User device and method using user device

Abstract

The embodiments of the present disclosure relate to a method, an apparatus, and a computer-readable medium for communication. When a terminal device performs multicast reception in an inactive or idle state, the terminal device transmits a first message including a preference for the multicast reception in the inactive or idle state to a network device, and receives a second message from the network device indicating the multicast reception in the inactive or idle state and including a multicast setting for the multicast reception. Then, the terminal device performs the multicast reception in the inactive or idle state based on the multicast setting. In this way, the terminal device can enter the inactive or idle state accurately or rationally to receive a multicast service. Furthermore, the terminal device may receive the multicast setting to ensure service continuity during cell reselection.

Description

[Technical field]

[0001] TECHNICAL FIELD Embodiments of the present disclosure relate generally to the field of telecommunications, and more particularly to communication methods, apparatus, and computer storage media for multicast and broadcast services (MBS). [Background technology]

[0002] To enable resource-efficient delivery of MBS, the third generation partnership project (3GPP) developed New Radio (NR) broadcast and multicast in Release 17. In Release 17, multicast is specified only for user equipment (UE) in connected state, which may not fully meet the requirements of some services (e.g., mission-critical services), especially for cells with a large number of UEs. In addition, keeping UEs in connected state all the time is power inefficient. Therefore, it is important to support multicast for UEs in inactive state. However, the solution for multicast reception in inactive state is still incomplete and needs to be further studied. Summary of the Invention [Problem to be solved by the invention]

[0003] In general, the exemplary embodiments of the present disclosure provide a communication method, apparatus, and computer storage medium for multicast reception in an inactive or idle state. [Means for solving the problem]

[0004] In a first aspect, a method of communication is provided, the method including: in accordance with a determination that a terminal device performs multicast reception in an inactive or idle state, sending, in the terminal device, to a network device, a first message including a preference for the multicast reception in the inactive or idle state, receiving from the network device a second message indicating the multicast reception in the inactive or idle state and including a multicast setting for the multicast reception, and performing the multicast reception in the inactive or idle state based on the multicast setting.

[0005] In a second aspect, a method of communication is provided, the method including: receiving, in a terminal device in a connected state, from a network device, a third message including a multicast setting for multicast reception of the terminal device in an inactive or idle state; and performing the multicast reception in the inactive or idle state based on the multicast setting according to a decision of the terminal device to perform the multicast reception in the inactive or idle state.

[0006] In a third aspect, a method of communication is provided, comprising: receiving, in a terminal device, from a network device, a fourth message indicating multicast reception in an inactive or idle state and including a multicast configuration for the multicast reception, the multicast configuration including at least one of an indication of the multicast reception in the inactive or idle state, a list of the terminal device specific multicast settings for cell reselection, or a multicast frequency priority for cell reselection; and performing the multicast reception in the inactive or idle state based on the multicast configuration.

[0007] In a fourth aspect, a method of communication is provided, the method including: receiving, in a network device, a first message from a terminal device, the first message including a preference for multicast reception in an inactive or idle state; and transmitting, to the terminal device, a second message indicating the multicast reception in the inactive or idle state and including a multicast setting for the multicast reception.

[0008] In a fifth aspect, a method of communication is provided, the method including: generating, in a network device, a multicast setting for multicast reception of a terminal device in an inactive or idle state; and transmitting a third message including the multicast setting to the terminal device in a connected state.

[0009] In a sixth aspect, a method of communication is provided, comprising: generating, in a network device, a multicast setting for multicast reception of a terminal device in an inactive or idle state, the multicast setting including at least one of an indication of the multicast reception in the inactive or idle state, a list of the terminal device specific multicast settings for cell reselection, or a multicast frequency priority for cell reselection, and transmitting, to the terminal device, a fourth message indicating the multicast reception of the terminal device in the inactive or idle state and including the multicast setting.

[0010] In a seventh aspect, a terminal device is provided, the terminal device comprising a processor configured to cause the terminal device to execute any one of the methods according to the first to third aspects of the present disclosure.

[0011] In an eighth aspect, there is provided a network device, the network device comprising a processor configured to cause the network device to perform any of the methods of the fourth to sixth aspects of the present disclosure.

[0012] In a ninth aspect, there is provided a computer readable medium having stored thereon instructions which, when executed on at least one processor, cause the at least one processor to perform a method of any of the first to third aspects of the present disclosure.

[0013] In a tenth aspect, there is provided a computer readable medium having stored thereon instructions which, when executed on at least one processor, cause the at least one processor to perform a method of any of the fourth to sixth aspects of the present disclosure.

[0014] Other features of the present disclosure will become readily apparent from the following description. [Brief description of the drawings]

[0015] The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description of several embodiments of the present disclosure in the accompanying drawings.

[0016] [Figure 1] FIG. 1 illustrates an example communication network in which some embodiments of the present disclosure may be implemented.

[0017] [Figure 2A] FIG. 1 is a schematic diagram illustrating a unicast scenario in which some embodiments of the present disclosure can be implemented.

[0018] [Figure 2B] FIG. 1 is a schematic diagram illustrating a multicast scenario in which some embodiments of the present disclosure can be implemented.

[0019] [Diagram 3] FIG. 2 is a schematic diagram illustrating a process of communication for performing multicast reception based on a UE request according to an embodiment of the present disclosure.

[0020] [Figure 4A]FIG. 2 is a schematic diagram illustrating an exemplary data transmission according to an embodiment of the present disclosure.

[0021] [Figure 4B] FIG. 13 is a schematic diagram illustrating another exemplary data transmission according to an embodiment of the present disclosure.

[0022] [Diagram 5] FIG. 2 is a schematic diagram illustrating a process of communication for performing multicast reception based on a network instruction according to an embodiment of the present disclosure.

[0023] [Figure 6] FIG. 2 is a schematic diagram illustrating a process of communication for performing multicast reception based on predefined settings according to an embodiment of the present disclosure.

[0024] [Figure 7A] FIG. 2 is a schematic diagram illustrating a communication process for skipping multicast paging according to an embodiment of the present disclosure.

[0025] [Figure 7B] FIG. 2 is a schematic diagram illustrating a process of communication for entering a connected state for multicast reception according to an embodiment of the present disclosure.

[0026] [Figure 7C] FIG. 11 is a schematic diagram illustrating another communication process for entering a connected state for multicast reception according to an embodiment of the present disclosure.

[0027] [Figure 7D] FIG. 13 is a schematic diagram illustrating yet another communication process for entering a connected state for multicast reception according to an embodiment of the present disclosure.

[0028] [Figure 8] FIG. 2 illustrates an exemplary communication method implemented in a terminal device according to some embodiments of the present disclosure.

[0029] [Figure 9] FIG. 1 illustrates another exemplary communication method implemented in a terminal device in accordance with some embodiments of the present disclosure.

[0030] [Figure 10] FIG. 13 illustrates yet another exemplary communication method implemented in a terminal device in accordance with some embodiments of the present disclosure.

[0031] [Figure 11] FIG. 2 illustrates an example communication method implemented in a network device, according to some embodiments of the present disclosure.

[0032] [Figure 12] FIG. 2 illustrates another exemplary communication method implemented in a network device, in accordance with some embodiments of the present disclosure.

[0033] [Figure 13] FIG. 1 illustrates yet another exemplary communication method implemented in a network device, in accordance with some embodiments of the present disclosure.

[0034] [Figure 14] FIG. 1 is a schematic block diagram of an apparatus suitable for implementing embodiments of the present disclosure.

[0035] In the drawings, the same or similar reference numbers represent the same or similar elements. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0036] The principles of the present disclosure will now be described with reference to some embodiments. It should be understood that these embodiments are provided for illustrative purposes only, to assist those skilled in the art in understanding and implementing the present disclosure, and do not imply any limitations on the scope of the present disclosure. The disclosure described herein can be implemented in various ways different from those described below.

[0037] In the following description and claims, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0038] As used herein, the term "terminal device" refers to any device with wireless or wired communication capabilities. Examples of terminal devices include user equipment (UE), personal computers, desktops, mobile phones, mobile phones, smartphones, personal digital assistants (PDAs), portable computers, tablets, wearable devices, Internet of Things (IoT) devices, Ultra-reliable and Low Latency Communications (URLLC) devices, Internet of Everything (IoE) devices, machine type communication (MTC) devices, vehicle-mounted devices for V2X communications (where X means pedestrians, vehicles, or infrastructure / networks), devices for Integrated Access and Backhaul (IAB), spacecraft or aircraft in High Altitude Platforms (HAPs) including Unmanned Aircraft Systems (UASs) and Non-terrestrial networks (NTNs) including satellites, and Extended Reality (XR) including different types of reality such as Augmented Reality (AR), Mixed Reality (MR), and Virtual Reality (VR). Examples of such devices include, but are not limited to, Reality devices, unmanned aerial vehicles (UAVs), commonly known as drones, which are aircraft that do not require a human pilot, devices on high speed trains (HSTs), imaging devices such as digital cameras, sensors, gaming devices, music storage and playback devices, or Internet devices that enable wireless or wired Internet access and browsing.The "terminal equipment" may further have multicast / broadcast capabilities to support public safety, mission-critical, V2X applications, transparent IPv4 / IPv6 multicast distribution, IPTV, smart TV, wireless services, wireless software distribution, group communication, and IoT applications. It may also incorporate one or more Subscriber Identity Modules (SIMs), known as multi-SIM. The term "terminal equipment" may be used interchangeably with UE, mobile station, subscriber equipment, mobile terminal, user terminal, or wireless device.

[0039] The term "network device" refers to a device capable of providing or hosting a cell or coverage through which terminal devices can communicate. Examples of network devices include, but are not limited to, a Node B (NodeB or NB), an Evolved Node B (eNodeB or eNB), a next generation Node B (gNB), a transmission reception point (TRP), a remote radio unit (RRU), a radio head (RH), a remote radio head (RRH), an IAB node, a low power node such as a femto node, a pico node, a reconfigurable intelligent surface (RIS), etc.

[0040] The terminal device or network device may have the capability of artificial intelligence (AI) or machine learning. Generally, it includes a model trained from a large amount of data collected for a specific function and can be used to predict some information.

[0041] The terminal device or network device may function in multiple frequency ranges, e.g., FR1 (410 MHz-7125 MHz), FR2 (24.25 GHz-71 GHz), higher than 100 GHz, Terahertz (THz), etc. Furthermore, it can function in licensed / unlicensed / shared spectrum. The terminal device may have multiple connections with the network device in Multi-Radio Dual Connectivity (MR-DC) application scenarios. The terminal device or network device can function in full duplex, flexible duplex, and cross-division duplex modes.

[0042] Embodiments of the present disclosure may be implemented in test equipment, such as, for example, a signal generator, a signal analyzer, a spectrum analyzer, a network analyzer, a test terminal equipment, a test network equipment, a channel emulator, and the like.

[0043] In one embodiment, the terminal device may connect to a first network device and a second network device. One of the first network device and the second network device may be a master node, and the other may be a secondary node. The first network device and the second network device may use different radio access technologies (RATs). In one embodiment, the first network device may be a first RAT device, and the second network device may be a second RAT device. In one embodiment, the first RAT device is an eNB, and the second RAT device is a gNB. Information about the different RATs may be transmitted to the terminal device from at least one of the first network device or the second network device. In one embodiment, the first information may be transmitted to the terminal device from the first network device, and the second information may be transmitted to the terminal device from the second network device directly or via the first network device. In one embodiment, information about the configuration of the terminal device configured by the second network device may be transmitted from the second network device via the first network device. Information regarding the reconfiguration of the terminal device configured by the second network device may be transmitted from the second network device directly to the terminal device or via the first network device.

[0044] As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise. The term "comprises" and variations thereof are intended to be open ended, meaning "including, but not limited to." The term "based on" is intended to mean "based at least in part on." The terms "one embodiment" and "embodiment" are intended to mean "at least one embodiment." The term "another embodiment" is intended to mean "at least one other embodiment." Terms such as "first," "second," and the like may refer to different objects or the same object. The following content may include other definitions, both explicit and implicit.

[0045] In some instances, values, processes or devices are referred to as "optimum," "lowest," "highest," "minimum," "maximum," etc. It will be understood that such descriptions are intended to indicate choices among multiple functional alternatives that may be used, and that such choices are not necessarily better, smaller, higher, or more preferred than other choices.

[0046] In the context of this disclosure, the term "MBS" may be used interchangeably with "multicast", "multicast service", "multicast transmission" or "multicast data". The term "multicast reception" may be used interchangeably with "MBS reception". The term "connected state" may be used interchangeably with "RRC_CONNECTED state", the term "idle state" may be used interchangeably with "RRC_IDLE state", and the term "inactive state" may be used interchangeably with "RRC_INACTIVE state".

[0047] Currently, it is proposed to support multicast by UEs in an inactive state, for example, to support point to multi-point (PTM) configuration for UEs receiving multicast in an inactive state, and to study the impact of mobility and state transitions for UEs receiving multicast in an inactive state.

[0048] In view of this, embodiments of the present disclosure provide a solution for transitioning between multicast reception in a connected state and multicast reception in an inactive or idle state.

[0049] In one aspect, according to the determination that the terminal device performs multicast reception in an inactive or idle state, the terminal device transmits a first message including a preference for the multicast reception in the inactive or idle state to a network device. Upon receiving a second message indicating the multicast reception in the inactive or idle state and including a multicast setting for the multicast reception, the terminal device performs the multicast reception in the inactive or idle state based on the multicast setting. In this way, the terminal device can accurately or rationally enter the inactive or idle state to receive a multicast service. Furthermore, the terminal device may receive a multicast setting to ensure service continuity upon cell reselection.

[0050] In another aspect, the terminal device receives a fourth message from a network device indicating multicast reception in an inactive or idle state and including a multicast setting for the multicast reception. The multicast setting includes at least one of an indication of the multicast reception in the inactive or idle state, a list of multicast settings specific to the terminal device for cell reselection, or a multicast frequency priority for cell reselection. The terminal device performs the multicast reception in the inactive or idle state based on the multicast setting. In this way, the terminal device can more flexibly enter the inactive or idle state to receive a multicast service based on a network implementation.

[0051] In yet another aspect, a terminal device in a connected state receives a third message from a network device, the third message including a multicast setting for multicast reception of the terminal device in an inactive or idle state. According to the determination that the terminal device performs the multicast reception in the inactive or idle state, the terminal device performs the multicast reception in the inactive or idle state based on the multicast setting. In this way, the terminal device can more flexibly and quickly enter the inactive or idle state to receive a multicast service based on a predefined multicast setting.

[0052] The principles and embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. Communication Network Example

[0053] FIG 1 is a schematic diagram of an example communication network 100 in which embodiments of the present disclosure can be implemented. As shown in FIG 1, communication network 100 may include terminal device 110, network device 120, and network device 130. In some embodiments, network device 120 may provide a serving cell (also referred to herein as a cell) 121 for serving one or more terminal devices. Network device 130 may also provide a cell 131 for serving one or more terminal devices. In this example, terminal device 110 is shown located within cell 121 and served by network device 120.

[0054] In some embodiments, as terminal device 110 moves, terminal device 110 may reselect from cell 121 to cell 131 and then be served by network device 130. In some embodiments, terminal device 110 may perform this cell reselection in an inactive or idle state.

[0055] It should be understood that the number of devices or cells in Figure 1 is given for illustrative purposes and does not imply any limitations to the present disclosure. Communications network 100 may include any suitable number of network devices and / or terminal devices and / or cells suitable for implementing embodiments of the present disclosure.

[0056] As shown in Figure 1, terminal device 110 may communicate with network devices 120 and 130 via channels, such as wireless communication channels. Communications in communication network 100 may conform to any suitable standard, including, but not limited to, Global System for Mobile Communications (GSM), Long Term Evolution (LTE), LTE-Evolution, LTE-Advanced (LTE-A), New Radio (NR), Wideband Code Division Multiple Access (WCDMA), Code Division Multiple Access (CDMA), GSM EDGE Radio Access Network (GERAN), Machine Type Communication (MTC), and the like. Embodiments of the present disclosure may be performed according to any generation of communication protocols now known or developed in the future. Examples of communication protocols include, but are not limited to, first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, fifth generation (5G) communication protocols, 5.5G, 5G-Advanced networks, or sixth generation (6G) networks.

[0057] In some embodiments where terminal device 110 is served by network device 120, terminal device 110 may receive unicast services from network device 120. FIG. 2A is a schematic diagram illustrating a unicast scenario 200A in which some embodiments of the present disclosure can be implemented. As shown in FIG. 2A, base station 210 may transmit downlink control information (DCI) on physical downlink control channel (PDCCH) 201 with a cell-radio network temporary identifier (C-RNTI) for UE1. Thus, UE1 may be scheduled to receive data (e.g., a video stream) on physical downlink shared channel (PDSCH) 202 in unicast. Similarly, base station 210 may transmit DCI on PDCCH 203 with a C-RNTI for UE2 to schedule UE2 to receive data on PDSCH 204 in unicast. The base station 210 may send DCI on the PDCCH 205 with the C-RNTI for UE3 and schedule UE3 to receive data on the PDSCH 206 in unicast.

[0058] In some embodiments in which terminal device 110 is served by network device 120, terminal device 110 may receive a multicast service from network device 120. FIG. 2B is a schematic diagram illustrating a multicast scenario 200B in which some embodiments of the present disclosure can be implemented. As shown in FIG. 2B, base station 210 may transmit DCI on PDCCH 207 with a group-radio network temporary identifier (G-RNTI) for a set of UEs 220. Thus, the set of UEs 220 may be scheduled to receive data on PDSCH 208 in a multicast, i.e., to receive data simultaneously.

[0059] That is, in the case of a multicast communication service, the same service and the same specific content data are simultaneously provided to a dedicated set of UEs (i.e., not all UEs in a multicast service area are allowed to receive the data). The multicast communication service is delivered to the UEs using a multicast session. The UEs can receive the multicast communication service in a connected state using mechanisms such as point-to-point (PTP) and / or PTM delivery.

[0060] In some embodiments, terminal device 110 may receive data of MBS multi-session only in connected state. When terminal device 110 that has joined a multicast session is in connected state and the multicast session starts, network device 120 may send a radio resource control (RRC) reconfiguration message with the associated MBS configuration (also referred to as multicast configuration) for the multicast session to terminal device 110. In this case, a separate session activation notification for terminal device 110 is not required.

[0061] In some embodiments, if there is no data to be sent to terminal device 110 for a multicast session, network device 120 may cause terminal device 110 to enter an inactive or idle state. In some embodiments, if a multicast session has already been activated by the core network (CN) or if network device 120 has multicast session data to distribute, network device 120 may notify terminal device 110 that is in an inactive or idle state using a group notification mechanism (i.e., multicast paging).

[0062] It has been proposed that the terminal device may enter an inactive or idle state and continue to receive the multicast service. However, it is still unclear how to trigger the terminal device to enter an inactive or idle state. It is also unclear how a terminal device in an inactive or idle state acquires the multicast configuration and monitors multicast paging when a cell reselection occurs.

[0063] In view of this, the embodiments of the present disclosure provide a solution for multicast reception in an inactive or idle state, which will be described in detail with reference to Figures 3 to 7D. Example of entering inactive or idle state based on UE request

[0064] In this embodiment, the terminal device can enter an inactive or idle state based on its request (i.e., a UE request) and continue receiving the multicast service.

[0065] FIG. 3 is a schematic diagram illustrating a communication process 300 according to an embodiment of the present disclosure. For illustrative purposes, the process 300 will be described with reference to FIG. 1. The process 300 may involve a terminal device 110 and a network device 120 as shown in FIG. 1. It should be understood that the steps and the order of steps in FIG. 3 are merely for illustration and not for limitation. For example, the order of steps may be changed. Some of the steps may be omitted, or any other suitable additional steps may be added. Assume that the terminal device 110 is served by the network device 120 and the terminal device 110 is initially in a connected state.

[0066] As shown in FIG. 3, network device 120 may send an inquiry to terminal device 110 about the capabilities of terminal device 110 (310). For example, network device 120 may send a UECapabilityEnquiry message or any other appropriate message. In response to the inquiry, terminal device 110 may send to network device 120 the capabilities of terminal device 110 for multicast reception in an inactive or idle state (320). For example, terminal device 110 may send a UECapabilityInformation message or any other appropriate message. In some embodiments, the capabilities of terminal device 110 may indicate whether it supports multicast reception in an inactive or idle state. It should be understood that the capabilities of terminal device 110 may also include any other appropriate information, and the disclosure is not limited in this respect.

[0067] 3, the terminal device 110 may determine whether to perform multicast reception in an inactive or idle state (330). In some embodiments, the terminal device 110 may determine whether to perform multicast reception in the inactive or idle state based on a timer (also referred to herein as a first timer or a multicast timer).

[0068] In some embodiments, the network device 120 may configure a multicast timer for the terminal device 110 via RRC dedicated signaling. In some embodiments, the network device 120 may configure the multicast timer in a system information block (SIB). In some embodiments, the multicast timer may be predefined.

[0069] In some embodiments, if multicast data is received and the multicast timer is not running, terminal device 110 may start a multicast timer 331. For example, if any medium access control (MAC) entity receives a MAC service data unit (SDU) for an MBS traffic channel (MTCH) logical channel for a multicast service and the multicast timer is not running, terminal device 110 may start a multicast timer.

[0070] In some embodiments, terminal device 110 may restart the multicast timer if unicast data is received (332). For example, terminal device 110 may restart the multicast timer if any MAC entity receives a MAC SDU for a dedicated traffic channel (DTCH), dedicated control channel (DCCH), or common control channel (CCCH) logical channel. In some alternative or additional embodiments, terminal device 110 may restart the multicast timer if unicast data is transmitted. For example, terminal device 110 may restart the multicast timer if any MAC entity transmits a MAC SDU for a DTCH, DCCH, or CCCH logical channel.

[0071] In some embodiments, if the multicast timer expires, terminal device 110 may determine that terminal device 110 performs multicast reception in an inactive or idle state (333). For example, if the multicast timer expires, the MAC layer of terminal device 110 may indicate the expiration of the multicast timer to a higher layer (e.g., the RRC layer) of terminal device 110. In some alternative embodiments, if terminal device 110 enters an inactive or idle state to perform multicast reception and the multicast timer is not running, terminal device 110 may determine that terminal device 110 performs multicast reception in an inactive or idle state (333').

[0072] 3, when it is determined that the terminal device 110 performs multicast reception in an inactive or idle state, the terminal device 110 may transmit a message (for convenience, also referred to herein as a first message) including a preference for multicast reception in an inactive or idle state to the network device 120 (340). For example, the first message may be a UE assistance information (UAI) message. It should be understood that any other suitable message is also possible.

[0073] For example, upon receiving a multicast timer expiration from a lower layer (e.g., MAC layer) of the terminal device 110 in a connected state, the terminal device 110 may initiate sending a UAI message in response to multicast reception within an inactive or idle state request to provide a preference report, which will inform the network device 120 that the terminal device 110 wishes to receive the multicast service in an inactive or idle state.

[0074] As another example, if the terminal device 110 has a preference for multicast reception in the inactive or idle state, and the terminal device 110 has not previously sent a UAI message with a multicast preference for this cell, and the multicast timer is not running, the terminal device 110 may start sending a UAI message according to the multicast reception in the inactive or idle state request to provide a preference report. This preference report will inform the network device 120 that the terminal device 110 wants to receive the multicast service in the inactive or idle state.

[0075] 3, the terminal device 110 may receive (350) from the network device 120 a message (also referred to herein as a second message for convenience) indicating multicast reception in an inactive or idle state and including a multicast setting for the multicast reception. For example, the second message may be an RRC release message. It should be understood that any other suitable message is also possible.

[0076] In some embodiments, the multicast configuration may include an indication of the multicast reception in the inactive or idle state, for example, if the indication is set to true, the terminal device 110 is indicated to receive the multicast service in the inactive or idle state.

[0077] In some embodiments, the multicast configuration may include a list of multicast configurations for cell reselection. For example, the list of multicast configurations may include C-RNTIs for different cells. As another example, the list of multicast configurations may include packet data convergence protocol (PDCP) or radio link control (RLC) or MAC or physical (PHY) or bandwidth part (BWP) configurations for different cells. For example, the MAC configuration list may include G-RNTIs for different cells.

[0078] In some embodiments, the multicast configuration may include a multicast frequency priority for cell reselection. In some embodiments, the multicast configuration may include a multicast allowed cell list indicating a first set of cells for which the multicast configuration is allowed for multicast reception. In some embodiments, the multicast configuration may include a neighbor cell list indicating a second set of cells that provide a multicast service that the terminal device is receiving. It should be understood that the multicast configuration may include any other suitable information.

[0079] In some embodiments, upon sending the first message (e.g., UAI), the terminal device 110 may start a timer (also referred to herein as a second timer or RRC release timer for convenience). The RRC release timer ensures a valid time interval for the RRC release message. In some embodiments, the terminal device 110 may further disable a multicast timer. That is, the terminal device 110 may stop evaluating the multicast timer and the UAI procedure.

[0080] In some embodiments, if the RRC release timer expires and terminal device 110 has not yet received a second message (e.g., an RRC release message), terminal device 110 may enable the multicast timer, i.e., terminal device 110 may re-trigger the UAI and therefore re-evaluate the multicast timer. In some embodiments, upon receiving the second message, terminal device 110 may stop the RRC release timer (if set).

[0081] Upon receiving the second message, the terminal device 110 may perform multicast reception in an inactive or idle state based on the multicast setting (360). For example, the terminal device may enter an inactive or idle state (361) and receive the multicast service in an inactive or idle state (362).

[0082] In some embodiments, if the multicast settings include an instruction for multicast reception in the inactive or idle state, the terminal device 110 may continue to receive multicast data in the inactive or idle state, i.e., the terminal device 110 may apply the multicast settings used in the connected state to receive multicast data in the inactive or idle state without releasing them.

[0083] In some embodiments, the multicast settings include a list of multicast settings for cell reselection, and when the terminal device 110 reselects to a cell (for convenience, also referred to as the first cell in this specification), the terminal device 110 may apply the multicast settings for the first cell from the list of multicast settings.

[0084] In some embodiments, if the multicast settings include a multicast frequency priority for cell reselection, the terminal device 110 may store the multicast frequency priority and perform the cell reselection based on the multicast frequency priority when the terminal device 110 enters an inactive or idle state.

[0085] In some embodiments, if the multicast settings include a multicast allowed cell list, the terminal device 110 may apply the multicast settings to a cell in the multicast allowed cell list (for convenience, also referred to as a second cell in this specification) when the terminal device 110 reselects to the second cell.

[0086] In some embodiments, if the multicast configuration includes a neighbor cell list, terminal device 110 may apply and store the neighbor cell list for multicast reception.

[0087] FIG. 4A is a schematic diagram 400A illustrating an example data transmission according to an embodiment of the present disclosure. As shown in FIG. 4A, at timing T1, the network device 120 may configure the terminal device 110 in a connected state to have a multicast timer (Mtimer) of 10 seconds and an RRC release timer (Rtimer) of 5 seconds. Upon receiving multicast data from the network device 120 at timing T2, the terminal device 110 may start the multicast timer. While the multicast timer is running, the terminal device 110 may further receive multicast data at timing T3. In this case, the multicast timer continues to run. While the multicast timer is running, the terminal device 110 may receive unicast data at timing T4. In this case, the multicast timer is restarted. When the multicast timer expires at timing T5, the terminal device 110 may send a UAI to inform the network device 120 of its preference for multicast reception in an inactive or idle state. Upon sending the UAI, the terminal device 110 may start the RRC release timer and disable the multicast timer.

[0088] As shown in Fig. 4A, while the RRC release timer is running, the terminal device 110 does not receive an RRC release message. When the RRC release timer expires, the terminal device 110 may re-enable the multicast timer and re-evaluate whether to enter an inactive state or an idle state to receive the multicast service. In this example, it can be seen that the terminal device 110 is always in a connected state.

[0089] FIG. 4B is a schematic diagram 400B illustrating another exemplary data transmission according to an embodiment of the present disclosure. As shown in FIG. 4B, at timing T6, the network device 120 may configure the terminal device 110 in a connected state to have a multicast timer (Mtimer) of 10 seconds and an RRC release timer (Rtimer) of 5 seconds. Upon receiving multicast data from the network device 120 at timing T6, the terminal device 110 may start the multicast timer. While the multicast timer is running, the terminal device 110 may further receive multicast data at timing T7. In this case, the multicast timer continues to run. While the multicast timer is running, the terminal device 110 may receive unicast data at timing T8. In this case, the multicast timer is restarted. When the multicast timer expires at timing T9, the terminal device 110 may send a UAI to inform the network device 120 of its preference for multicast reception in an inactive or idle state. Upon sending the UAI, the terminal device 110 may start the RRC release timer and disable the multicast timer.

[0090] As shown in Figure 4B, while the RRC release timer is running, the terminal device 110 receives an RRC release message indicating multicast reception in an inactive or idle state at timing T10. Upon receiving the RRC release message, the terminal device 110 may stop the RRC release timer and enter an inactive or idle state to continue receiving the multicast service. It should be understood that Figures 4A and 4B are merely examples and are not intended to limit the present disclosure.

[0091] In this way, the terminal device can accurately or rationally enter an inactive or idle state to receive the multicast service. Furthermore, the terminal device may receive a multicast configuration to ensure service continuity upon cell reselection. Example of entering inactive or idle state based on network indication

[0092] In this embodiment, the terminal device may enter an inactive or idle state based on an instruction from the network and continue receiving the multicast service.

[0093] FIG. 5 is a schematic diagram illustrating a communication process 500 according to an embodiment of the present disclosure. For illustrative purposes, the process 500 is described with reference to FIG. 1. The process 500 may involve a terminal device 110 and a network device 120 as shown in FIG. 1. It should be understood that the steps and the order of steps in FIG. 5 are merely for illustration and not for limitation. For example, the order of steps may be changed. Some of the steps may be omitted, or any other suitable additional steps may be added. Assume that the terminal device 110 is served by the network device 120 and the terminal device 110 is initially in a connected state.

[0094] As shown in FIG. 5, network device 120 may send an inquiry to terminal device 110 about the capabilities of terminal device 110 (510). For example, network device 120 may send a UECapabilityEnquiry message or any other appropriate message. In response to the inquiry, terminal device 110 may send to network device 120 the capabilities of terminal device 110 for multicast reception in an inactive or idle state (520). For example, terminal device 110 may send a UECapabilityInformation message or any other appropriate message. In some embodiments, the capabilities of terminal device 110 may indicate whether it supports multicast reception in an inactive or idle state. It should be understood that the capabilities of terminal device 110 may also include any other appropriate information, and the disclosure is not limited in this respect.

[0095] 5, terminal device 110 may receive a message (also referred to herein as a fourth message for convenience) from network device 120 indicating multicast reception in an inactive or idle state and including a multicast setting for the multicast reception (530). For example, the fourth message may be an RRC release message. It should be understood that any other suitable message is possible and the disclosure is not limited in this respect. In some embodiments, terminal device 110 may store and apply the multicast setting.

[0096] In some embodiments, the multicast configuration may include an indication of the multicast reception in the inactive or idle state, for example, if the indication is set to true, the terminal device 110 is indicated to receive the multicast service in the inactive or idle state.

[0097] In some embodiments, the multicast configuration may include a list of multicast configurations for cell reselection. For example, the list of multicast configurations may include C-RNTIs for different cells. As another example, the list of multicast configurations may include configurations for PDCP or RLC or MAC or PHY or BWP for different cells. For example, the MAC configuration list may include G-RNTIs for different cells.

[0098] In some embodiments, the multicast settings may include a multicast frequency preference for cell reselection.

[0099] It should be understood that the multicast configuration may include any other suitable information. In some embodiments, the multicast configuration may further include a multicast allowed cell list indicating a first set of cells in which the multicast configuration is permitted for multicast reception. In some embodiments, the multicast configuration may further include a neighbor cell list indicating a second set of cells providing a multicast service that the terminal device is receiving.

[0100] Upon receiving the fourth message, the terminal device 110 may perform multicast reception in an inactive or idle state based on the multicast setting (540). For example, the terminal device 110 may enter an inactive or idle state (541) and receive the multicast service in the inactive or idle state (542).

[0101] In some embodiments, if the multicast settings include an instruction for multicast reception in the inactive or idle state, the terminal device 110 may continue to receive multicast data in the inactive or idle state, i.e., the terminal device 110 may apply the multicast settings used in the connected state to receive multicast data in the inactive or idle state without releasing them.

[0102] In some embodiments, the multicast settings include a list of multicast settings for cell reselection, and when the terminal device 110 reselects to a cell, the terminal device 110 may apply the multicast settings for the cell from the list of multicast settings.

[0103] In some embodiments, if the multicast settings include a multicast frequency priority for cell reselection, the terminal device 110 may store the multicast frequency priority and perform the cell reselection based on the multicast frequency priority when the terminal device 110 enters an inactive or idle state.

[0104] In some embodiments, if the multicast configuration includes a multicast allowed cell list, terminal device 110 may apply the multicast configuration to a cell in the multicast allowed cell list if terminal device 110 reselects to the cell.

[0105] In some embodiments, if the multicast configuration includes a neighbor cell list, terminal device 110 may apply and store the neighbor cell list for multicast reception.

[0106] Thus, the terminal device can more flexibly enter an inactive or idle state to receive multicast services based on the network implementation. Example of entering inactive or idle state based on predefined settings

[0107] In this embodiment, the terminal device may enter an inactive or idle state based on predefined settings and continue receiving the multicast service.

[0108] FIG. 6 is a schematic diagram illustrating a communication process 600 according to an embodiment of the present disclosure. For illustrative purposes, the process 600 is described with reference to FIG. 1. The process 600 may involve a terminal device 110 and a network device 120 as shown in FIG. 1. It should be understood that the steps and the order of steps in FIG. 6 are merely for illustration and not for limitation. For example, the order of steps may be changed. Some of the steps may be omitted, or any other suitable additional steps may be added. Assume that the terminal device 110 is served by the network device 120 and the terminal device 110 is initially in a connected state.

[0109] As shown in FIG. 6, network device 120 may send an inquiry to terminal device 110 about the capabilities of terminal device 110 (610). For example, network device 120 may send a UECapabilityEnquiry message or any other appropriate message. In response to the inquiry, terminal device 110 may send terminal device 110's capabilities for multicast reception in an inactive or idle state to network device 120 (620). For example, terminal device 110 may send a UECapabilityInformation message or any other appropriate message. In some embodiments, the capabilities of terminal device 110 may indicate whether it supports multicast reception in an inactive or idle state. It should be understood that the capabilities of terminal device 110 may also include any other appropriate information, and the disclosure is not limited in this respect.

[0110] Continuing to refer to FIG. 6, the terminal device 110 in a connected state may receive a message (for convenience, also referred to herein as a third message) including a multicast setting for multicast reception of the terminal device 110 in an inactive or idle state from the network device 120 (630). In some embodiments, the third message may be an RRC dedicated signaling. For example, the third message may be an RRC reconfiguration message, an RRC setup message, or an RRC resume message. It should be understood that any other suitable message is also possible, and the present disclosure is not limited in this respect. Thus, the multicast setting for multicast reception in an inactive or idle state may be provided to the terminal device in advance.

[0111] In some embodiments, the multicast configuration may include an indication of the multicast reception in the inactive or idle state, for example, if the indication is set to true, the terminal device 110 is indicated to receive the multicast service in the inactive or idle state.

[0112] In some embodiments, the multicast configuration may include a list of multicast configurations for cell reselection. For example, the list of multicast configurations may include C-RNTIs for different cells. As another example, the list of multicast configurations may include packet data convergence protocol (PDCP) or radio link control (RLC) or MAC or physical (PHY) or bandwidth part (BWP) configurations for different cells. For example, the MAC configuration list may include G-RNTIs for different cells.

[0113] In some embodiments, the multicast configuration may include a multicast frequency priority for cell reselection. In some embodiments, the multicast configuration may include a multicast allowed cell list indicating a first set of cells for which the multicast configuration is permitted for multicast reception. In some embodiments, the multicast configuration may further include a neighbor cell list indicating a second set of cells that provide a multicast service that the terminal device is receiving. It should be understood that the multicast configuration may include any other suitable information.

[0114] 6, terminal device 110 may determine whether to perform multicast reception in an inactive or idle state (640). In some embodiments, terminal device 110 may determine whether to perform multicast reception in the inactive or idle state based on the multicast timer.

[0115] In some embodiments, the network device 120 may configure a multicast timer for the terminal device 110 via RRC dedicated signaling. In some embodiments, the network device 120 may configure the multicast timer in the SIB. In some embodiments, the multicast timer may be predefined.

[0116] In some embodiments, if multicast data is received and the multicast timer is not running, the terminal device 110 may start a multicast timer (641). For example, if any MAC entity receives a MAC SDU for an MTCH logical channel for a multicast service and the multicast timer is not running, the terminal device 110 may start a multicast timer.

[0117] In some embodiments, terminal device 110 may restart the multicast timer if unicast data is received (642). For example, terminal device 110 may restart the multicast timer if any MAC entity receives a MAC SDU for a DTCH, DCCH, or CCCH logical channel. In some alternative or additional embodiments, terminal device 110 may restart the multicast timer if unicast data is transmitted. For example, terminal device 110 may restart the multicast timer if any MAC entity transmits a MAC SDU for a DTCH, DCCH, or CCCH logical channel.

[0118] In some embodiments, if the multicast timer expires, terminal device 110 may determine that terminal device 110 performs multicast reception in an inactive or idle state (643). For example, if the multicast timer expires, the MAC layer of terminal device 110 may indicate the expiration of the multicast timer to a higher layer (e.g., the RRC layer) of terminal device 110. In some alternative embodiments, if terminal device 110 enters an inactive or idle state to perform multicast reception and the multicast timer is not running, terminal device 110 may determine that terminal device 110 performs multicast reception in an inactive or idle state (643').

[0119] When it is determined that the terminal device 110 performs multicast reception in the inactive or idle state, the terminal device 110 may perform multicast reception in the inactive or idle state based on the multicast setting (650). For example, the terminal device may enter the inactive or idle state (651) and receive the multicast service in the inactive or idle state (652).

[0120] In some embodiments, if the multicast settings include an instruction for multicast reception in the inactive or idle state, the terminal device 110 may continue to receive multicast data in the inactive or idle state, i.e., the terminal device 110 may apply the multicast settings used in the connected state to receive multicast data in the inactive or idle state without releasing them.

[0121] In some embodiments, the multicast settings include a list of multicast settings for cell reselection, and when terminal device 110 reselects to a cell (for convenience, also referred to as the first cell in this specification), terminal device 110 may apply the multicast settings for the first cell in the list of multicast settings.

[0122] In some embodiments, if the multicast settings include a multicast frequency priority for cell reselection, the terminal device 110 may store the multicast frequency priority and perform the cell reselection based on the multicast frequency priority when the terminal device 110 enters an inactive or idle state.

[0123] In some embodiments, if the multicast settings include a multicast allowed cell list, the terminal device 110 may apply the multicast settings to a cell in the multicast allowed cell list (for convenience, also referred to as a second cell in this specification) when the terminal device 110 reselects to the second cell.

[0124] In some embodiments, if the multicast configuration includes a neighbor cell list, terminal device 110 may apply and store the neighbor cell list for multicast reception.

[0125] In this way, the terminal device can more flexibly and quickly enter an inactive or idle state to receive the multicast service based on the predefined multicast settings. Example of returning to a connected state

[0126] Conventionally, when a terminal device receives a multicast service in an inactive or idle state, the terminal device will monitor multicast paging in the inactive or idle state. If the terminal device is indicated by multicast paging to receive the multicast service in a connected state, the terminal device must perform a random access procedure to fall back to the connected state.

[0127] In view of this, embodiments of the present disclosure provide a solution for determining whether to enter a connected state for multicast reception to solve these and other potential problems.

[0128] FIG. 7A is a schematic diagram illustrating a process 700A of communication for skipping multicast paging according to an embodiment of the present disclosure. For illustrative purposes, the process 700A is described with reference to FIG. 1. The process 700A may involve a terminal device 110 and a network device 120 as shown in FIG. 1. It should be understood that the steps and the order of steps in FIG. 7A are merely for illustration and not for limitation. For example, the order of steps may be changed. Some of the steps may be omitted, or any other suitable additional steps may be added. Assume that the terminal device 110 is served by the network device 120 and the terminal device 110 is in an inactive or idle state.

[0129] 7A, the network device 120 may send (710) a paging message to the terminal device 110. The paging message indicates multicast reception in a connected state.

[0130] Upon receiving the paging message, the terminal device 110 may determine whether the terminal device 110 is receiving a multicast session in an inactive or idle state and whether the multicast session is a multicast session in which the terminal device 110 in the paging message is interested. For example, the terminal device 110 may determine whether the terminal device 110 has already participated in an MBS session indicated by a temporary mobile group identity (TMGI) included in a paging group list of the paging message and is receiving the MBS session in an inactive or idle state. If the terminal device 110 is participating in an MBS session indicated by a TMGI included in a paging group list and is receiving the MBS session, the terminal device 110 may determine that the terminal device 110 is receiving a multicast session in which the terminal device 110 in the paging message is interested.

[0131] If the terminal device 110 is receiving a multicast session in which the terminal device 110 is interested in the paging message, the terminal device 110 may skip the paging message (712). That is, the terminal device 110 continues multicast reception in an inactive or idle state. For example, if the terminal device 110 in an inactive or idle state is receiving an MBS session indicated by a TMGI included in a paging group list, the terminal device 110 may ignore the paging group list in the paging message.

[0132] If the terminal device 110 does not receive the multicast session in which the terminal device 110 is interested in the paging message, the terminal device 110 may perform multicast reception in the connected state (713). That is, the terminal device 110 may enter the connected state and receive the multicast session. For example, if the terminal device 110 has already participated in the MBS session indicated by the TMGI included in the paging group list, but has not received the MBS session, the terminal device 110 may forward the TMGI to the upper layer. Thus, the terminal device in the idle state may perform a random access procedure to enter the connected state for multicast reception. As another example, if the terminal device 110 in the inactive state has already participated in the MBS session indicated by the TMGI included in the paging group list, and has not received the MBS session, the terminal device 110 may initiate an RRC connection resumption procedure.

[0133] In this way, the terminal device may avoid such unnecessary paging messages in order to conserve power. It should be understood that the solution of Figure 7A may be used individually or in combination with any one of the solutions of Figures 3, 5 and 6.

[0134] The embodiments of the present disclosure also provide a solution for entering a connected state for multicast reception to solve the above and other potential problems. FIG. 7B is a schematic diagram illustrating a process 700B of communication for entering a connected state for multicast reception according to an embodiment of the present disclosure. For illustrative purposes, the process 700B is described with reference to FIG. 1. The process 700B may involve the terminal device 110 and the network device 120 as shown in FIG. 1. It should be understood that the steps and the order of the steps in FIG. 7B are merely for illustration and not for limitation. For example, the order of the steps may be changed. Some of the steps may be omitted, or any other suitable additional steps may be added. Assume that the terminal device 110 is served by the network device 120 and the terminal device 110 is in an inactive or idle state.

[0135] 7B, the network device 120 may send (720) a paging message to the terminal device 110. The paging message indicates multicast reception in a connected state. The paging message includes another multicast setting for multicast reception in a connected state.

[0136] In some embodiments, the other multicast configuration may include an indication indicating the multicast reception in the connected state. In some embodiments, the other multicast configuration may include a multicast configuration for the connected state. In some embodiments, the multicast configuration for the connected state may include a list of multicast configurations for cell reselection, a multicast frequency priority for cell reselection, a multicast allowed cell list indicating a set of cells for which the multicast configuration is allowed for the multicast reception, or a neighbor cell list indicating a set of cells providing a multicast service that the terminal device is receiving. It should be understood that the multicast configuration for the connected state may also include any other suitable information, and the disclosure is not limited in this respect.

[0137] Upon receiving the paging message, terminal device 110 may perform multicast reception in the connected state based on the other multicast settings (721). In some embodiments, if the other multicast settings include an indication of multicast reception in the connected state, terminal device 110 may enter the connected state and perform multicast reception in the connected state based on the multicast settings used in the inactive or idle state.

[0138] Thus, when entering a connected state, the terminal device 110 may directly use the other multicast configuration immediately without waiting for RRC reconfiguration from the network device 120. Thus, a lower data reception delay can be achieved. It should be understood that the solution of Fig. 7B may be used individually or in combination with any one of the solutions of Figs. 3, 5 and 6.

[0139] In some scenarios, a terminal device in an inactive or idle state may be in a poor quality signal channel. In this case, the terminal device may have some problems with multicast scheduling, but there is no feedback mechanism. In view of this, the embodiments of the present disclosure provide a solution for entering a connected state for multicast reception to solve this problem and other potential problems.

[0140] FIG. 7C is a schematic diagram illustrating another communication process 700C for entering a connected state for multicast reception according to an embodiment of the present disclosure. For illustrative purposes, the process 700C is described with reference to FIG. 1. The process 700C may involve the terminal device 110 and the network device 120 as shown in FIG. 1. It should be understood that the steps and the order of the steps in FIG. 7C are merely for illustration and not for limitation. For example, the order of the steps may be changed. Some of the steps may be omitted, or any other suitable additional steps may be added. Assume that the terminal device 110 is served by the network device 120 and the terminal device 110 is in an inactive or idle state.

[0141] As shown in FIG. 7C, terminal device 110 may determine whether the signal quality of the channel between terminal device 110 and network device 120 is below a threshold quality (730).

[0142] In some embodiments, the terminal device 110 may determine whether a reference signal receive power (RSRP) on a channel is below a threshold power. If the RSRP on a channel is below a threshold power, the terminal device 110 may determine that the signal quality is below a threshold quality. In some embodiments, the threshold power may be set by system information. In some embodiments, the threshold power may be set by RRC dedicated signaling. In some embodiments, the threshold power may be predefined. Alternatively, the terminal device 110 may determine whether a reference signal receive quality (RSRQ) on a channel is below a threshold. If the RSRQ on a channel is below a threshold, the terminal device 110 may determine that the signal quality is below a threshold quality. In some embodiments, the threshold may be set by system information. In some embodiments, the threshold may be set by RRC dedicated signaling. In some embodiments, the threshold may be predefined.

[0143] In some alternative embodiments, the terminal device 110 may determine whether the signal reception level (e.g., Srxlev) is below a threshold level. If the signal reception level is below the threshold level, the terminal device 110 may determine that the signal quality is below the threshold quality. In other words, the measurement rules for cell reselection may be reused.

[0144] In some alternative embodiments, the terminal device 110 may determine whether a non-at-cell-edge criterion is met. If the non-at-cell-edge criterion is not met, the terminal device 110 may determine that the signal quality is below a threshold quality. In other words, the non-at-cell-edge criterion may be reused.

[0145] Continuing to refer to FIG. 7C, if the signal quality is below the threshold quality, the terminal device 110 may initiate random access (740) to enter into a connection state with the network device 120.

[0146] Thus, the network can change the settings of the connected terminal device to ensure a better quality of service. It should be understood that the solution of Fig. 7C may be used individually or in combination with any one of the solutions of Figs. 3, 5 and 6.

[0147] In some scenarios, a terminal device in an inactive or idle state may reselect to a cell. In this case, scheduling for multicast reception in an inactive or idle state may be problematic, and how to obtain multicast configuration for a cell also needs to be resolved. To solve these and other potential problems, embodiments of the present disclosure provide a solution for entering a connected state for multicast reception.

[0148] FIG. 7D is a schematic diagram illustrating yet another communication process 700D for entering a connected state for multicast reception according to an embodiment of the present disclosure. For illustrative purposes, the process 700D is described with reference to FIG. 1. The process 700D may involve the terminal device 110 and the network device 120 as shown in FIG. 1. It should be understood that the steps and the order of steps in FIG. 7D are merely for illustration and not for limitation. For example, the order of steps may be changed. Some of the steps may be omitted, or any other suitable additional steps may be added. Assume that the terminal device 110 is served by the network device 120 and the terminal device 110 is in an inactive or idle state.

[0149] 7D, the terminal device 110 may determine (740) whether cell reselection to a cell (also referred to herein as a third cell for convenience, e.g., cell 131 of the network device 130) has occurred. If cell reselection has occurred, the terminal device 110 may initiate (741) random access to the cell 131 for multicast reception.

[0150] In some embodiments, if terminal device 110 is receiving a multicast service but is not configured to have multicast settings for cell 131, terminal device 110 may initiate random access for multicast reception.

[0151] In some embodiments, when terminal device 110 is receiving a multicast service, and the neighboring cell information stored for multicast includes cell 131, and terminal device 110 does not have a multicast setting for cell 131, terminal device 110 may initiate random access for multicast reception.

[0152] In some embodiments, when the terminal device 110 is receiving a multicast service and the terminal device 110 does not have a multicast configuration for the cell 131, the terminal device 110 may determine whether one of the multicast sessions that the terminal device 110 is receiving matches a multicast session indicated in the list of multicast sessions broadcast by the cell 131. If one of the multicast sessions that the terminal device is receiving matches a multicast session indicated in the list, the terminal device 110 may initiate random access for multicast reception. In this embodiment, a list of multicast sessions may be broadcast in the system information by the cell 131. This list provides which multicast sessions are running in the cell 131. In some embodiments, the list may indicate the TMGI associated with each of the multicast sessions.

[0153] Thus, a mechanism for multicast reception during cell reselection is defined, so that it is possible to ensure that the terminal device receives the multicast service even if a cell reselection occurs. It should be understood that the solution of Figure 7D may be used individually or in combination with any one of the solutions of Figures 3, 5 and 6. Example of the method

[0154] Corresponding to the above process, the embodiments of the present disclosure provide communication methods implemented in a terminal device and a network device, which are described below with reference to Figures 8 and 13.

[0155] 8 illustrates an example communication method 800 implemented in a terminal device, according to some embodiments of the present disclosure. For example, the method 800 may be performed in a terminal device 110 as shown in FIG. For purposes of explanation, the method 800 will be described below with reference to FIG. 1. It should be understood that the method 800 may include additional blocks not shown and / or omit some blocks that are shown, and that the scope of the present disclosure is not limited in this respect.

[0156] In block 810, the terminal device 110 determines whether the terminal device 110 performs multicast reception in an inactive or idle state.

[0157] In some embodiments, when multicast data is received and the first timer is not running, the terminal device 110 may start the first timer. When unicast data is received or transmitted, the terminal device 110 may restart the first timer. In some embodiments, when the first timer expires, the terminal device 110 may determine that the terminal device 110 performs multicast reception in an inactive or idle state. Alternatively, when the terminal device 110 enters an inactive or idle state to perform multicast reception and the first timer is not running, the terminal device 110 may determine that the terminal device 110 performs multicast reception in an inactive or idle state.

[0158] If the terminal device 110 performs multicast reception in an inactive or idle state, the method 800 proceeds to block 820. In block 820, the terminal device 110 transmits a first message to the network device 120 including a preference for multicast reception in an inactive or idle state.

[0159] In block 830, the terminal device 110 receives a second message from the network device 120 indicating multicast reception in an inactive or idle state and including multicast settings for the multicast reception.

[0160] In some embodiments, the multicast configuration may include at least one of an indication indicating the multicast reception in the inactive or idle state, a list of multicast configurations for cell reselection, a multicast frequency priority for cell reselection, a multicast allowed cell list indicating a first set of cells for which the multicast configuration is allowed for the multicast reception, or a neighbor cell list indicating a second set of cells providing a multicast service that the terminal device is receiving. In some embodiments, the list of multicast configurations may include at least one of a C-RNTI for a cell, or a G-RNTI for a cell.

[0161] In block 840, the terminal device 110 performs the multicast reception in the inactive or idle state based on the multicast setting.

[0162] In some embodiments, terminal device 110 may start a second timer upon transmission of the first message and disable the started first timer upon reception of the multicast data. If the second timer expires and the second message is not received, terminal device 110 may enable the first timer. In some embodiments, terminal device 110 may stop the second timer upon reception of the second message.

[0163] In some embodiments, if the multicast configuration includes an indication of multicast reception in an inactive or idle state, the terminal device 110 may continue to receive multicast data in an inactive or idle state. In some embodiments, the multicast configuration includes a list of multicast configurations for cell reselection, and when the terminal device reselects to a first cell, the terminal device 110 may apply the multicast configuration for the first cell from the list of multicast configurations. In some embodiments, if the multicast configuration includes a multicast frequency priority for cell reselection, the terminal device 110 may perform the cell reselection based on the multicast frequency priority. In some embodiments, if the multicast configuration includes a multicast allowed cell list, the terminal device 110 may apply the multicast configuration to a second cell in the multicast allowed cell list, when the terminal device 110 reselects to the second cell. In some embodiments, if the multicast configuration includes a neighbor cell list, the terminal device 110 may apply and store the neighbor cell list for multicast reception.

[0164] In some embodiments, terminal device 110 may receive an inquiry from network device 120 about the capabilities of terminal device 110 and transmit to network device 120 the capabilities of terminal device 110 for multicast reception in an inactive or idle state.

[0165] In some embodiments, the terminal device 110 may receive a paging message indicating multicast reception in a connected state from the network device 120. If the terminal device 110 is receiving a multicast session in an inactive or idle state and the multicast session is a multicast session in which the terminal device 110 is interested in the paging message, the terminal device 110 may skip the paging message. In some embodiments, if the terminal device 110 is not receiving a multicast session in an inactive or idle state and the multicast session is a multicast session in which the terminal device is interested in the paging message, the terminal device 110 may perform multicast reception in a connected state.

[0166] In some embodiments, terminal device 110 may receive a paging message from the network device indicating multicast reception in a connected state and including another multicast setting for multicast reception in a connected state, and perform multicast reception in the connected state based on the another multicast setting. In some embodiments, the another multicast setting includes at least one of an indication indicating the multicast reception in the connected state and a multicast setting for the connected state. In some embodiments, if the another multicast setting includes an indication indicating multicast reception in a connected state, terminal device 110 may enter a connected state and perform multicast reception in the connected state based on the multicast setting in an inactive or idle state.

[0167] In some embodiments, the terminal device 110 may determine whether a signal quality of a channel between the terminal device and the network device is below a threshold quality. In some embodiments, the terminal device 110 may determine whether a signal reception level is below a threshold level. If the signal reception level is below the threshold level, the terminal device 110 may determine that the signal quality is below the threshold quality. In some embodiments, the terminal device 110 may determine whether a non-cell edge criterion is met. If the non-cell edge criterion is not met, the terminal device 110 may determine that the signal quality is below the threshold quality. In some embodiments, if the signal quality is below the threshold quality, the terminal device 110 may initiate random access to enter a connection state with the network device 120.

[0168] In some embodiments, when cell reselection to the third cell occurs, the terminal device 110 may initiate random access to the third cell for multicast reception. In some embodiments, when the terminal device 110 is receiving a multicast service but is not configured to have a multicast configuration, the terminal device 110 may initiate random access for multicast reception. In some embodiments, when the terminal device 110 is receiving a multicast service and the neighbor cell information stored for multicast includes the third cell, and the terminal device 110 does not have a multicast configuration for the third cell, the terminal device 110 may initiate random access for multicast reception.

[0169] In some embodiments, when the terminal device 110 is receiving a multicast service and the terminal device does not have a multicast configuration for the third cell, the terminal device 110 may determine whether one of the multicast sessions the terminal device is receiving matches a multicast session indicated in a list of multicast sessions broadcast by the third cell, and if one of the multicast sessions the terminal device is receiving matches a multicast session indicated in the list, the terminal device 110 may initiate random access for multicast reception.

[0170] The method 800 allows the terminal device to accurately or rationally enter an inactive or idle state to receive a multicast service. Additionally, the terminal device may receive a multicast configuration to ensure service continuity upon cell reselection.

[0171] 9 illustrates another exemplary communication method 900 implemented in a terminal device, according to some embodiments of the present disclosure. For example, the method 900 may be performed in a terminal device 110 as shown in FIG. For purposes of explanation, the method 900 will be described below with reference to FIG. It should be understood that the method 900 may include additional blocks not shown and / or omit some blocks that are shown, and that the scope of the present disclosure is not limited in this respect.

[0172] In block 910, the terminal device 110 in a connected state receives a third message from the network device 120 including multicast settings for multicast reception of terminal devices in an inactive or idle state.

[0173] In some embodiments, the multicast configuration may include at least one of an indication indicating the multicast reception in the inactive or idle state, a list of multicast configurations for cell reselection, a multicast frequency priority for cell reselection, a multicast allowed cell list indicating a first set of cells for which the multicast configuration is allowed for the multicast reception, or a neighbor cell list indicating a second set of cells providing a multicast service that the terminal device is receiving. In some embodiments, the list of multicast configurations may include at least one of a C-RNTI for a cell, or a G-RNTI for a cell.

[0174] In block 920, terminal device 110 determines whether terminal device 110 performs multicast reception in an inactive or idle state.

[0175] In some embodiments, when multicast data is received and the first timer is not running, the terminal device 110 may start the first timer. When unicast data is received or transmitted, the terminal device 110 may restart the first timer. In some embodiments, when the first timer expires, the terminal device 110 may determine that the terminal device 110 performs multicast reception in an inactive or idle state. Alternatively, when the terminal device 110 enters an inactive or idle state to perform multicast reception and the first timer is not running, the terminal device 110 may determine that the terminal device 110 performs multicast reception in an inactive or idle state.

[0176] If the terminal device 110 performs multicast reception in an inactive or idle state, the method 900 proceeds to block 930. In block 930, the terminal device 110 performs the multicast reception in the inactive or idle state based on the multicast setting.

[0177] In some embodiments, if the multicast configuration includes an indication of multicast reception in an inactive or idle state, the terminal device 110 may continue to receive multicast data in an inactive or idle state. In some embodiments, the multicast configuration includes a list of multicast configurations for cell reselection, and when the terminal device reselects to a first cell, the terminal device 110 may apply the multicast configuration for the first cell from the list of multicast configurations. In some embodiments, if the multicast configuration includes a multicast frequency priority for cell reselection, the terminal device 110 may perform the cell reselection based on the multicast frequency priority. In some embodiments, if the multicast configuration includes a multicast allowed cell list, the terminal device 110 may apply the multicast configuration to a second cell in the multicast allowed cell list, when the terminal device 110 reselects to the second cell. In some embodiments, if the multicast configuration includes a neighbor cell list, the terminal device 110 may apply and store the neighbor cell list for multicast reception.

[0178] In some embodiments, terminal device 110 may receive an inquiry from network device 120 about the capabilities of terminal device 110 and transmit to network device 120 the capabilities of terminal device 110 for multicast reception in an inactive or idle state.

[0179] In some embodiments, the terminal device 110 may receive a paging message indicating multicast reception in a connected state from the network device 120. If the terminal device 110 is receiving a multicast session in an inactive or idle state and the multicast session is a multicast session in which the terminal device 110 is interested in the paging message, the terminal device 110 may skip the paging message. In some embodiments, if the terminal device 110 is not receiving a multicast session in an inactive or idle state and the multicast session is a multicast session in which the terminal device is interested in the paging message, the terminal device 110 may perform multicast reception in a connected state.

[0180] In some embodiments, terminal device 110 may receive from the network device a paging message indicating multicast reception in a connected state and including another multicast setting for multicast reception in a connected state, and perform multicast reception in the connected state based on the another multicast setting. In some embodiments, the another multicast setting includes at least one of an indication indicating the multicast reception in the connected state and a multicast setting for the connected state. In some embodiments, if the another multicast setting includes an indication indicating multicast reception in a connected state, terminal device 110 may enter a connected state and perform multicast reception in the connected state based on the multicast setting in an inactive or idle state.

[0181] In some embodiments, the terminal device 110 may determine whether a signal quality of a channel between the terminal device and the network device is below a threshold quality. In some embodiments, the terminal device 110 may determine whether a signal reception level is below a threshold level. If the signal reception level is below the threshold level, the terminal device 110 may determine that the signal quality is below the threshold quality. In some embodiments, the terminal device 110 may determine whether a non-cell edge criterion is met. If the non-cell edge criterion is not met, the terminal device 110 may determine that the signal quality is below the threshold quality. In some embodiments, if the signal quality is below the threshold quality, the terminal device 110 may initiate random access to enter a connection state with the network device 120.

[0182] In some embodiments, when cell reselection to the third cell occurs, the terminal device 110 may initiate random access to the third cell for multicast reception. In some embodiments, when the terminal device 110 is receiving a multicast service but is not configured to have a multicast configuration, the terminal device 110 may initiate random access for multicast reception. In some embodiments, when the terminal device 110 is receiving a multicast service and the neighbor cell information stored for multicast includes the third cell, and the terminal device 110 does not have a multicast configuration for the third cell, the terminal device 110 may initiate random access for multicast reception.

[0183] In some embodiments, when the terminal device 110 is receiving a multicast service and the terminal device does not have a multicast configuration for the third cell, the terminal device 110 may determine whether one of the multicast sessions the terminal device is receiving matches a multicast session indicated in a list of multicast sessions broadcast by the third cell, and if one of the multicast sessions the terminal device is receiving matches a multicast session indicated in the list, the terminal device 110 may initiate random access for multicast reception.

[0184] Method 900 allows terminal devices to more flexibly enter an inactive or idle state to receive multicast services based on network implementation.

[0185] 10 illustrates yet another exemplary communication method 1000 implemented in a terminal device, according to some embodiments of the present disclosure. For example, the method 1000 may be performed in a terminal device 120 as shown in FIG. 1. For purposes of explanation, the method 1000 will be described below with reference to FIG. 1. It should be understood that the method 1000 may include additional blocks not shown and / or omit some blocks that are shown, and that the scope of the present disclosure is not limited in this respect.

[0186] In block 1010, the terminal device 110 receives a fourth message from the network device 120 indicating multicast reception in an inactive or idle state and including multicast settings for the multicast reception including at least one of an indication of the multicast reception in the inactive or idle state, a list of multicast settings specific to the terminal device 110 for cell reselection, or a multicast frequency priority for cell reselection. In some embodiments, the list of multicast settings may include at least one of a cell radio network temporary identifier for the cell, or a group radio network temporary identifier for the cell.

[0187] In block 1020, the terminal device 110 performs the multicast reception in the inactive or idle state based on the multicast setting.

[0188] In some embodiments, if the multicast configuration includes an indication of multicast reception in an inactive or idle state, the terminal device 110 may continue to receive multicast data in an inactive or idle state. In some embodiments, the multicast configuration includes a list of multicast configurations for cell reselection, and when the terminal device reselects to a first cell, the terminal device 110 may apply the multicast configuration for the first cell from the list of multicast configurations. In some embodiments, if the multicast configuration includes a multicast frequency priority for cell reselection, the terminal device 110 may perform the cell reselection based on the multicast frequency priority. In some embodiments, if the multicast configuration includes a multicast allowed cell list, the terminal device 110 may apply the multicast configuration to a second cell in the multicast allowed cell list, when the terminal device 110 reselects to the second cell. In some embodiments, if the multicast configuration includes a neighbor cell list, the terminal device 110 may apply and store the neighbor cell list for multicast reception.

[0189] In some embodiments, terminal device 110 may receive an inquiry from network device 120 about the capabilities of terminal device 110 and transmit to network device 120 the capabilities of terminal device 110 for multicast reception in an inactive or idle state.

[0190] In some embodiments, the terminal device 110 may receive a paging message indicating multicast reception in a connected state from the network device 120. If the terminal device 110 is receiving a multicast session in an inactive or idle state and the multicast session is a multicast session in which the terminal device 110 is interested in the paging message, the terminal device 110 may skip the paging message. In some embodiments, if the terminal device 110 is not receiving a multicast session in an inactive or idle state and the multicast session is a multicast session in which the terminal device is interested in the paging message, the terminal device 110 may perform multicast reception in a connected state.

[0191] In some embodiments, terminal device 110 may receive from the network device a paging message indicating multicast reception in a connected state and including another multicast setting for multicast reception in a connected state, and perform multicast reception in the connected state based on the another multicast setting. In some embodiments, the another multicast setting includes at least one of an indication indicating the multicast reception in the connected state and a multicast setting for the connected state. In some embodiments, if the another multicast setting includes an indication indicating multicast reception in a connected state, terminal device 110 may enter a connected state and perform multicast reception in the connected state based on the multicast setting in an inactive or idle state.

[0192] In some embodiments, the terminal device 110 may determine whether a signal quality of a channel between the terminal device and the network device is below a threshold quality. In some embodiments, the terminal device 110 may determine whether a signal reception level is below a threshold level. If the signal reception level is below the threshold level, the terminal device 110 may determine that the signal quality is below the threshold quality. In some embodiments, the terminal device 110 may determine whether a non-cell edge criterion is met. If the non-cell edge criterion is not met, the terminal device 110 may determine that the signal quality is below the threshold quality. In some embodiments, if the signal quality is below the threshold quality, the terminal device 110 may initiate random access to enter a connection state with the network device 120.

[0193] In some embodiments, when cell reselection to the third cell occurs, the terminal device 110 may initiate random access to the third cell for multicast reception. In some embodiments, when the terminal device 110 is receiving a multicast service but is not configured to have a multicast configuration, the terminal device 110 may initiate random access for multicast reception. In some embodiments, when the terminal device 110 is receiving a multicast service and the neighbor cell information stored for multicast includes the third cell, and the terminal device 110 does not have a multicast configuration for the third cell, the terminal device 110 may initiate random access for multicast reception.

[0194] In some embodiments, when the terminal device 110 is receiving a multicast service and the terminal device does not have a multicast configuration for the third cell, the terminal device 110 may determine whether one of the multicast sessions the terminal device is receiving matches a multicast session indicated in a list of multicast sessions broadcast by the third cell, and if one of the multicast sessions the terminal device is receiving matches a multicast session indicated in the list, the terminal device 110 may initiate random access for multicast reception.

[0195] The method 1000 allows a terminal device to more flexibly and quickly enter an inactive or idle state to receive a multicast service based on a predefined multicast setting.

[0196] 11 illustrates an example communication method 1100 implemented in a network device according to some embodiments of the present disclosure. For example, method 1000 may be performed in network device 120 as shown in FIG. 1. For purposes of explanation, method 1000 will be described below with reference to FIG. 1. It should be understood that method 1000 may include additional blocks not shown and / or omit some of the blocks shown, and that the scope of the present disclosure is not limited in this respect.

[0197] At block 1110, the network device 120 receives a first message from the end device 110 including preferences for multicast reception in an inactive or idle state.

[0198] In block 1120, the network device 120 sends a second message to the terminal device 110 indicating the multicast reception in the inactive or idle state and including a multicast setting for the multicast reception.

[0199] In some embodiments, the multicast configuration may include at least one of an indication indicating the multicast reception in the inactive or idle state, a list of multicast configurations for cell reselection, a multicast frequency priority for cell reselection, a multicast allowed cell list indicating a first set of cells for which the multicast configuration is allowed for the multicast reception, or a neighbor cell list indicating a second set of cells providing a multicast service that the terminal device is receiving. In some embodiments, the list of multicast configurations may include at least one of a C-RNTI for a cell, or a G-RNTI for a cell.

[0200] In some embodiments, the network device 120 may send an inquiry to the terminal device 110 regarding the capabilities of the terminal device 110 and receive from the terminal device 110 the capabilities of the terminal device 110 for multicast reception in an inactive or idle state.

[0201] In some embodiments, the network device 120 may further transmit a paging message indicating multicast reception in a connected state and including another multicast setting for multicast reception in a connected state to the terminal device 110. In some embodiments, the another multicast setting includes at least one of an indication indicating the multicast reception in the connected state and a multicast setting for the connected state.

[0202] In some embodiments, the network device 120 may further broadcast a list of multicast sessions supported by the network device.

[0203] Thus, the network device may indicate to the terminal device that multicast reception should be performed in an inactive or idle state based on the terminal device's request.

[0204] 12 illustrates another example communication method 1200 implemented in a network device, according to some embodiments of the present disclosure. For example, method 1200 may be performed in network device 120 as shown in FIG. 1. For purposes of explanation, method 1200 will be described below with reference to FIG. 1. It should be understood that method 1200 may include additional blocks not shown and / or omit some blocks that are shown, and that the scope of the present disclosure is not limited in this respect.

[0205] In block 1210, the network device 120 generates multicast settings for multicast reception of an end device in an inactive or idle state.

[0206] In block 1220, the network device 120 sends a third message including the multicast configuration to the terminal devices 110 in a connected state.

[0207] In some embodiments, the multicast configuration may include at least one of an indication indicating the multicast reception in the inactive or idle state, a list of multicast configurations for cell reselection, a multicast frequency priority for cell reselection, a multicast allowed cell list indicating a first set of cells for which the multicast configuration is allowed for the multicast reception, or a neighbor cell list indicating a second set of cells providing a multicast service that the terminal device is receiving. In some embodiments, the list of multicast configurations may include at least one of a C-RNTI for a cell, or a G-RNTI for a cell.

[0208] In some embodiments, the network device 120 may send an inquiry to the terminal device 110 regarding the capabilities of the terminal device 110 and receive from the terminal device 110 the capabilities of the terminal device 110 for multicast reception in an inactive or idle state.

[0209] In some embodiments, the network device 120 may further transmit a paging message indicating multicast reception in a connected state and including another multicast setting for the multicast reception in the connected state to the terminal device 110. In some embodiments, the another multicast setting includes at least one of an indication indicating the multicast reception in the connected state and a multicast setting for the connected state.

[0210] In some embodiments, the network device 120 may further broadcast a list of multicast sessions supported by the network device.

[0211] Thus, the network device may pre-configure the terminal device with multicast settings for multicast reception in an inactive or idle state.

[0212] 13 illustrates yet another exemplary communication method 1300 implemented in a network device, in accordance with some embodiments of the present disclosure. For example, method 1300 may be performed in network device 120 as shown in FIG. 1. For purposes of explanation, method 1300 will be described below with reference to FIG. 1. It should be understood that method 1300 may include additional blocks not shown and / or omit some blocks that are shown, and that the scope of the present disclosure is not limited in this respect.

[0213] In block 1310, the network device 120 generates multicast settings for multicast reception of a terminal device in an inactive or idle state, the multicast settings including at least one of an indication of the multicast reception in the inactive or idle state, a list of the terminal device specific multicast settings for cell reselection, or a multicast frequency priority for cell reselection.

[0214] In block 1320, network device 120 sends a fourth message indicating the multicast reception of terminal device 110 in the inactive or idle state and including multicast settings to terminal device 110. In some embodiments, the list of multicast settings may include at least one of a C-RNTI for a cell or a G-RNTI for a cell.

[0215] In some embodiments, the network device 120 may send an inquiry to the terminal device 110 regarding the capabilities of the terminal device 110 and receive from the terminal device 110 the capabilities of the terminal device 110 for multicast reception in an inactive or idle state.

[0216] In some embodiments, the network device 120 may further transmit a paging message indicating multicast reception in a connected state and including another multicast setting for multicast reception in a connected state to the terminal device 110. In some embodiments, the another multicast setting includes at least one of an indication indicating the multicast reception in the connected state and a multicast setting for the connected state.

[0217] In some embodiments, the network device 120 may further broadcast a list of multicast sessions supported by the network device.

[0218] Thus, the network device may set multicast settings for multicast reception in an inactive or idle state, as well as indicate said multicast reception. Examples of equipment and devices

[0219] Fig. 14 is a schematic block diagram of an apparatus 1400 suitable for implementing embodiments of the present disclosure. The apparatus 1400 may be considered as another exemplary implementation of the terminal device 110 or the network device 120 shown in Fig. 1. Thus, the apparatus 1400 may be implemented in the terminal device 110 or the network device 120, or as at least a part thereof.

[0220] As shown, the apparatus 1400 comprises a processor 1410, a memory 1420 coupled to the processor 1410, a suitable transmitter (TX) and receiver (RX) 1440 coupled to the processor 1410, and a communication interface coupled to the TX / RX 1440. The memory 1410 stores at least a portion of a program 1430. The TX / RX 1440 is used for bidirectional communication. The TX / RX 1440 has at least one antenna to facilitate communication, although the access nodes referred to herein may in practice have multiple antennas. The communication interface may represent any interface required for communication with other network elements, such as the X2 interface for bidirectional communication between eNB / gNB, the S1 / NG interface for communication between a Mobility Management Entity (MME) / Access and Mobility Management Function (AMF) / SGW / UPF and a gNB / eNB, the Un interface for communication between a gNB / eNB and a relay node (RN), and the Uu interface for communication between a gNB / eNB and a terminal device.

[0221] The program 1430 is assumed to include program instructions that, when executed by the associated processor 1410, enable the device 1400 to operate according to embodiments of the present disclosure, as described herein with reference to Figures 1-13. The embodiments of the present disclosure may be implemented by computer software executable by the processor 1410 of the device 1400, or by hardware, or by a combination of software and hardware. The processor 1410 may be configured to implement various embodiments of the present disclosure. Furthermore, the combination of the processor 1410 and the memory 1420 may form a processing means 1450 suitable for implementing various embodiments of the present disclosure.

[0222] The memory 1420 may be of any type suitable for a local technology network and may be implemented using any suitable data storage technology, such as, by way of non-limiting example, non-transitory computer-readable storage media, semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory. Although only one memory 1420 is shown in the device 1400, there may be several physically different memory modules in the device 1400. The processor 1410 may be of any type suitable for a local technology network and may include, by way of non-limiting example, one or more of a general purpose computer, a special purpose computer, a microprocessor, a digital signal processor (DSP) and a processor based on a multi-core processor architecture. The device 1400 may have multiple processors, for example application specific integrated circuit chips time-slaved to a clock that synchronizes the main processor.

[0223] In some embodiments, a terminal device comprises a circuit configured to, in accordance with a determination that the terminal device performs multicast reception in an inactive or idle state, send a first message to a network device including a preference for the multicast reception in the inactive or idle state, receive from the network device a second message indicating the multicast reception in the inactive or idle state and including a multicast setting for the multicast reception, and perform the multicast reception in the inactive or idle state based on the multicast setting.

[0224] In some embodiments, the terminal device comprises circuitry configured to receive, in a connected state, from a network device, a third message including a multicast setting for multicast reception of the terminal device in an inactive or idle state, and to perform the multicast reception in the inactive or idle state based on the multicast setting in accordance with a determination that the terminal device will perform the multicast reception in the inactive or idle state.

[0225] In some embodiments, the terminal device comprises circuitry configured to receive from a network device a fourth message indicating multicast reception in an inactive or idle state and including a multicast setting for the multicast reception, the multicast setting including at least one of an instruction for the multicast reception in the inactive or idle state, a list of multicast settings specific to the terminal device for cell reselection, or a multicast frequency priority for cell reselection, and to perform the multicast reception in the inactive or idle state based on the multicast setting.

[0226] In some embodiments, a network device comprises circuitry configured to receive a first message from a terminal device including a preference for multicast reception in an inactive or idle state, and to send to the terminal device a second message indicating the multicast reception in the inactive or idle state and including a multicast setting for the multicast reception.

[0227] In some embodiments, the network device comprises circuitry configured to generate multicast settings for multicast reception of a terminal device in an inactive or idle state and to send a third message including the multicast settings to the terminal device in a connected state.

[0228] In some embodiments, the network device comprises circuitry configured to generate multicast settings for multicast reception of a terminal device in an inactive or idle state, the multicast settings including at least one of an indication of the multicast reception in the inactive or idle state, a list of multicast settings specific to the terminal device for cell reselection, or a multicast frequency priority for cell reselection, and to send a fourth message to the terminal device indicating the multicast reception of the terminal device in the inactive or idle state and including the multicast settings.

[0229] The term "circuitry" as used herein may refer to hardware circuits and / or a combination of hardware circuits and software. For example, a circuit may be a combination of analog and / or digital hardware circuits and software / firmware. As a further example, a circuit may be any portion of a hardware processor with software, such as a digital signal processor, software, and memory that work together to perform various functions on a device, such as a terminal device or a network device. In yet another example, a circuit may be a hardware circuit and / or processor, such as a microprocessor or a portion of a microprocessor, that requires software / firmware for operation, but the software may not be present when not required for operation. As used herein, the term circuitry also encompasses merely a hardware circuit or processor, or a portion of a hardware circuit or processor, and its (or their) accompanying software and / or firmware implementations.

[0230] In summary, the embodiments of the present disclosure can provide the following solutions: Section 1 1. A method of communication comprising: According to a decision that the terminal device performs multicast reception in an inactive or idle state, sending, in the terminal device, to a network device, a first message including a preference for the multicast reception in the inactive or idle state; receiving a second message from the network device indicating the multicast reception in the inactive or idle state and including a multicast setting for the multicast reception; performing the multicast reception in the inactive or idle state based on the multicast configuration. Section 2 1. A method of communication comprising: receiving, in a terminal device in a connected state, from a network device, a third message including a multicast setting for multicast reception of the terminal device in an inactive or idle state; and performing the multicast reception in the inactive or idle state based on the multicast setting in accordance with a decision by the terminal device to perform the multicast reception in the inactive or idle state. Section 3 starting a first timer pursuant to determining that multicast data is received and the first timer is not running; restarting the first timer in response to a determination that unicast data has been received or transmitted; The method according to claim 1 or 2, further comprising: determining, according to a determination that the first timer has expired, that the terminal device performs multicast reception in an inactive or idle state. Section 4 starting a first timer pursuant to determining that multicast data is received and the first timer is not running; restarting the first timer in response to a determination that unicast data has been received or transmitted; determining that the terminal device enters the inactive or idle state to perform the multicast reception and that the first timer is not running, the terminal device performs the multicast reception in the inactive or idle state; 3. The method of claim 1 or 2, further comprising: Section 5 The multicast setting is an indication of said multicast reception in said inactive or idle state; A list of multicast settings for cell reselection; Multicast frequency priority for cell reselection; a multicast allowed cell list indicating a first set of cells in which the multicast configuration is allowed for the multicast reception; or a neighboring cell list indicating a second set of cells providing the multicast service being received by the terminal device; 3. The method according to claim 1 or 2. Section 6 The list of multicast settings may include: a cell radio network temporary identifier for the cell, or A group radio network temporary identifier for the cell; 6. The method of claim 5, comprising at least one of: Section 7 starting a second timer upon said transmitting of said first message; Disabling a first timer that is started upon receiving the multicast data; enabling the first timer pursuant to a determination that the second timer has expired and the second message has not been received; 2. The method of claim 1, further comprising: Section 8 stopping the second timer upon receipt of the second message; 8. The method of claim 7, further comprising: Section 9 1. A method of communication comprising: receiving, in the terminal device, from a network device, a fourth message indicating multicast reception in an inactive or idle state, the fourth message including a multicast setting for the multicast reception, the multicast setting including at least one of an instruction for the multicast reception in the inactive or idle state, a list of multicast settings specific to the terminal device for cell reselection, or a multicast frequency priority for cell reselection; performing the multicast reception in the inactive or idle state based on the multicast configuration. Section 10 The list of multicast settings may include: a cell radio network temporary identifier for the cell, or A group radio network temporary identifier for the cell; 10. The method of claim 9, comprising at least one of: Section 11 The performing of multicast reception includes: continuing to receive multicast data in the inactive or idle state in accordance with a determination that the multicast configuration includes an indication of multicast reception in the inactive or idle state; the multicast configuration includes a list of multicast configurations for cell reselection, and applying a multicast configuration for the first cell from the list of multicast configurations according to a decision that the terminal device reselects to a first cell; performing the cell reselection based on the multicast frequency priority in accordance with a determination that the multicast configuration includes a multicast frequency priority for cell reselection; applying the multicast configuration to a second cell in the multicast allowed cell list when the terminal device reselects to the second cell in the multicast allowed cell list according to the determination that the multicast configuration includes a multicast allowed cell list; or According to a determination that the multicast configuration includes a neighbor cell list, applying and storing the neighbor cell list for the multicast reception; 10. The method of claim 1, 2 or 9, comprising: Section 12 receiving an inquiry from the network device regarding capabilities of the terminal device; transmitting to the network device a capability of the terminal device for multicast reception in the inactive or idle state; 10. The method of claim 1, 2 or 9, further comprising: Section 13 receiving a paging message from the network device indicating multicast reception in a connected state; skipping the paging message in accordance with a determination in the paging message that the terminal device is receiving a multicast session in the inactive or idle state and that the multicast session is a multicast session in which the terminal device is interested; 10. The method of claim 1, 2 or 9, further comprising: Section 14 performing the multicast reception in the connected state according to a determination that the terminal device is not receiving the multicast session in the inactive or idle state and that the multicast session is a multicast session in which the terminal device is interested in the paging message; 14. The method of claim 13, further comprising: Section 15 receiving a paging message from the network device, the paging message indicating multicast reception in a connected state and including another multicast setting for the multicast reception in the connected state; performing the multicast reception in the connected state based on the different multicast setting; 10. The method of claim 1, 2 or 9, further comprising: Section 16 The other multicast setting is an indication indicating the multicast reception in the connected state; A multicast setting for the connection state; 20. The method of claim 15, comprising at least one of the following: Section 17 The performing of the multicast reception in the connected state includes: In response to a determination that the other multicast configuration includes an indication of receiving the multicast in the connection state, Entering the connected state, performing the multicast reception in the connected state based on the multicast setting in the inactive or idle state; 16. The method of claim 15, comprising: Section 18 determining whether a signal quality of a channel between the terminal device and the network device is below a threshold quality; initiating random access to enter into a connection state with the network device in response to determining that the signal quality is below the threshold quality; 10. The method of claim 1, 2 or 9, further comprising: Section 19 Determining whether the signal quality is below the threshold quality includes: determining whether a signal reception level is below a threshold level; determining that the signal quality is below the threshold quality in response to determining that the signal reception level is below the threshold level; 20. The method of claim 18, comprising: Section 20 Determining whether the signal quality is below the threshold quality includes: determining whether a non-cell edge criterion is met; and determining that the signal quality is below the threshold quality in accordance with a determination that the non-cell edge criterion is not met; 20. The method of claim 18, comprising: Section 21 initiating random access to the third cell for the multicast reception in accordance with a determination that cell reselection to the third cell has occurred; 10. The method of claim 1, 2 or 9, further comprising: Section 22 Initiating the random access includes: initiating the random access for the multicast reception according to a determination that the terminal device is receiving a multicast service but is not configured to have the multicast configuration; 22. The method of claim 21, comprising: Section 23 Initiating the random access includes: Initiating the random access for the multicast reception according to a determination that the terminal device is receiving a multicast service, that neighbor cell information stored for multicast includes the third cell, and that the terminal device does not have a multicast setting for the third cell; 22. The method of claim 21, comprising: Section 24 Initiating the random access includes: The terminal device is receiving a multicast service, and according to a determination that the terminal device does not have a multicast configuration for the third cell, determining whether one of the multicast sessions being received by the terminal device matches a multicast session indicated in a list of multicast sessions being broadcast by the third cell; initiating the random access for the multicast reception according to a determination that the one of the multicast sessions being received by the terminal device matches the multicast session indicated in the list; 22. The method of claim 21, comprising: Section 25 1. A method of communication comprising: receiving, at the network device, a first message from the terminal device, the first message including a preference for multicast reception in an inactive or idle state; and sending to the terminal device a second message indicating the multicast reception in the inactive or idle state and including a multicast setting for the multicast reception. Section 26 1. A method of communication comprising: generating, in a network device, a multicast setting for multicast reception of a terminal device in an inactive or idle state; and sending a third message to the terminal device in a connected state, the third message including the multicast configuration. Section 27 The multicast setting is an indication of said multicast reception in said inactive or idle state; A list of multicast settings for cell reselection; Multicast frequency priority for cell reselection; a multicast allowed cell list indicating a first set of cells in which the multicast configuration is allowed for the multicast reception; or a neighboring cell list indicating a second set of cells providing the multicast service being received by the terminal device; 27. The method according to claim 25 or 26. Section 28 The list of multicast settings may include: a cell radio network temporary identifier for the cell, or A group radio network temporary identifier for the cell; 28. The method of claim 27, comprising at least one of the following: Section 29 1. A method of communication comprising: generating, in a network device, a multicast setting for multicast reception of a terminal device in an inactive or idle state, the multicast setting including at least one of an indication of the multicast reception in the inactive or idle state, a list of multicast settings specific to the terminal device for cell reselection, or a multicast frequency priority for cell reselection; and sending to the terminal device a fourth message indicating the multicast reception of the terminal device in the inactive or idle state and including the multicast configuration. Section 30 The list of multicast settings may include: a cell radio network temporary identifier for the cell, or A group radio network temporary identifier for the cell; 30. The method of claim 29, comprising at least one of the following: Section 31 sending to said terminal device an inquiry about the capabilities of said terminal device; receiving from the terminal device a capability for the multicast reception in the inactive or idle state of the terminal device; 30. The method of claim 25, 26 or 29, further comprising: Section 32 sending a paging message to the terminal device indicating multicast reception in a connected state and including another multicast setting for the multicast reception in the connected state; 30. The method of claim 25, 26 or 29, further comprising: Section 33 The other multicast setting is an indication indicating the multicast reception in the connected state; A multicast setting for the connection state; 33. The method of claim 32, comprising at least one of the following: Section 34 broadcasting a list of multicast sessions supported by said network device; 30. The method of claim 25, 26 or 29, further comprising: Section 35 A processor configured to cause a terminal device to execute the method according to any one of claims 1 to 24. Terminal device. Section 36 A processor configured to cause a network device to perform the method according to any one of claims 25 to 34. Network device.

[0231] Overall, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic, or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software that may be executed by a controller, microprocessor, or other computing device. Although various aspects of the embodiments of the present disclosure have been illustrated and described using block diagrams, flow charts, or some other pictorial representations, it should be understood that the blocks, devices, systems, techniques, or methods described herein may be implemented, by way of non-limiting examples, in hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing device, or any combination thereof.

[0232] The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions, such as instructions included in program modules, that execute in a device on a target real or virtual processor to perform the process or method described above with reference to Figures 1-13. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform particular tasks or implement particular abstract data types. In various embodiments, the functionality of the program modules may be combined or split between program modules as appropriate. The machine-executable instructions of the program modules may be executed in local or distributed devices. In a distributed device, the program modules may be located in both local and remote storage media.

[0233] The program codes for carrying out the methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, a special purpose computer, or other programmable data processing equipment, and when executed by the processor or controller, the program code causes the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may run entirely on the machine, partially on the machine, as a separate software package, partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0234] The above program code may be embodied on a machine-readable medium, which may be any tangible medium that contains or stores a program for use by or in conjunction with an instruction execution system, apparatus, or device. The machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. The machine-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of machine-readable storage media include electrical connections, including one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable-programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0235] It should be understood that although operations have been described in a particular order, it is not required that such operations be performed in the particular order or sequence shown, or that all of the operations shown be performed, in order to achieve desired results. In some situations, multitasking and parallel processing may be advantageous. Similarly, although the above discussion includes details of some specific embodiments, these should not be construed as limitations on the scope of the disclosure, but rather as descriptions of features that may be specific to certain embodiments. Some features that are described in the context of individual embodiments may be implemented in combination in an embodiment. Conversely, various features that are described in the context of an embodiment may be implemented in multiple embodiments separately or in any suitable subcombination.

[0236] Although the present disclosure has been described in language specific to structural features and / or methodological acts, it is to be understood that the present disclosure, as defined by the appended claims, is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

1. 1. A method of communication comprising: According to a decision that the terminal device performs multicast reception in an inactive or idle state, sending, in the terminal device, to a network device, a first message including a preference for the multicast reception in the inactive or idle state; receiving a second message from the network device indicating the multicast reception in the inactive or idle state and including a multicast setting for the multicast reception; performing the multicast reception in the inactive or idle state based on the multicast configuration; The method includes:

2. 1. A method of communication comprising: receiving, in a terminal device in a connected state, from a network device, a third message including a multicast setting for multicast reception of the terminal device in an inactive or idle state; According to a decision that the terminal device performs the multicast reception in the inactive or idle state, the terminal device performs the multicast reception in the inactive or idle state based on the multicast setting; The method includes:

3. starting a first timer pursuant to determining that multicast data is received and the first timer is not running; restarting the first timer in response to a determination that unicast data has been received or transmitted; determining, according to a determination that the first timer has expired, that the terminal device performs multicast reception in an inactive or idle state; The method of claim 1 or 2, further comprising:

4. starting a first timer pursuant to determining that multicast data is received and the first timer is not running; restarting the first timer in response to a determination that unicast data has been received or transmitted; determining that the terminal device enters the inactive or idle state to perform the multicast reception and that the first timer is not running, the terminal device performs the multicast reception in the inactive or idle state; The method of claim 1 or 2, further comprising:

5. The multicast setting is an indication of said multicast reception in said inactive or idle state; A list of multicast settings for cell reselection; Multicast frequency priority for cell reselection; a multicast allowed cell list indicating a first set of cells in which the multicast configuration is allowed for the multicast reception; or a neighboring cell list indicating a second set of cells providing a multicast service to which the terminal device is receiving; The method according to claim 1 or 2.

6. The list of multicast settings may include: a cell radio network temporary identifier for the cell, or A group radio network temporary identifier for the cell; The method of claim 5 , comprising at least one of:

7. starting a second timer upon said transmitting of said first message; Disabling a first timer that is started upon receiving the multicast data; enabling the first timer pursuant to a determination that the second timer has expired and the second message has not been received; and The method of claim 1 further comprising:

8. stopping the second timer upon receipt of the second message; The method of claim 7 further comprising:

9. 1. A method of communication comprising: receiving, in the terminal device, from a network device, a fourth message indicating multicast reception in an inactive or idle state, the fourth message including a multicast setting for the multicast reception, the multicast setting including at least one of an instruction for the multicast reception in the inactive or idle state, a list of multicast settings specific to the terminal device for cell reselection, or a multicast frequency priority for cell reselection; performing the multicast reception in the inactive or idle state based on the multicast configuration; The method includes:

10. The list of multicast settings may include: a cell radio network temporary identifier for the cell, or A group radio network temporary identifier for the cell; The method of claim 9 , comprising at least one of:

11. The performing of multicast reception includes: continuing to receive multicast data in the inactive or idle state in accordance with a determination that the multicast configuration includes an indication of multicast reception in the inactive or idle state; the multicast configuration includes a list of multicast configurations for cell reselection, and applying, in accordance with a decision that the terminal device reselects to a first cell, a multicast configuration for the first cell from the list of multicast configurations; performing the cell reselection based on the multicast frequency priority in accordance with a determination that the multicast configuration includes a multicast frequency priority for cell reselection; applying the multicast configuration to a second cell in the multicast allowed cell list when the terminal device reselects to the second cell in the multicast allowed cell list according to the determination that the multicast configuration includes a multicast allowed cell list; or According to a determination that the multicast configuration includes a neighbor cell list, applying and storing the neighbor cell list for the multicast reception; 10. The method of claim 1, 2 or 9, comprising:

12. receiving an inquiry from the network device regarding capabilities of the terminal device; transmitting to the network device a capability of the terminal device for multicast reception in the inactive or idle state; 10. The method of claim 1, 2 or 9, further comprising:

13. receiving a paging message from the network device indicating multicast reception in a connected state; skipping the paging message in accordance with a determination in the paging message that the terminal device is receiving a multicast session in the inactive or idle state and that the multicast session is a multicast session in which the terminal device is interested; 10. The method of claim 1, 2 or 9, further comprising:

14. performing the multicast reception in the connected state according to a determination that the terminal device is not receiving the multicast session in the inactive or idle state and that the multicast session is a multicast session in which the terminal device is interested in the paging message; The method of claim 13 further comprising:

15. receiving a paging message from the network device, the paging message indicating multicast reception in a connected state and including another multicast setting for the multicast reception in the connected state; performing the multicast reception in the connected state based on the different multicast setting; 10. The method of claim 1, 2 or 9, further comprising:

16. The other multicast setting is an indication indicating the multicast reception in the connected state; A multicast setting for the connection state; 16. The method of claim 15, comprising at least one of:

17. The performing of the multicast reception in the connected state includes: In response to a determination that the other multicast configuration includes an indication of receiving the multicast in the connection state, Entering the connection state, performing the multicast reception in the connected state based on the multicast setting in the inactive or idle state; 16. The method of claim 15, comprising:

18. determining whether a signal quality of a channel between the terminal device and the network device is below a threshold quality; initiating random access to enter into a connection state with the network device in response to determining that the signal quality is below the threshold quality; 10. The method of claim 1, 2 or 9, further comprising:

19. initiating random access to the target cell for said multicast reception in accordance with a determination that cell reselection to the target cell has occurred; 10. The method of claim 1, 2 or 9, further comprising:

20. A processor configured to cause a terminal device to carry out the method according to any one of claims 1 to 19. Terminal device.

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