5GS. The sync clock domain provided from the AF1900may be converted by the NEF1800. The NEF1800may separately allocate a domain number (domain #n) to a combination of various conditions, such as UE ID, group ID, DNN/S-NSSAI, and valid time. When the AF1900requests activation of the sync based on the 5G GM clock201, it may specify or may not specify the separate domain. The NEF1800having received the request may separately allocate the domain number (domain #n) so that the domain number does not collide with the domain ID already allocated to the 5GS bridge.

At operation1403, the NEF1800may store conditions including a valid time, subscription permanent identifier (SUPI), domain number (domain #n), and the like in the unified data repository (UDR), and if needed, it may notify the unified data management (UDM)1700of the UDR, or may transmit the notification to the policy control function (PCF)1600later.

At operation S1403a, the NEF1800may transmit, to the AF1900, a response notifying that the requested contents including the converted domain number (domain #n) have been reflected in the 5GS.

At operation S1404, the UE/DS-TT1100may transmit a PDU session request to the SMF1500. The request may include conditions, such as DNN/S-NSSAI, PDU session type, DS-TT capability, device type, and the like. The SMF1500may determine whether to proceed with a later PDU session process by obtaining and comparing subscriber information from the UDM1700. If it is determined to continue the proceeding, The SMF1500may register the corresponding PDU session in the UDM1700. Further, in accordance with the request, a policy session between the SMF1500and the PCF1600may be configured.

At operation S1405, the UDR1700may determine whether the conditions including the valid time match one another based on the information transferred through the UDM1700when the PDU session is registered.

At operation S1406, sync activation may be performed to match the matching conditions. For example, at operation S1406a, the UDR1700may transmit the notification to the PCF1600. At operation S1406b−1, the PCF1600may notify the SMF1500that the policy has been updated. At operation S1406b−2, the PCF1600may notify the NEF1800that a new PDU session has been generated. The NEF1800may receive necessary information about the new PDU session from the DS-TT1100/NW-TT1300. According to another embodiment of the disclosure, the operation S1406b−2 may be omitted. At operation S1406c, the SMF1500may transmit a sync activation request to the UPF/NW-TT1300. In this case, a bridge management information container (BMIC) or a port management information container (PMIC) for the domain number (domain #n) may be used. If it is determined that the NEF1800directly transmits the information to the new PDU session at operation S1406b−2, the process may be the process in which the information transferred by the NEF1800to the SMF1500through the PCF1600is transferred by the SMF1500. At operation S1406d, the SMF1500may transmit the sync activation request to the UE/DS-TT1100. In this case, the PMIC for the domain number (domain #n) may be used. If it is determined that the NEF1800directly transmits the information to the new PDU session at operation S1406b−2, the process may be the process in which the information transmitted by the NEF1800to the SMF1500through the PCF1600is transmitted by the SMF1500.

At operation S1407a, the UPF/NW-TT1300may generate and transmit the sync message based on the 5G GM clock to an outside of the NW-TT1300in accordance with the conditions configured at operation S1406. In this case, the time stamp of the sync message may indicate the time when the sync message is generated. The domain may be configured as the domain number (domain #n) allocated from the NEF1800. At the same time, the NW-TT1300may perform an operation corresponding to the operation of receiving the TSN sync message as shown inFIG.3. The NW-TT1300may input the time when the sync message arrives into the ingress time field, and transmit the ingress time field to the DS-TT1100. Since the time generated based on the same 5G GM clock201is the arrival time, the ingress time field may have the same value. Alternatively, the ingress time field may be omitted. In this case, the link delay included in the correlation field of the sync message may be 0.

At operation S1407a, the UPF/NW-TT1300may operate in accordance with the conditions configured at operation S1406. The NW-TT1300and the DS-TT1100may transmit and receive the sync message with each other in the method as described above with reference toFIG.7. Alternatively, the sync message may not be transmitted. If the sync message is not transmitted, the traffic generation may be reduced, and thus the load of the UE or network entity may be reduced, and the power consumption may be reduced.

At operation S1407a, the UPF/NW-TT1300may be the subject that transmits the sync to the outside. Accordingly, the UPF/NW-TT1300may be configured to periodically transmit an announce message for the best master clock algorithm (BMCA) based on the 5G GM clock having a master port status.

At operation S1407b, the DS-TT1100may determine the residence time that is the time in which the DS-TT1100resides in the 5G network using the egress time that is the time when the sync message transmitted by the NW-TT at operation S1407ais transmitted to the outside of the 5GS. The UE/DS-TT may transmit the sync frame to the next external TSN node by updating the correlation field based on the residence time and the link delay.

In accordance with the conditions configured at operation S1406, the DS-TT1100, at operation S1407b, may generate and transmit the sync message to the external nodes connected to the DS-TT1100. In this case, the time stamp of the sync message may indicate the time when the sync message is generated. The NW-TT1300and the DS-TT1100may transmit the sync message to each other in the method described above with reference toFIG.7. Alternatively, the sync message may not be transmitted. If the sync message is not transmitted, the traffic generation may be reduced, and thus the load of the UE or network entity may be reduced, and the power consumption may be reduced.

At operation S1407b, the UE/DS-TT1100is the subject that transmits the sync to the outside. Accordingly, the UE/DS-TT1100may be configured to periodically transmit the announce message for the BMCA based on the 5G GM clock201having the master port status.

At operation S1408a, the NW-TT1300may transmit the sync message and the announce message to an external node based on the configuration at operation S1407a.

At operation S1408b−1, the NW-TT1300may transmit the sync message to the DS-TT1100based on the configuration at operation S1407a.

At operation S1408b−2, the UE/DS-TT1100may transmit the sync message and the announce message to the outside based on the configuration at operation S1407b.

FIG.15is a flowchart illustrating an embodiment of utilizing a PDU session response in case that NW-TT or NW-TT and DS-TT generate a sync message and provide sync to an external network of NW-TT and an external network of DS-TT in 5GS in a communication system according to an embodiment of the disclosure.

This embodiment may correspond to a case of using the structure ofFIG.7or8.

Referring toFIG.15, operation S1501may be the same as or similar to operation S1401ofFIG.14.

Operation S1502may be the same as or similar to operation S1402ofFIG.14.

Operation S1503may be the same as or similar to operation S1403ofFIG.14.

Operation S1503amay be the same as or similar to operation S1403aofFIG.14.

At operation S1504, the UE/DS-TT1100may transmit a PDU session request to the SMF1500. The request may include conditions, such as DNN/S-NSSAI, PDU session type, capability of the DS-TT1100, device type, and the like. At operation S1504a, the SMF1500may receive subscription information from the UDM1700.

At operation S1505, the SMF1500may determine whether a PDU session establishment request matches the conditions including the valid time.

At operation S1506, the SMF1500may perform the sync activation based on the matching conditions. For example, at operation1506a, the SMF1500may perform policy association with the PCF1600. At operation S1506b, the SMF1500may transmit the sync activation request to the UPF/NW-TT1100. In this case, the SMF1500may use the bridge management information container (BMIC) or the port management information container (PMIC) for the domain number (domain #n). At operation S1506c, the SMF1500may transmit the sync activation request to the UE/DS-TT. In this case, the SMF1500may use the PMIC for the domain number (domain #n).

Operation S1507amay be the same as or similar to operation S1407aofFIG.14.

Operation S1507bmay be the same as or similar to operation S1407bofFIG.14.

Operation S1508amay be the same as or similar to operation S1408aofFIG.14.

Operation S1508b−1 may be the same as or similar to operation S1408b-1ofFIG.14.

Operation S1508b−2 may be the same as or similar to operation S1408b-2ofFIG.14.

FIG.16is a flowchart illustrating an embodiment of utilizing a UDR notification in case that NW-TT or DS-TT generates a sync message and provides sync to an external network of DS-TT in 5GS in a communication system according to an embodiment of the disclosure.

This embodiment may correspond to a case of using the structure ofFIG.9or10.

Referring toFIG.16, at operation S1601, the AF may transmit an activation/deactivation request of a 5GS sync service to the NEF. In this case, added conditions may include the following contents.Valid time: Valid period of the request and the likeDNN/S-NSSAI: Data network name and network slice ID of a PDU sessionUE ID(s): Target UE ID (GPSI or others) and the likeGroup ID(s): External group ID designated by AF and the likeUE capability: Sync support, DS-TT support, DS-TT GM support, sync generation support, and the likeUE type: Sync UE, TSC and IoT UE, and the likeUE indication: Indication indicating that the sync service is necessary, and the likeTAI: Location on the 5G system of cell ID based target UELocation: Physical location of UEApplication ID: Application ID requested by AFGM: Denoting whether to use a 5G GM or an external TSN GMMaster port: NW-TT/DS-TT portSync message format: gPTP/PTPSync domain: domain1 (time sync domain that may be omitted)DST IP Info1: IP address of an external node that becomes a target when a PTP message is usedSync accuracy: Time stamp period or granularity

At operation S1602, the NEF may convert some information of conditions received at operation S1601. The GPSI may be converted into an IMSI being used inside the 5GS. The external group ID may be converted into the internal group ID being used inside the 5GS. The sync clock domain provided from the AF1900may be converted by the NEF1800. The NEF1800may separately allocate a domain number (domain #n) to a combination of various conditions, such as UE ID, group ID, DNN/S-NSSAI, and valid time. When the AF1900requests activation of the sync based on the 5G GM clock200, it may specify or may not specify the separate domain. The NEF1800having received the request may separately allocate the domain number (domain #n) so that the domain number does not collide with the domain ID already allocated to the 5GS bridge.

At operation1603, the NEF1800may store conditions including a valid time, SUPI, domain number (domain #n), and the like in the UDR1700, and if needed, it may notify the UDM1700of the UDR1700, or may transmit the notification to the PCF1600later.

At operation S1603a, the NEF1800may transmit, to the AF, a response notifying that the requested contents including the converted domain number (domain #n) have been reflected in the 5GS.

At operation S1604, the UE/DS-TT1100may transmit a PDU session request to the SMF1500. The request may include conditions, such as DNN/S-NSSAI, PDU session type, capability of the DS-TT1100, device type, and the like. The SMF1500may determine whether to proceed with a later PDU session process by obtaining subscriber information from the UDM1700and comparing the subscriber information with the above-described conditions. If it is determined to proceed with the PDU session process, The SMF1500may register the corresponding PDU session in the UDM1700. Further, in accordance with the request, the SMF1500may configure a policy session between the SMF1500and the PCF1600.

At operation S1605, the UDR1700may determine whether the conditions including the valid time match one another based on the information transferred through the UDM1700when the SMF1500registers the PDU session.

At operation S1606, sync activation may be performed based on the matching conditions. For example, at operation S1606a, the UDR1700may transmit the notification to the PCF1600. At operation S1606b−1, the PCF1600may notify the SMF1500that the policy has been updated. At operation S1606b−2, the PCF1600may notify the NEF1800that a new PDU session has been generated. The NEF1800may obtain necessary information about the new PDU session from the DS-TT1100/NW-TT1300. Operation S1606b−2 may be omitted. At operation S1606c, the SMF1500may transmit a sync activation request to the UPF/NW-TT1100. In this case, the SMF1500may use a bridge management information container (BMIC) or a port management information container (PMIC) for the domain number (domain #n). In this case, since the port status of the NW-TT1300is configured to be disable, the sync message may not be transferred to an outside of the NW-TT1300. If the NEF1800directly transfers the information to the new PDU session at operation S1606b−2, the process may be the process in which the SMF1500retransfers the information that the NEF1800has transferred to the SMF1500through the PCF1600to the UPF/NW-TT1100. At operation S1606d, the SMF1500may transmit the sync activation request to the UE/DS-TT1100. In this case, the SMF1500may use the PMIC for the domain number (domain #n). If the NEF1800directly transfers the information to the new PDU session at operation S1606b−2, the process may be the process in which the SMF1500retransfers the information that the NEF1800has transferred to the SMF1500through the PCF1600to the UE/DS-TT1100.

At operation S1607a, the UPF/NW-TT1300may generate the sync message based on the 5G GM clock210based on the conditions configured at operation S1606, but may not transfer the sync message to an outside of the NW-TT1300. In this case, the time stamp of the sync message may indicate the time when the sync message is generated. The domain may be configured as the domain number (domain #n) allocated from the NEF1800. At the same time, the NW-TT1300may perform an operation corresponding to the operation of receiving the TSN sync message as shown inFIG.3. For example, the NW-TT1300may input the time when the sync message arrives into the ingress time field, and transmit the ingress time field to the DS-TT1100. Since the time generated based on the same 5G GM clock210is the arrival time, the same value may be inputted. The ingress time field may be omitted. In this case, the link delay included in the correlation field of the sync message may be 0.

At operation S1607a, the UPF/NW-TT1300may operate based on the conditions configured at operation S1606. For example, the NW-TT1300and the DS-TT1100may transmit and receive the sync message with each other in the method as described above with reference toFIG.7. Alternatively, the sync message may not be transmitted. If the sync message is not transmitted, the traffic generation may be reduced, and thus the load of the UE or network entity may be reduced, and the power consumption may be reduced.

At operation S1607a, since the UPF/NW-TT1300may be the subject that transmits the sync to the outside, it may be configured to periodically transmit an announce message for the BMCA based on the 5G GM clock210having a master port status.

At operation S1607b, the DS-TT1100may determine the residence time that is the time in which the DS-TT1100resides in the 5G network using the egress time that is the time when the sync message received from the NW-TT1300at operation S1607ais transmitted to the outside of the 5GS. The UE/DS-TT1100may transmit the sync frame to the next external TSN node by updating the correlation field based on the residence time and the link delay.

Based on the configuration conditions at operation S1606, the DS-TT1100, at operation S1607b, may generate and transmit the sync message to the external nodes connected to the DS-TT1100. In this case, the time stamp of the sync message may indicate the time when the time stamp of the sync message is generated. NW-TT1300and the DS-TT1100may transmit the sync message with each other in the method described above with reference toFIG.7. Alternatively, the sync message may not be transmitted. If the sync message is not transmitted, the traffic generation may be reduced, and thus the load of the UE or network entity may be reduced, and the power consumption may be reduced.

At operation S1607b, since the UE/DS-TT1100is the subject that transmits the sync to the outside, it may be configured to periodically transmit the announce message for the BMCA based on the 5G GM clock210having the master port status.

At operation S1608a, the NW-TT1300may transmit the sync message and the announce message to an external node as configured at operation S1607a.

At operation S1608b-1, the NW-TT1300may transmit the sync message to the DS-TT1100as configure at operation S1607a.

At operation S1608b-2, the UE/DS-TT1100may transmit the sync message and the announce message to the outside as configured at operation S1607b.

FIG.17is a flowchart illustrating an embodiment of utilizing a PDU session request (session response) in case that NW-TT or DS-TT generates a sync message and provides sync to an external network of DS-TT in 5GS in a communication system according to an embodiment of the disclosure.

This embodiment may correspond to a case of using the structure ofFIG.9or10.

Referring toFIG.17, operation S1701may be the same as or similar to operation S1601ofFIG.16.

Operation S1702may be the same as or similar to operation S1602ofFIG.16.

Operation S1703may be the same as or similar to operation S1603ofFIG.16.

Operation S1703amay be the same as or similar to operation S1603aofFIG.16.

At operation S1704, the UE/DS-TT1100may transmit a PDU session establishment request to the SMF1500. The request may include conditions, such as DNN/S-NSSAI, PDU session type, DS-TT capability, device type, and the like. At operation S1704a, the SMF1500may request and receive subscription information from the UDM1700.

At operation S1705, the SMF1500may determine whether a PDU session establishment request matches the conditions including the residence time (valid time).

At operation S1706, the sync activation may be performed based on the matching conditions. For example, at operations1706aand S1706b, the SMF1500may perform policy association with the PCF1600. At operation S1706c, the SMF1500may transmit the sync activation request to the UPF/NW-TT1300. In this case, the SMF1500may use the bridge management information container (BMIC) or the port management information container (PMIC) for the domain number (domain #n). At operation S1706d, the SMF1500may transmit the sync activation request to the UE/DS-TT. In this case, the SMF1500may use the PMIC for the domain number (domain #n).

Operation S1707amay be the same as or similar to operation S1607aofFIG.16.

Operation S1707bmay be the same as or similar to operation S1607bofFIG.16.

Operation S1708amay be the same as or similar to operation S1608aofFIG.16.

Operation S1708b-1may be the same as or similar to operation S1608b-1ofFIG.16.

Operation S1708b-2may be the same as or similar to operation S1608b-2ofFIG.16.

FIG.18is a flowchart illustrating an embodiment of utilizing a UDR notification in case that DS-TT generates a sync message and provides sync to an outside of the DS-TT by using a PDU session that utilizes a control plane in 5GS in a communication system according to an embodiment of the disclosure.

This embodiment may correspond to a case of using the structure ofFIG.11or12.

Referring toFIG.18, at operation S1801, the AF1900may transmit an activation/deactivation request of a 5GS sync service to the NEF1800. In this case, added conditions may include the following contents.Valid time: Valid period of the request and the likeDNN/S-NSSAI: Data network name and network slice ID of a PDU sessionUE ID(s): Target UE ID (GPSI or others) and the likeGroup ID(s): External group ID designated by AF and the likeUE capability: Sync support, DS-TT support, DS-TT GM support, sync generation support, and the likeUE type: Sync UE, TSC and IoT UE, and the likeUE indication: Indication indicating that the sync service is necessary, and the likeTAI: Location on the 5G system of cell ID based target UELocation: Physical location of UEApplication ID: Application ID requested by AFGM: Denoting whether to use a 5G GM or an external TSN GMMaster port: NW-TT/DS-TT portSync message format: gPTP/PTPSync domain: domain1 (time sync domain that may be omitted)DST IP Info1: IP address of an external node that becomes a target when a PTP message is usedSync accuracy: Time stamp period or granularity

At operation S1802, the NEF1800may convert some of conditions received at operation S1801. For example, the GPSI may be converted into an IMSI being used inside the 5GS. The external group ID may be converted into the internal group ID being used inside the 5GS. The sync clock domain provided from the AF1900may be converted by the NEF1800. The NEF1800may separately allocate a domain number (domain #n) to a combination of various conditions, such as UE ID, group ID, DNN/S-NSSAI, and valid time. When the AF1900requests activation of the sync based on the 5G GM clock210, it may specify or may not specify the separate domain. The NEF1800having received the request may allocate the separate domain number (domain #n) so that the domain number does not collide with the domain ID already allocated to the 5GS bridge. Further, in case that the logical UPF1300is used as inFIG.11, the bridge ID may be allocated by the logical UPF1300, the SMF1500, or the NEF1800. Further, in case that the logical UPF1300is not used, but the PDU session that uses the control plane using the NEF1800is used as inFIG.12, the bridge ID may be allocated by the NEF1800or the SMF1500.FIG.18illustrates a case that the NEF1800allocates the bridge ID number (#n). At operation S1803, the NEF1800may store conditions including a valid time, SUPI, domain number (domain #n), and the like in the UDR1700, and if needed, it may notify the UDM1700of the UDR1700, or may provide the notification to the PCF1600later.

At operation S1803a, the NEF1800may transmit, to the AF1900, a response notifying that the received contents including the converted domain number (domain #n) have been reflected in the 5GS.

At operation S1804, the UE/DS-TT1100may transmit a PDU session request to the SMF1500. The request may include conditions, such as DNN/S-NSSAI, PDU session type, DS-TT capability, device type, and the like. Based on the request, the policy session between the SMF1500and the PCF1600may be configured. The SMF1500may determine whether to proceed with a later PDU session process by receiving subscriber information from the UDM1700and comparing the subscriber information with the above conditions. In case of proceeding with the process, the SMF1500may register the corresponding PDU session in the UDM1700. In this case, the SMF1500may determine the PDU session that uses the logical UPF1300and the control plane or the PDU session based on the control plane using the NEF1800by checking the information received from the UDM1700. Further, based on the request, the policy session between the SMF1500and the PCF1600may be configured.

At operation S1805, the UDR1700may determine whether the conditions including the valid time match one another based on the information transferred through the UDM1700when the PDU session is registered.

At operation S1806, sync activation may be performed based on the matching conditions. For example, at operation S1806a, the UDR1700may transmit the notification to the PCF1600. At operation S1806b−1, the PCF1600may notify the SMF1500that the policy has been updated. At operation S1806b−2, the PCF1600may notify the NEF1800that a new PDU session has been generated. The NEF1800may receive necessary information about the new PDU session from the DS-TT1100/NW-TT1300. Operation S1806b−2 may be omitted. In case of using the configuration ofFIG.12, the SMF1500, at operation S1806b−3, may configure a connection with the NEF1800based on Nnef_SMContext_Create. In case of using the configuration ofFIG.11, operation S1806b−3 may be omitted. In case of using the configuration ofFIG.11, the SMF1500, at operation S1806c, may transmit the sync activation request to the logical UPF/MW-TT1300. In this case, the SMF1500may use a bridge management information container (BMIC) or a port management information container (PMIC) for the domain number (domain #n). In this case, the SMF1500may not transmit the sync message to the outside of the NW-TT1300by configuring the port status of the logical NW-TT1300to be disable. If the NEF1800directly transfers the information through the new PDU session at operation S1806b−2, the process may be the process in which the SMF transfers the information that the NEF1800has transferred to the SMF through the PCF1300. In case of the configuration ofFIG.12, operation S1806cmay be omitted. AT operation S1806d, the SMF1500may transmit the sync activation request to the UE/DS-TT1100. In this case, the SMF1500may use the PMIC for the domain number (domain #n). If the NEF1800directly transfers the information through the new PDU session at operation S1806b−2, the process may be the process in which the SMF1500transfers the information that the NEF1800has transferred to the SMF1500through the PCF1600.

At operation S1807a, the logical UPF/NW-TT1100may not generate the sync message based on the 5G GM clock210based on the conditions configured at operation S1806, and may not transfer the sync message to the outside of the NW-TT1300.

Since the NW-TT1300and the DS-TT1100do not transmit the sync message to each other, the traffic generation may be reduced, and thus the load of the UE or network entity may be reduced, and the power consumption may be reduced.

At operation S1807a, since the UPF/NW-TT1300does not transmit the sync to the outside, it may be configured not to periodically transmit the announce message for the BMCA based on the 5G GM clock210.

At operation S1807b, the DS-TT1100may generate and transmit the sync message to the external nodes connected to the DS-TT1100. In this case, the time stamp of the sync message may indicate the time when the sync message is generated. The NW-TT1300and the DS-TT1100may not transmit the sync message with each other. If the sync message is not transmitted, the traffic generation may be reduced, and thus the load of the UE or network entity may be reduced, and the power consumption may be reduced.

At operation S1807b, since the UE/DS-TT1100may be the subject that transmits the sync to the outside, it may be configured to periodically transmit the announce message for the BMCA based on the 5G GM clock210having the master port status.

As configured at operation S1807b, the UE/DS-TT1100, at operation S1808, may transmit the sync message and the announce message to the outside.

FIG.19is a flowchart illustrating an embodiment of utilizing a PDU session request (session response) in case that DS-TT generates a sync message and provides sync to an external network of DS-TT by using a PDU session that utilizes a control plane in 5GS in a communication system according to an embodiment of the disclosure.

This embodiment may correspond to a case of using the structure ofFIG.11or12.

Referring toFIG.19, operation S1901may be the same as or similar to operation S1801ofFIG.18.

Operation S1902may be the same as or similar to operation S1802ofFIG.18.

Operation S1903may be the same as or similar to operation S1803ofFIG.18.

Operation S1903amay be the same as or similar to operation S1803aofFIG.18.

At operation S1904, the UE/DS-TT1100may transmit a PDU session establishment request to the SMF1500. The request may include conditions, such as DNN/S-NSSAI, PDU session type, DS-TT capability, device type, and the like.

At operation S1904a, the SMF1500may receive the corresponding contents by requesting subscription information from the UDM1700.

At operation S1905, the SMF1500may determine whether a PDU session establishment request matches the conditions including the valid time.

At operation S1906, the sync activation may be performed based on the matching conditions. At operations1906a, the SMF1500may perform policy association with the PCF1600. In case of using the configuration ofFIG.12, the SMF1500, at operation S1906b, may configure the connection with the NEF1800based on the Nnef_SMContext_Create. In case of using the configuration ofFIG.11, the SMF1500, at operation S1906c, may transmit the sync activation request to the UPF/NW-TT1300. In this case, the SMF1500may use the bridge management information container (BMIC) or the port management information container (PMIC) for the domain number (domain #n). At operation S1906d, the SMF1500may transmit the sync activation request to the UE/DS-TT1100. In this case, the SMF1500may use the PMIC for the domain number (domain #n).

Operation S1907amay be the same as or similar to operation S1807aofFIG.18.

Operation S1907bmay be the same as or similar to operation S1807bofFIG.18.

Operation S1908may be the same as or similar to operation S1808ofFIG.18.

FIG.20is a flowchart conceptual diagram illustrating an embodiment of utilizing a UDR notification in case that the DS-TT1100generates a sync message and provides sync to an external network of the DS-TT1100without a PDU session in 5GS in a communication system according to an embodiment of the disclosure.

This embodiment may correspond to a case of using the structure ofFIG.13.

Referring toFIG.20, at operation S2001, the AF1900may transmit an activation/deactivation request of a 5GS sync service to the NEF1800. In this case, added conditions may include the following contents.Valid time: Valid period of the request and the likeDNN/S-NSSAI: Data network name and network slice ID of a PDU sessionUE ID(s): Target UE ID (GPSI or others) and the likeGroup ID(s): External group ID designated by AF and the likeUE capability: Sync support, DS-TT support, DS-TT GM support, sync generation support, and the likeUE type: Sync UE, TSC and IoT UE, and the likeUE indication: Indication indicating that the sync service is necessary, and the likeTAI: Location on the 5G system of cell ID based target UELocation: Physical location of UEApplication ID: Application ID requested by AFGM: Denoting whether to use a 5G GM or an external TSN GMMaster port: NW-TT/DS-TT portSync message format: gPTP/PTPSync domain: domain1 (time sync domain that may be omitted)DST IP Info1: IP address of an external node that becomes a target when a PTP message is usedSync accuracy: Time stamp period or granularity

At operation S2002, the NEF1800may convert some information of conditions received at operation S2001. For example, the GPSI may be converted into an IMSI being used inside the 5GS. The external group ID may be converted into the internal group ID being used inside the 5GS. The sync clock domain provided from the AF1900may be converted by the NEF1800. The NEF1800may allocate a separate domain number (domain #n) to a combination of various conditions, such as UE ID, group ID, DNN/S-NSSAI, and residence time (valid time). When the AF1900transmits an activation request for the sync based on the 5G GM clock, it may specify or may not specify the separate domain. The NEF1800having received the request may allocate the separate domain number (domain #n) so that the domain number does not collide with the domain ID already allocated to the 5GS bridge.

At operation S2003, the NEF1800may store conditions including a valid time, SUPI, domain number (domain #n), and the like in the UDR1700, and if needed, it may notify the UDM1700of the UDR1700, or may provide the notification to the PCF1600later.

At operation S2003a, the NEF1800may transmit, to the AF1900, a response notifying that the requested contents including the converted domain number (domain #n) have been reflected in the 5GS.

At operation S2004, the UE/DS-TT1100may transmit a registration request to AMF1400. The request may include conditions, such as DNN/S-NSSAI, DS-TT capability, device type, and the like. In this case, the AMF1400may determine whether to continue proceeding with the registration process by obtaining and checking the subscriber information from the UDM1700. In this case, connection between the AMF1400and the PCF1600may be configured.

At operation S2005, the UDR1700may determine whether the conditions including the valid time match one another based on the information transferred through the UDM1700when the UE is registered.

At operation S2006, the sync activation may be performed based on the matching conditions. For example, at operation S2006a, the UDR1700may transmit the notification to the PCF1600. At operation S2006b−1, the PCF1600may notify the AMF1400that the policy has been updated. At operation S2006b−2, the PCF1600may notify the NEF1800that new UE has been registered. The NEF1800may obtain necessary information about the new UE from the DS-TT1100. Operation S2006b−2 may be omitted.

At operation S2006c, the AMF1400may transmit the sync activation request to the UE/DS-TT1100. In this case, the AMF1400may use the PMIC for the domain number (domain #n). If the NEF1800directly transmits new UE registration information to the NEF1800at operation S2006b−2, the process may be the process in which the AMF1400retransfers, to the UE/DS-TT1100, the information that the NEF1800has transferred to the AMF1400through the PCF1600.

At operation S2007, the DS-TT1100may generate and transmit the sync message to the external nodes connected to the DS-TT1100. In this case, the time stamp of the sync message may indicate the time when the sync message is generated. The NW-TT1300and the DS-TT1100may not transmit the sync message with each other. Since the sync message is not transmitted, the traffic generation may be reduced, and thus the load of the UE or network entity may be reduced, and the power consumption may be reduced.

At operation S2007, since the UE/DS-TT1100may be the subject that transmits the sync to the outside, it may be configured to periodically transmit the announce message for the BMCA based on the 5G GM clock210having the master port status.

As configured at operation S2007, the UE/DS-TT1100, at operation S2008, may transmit the sync message and the announce message to the outside.

FIG.21is a flowchart illustrating an embodiment of utilizing a registration response in case that DS-TT generates a sync message and provides sync to an external network of DS-TT without a PDU session in 5GS in a communication system according to an embodiment of the disclosure.

This embodiment may correspond to a case of using the structure ofFIG.13.

Referring toFIG.21, operation S2101may be the same as or similar to operation S2001ofFIG.20.

Operation S2102may be the same as or similar to operation S2002ofFIG.20.

Operation S2103may be the same as or similar to operation S2003ofFIG.20.

Operation S2103amay be the same as or similar to operation S2003aofFIG.20.

At operation S2104, the UE/DS-TT1100may transmit the registration request to the AMF1400. The request may include conditions, such as DNN/S-NSSAI, DS-TT capability, device type, and the like.

At operation S2104a, the AMF1400may obtain the subscriber information from the UDM1700.

At operation S2105, it may be identified whether the request matches the conditions including the valid time in accordance with the information transferred through the UDM1700when the UE is registered.

At operation S2106, the sync activation may be performed based on the matching conditions. For example, at operation S2106a, the AMF1400may configure the connection with the PCF1600.

At operations2106b, the AMF1400may transmit the sync activation request to the UE/DS-TT1100. In this case, the AMF1400may use the PMIC for the domain number (domain #n).

Operation S2107may be the same as or similar to operation S2007ofFIG.20.

Operation S2108may be the same as or similar to operation S2008ofFIG.20.

FIG.22is a block diagram illustrating UE in a communication system according to an embodiment of the disclosure.

Referring toFIG.22, UE1100may include a transceiver1110, a controller1120, and a memory1130. The UE1100may additionally have more constituent elements depending on an implementation method thereof. For example, various additional devices, such as a display for a user interface, an input unit, and sensors, may be further included. The disclosure is not limited to such additional configurations.

The transceiver1110may be connected to gNB1200on a wireless channel based on the respective embodiments described with reference toFIGS.1to21, and may perform transmission and reception of signals and/or messages with various kinds of network function devices through the gNB1200. In case that the UE1100communicates with the 5G network, the transceiver1110may be a device that can perform transmission/reception with the 5G communication network. Further, the transceiver1110, if needed, may include a communication processor.

In case that the transceiver1100does not include the communication processor, all signals and/or messages may be processed by the controller.

The controller1120may control the basic UE operations, and may control reception and storage of the messages described above with reference toFIGS.1to21. For example, the controller1120may perform the operations based on those as described above with reference toFIGS.1to21.

The memory1130may store various kinds of data necessary to control the UE1100, and may have an area for storing various kinds of information as described above with reference toFIGS.1to21.

FIG.23is a block diagram illustrating a gNB in a communication system according to an embodiment of the disclosure.

Referring toFIG.23, the gNB1200may include a transceiver1210, a controller1220, and a memory1230. The gNB1200may additionally have more constituent elements depending on an implementation method thereof. For example, various additional devices, such as a display for a user interface, an input unit, and sensors, may be further included. The disclosure is not limited to such additional configurations.

The transceiver1210may be connected to the UE on a wireless channel based on the respective embodiments described with reference toFIGS.1to21, and may perform transmission and reception of signals and/or messages with various kinds of network function devices. In case that the base station communicates with the 5G network, the transceiver1210may be a device that can perform transmission/reception with the 5G communication network. Further, the transceiver1210, if needed, may include a communication processor.

In case that the transceiver1210does not include the communication processor, all signals and/or messages may be processed by the controller.

The controller1220may control the basic operations of the gNB1200, and may control reception and storage of the messages described above with reference toFIGS.1to21. For example, the controller1220may perform the operations based on those as described above with reference toFIGS.1to21.

The memory1230may store various kinds of data necessary to control the gNB1200, and may have an area for storing various kinds of information as described above with reference toFIGS.1to21.

FIG.24is a block diagram illustrating a UPF in a wireless communication system according to an embodiment of the disclosure.

Referring toFIG.24, the UPF1300may perform communication with other network entities of a core network through a network interface1310. For example, the UPF1300may perform communication with UE1100, gNB1200, AMF1400, SMF1500, PCF1600, UDR/UDM1700, NEF1800, and AF1900.

A controller1320may be implemented by at least one processor or/and program for performing the operation of the UPF1300. For example, the controller1320may perform the operation of the UPF1300as described above with reference toFIGS.1to21.

A memory1330may store programs and various kinds of control information necessary for the controller1320, and in addition, may store various kinds of information as described above with reference toFIGS.1to21.

In addition to the configurations described above with reference toFIGS.1to21, the UPF1300may further include various interfaces for accesses by an operator. The disclosure does not have special restrictions on such additional configurations.

FIG.25is a block diagram illustrating an AMF in a wireless communication system according to an embodiment of the disclosure.

Referring toFIG.25, the AMF1400may perform communication with other network entities of a core network through a network interface1410. For example, the AMF1400may perform communication with UE1100, gNB1200, UPF1300, SMF1500, PCF1600, UDR/UDM1700, NEF1800, and AF1900.

A controller1420may be implemented by at least one processor or/and program for performing the operation of the AMF1400. For example, the controller1420may perform the operation of the AMF1400as described above with reference toFIGS.1to21.

A memory1430may store programs and various kinds of control information necessary for the controller1420, and in addition, may store various kinds of information as described above with reference toFIGS.1to21.

In addition to the configurations described above with reference toFIGS.1to21, the AMF1400may further include various interfaces for accesses by an operator. The disclosure does not have special restrictions on such additional configurations.

FIG.26is a block diagram illustrating an SMF in a wireless communication system according to an embodiment of the disclosure.

Referring toFIG.26, the SMF1500may perform communication with other network entities of a core network through a network interface1510. For example, the SMF1500may perform communication with UE1100, gNB1200, UPF1300, AMF1400, PCF1600, UDR/UDM1700, NEF1800, and AF1900.

A controller1520may be implemented by at least one processor or/and program for performing the operation of the SMF1500. For example, the controller1520may perform the operation of the SMF1500as described above with reference toFIGS.1to21.

A memory1530may store programs and various kinds of control information necessary for the controller1520, and in addition, may store various kinds of information as described above with reference toFIGS.1to21.

In addition to the configurations described above, the SMF1500may further include various interfaces for accesses by an operator. The disclosure does not have special restrictions on such additional configurations.

FIG.27is a block diagram illustrating a PCF in a wireless communication system according to an embodiment of the disclosure.

Referring toFIG.27, the PCF1600may perform communication with other network entities of a core network through a network interface1610. For example, the PCF1600may perform communication with UE1100, gNB1200, UPF1300, AMF1400, SMF1500, UDR/UDM1700, NEF1800, and AF1900.

A controller1620may be implemented by at least one processor or/and program for performing the operation of the PCF1600. For example, the controller1620may perform the operation of the PCF1600as described above with reference toFIGS.1to21.

A memory1630may store programs and various kinds of control information necessary for the controller1620, and in addition, may store various kinds of information as described above with reference toFIGS.1to21.

In addition to the configurations described above, the PCF1600may further include various interfaces for accesses by an operator. The disclosure does not have special restrictions on such additional configurations.

FIG.28is a block diagram illustrating a UDR/UDM in a wireless communication system according to an embodiment of the disclosure.

Referring toFIG.28, the UDR/UDM1700may perform communication with other network entities of a core network through a network interface1710. For example, the UDR/UDM1700may perform communication with UE1100, gNB1200, UPF1300, AMF1400, SMF1500, PCF1600, NEF1800, and AF1900.

A controller1720may be implemented by at least one processor or/and program for performing the operation of the UDR/UDM1700. For example, the controller1720may perform the operation of the UDR/UDM1700as described above with reference toFIGS.1to21.

A memory1730may store programs and various kinds of control information necessary for the controller1720, and in addition, may store various kinds of information as described above with reference toFIGS.1to21.

In addition to the configurations described above, the UDR/UDM1700may further include various interfaces for accesses by an operator. The disclosure does not have special restrictions on such additional configurations.

FIG.29is a block diagram illustrating an NEF in a wireless communication system according to an embodiment of the disclosure.

Referring toFIG.29, the NEF1800may perform communication with other network entities of a core network through a network interface1810. For example, the NEF1800may perform communication with UE1100, gNB1200, UPF1300, AMF1400, SMF1500, PCF1600, UDR/UDM1700, and AF1900.

A controller1820may be implemented by at least one processor or/and program for performing the operation of the NEF1800. For example, the controller1820may perform the operation of the NEF1800as described above with reference toFIGS.1to21.

A memory1830may store programs and various kinds of control information necessary for the controller1820, and in addition, may store various kinds of information as described above with reference toFIGS.1to21.

In addition to the configurations described above, the NEF1800may further include various interfaces for accesses by an operator. The disclosure does not have special restrictions on such additional configurations.

FIG.30is a block diagram illustrating an AF in a wireless communication system according to an embodiment of the disclosure.

Referring toFIG.30, the AF1900may perform communication with other network entities of a core network through a network interface1910. For example, the AF1900may perform communication with UE1100, gNB1200, UPF1300, AMF1400, SMF1500, PCF1600, UDR/UDM1700, and NEF1800.

A controller1920may be implemented by at least one processor or/and program for performing the operation of the AF1900. For example, the controller1920may perform the operation of the AF1900as described above with reference toFIGS.1to21.

A memory1930may store programs and various kinds of control information necessary for the controller1920, and in addition, may store various kinds of information as described above with reference toFIGS.1to21.

In addition to the constitutions described above, the AF1900may further include various interfaces for accesses by an operator. The disclosure does not have special restrictions on such additional constitutions.

The aspects, features, and advantages of certain embodiments of the disclosure will be more apparent from the following detailed description taken in conjunction with the accompanying drawings. The description of the various embodiments is to be construed as exemplary only and does not describe every possible instance of the disclosure. It should be apparent to those skilled in the art that the following description of various embodiments of the disclosure is provided for illustrative purposes only and not for the purpose of limiting the disclosure as defined by the appended claims and their equivalents. The same reference symbols are used throughout the description to refer to the same parts.

Meanwhile, it is known to those skilled in the art that blocks of a flowchart (or sequence diagram) and a combination of flowcharts may be represented and executed by computer program instructions. These computer program instructions may be loaded on a processor of a general purpose computer, special purpose computer, or programmable data processing equipment. When the loaded program instructions are executed by the processor, they create a means for carrying out functions described in the flowchart. As the computer program instructions may be stored in a computer readable memory that is usable in a specialized computer or a programmable data processing equipment, it is also possible to create articles of manufacture that carry out functions described in the flowchart. As the computer program instructions may be loaded on a computer or a programmable data processing equipment, when executed as processes, they may carry out operations of functions described in the flowchart.

A block of a flowchart may correspond to a module, a segment or a code containing one or more executable instructions implementing one or more logical functions, or to a part thereof. In some cases, functions described by blocks may be executed in an order different from the listed order. For example, two blocks listed in sequence may be executed at the same time or executed in reverse order.

In the description, the word “unit”, “module”, or the like may refer to a software component or hardware component such as a field programmable gate array (FPGA) or application-specific integrated circuit (ASIC) capable of carrying out a function or an operation. However, “unit” or the like is not limited to hardware or software. A unit or the like may be configured so as to reside in an addressable storage medium or to drive one or more processors. Units or the like may refer to software components, object-oriented software components, class components, task components, processes, functions, attributes, procedures, subroutines, program code segments, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, or variables. A function provided by a component and unit may be a combination of smaller components and units, and it may be combined with others to compose large components and units. Components and units may be configured to drive a device or one or more processors in a secure multimedia card. In an embodiment of the disclosure, a unit or module may include one or more processors.