Method, device and computer storage medium for communication

Abstract

Embodiments of the present disclosure relate to methods, devices, and computer-readable media for communication. The communication method implemented by a terminal device includes: determining whether to transmit the uplink data in an inactive state of the terminal device based on characteristics of a service associated with the uplink data; and restoring a radio bearer for transmission of the uplink data in an inactive state based on the determination that the uplink data is to be transmitted in an inactive state; and transmitting the uplink data to a network device based on the radio bearer while the terminal device is in an inactive state. The communication method implemented by the network device includes: receiving uplink data; and transmitting a response to the reception of the uplink data to the terminal device. In this way, a control scheme for small data transmission is provided.

Description

Technical Field

[0001] The disclosed embodiments generally relate to the field of telecommunications, and more particularly to a communication method, device, and computer storage medium for small data transfer (SDT) control. Background Art

[0002] Typically, a terminal device in an inactive state may still have small and infrequent data traffic to transmit (hereinafter also referred to as SDT). Prior to the 3rd Generation Partnership Project (3GPP) Release 16, the inactive state could not support data transmission, and the terminal device had to restore the connection for any downlink and uplink data. Connection establishment and subsequent release to the inactive state occurred for every data transmission, no matter how small and infrequent the data packets were. This would result in unnecessary power consumption and signaling overhead.

[0003] In this case, 3GPP Release 17 has approved SDT based on a random access channel (RACH) and a preconfigured physical uplink shared channel (PUSCH) resource in an inactive state. Therefore, how to control SDT has become a hot issue. Summary of the invention

[0004] Generally speaking, embodiments of the present disclosure provide communication methods, devices, and computer storage media for SDT control.

[0005] In a first aspect, a method for communication is provided. The method comprises: determining, at a terminal device, whether to transmit the uplink data in an inactive state of the terminal device based on characteristics of a service associated with the uplink data; and recovering a radio bearer for transmission of the uplink data in the inactive state based on the determination that the uplink data is to be transmitted in the inactive state; and transmitting the uplink data to the network device based on the radio bearer while the terminal device is in the inactive state.

[0006] In a second aspect, a method for communication is provided, comprising: receiving, at a network device, uplink data associated with a service, the uplink data being transmitted by a terminal device in an inactive state based on characteristics of the service; and transmitting a response to the reception of the uplink data to the terminal device.

[0007] In a third aspect, a terminal device is provided. The terminal device includes a processor and a memory coupled to the processor. The memory stores instructions, which, when executed by the processor, cause the terminal device to perform the method according to the first aspect of the present disclosure.

[0008] In a fourth aspect, a network device is provided. The network device includes a processor and a memory coupled to the processor. The memory stores instructions, which, when executed by the processor, cause the network device to perform the method according to the second aspect of the present disclosure.

[0009] In a fifth aspect, a computer readable medium having instructions stored thereon is provided. The instructions, when executed on at least one processor, cause the at least one processor to perform the method according to the first aspect of the present disclosure.

[0010] In a sixth aspect, a computer readable medium having instructions stored thereon is provided. The instructions, when executed on at least one processor, cause the at least one processor to perform the method according to the second aspect of the present disclosure.

[0011] Other features of the present disclosure will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The above and other objects, features and advantageous effects of the present disclosure will become more apparent through a more detailed description of some embodiments of the present disclosure in the accompanying drawings, in which:

[0013] Figure 1 shows an example communication network in which some embodiments of the present disclosure may be implemented;

[0014] Figure 2 A schematic diagram showing a communication process for SDT control according to some embodiments of the present disclosure is shown;

[0015] Figure 3 An example communication method implemented at a terminal device according to some embodiments of the present disclosure is shown;

[0016] Figure 4 An example method of transmitting uplink data in an inactive state according to some embodiments of the present disclosure is shown;

[0017] Figure 5 Another example method for transmitting uplink data based on a random access procedure according to some embodiments of the present disclosure is shown;

[0018] Figure 6 An example method for determining whether subsequent transmission is supported according to some embodiments of the present disclosure is shown;

[0019] Figure 7 An example communication method implemented at a network device according to some embodiments of the present disclosure is shown;

[0020] Figure 8 Another example communication method implemented at a network device according to some embodiments of the present disclosure is shown;

[0021] Fig. 9 Another example communication method implemented at a network device according to some embodiments of the present disclosure is shown; and

[0022] Fig.10 is a simplified block diagram of a device suitable for implementing embodiments of the present disclosure.

[0023] Throughout the drawings, the same or similar reference numerals refer to the same or similar elements. DETAILED DESCRIPTION

[0024] The principle of the present disclosure will now be described with reference to some embodiments. It should be understood that these embodiments are described only for illustrative purposes and to help those skilled in the art understand and implement the present disclosure without implying any limitation on the scope of the disclosure. The disclosure described herein can be implemented in various ways different from the modes described below.

[0025] In the following description and claims, unless defined otherwise, 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 belongs.

[0026] As used herein, the term "terminal device" refers to any device with wireless or wired communication capabilities. Examples of terminal devices include, but are not limited to: user equipment (UE), personal computer, desktop, mobile phone, cellular phone, smart phone, personal digital assistant (PDA), portable computer, tablet computer, wearable device, Internet of Things (IoT) device, Internet of Everything (IoE) device, machine type communication (MTC) device, vehicle-mounted device for V2X communication (where X represents pedestrian, vehicle or infrastructure / network), or image capture device such as digital camera, gaming device, music storage and playback device, or Internet tool that allows wireless or wired Internet access and browsing, etc. The term "terminal device" can be used interchangeably with UE, mobile station, subscriber station, mobile terminal, user terminal or wireless device. In addition, the term "network device" refers to a device that can provide or host a cell or coverage with which a terminal device can communicate. Examples of network devices include, but are not limited to, Node B (NodeB or NB), evolved Node B (eNodeB or eNB), next generation Node B (gNB), transmit receive point (TRP), remote radio unit (RRU), radio head (RH), remote radio head (RRH), low power nodes such as femto nodes, pico nodes, etc.

[0027] In one embodiment, the terminal device may be connected to a first network device and a second network device. One of the first network device and the second network device may be a primary 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 related to different RATs may be transmitted to the terminal device from at least one of the first network device and 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 related to 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 related to the reconfiguration of the terminal device configured by the second network device may be transmitted to the terminal device from the second network device directly or via the first network device.

[0028] As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The term "including" and its variations are to be interpreted as open-ended terms, which mean "including but not limited to". The term "based on" is to be interpreted as "based at least in part on". The terms "one embodiment" and "embodiment" are to be interpreted as "at least one embodiment". The term "another embodiment" is to be interpreted as "at least one other embodiment". The terms "first", "second", etc. may refer to different or the same objects. Other explicit and implicit definitions may be included below.

[0029] In some examples, values, processes, or devices are referred to as "best," "lowest," "highest," "minimum," "maximum," etc. It should be understood that such descriptions are intended to indicate that a selection may be made among a number of functional alternatives used, and that such a selection is not necessarily better, lesser, higher, or more preferred than other selections.

[0030] Figure 1 1 shows a schematic diagram of an example communication network 100 in which embodiments of the present disclosure may be implemented. Figure 1 As shown, the communication network 100 may include a network device 110 and a terminal device 120 served by the network device 110. The network device 110 and the terminal device 120 may communicate with each other via a channel such as a wireless communication channel. For example, the terminal device 120 may transmit a data packet (i.e., uplink data) to the network device 110, and the network device 110 may transmit a response to the reception of the uplink data to the terminal device 120.

[0031] It should be understood that Figure 1 The number and type of devices in are given for illustrative purposes and do not imply any limitation of the present disclosure. The communication network 100 may include any suitable number of network devices and / or terminal devices suitable for implementing the present disclosure. In addition, the communication network 100 may include any other devices other than network devices and terminal devices, such as core network elements, but they are omitted here to avoid obscuring the present invention.

[0032] The communication in the 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, Advanced LTE (LTE-A), Wideband Code Division Multiple Access (WCDMA), Code Division Multiple Access (CDMA), GSM EDGE Radio Access Network (GERAN), Machine Type Communication (MTC), etc. In addition, the communication may be performed according to any generation of communication protocols currently known or to be 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.

[0033] As described above, the terminal device 120 in an inactive state may still have small and infrequent data traffic to be transmitted (hereinafter also referred to as SDT). In some embodiments, small and infrequent data traffic may include smart phone applications, such as traffic from instant messaging (IM) services (whatsapp, QQ, wechat, etc.), heartbeat / keep-alive traffic from IM / email clients and other applications, and push notifications from various applications. In some embodiments, small and infrequent data traffic may include non-smart phone applications, such as traffic from wearables (periodic positioning information, etc.), sensors (industrial wireless sensor networks that transmit temperature, pressure readings, etc. periodically or in an event-triggered manner), and smart meters and smart meter networks that send periodic meter readings.

[0034] Currently, RACH-based schemes and transmissions on pre-configured PUSCH have been approved to perform SDT in an inactive state of a terminal device. However, no more detailed scheme on how to control the performance of SDT has been proposed. The embodiment of the present disclosure provides a communication scheme for SDT control. The scheme can implement the control of SDT in an inactive state of a terminal device. The principles and implementations of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0035] Figure 2 FIG. 2 is a schematic diagram showing a communication process 200 for SDT control according to some embodiments of the present disclosure. For the purpose of discussion, reference will be made to FIG. Figure 1Process 200 is described. Process 200 may include the following: Figure 1 The terminal device 120 and the network device 110 are shown.

[0036] In the case where the terminal device 120 in the inactive state has data packets to transmit (ie, uplink data), as Figure 2 As shown, the terminal device 120 can determine 201 whether to transmit uplink data in an inactive state. That is, the terminal device 120 can decide whether to perform SDT for transmission of uplink data. According to an embodiment of the present disclosure, the triggering of SDT is based on different businesses or services that trigger uplink data transmission.

[0037] In some embodiments, the terminal device 120 may initiate SDT when at least the following conditions are met: 1) the terminal device 120 is in a radio resource control (RRC) inactive state and the transmission is for a call initiated by a mobile terminal (i.e., uplink service); 2) the terminal device 120 supports SDT and the system information of the network device 110 also indicates support for SDT; 3) no fallback indication is received from the media access control (MAC) layer of the terminal device 120; and 4) the service triggering the transmission supports SDT.

[0038] In some embodiments for condition 4), the terminal device 120 may determine at least one of an access category and an access identifier of a service; and determine to transmit uplink data in an inactive state based on determining that at least one of the access category and the access identifier supports transmission of uplink data in an inactive state. In some embodiments, an access category or access identifier supporting SDT may be predefined. In some alternative embodiments, an access category or access identifier supporting SDT may be broadcast via system information from the network device 110. In some alternative embodiments, an access category or access identifier supporting SDT may be specifically configured to the terminal device 120 via an RRC message (e.g., an RRC release message or any other suitable message).

[0039] In some alternative embodiments, a specific access class or access identifier for SDT may be introduced. For example, the value of the specific access class or access identifier may be 10 or any other suitable number. In some alternative embodiments, a set of access classes or access identifiers may be considered to support SDT. For example, the potential access classes or access identifiers considered to support SDT may be 11-15 or any other suitable number.

[0040] In some alternative embodiments for condition 4), the terminal device 120 may determine a quality of service (QoS) parameter (i.e., 5QI) of the QoS flow of the service; and determine to transmit the uplink data in the inactive state based on the determination that the QoS parameter supports the transmission of the uplink data in the inactive state. In some embodiments, a 5QI value supporting SDT may be predefined. In some alternative embodiments, the 5QI value supporting SDT may be broadcast by system information from the network device 110. In some alternative embodiments, the 5QI value supporting SDT may be specifically configured to the terminal device 120 via an RRC message (e.g., an RRC release message or any other suitable message). In some alternative embodiments, a specific 5QI value for SDT may be introduced. For example, a potential 5QI value that may be considered to support SDT may be 66 or any other suitable number.

[0041] In some alternative embodiments for condition 4), the terminal device 120 may determine one or more data radio bearers (DRBs) for the service; and determine to transmit uplink data in an inactive state based on determining that the one or more DRBs support transmission of uplink data in an inactive state. In some embodiments, because the SDT is initiated for a UE in an inactive state, a DRB supporting the SDT may be found in the stored UE context, and the configuration for the SDT is based on the stored UE context. In some alternative embodiments, a DRB supporting the SDT may be configured during the RRC connected state, i.e., configured by an RRC reconfiguration message or any other suitable message. In some alternative embodiments, support for a DRB may be configured when the terminal device 120 is in an inactive state, for example, by an RRC release message or any other suitable message with a pause indication.

[0042] In some alternative embodiments for condition 4), the terminal device 120 may receive a first indication at the RRC layer of the terminal device 120 and from the non-access stratum (NAS) of the terminal device 120 regarding whether uplink data is to be transmitted in an inactive state; and determine whether uplink data is to be transmitted in an inactive state based on the first indication from the NAS layer.

[0043] As an additional embodiment of the above embodiment regarding condition 4), the terminal device 120 may also determine the size of the cache content associated with the service; and determine to transmit the uplink data in the inactive state based on determining that the size of the cache content is less than the threshold size. In some embodiments, the cache content may refer to the total uplink data and signaling available for transmission plus the MAC header and the MAC control element (CE) when necessary.

[0044] In some embodiments, the threshold size may be broadcast by system information from the network device 110. In some alternative embodiments, the threshold size may be a predetermined value. In some alternative embodiments, the threshold size for supporting SDT may be specifically configured to the terminal device 120 via an RRC message (e.g., an RRCRelease message).

[0045] The size of the cached content may be used in combination with one or more of the access category, access identifier, 5QI, and DRB. In some embodiments, different access categories, access identifiers, 5QIs, or DRBs may be associated with different values ​​of the threshold size. Thus, when the conditions for initiating SDT are met, the RRC layer of the terminal device 120 may initiate an SDT process instead of normal data transmission (hereinafter also referred to as NDT).

[0046] return Figure 2 In response to determining 201 that uplink data is to be transmitted in an inactive state, the terminal device 120 may restore 202 a radio bearer for transmission of uplink data in an inactive state. In some embodiments, the RRC layer of the terminal device 120 may restore one or more DRBs required to support transmission of uplink data in an inactive state. In addition, the RRC layer of the terminal device 120 may restore signaling radio bearer 1 (SRB1) and signaling radio bearer 2 (SRB2). Thereafter, the terminal device 120 may transmit uplink data in an inactive state based on the restored configuration.

[0047] The terminal device 120 may determine 203 whether configuration authorization information is stored for transmission of uplink data in the inactive state. Based on determining that the configuration authorization information is stored, the terminal device 120 may determine 204 whether a timing advance (TA) associated with the transmission of the uplink data is valid. Based on determining that the TA is valid, the terminal device 120 may transmit 205 the uplink data in the inactive state using the configuration authorization information.

[0048] According to the determination that no configuration authorization information is stored or the TA is invalid, the terminal device 120 may decide to transmit uplink data in an inactive state based on the random access procedure. For example, the RRC layer of the terminal device 120 may configure the lower layer (ie, the MAC layer) to perform SDT based on random access.

[0049] When transmitting uplink data based on the random access procedure, the terminal device 120 may determine 206 at the RRC layer whether subsequent transmission (i.e., subsequent SDT) is supported. In other words, the terminal device may determine whether only one SDT is supported or subsequent SDT is supported. In some embodiments, the RRC layer of the terminal device 120 may determine whether subsequent transmission is supported and then notify the lower layer (i.e., the MAC layer) whether subsequent transmission is supported. In some embodiments, the RRC layer may notify the MAC layer of a threshold size used in the initiation of the SDT for later comparison with the size of the buffer content associated with the uplink data.

[0050] In some embodiments, the RRC layer of the terminal device 120 may determine whether both the terminal device 120 and the network device 110 support subsequent transmission of uplink data. According to an embodiment of the present disclosure, two types of subsequent SDT may be supported: a subsequent SDT based on a configuration authorization and a subsequent SDT based on a dynamic authorization. A subsequent SDT based on a configuration authorization refers to uplink small data transmission on a pre-configured PUSCH resource (i.e., when the timing advance (TA) associated with the transmission is valid, the configuration authorization type 1 is reused). A subsequent SDT based on a dynamic authorization refers to uplink small data transmission on a dynamically scheduled PUSCH resource.

[0051] In some embodiments, the information about at least one of whether the network device 110 can support subsequent transmission and what types of subsequent transmission the network device 110 can support may be broadcast through system information from the network device 110. In some embodiments, the information about whether the terminal device 120 can support subsequent transmission and what types of subsequent transmission the terminal device 120 can support may be configured to the terminal device 120 by an RRC message (e.g., an RRC release message or any other suitable message) from the network device 110. In some embodiments, whether the subsequent transmission can be supported and what types of subsequent transmission can be supported may be associated with an access category, an access identifier, a 5QI, or a DRB.

[0052] According to determining that both the terminal device 120 and the network device 110 do not support the subsequent transmission, it is determined that the subsequent transmission is not supported.

[0053] In some additional embodiments, the terminal device 120 may also determine whether the service supports subsequent transmission of uplink data based on determining that both the terminal device 120 and the network device 110 support subsequent transmission. In some embodiments, the support of the service for subsequent transmission may be broadcast via system information from the network device 110. It should be noted that any other suitable forms are also feasible.

[0054] In some additional embodiments, based on determining that the service supports subsequent transmission of uplink data, the terminal device 120 may also determine the uplink resource configuration type for subsequent transmission supported by the service. For example, the terminal device 120 may determine whether the service supports dynamic authorization or supports configuration authorization. Based on determining that the terminal device does not support the uplink resource configuration type, the terminal device 120 may determine that subsequent transmission is not supported, and based on determining that the terminal device supports the uplink resource configuration type, the terminal device 120 may determine that subsequent transmission is supported.

[0055] Based on determining that the service does not support subsequent transmission, the terminal device 120 may determine that subsequent transmission is not supported.

[0056] Return again Figure 2 , upon determining that subsequent transmission is not supported and notifying the MAC layer that subsequent transmission is not supported (i.e., only one SDT is supported), the terminal device 120 may determine 207 at the MAC layer whether the size of the cache content associated with the service is greater than a threshold size. In some embodiments, the cache content may refer to the total uplink data and signaling available for transmission plus the MAC header and the MAC CE when necessary. The threshold size may be notified to the MAC layer by the RRC layer and may be compared with the reference Figure 2 Similar to that described in 210 .

[0057] Based on determining that the size of the cached content is less than or equal to the threshold size, the terminal device 120 may determine 208 whether there are dedicated resources whose size is greater than or equal to the threshold size. Based on determining that there are dedicated resources whose size is greater than or equal to the threshold size, the terminal device 120 may transmit 209 uplink data in an inactive state using the dedicated resources.

[0058] According to determining that the size of the cache content is greater than the threshold size or there is no dedicated resource whose size is greater than or equal to the threshold size, the terminal device 120 can cancel the transmission of the uplink data in the inactive state. In some embodiments, the MAC layer of the terminal device 120 can notify the upper layer (i.e., the RRC layer) that the SDT is canceled. In this way, NDT will be performed for the transmission of the uplink data.

[0059] In response to determining 206 that subsequent transmission is supported, the terminal device 120 may determine an uplink resource configuration for uplink data transmission and transmit uplink data on the uplink resource configuration. The determination and transmission may be performed in any suitable way.

[0060] In some additional embodiments of transmitting uplink data based on a random access procedure, the terminal device 120 may generate an RRC message indicating transmission of uplink data in an inactive state, and transmit the RRC message and the uplink data to the network device 110 during the random access procedure. For example, the terminal device 120 may set the recovery cause IE in the RRC connection recovery request (RRCConnectionResumeRequest) message to a new cause IE indicating SDT at the RRC layer, and submit the RRCConnectionResumeRequest message to the lower layer (i.e., the MAC layer) for the transmission. It should be noted that any other suitable form is also feasible.

[0061] In some alternative or additional embodiments of transmitting uplink data based on a random access procedure, the terminal device 120 may provide a MAC CE carrying an identifier of the terminal device 120 (e.g., an inactive radio network temporary identifier (I-RNTI)) from the RRC layer to a lower layer (i.e., a MAC layer) of the terminal device 120, and transmit the MAC CE and the uplink data to the network device 110 during the random access procedure. It should be noted that this is merely an example, and any other suitable form is also feasible.

[0062] Return again Figure 2 , upon receiving the uplink data, the network device 110 may transmit 210 a response to the reception of the uplink data. In some embodiments where subsequent transmission is not supported, the network device 110 may reply to the terminal device 120 with a first RRC message, which notifies the terminal device 120 to suspend the radio bearer used to transmit the uplink data in an inactive state. For example, the first RRC message may be an RRC release (RRCRelease) message. Alternatively, the first RRC message may be an RRC reject (RRCReject) message. It should be noted that any other suitable message is also feasible.

[0063] In some embodiments where anchor relocation occurs from a second network device (not shown) to network device 110, the first RRC message may include a pause configuration. The second network device is the network device that served terminal device 120 immediately before terminal device 120 changed from the connected state to the inactive state, i.e., the last served network device.

[0064] Upon receiving the first RRC message, the terminal device 120 may suspend 211 radio bearers used for transmitting uplink data in the inactive state. For example, the terminal device 120 may suspend one or more DRBs used for transmitting uplink data in the inactive state. In addition, the terminal device 120 may also suspend SRB1 and SRB2. In this way, the terminal device 120 returns to a normal inactive state without data transmission.

[0065] In some embodiments where subsequent transmission is supported, network device 110 may reply terminal device 120 with a second RRC message, which includes an uplink resource configuration for subsequent transmission. In some embodiments, uplink resource configuration may be associated with a dynamic authorization for subsequent transmission. In some alternative embodiments, uplink resource configuration may be associated with a configuration authorization for subsequent transmission. For example, the second RRC message may be an RRCRelease message. Alternatively, the second RRC message may be an RRCReject message. It should be noted that any other suitable message is also feasible.

[0066] In some embodiments where anchor relocation occurs from a second network device (not shown) to network device 110, the second RRC message may include a pause configuration. The second network device is the network device that served terminal device 120 before terminal device 120 changed from the connected state to the inactive state, i.e., the last served network device.

[0067] Upon receiving the second RRC message, the terminal device 120 may perform 212 subsequent transmission of uplink data in the inactive state using uplink resources. For example, the terminal device 120 may remain in the inactive state, maintain one or more currently activated SRBs and DRBs, maintain Packet Data Convergence Protocol (PDCP) state variables, and maintain security keys. In this way, the terminal device 120 may start subsequent transmissions.

[0068] Currently, for a terminal device 120 in an inactive state, if the terminal device 120 reselects from the first cell served by the network device 110 to the second cell served by the third network device (not shown) while the timer T319 is running (i.e., a RRCResumeRequest message is sent but no response is received), the terminal device 120 will enter an idle state. However, during the subsequent SDT, since there is no measurement and reporting mechanism, the network device 110 does not know that the terminal device 120 has moved to other cells, and may continue to allocate resources to the terminal device 120, especially in the case of a subsequent SDT based on configuration authorization, which results in a waste of radio resources.

[0069] In view of the above, embodiments of the present disclosure provide network control of SDT during state transition. In some embodiments in which cell reselection occurs during transmission of uplink data (first SDT) without receiving a response from network device 110, terminal device 120 may enter an idle state and retransmit the uplink data to a third network device.

[0070] In some embodiments in which cell reselection occurs during the transmission of uplink data based on the configuration authorization information or during the subsequent transmission of uplink data, the terminal device 120 may enter an idle state and release the uplink resource configuration for uplink data transmission in an inactive state. In some alternative embodiments, the terminal device 120 may stop subsequent transmissions but remain in an inactive state. In this case, the terminal device 120 may suspend the radio bearer used for uplink data transmission in an inactive state. For example, the terminal device 120 may suspend all SRBs and DRBs used for SDT except SRB0, and indicate PDCP suspension from the RRC layer to the lower layer (i.e., the MAC layer). In some embodiments, the terminal device 120 may also release the uplink resource configuration for the transmission of uplink data in an inactive state. In some embodiments, the terminal device 120 may further re-evaluate the validity of the SDT and re-initiate the SDT if necessary.

[0071] In some additional or alternative embodiments in which cell reselection occurs during transmission of uplink data based on the configuration grant information or during subsequent transmission of uplink data, the terminal device 120 may generate a second indication regarding the reselection and transmit the second indication to the network device 110. For example, the terminal device 120 may send a bye message to notify the network device 110 of the cell reselection, so that the network device 110 may stop providing uplink grants to the terminal device 120 for subsequent SDTs.

[0072] In some embodiments, the terminal device 120 may transmit the second indication via an RRC message. For example, the RRC message may be a UEAssistanceInfomation message or any other suitable message. In some alternative embodiments, the terminal device 120 may transmit the second indication via a MAC CE. For example, the MAC CE may have a fixed size of zero bits. It should be noted that any other appropriate form of the MAC CE is also feasible. In some alternative embodiments, the terminal device 120 may transmit the second indication via a physical (PHY) layer indication. For example, the terminal device 120 may use a dedicated scheduling request (SR) configuration to indicate a cell reselection during a subsequent SDT or an SDT based on a configuration authorization.

[0073] Typically, there are some situations where the terminal device 120 will change from an inactive state to an idle state. In some embodiments, when the terminal device 120 in an inactive state receives a core network (CN) paging, the terminal device 120 will change from an inactive state to an idle state. In some embodiments, in the case where RRCResume cannot be complied with, the terminal device 120 will change from an inactive state to an idle state. In some embodiments, when timer T319 is running, when timer T319 expires or an integrity check from a lower layer fails, the terminal device 120 will change from an inactive state to an idle state. In some embodiments, in the case of cell reselection while timer T319 or T302 is running, the terminal device 120 will change from an inactive state to an idle state. In some embodiments, when the terminal device 120 fails to trigger RNA due to AC blocking, the terminal device 120 will change from an inactive state to an idle state.

[0074] In these embodiments where the terminal device 120 changes from the inactive state to the idle state, the terminal device 120 may generate a third indication about the change, transmit the third indication to the network device 110, and release the uplink resource configuration for the transmission of uplink data in the inactive state. For example, the terminal device 120 may send a bye message to notify the network device 110 of the change so that the network device 110 may stop providing an uplink grant to the terminal device 120 for subsequent SDT. The third indication may be performed in a similar manner to the second indication, and its details are not repeated here.

[0075] By using the process described above, SDT can be well controlled. Corresponding to the process, the embodiment of the present disclosure also provides a communication method implemented at the terminal device and the network device respectively. Figures 3 to 9 This is described in more detail.

[0076] Figure 3 An example communication method 300 implemented at a terminal device according to some embodiments of the present disclosure is shown. For example, the method 300 may be implemented in a Figure 1 For the purpose of discussion, reference will be made to Figure 1 Method 300 is described. It should be understood that method 300 may include additional blocks not shown and / or may omit some of the blocks shown, and the scope of the present disclosure is not limited in this regard.

[0077] like Figure 3 As shown, at block 310, the terminal device 120 determines whether to transmit uplink data in the inactive state of the terminal device 120 based on the characteristics of the traffic associated with the uplink data. That is, the validity of the SDT is evaluated.

[0078] In some embodiments, the terminal device 120 can determine at least one of the access category and access identifier of the service, and determine to transmit the uplink data in the inactive state based on determining that at least one of the access category and the access identifier supports the transmission of uplink data in the inactive state.

[0079] In some alternative embodiments, the terminal device 120 may determine QoS parameters of the QoS flow of the service, and determine to transmit uplink data in the inactive state based on the determined QoS parameters supporting transmission of uplink data in the inactive state.

[0080] In some alternative embodiments, the terminal device 120 may determine one or more DRBs for the service, and determine to transmit uplink data in the inactive state based on determining that the one or more DRBs support transmission of uplink data in the inactive state.

[0081] In some alternative embodiments, the terminal device 120 may receive a first indication at the RRC layer of the terminal device 120 and from the NAS layer of the terminal device 120 regarding whether uplink data is to be transmitted in an inactive state, and determine whether uplink data is to be transmitted in an inactive state based on the first indication.

[0082] In some additional embodiments, the terminal device 120 may also determine the size of the cache content associated with the service, and determine to transmit uplink data in the inactive state based on determining that the size of the cache content is less than a threshold size. Figure 2 The description in 201 is similar, so it will not be repeated here.

[0083] At block 320, the terminal device 120 resumes the radio bearer for transmission of uplink data in the inactive state. In some embodiments, the terminal device 120 may resume one or more DRBs required to support uplink transmission in the inactive state. The operations at block 320 are similar to those of reference Figure 2 The operations described in 202 are similar, and other details are omitted here.

[0084] At block 330, when the terminal device 120 is in an inactive state, the terminal device 120 transmits uplink data to the network device 110 based on the configuration. Figure 4 Describe its details. Figure 4 An example method 400 for transmitting uplink data in an inactive state according to some embodiments of the present disclosure is shown. For example, the method 400 may be performed in a Figure 1 For the purpose of discussion, reference will be made to Figure 1Method 400 is described. It should be understood that method 400 may include additional blocks not shown and / or may omit some of the blocks shown, and the scope of the present disclosure is not limited in this regard.

[0085] like Figure 4 As shown, at block 410, the terminal device 120 may determine whether configuration authorization information is stored for transmission of uplink data in an inactive state. If it is determined that the configuration authorization information is stored, then at block 420, the terminal device 120 may determine whether the TA associated with the transmission of the uplink data is valid. If it is determined that the TA is valid, then at block 430, the terminal device 120 may transmit the uplink data in an inactive state using the configuration authorization information.

[0086] If it is determined at block 410 that no configuration authorization information is stored, or if it is determined at block 420 that the TA is invalid, then at block 440 the terminal device 1210 may transmit uplink data in an inactive state based on a random access procedure.

[0087] Figure 5 An example method 500 for transmitting uplink data based on a random access procedure according to some embodiments of the present disclosure is shown. For example, the method 500 may be performed in a Figure 1 For the purpose of discussion, reference will be made to Figure 1 Method 500 is described. It should be understood that method 500 may include additional blocks not shown and / or may omit some of the blocks shown, and the scope of the present disclosure is not limited in this regard. This embodiment considers whether subsequent SDT (also referred to herein as subsequent transmission) is supported and provides a corresponding network control scheme.

[0088] like Figure 5 As shown, at block 510, the terminal device 120 may determine at the RRC layer whether subsequent transmission of uplink data is supported. Figure 6 Describe its details. Figure 6 An example method 600 for determining whether to support subsequent transmission according to some embodiments of the present disclosure is shown. For example, the method 600 may be performed in the following manner: Figure 1 For the purpose of discussion, reference will be made to Figure 1 Method 600 is described. It should be understood that method 600 may include additional blocks not shown and / or may omit some of the blocks shown, and the scope of the present disclosure is not limited in this regard.

[0089] like Figure 6As shown, at block 610, terminal device 120 may determine whether both terminal device 120 and network device 110 support subsequent transmission of uplink data. If it is determined at block 610 that both terminal device 120 and network device 110 do not support subsequent transmission, the process may proceed to block 650. At block 650, terminal device 120 may determine that subsequent transmission is not supported.

[0090] If it is determined at block 610 that both the terminal device 120 and the network device 110 support subsequent transmission, the terminal device 120 may determine whether the service supports subsequent transmission at block 620. If it is determined at block 620 that the service does not support subsequent transmission, the process may also proceed to block 650. At block 650, the terminal device 120 may determine that subsequent transmission is not supported.

[0091] If it is determined at block 620 that the service supports subsequent transmission, then at block 630, the terminal device 120 may determine whether the terminal device 120 supports the uplink resource configuration type for the subsequent transmission supported by the service. If it is determined at block 630 that the terminal device 120 does not support the uplink resource configuration type, the process may also proceed to block 650. At block 650, the terminal device 120 may determine that subsequent transmission is not supported.

[0092] If it is determined at block 630 that the terminal device 120 supports the uplink resource configuration type, the terminal device 120 may determine at block 640 that subsequent transmission is supported. Figure 2 The description in 206 is similar, so it will not be repeated here.

[0093] It should be noted that Figure 6 The above examples are for illustration only and are not intended to limit the present disclosure. Any other suitable scheme for determining whether to support subsequent transmission is also feasible.

[0094] Return now Figure 5 , if it is determined at block 510 that subsequent transmission is not supported, then at block 520, the terminal device 120 may determine whether the size of the cache content associated with the service is greater than a threshold size. In some embodiments, the cache content may refer to the total uplink data and signaling available for transmission plus the MAC header and, if necessary, the MAC CE. In some embodiments, the cache content may refer to the total uplink data and signaling available for transmission plus the MAC header and, if necessary, the MAC CE. For details on the threshold size, refer to Figure 2 The description in 201 is similar and will not be repeated here.

[0095] If it is determined at block 520 that the size of the cache content associated with the service is not greater than the threshold size, i.e., less than or equal to the threshold size, then at block 530, the terminal device 120 may determine whether there are dedicated resources whose size is greater than or equal to the threshold size. If it is determined at block 530 that there are dedicated resources, then at block 540, the terminal device 120 may transmit uplink data in an inactive state.

[0096] If it is determined at block 530 that there are no dedicated resources of a size greater than or equal to the threshold size, or if it is determined at block 520 that the size of the cached content is greater than the threshold size, the process proceeds to block 550. At block 550, terminal device 120 may cancel transmission of uplink data in an inactive state.

[0097] If it is determined at block 510 that subsequent transmission is supported, then at block 560, the terminal device 120 may determine an uplink resource configuration for uplink data transmission, and at block 570, the terminal device 120 may transmit uplink data based on the uplink resource configuration. In some embodiments, the operations at blocks 560 and 570 may be performed by the above-described method 400. It should be noted that any other suitable method is also feasible.

[0098] In some embodiments, the terminal device 120 may receive a first RRC message from the network device 110, the first RRC message notifying the terminal device 120 to suspend a radio bearer for transmitting uplink data in an inactive state, and suspend the radio bearer in response to receiving the first RRC message. In some embodiments where anchor relocation occurs from the second network device to the network device 110, the RRC message may include a suspension configuration. The second network device is a network device that served the terminal device 120 immediately before the terminal device 120 changed from the connected state to the inactive state, i.e., the network device that last served the terminal device 120.

[0099] In some alternative embodiments, the terminal device 120 may receive a second RRC message from the network device, the second RRC message including an uplink resource configuration for subsequent transmission of uplink data, and perform the subsequent transmission in an inactive state using the uplink resource configuration.

[0100] In some embodiments in which the terminal device 120 reselects from the first cell served by the network device 110 to the second cell served by the third network device not shown during the transmission of the uplink data and does not receive a response to the transmission of the uplink data from the network device 110, the terminal device 120 may enter an idle state. In addition, the terminal device 120 may retransmit the uplink data to the third network device.

[0101] In some embodiments in which the terminal device 120 reselects from a first cell served by the network device 110 to a second cell served by a third network device during transmission of uplink data based on configuration authorization information or during subsequent transmission of uplink data, the terminal device 120 may enter an idle state and release the uplink resource configuration for transmission of uplink data in an inactive state.

[0102] In an alternative embodiment in which the terminal device 120 reselects from the first cell served by the network device 110 to the second cell served by the third network device during the transmission of uplink data based on the configuration authorization information or during the subsequent transmission of uplink data, the terminal device 120 may stop the subsequent transmission, suspend the radio bearer used for the uplink data transmission, and release the uplink resource configuration used for the transmission of the uplink data in the inactive state. In addition, the terminal device 120 may re-determine whether to transmit the uplink data in the inactive state, and re-initiate the transmission of the uplink data based on the re-determination to transmit the uplink data in the inactive state. For example, the terminal device 120 may repeat Figure 3 to re-evaluate the validity of the SDT and, if necessary, re-initiate the SDT.

[0103] In some alternative or additional embodiments in which the terminal device 120 reselects from a first cell served by the network device 110 to a second cell served by a third network device during transmission of uplink data based on configuration authorization information or during subsequent transmission of uplink data, the terminal device 120 may generate a second indication regarding the reselection and transmit the second indication to the network device 110.

[0104] In some embodiments in which the terminal device 120 changes from an inactive state to an idle state, the terminal device 120 may generate a third indication regarding the change, transmit the third indication to the network device 110, and release the uplink resource configuration for transmission of uplink data in the inactive state.

[0105] Utilizing the above-described SDT control scheme implemented at a terminal device, conditions for initiating SDT are defined, detailed RRC procedures when initiating SDT are provided, and UE behavior in the event of a cell reselection occurring during a subsequent SDT is also provided.

[0106] Hereinafter, an SDT control scheme implemented at a network device will be described. Figure 7 An example communication method 700 implemented at a network device according to some embodiments of the present disclosure is shown. For example, the method 700 may be implemented in a Figure 1 For the purpose of discussion, reference will be made to Figure 1 Method 700 is described. It should be understood that method 700 may include additional blocks not shown and / or may omit some of the blocks shown, and the scope of the present disclosure is not limited in this regard.

[0107] like Figure 7 As shown, in block 710, the network device 110 receives uplink data associated with the service. The uplink data is transmitted by the terminal device 120 in an inactive state based on the characteristics of the service. In some embodiments in which the network device 110 transmits configuration authorization information for transmission of the uplink data in an inactive state to the terminal device 120, the network device 110 may receive the uplink data based on the configuration authorization information.

[0108] In some embodiments, the network device 110 may receive uplink data and an RRC message from the terminal device 120 during the random access procedure. The RRC message may indicate that the uplink data is transmitted in an inactive state.

[0109] At block 720, the network device 110 may transmit a response to the reception of the uplink data to the terminal device 120. In some embodiments, the network device 110 may transmit a first RRC message in response, the first RRC message notifying the terminal device 120 to suspend a radio bearer used to transmit uplink data in an inactive state. In some embodiments in which an anchor relocation of the terminal device 120 occurs from a second network device to the network device, the first RRC message may include a suspension configuration. The second network device is a network device that served the terminal device immediately before the terminal device 120 changed from a connected state to an inactive state, i.e., the last served network device.

[0110] In some alternative embodiments, network device 110 may transmit a second RRC message in response, the second RRC message including an uplink resource configuration for subsequent transmission of uplink data. In some embodiments, the uplink resource configuration may be associated with a dynamic authorization subsequent SDT. In some alternative embodiments, the uplink resource configuration may be associated with a configuration authorization subsequent SDT. In some embodiments in which the anchor relocation of the terminal device 120 occurs from the second network device to the network device, the second RRC message may include a pause configuration. The second network device is a network device that serves the terminal device immediately before the terminal device 120 changes from a connected state to an inactive state, i.e., the last served network device.

[0111] In some additional embodiments, the network device 110 may transmit information about whether the network device 110 supports subsequent transmission of uplink data. For example, the network device 110 may broadcast the information via system information. Alternatively, the network device 110 may configure the information to the terminal device 120 via an RRC message.

[0112] At this point, a network response to the first SDT is provided. Figure 8 and Fig. 9 A description of the network control for the subsequent SDT is given. Figure 8 Another example communication method 800 implemented at a network device according to some embodiments of the present disclosure is shown. For example, the method 800 may be implemented in a Figure 1 For the purpose of discussion, reference will be made to Figure 1 Method 800 is described. It should be understood that method 800 may include additional blocks not shown and / or may omit some of the blocks shown, and the scope of the present disclosure is not limited in this regard. This embodiment describes the behavior during cell reselection.

[0113] like Figure 8 As shown, at box 810, the network device 110 may receive a second indication from the terminal device 120 during the transmission of uplink data based on the configuration authorization information or during the subsequent transmission of the uplink data, and the second indication is about the terminal device 120 reselecting from the first cell served by the network device 110 to the second cell served by the third network device (not shown). In some embodiments, the network device 110 may receive the second indication via an RRC message. In some alternative embodiments, the network device 110 may receive the second indication via a MAC CE. In some alternative embodiments, the network device 110 may receive the second indication via a PHY layer indication. Other details are similar to the details described in conjunction with the transmission of the second indication and are not repeated here.

[0114] In response to receiving the second indication, at block 820, the network device 110 may stop scheduling uplink resources to the terminal device 120 for subsequent transmission of uplink data. In this way, resource waste may be avoided.

[0115] Fig. 9 Another example communication method 900 implemented at a network device according to some embodiments of the present disclosure is shown. For example, the method 900 may be implemented in a Figure 1 For the purpose of discussion, reference will be made to Figure 1 Method 900 is described. It should be understood that method 900 may include additional blocks not shown and / or may omit some of the blocks shown, and the scope of the present disclosure is not limited in this regard. This embodiment describes the behavior when transitioning from an inactive state to an idle state.

[0116] like Fig. 9 As shown, in block 910, the network device 110 may receive from the terminal device 120 a third indication that the terminal device 120 has changed from an inactive state to an idle state. In some embodiments, the network device 110 may receive the third indication via an RRC message. In some alternative embodiments, the network device 110 may receive the third indication via a MAC CE. In some alternative embodiments, the network device 110 may receive the third indication via a PHY layer indication. Other details are similar to the details described in conjunction with the transmission of the third indication and are not repeated here.

[0117] In response to receiving the third indication, at block 920, the network device 110 may stop scheduling uplink resources to the terminal device 120 for subsequent transmission of uplink data. In this way, resource waste may be avoided.

[0118] With the above-described SDT control scheme implemented at the network device, a network response to the first SDT and subsequent SDTs is provided, and UE behavior in the case of cell reselection and state transition is also provided.

[0119] Fig.10 is a simplified block diagram of a device 1000 suitable for implementing an embodiment of the present disclosure. The device 1000 may be considered as Figure 1 Another example implementation of the network device 110 or the terminal device 120 is shown. Therefore, the device 1000 may be implemented at the first network device 110 or the terminal device 120, or implemented as at least a part of the first network device 110 or the terminal device 120.

[0120] As shown, the device 1000 includes a processor 1010, a memory 1020 coupled to the processor 1010, a suitable transmitter (TX) and receiver (RX) 1040 coupled to the processor 1010, and a communication interface coupled to the TX / RX 1040. The memory 1010 stores at least a portion of the program 1030. The TX / RX 1040 is used for bidirectional communication. The TX / RX 1040 has at least one antenna to facilitate communication, but in fact the access node mentioned in this application may have several antennas. The communication interface may represent any interface required for communication with other network elements, such as an X2 / Xn interface for bidirectional communication between eNB / gNB, an S1 / NG interface for communication between a mobility management entity (MME) / access and mobility management function (AMF) / SGW / UPF and an eNB / gNB, a Un interface for communication between an eNB / gNB and a relay node (RN), or a Uu interface for communication between an eNB / gNB and a terminal device.

[0121] Assume that program 1030 includes program instructions that, when executed by associated processor 1010, enable device 1000 to operate in accordance with embodiments of the present disclosure, as referred to herein. Figures 1 to 9 As discussed above. The embodiments herein may be implemented by computer software executable by a processor 1010 of the device 1000, or by hardware, or by a combination of software and hardware. The processor 1010 may be configured to implement various embodiments of the present invention. In addition, the combination of the processor 1010 and the memory 1020 may form a processing component 1050 suitable for implementing various embodiments of the present disclosure.

[0122] The memory 1020 may be of any type suitable for the local technology network and may be implemented using any suitable data storage technology, such as, as non-limiting examples, 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 1020 is shown in the device 1000, there may be several physically distinct memory modules in the device 1000. As non-limiting examples, the processor 1010 may be of any type suitable for the local technology network and may include 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 1000 may have multiple processors, such as a dedicated integrated circuit chip that is time-slave to a clock that synchronizes a main processor.

[0123] In general, various embodiments of the present disclosure may be implemented in hardware or dedicated circuits, software, logic, or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software, which may be executed by a controller, microprocessor, or other computing device. Although various aspects of the embodiments of the present disclosure are shown and described as block diagrams, flow charts, or using some other graphical representations, it will be understood that the blocks, devices, systems, techniques, or methods described herein may be implemented in hardware, software, firmware, dedicated circuits or logic, general hardware, or controllers or other computing devices, or some combination thereof, as non-limiting examples.

[0124] 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 those included in a program module that are executed in a device on a target real or virtual processor to perform the above-referenced Figures 2 to 9The process or method described. In general, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform specific tasks or implement specific abstract data types. The functions of program modules can be combined or separated between program modules as needed in various embodiments. The machine executable instructions of program modules can be executed in local or distributed devices. In distributed devices, program modules can be located in both local storage media and remote storage media.

[0125] The program code for executing the disclosed method can be written in any combination of one or more programming languages. These program codes can be provided to a processor or controller of a general-purpose computer, a special-purpose computer or other programmable data processing device so that the program code enables the function / operation specified in the flow chart and / or block diagram to be realized when the program code is executed by the processor or controller. The program code can be executed completely on the machine, partially on the machine, as an independent software package, partially on the machine and partially on a remote machine, or completely on a remote machine or server.

[0126] The above program code may be contained on a machine-readable medium, which may be any tangible medium that may contain or store a program used by or in conjunction with an instruction execution system, device, or apparatus. 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 electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or device, or any suitable combination of the foregoing. More specific examples of machine-readable storage media would include: an electrical connection with one or more wires, a portable computer disk, 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 disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0127] In addition, although operations are described in a particular order, this should not be understood as requiring the specific order shown or to perform these operations in sequence, or to perform all the operations shown, to achieve the desired result. In some cases, multitasking and parallel processing may be advantageous. Similarly, although several specific implementation details are included in the above discussion, these details should not be interpreted as limitations on the scope of the present disclosure, but should be interpreted as descriptions of features peculiar to a particular embodiment. Certain features described in the context of a separate embodiment may also be implemented in combination in a single embodiment. On the contrary, the various features described in the context of a single embodiment may also be implemented in multiple embodiments individually or in any suitable sub-combination.

[0128] Although the disclosure has been described in language specific to structural features and / or methodological actions, it should be understood that the disclosure defined in the appended claims is not necessarily limited to the specific features or actions described above. Instead, the specific features and actions described above are disclosed as example forms of implementing the claims.

Claims

1. A method of a terminal device, the method comprising: receiving a radio resource control (RRC) release message from a network device, the RRC release message including information indicating a data radio bearer (DRB) configured for small data transmission (SDT), the RRC release message including a suspension configuration; Determining to initiate a recovery procedure for the SDT in an inactive state based on a condition that the DRB configured for the SDT supports transmission of the first uplink data in an inactive state; Based on the suspension configuration, determine to suspend the DRB, the first signaling radio bearer SRB, and the second SRB configured for the SDT; Perform the recovery process for the DRB, the first SRB, and the second SRB; as well as The first uplink data is sent to the network device in the inactive state based on the DRB, the first SRB, and the second SRB.

2. The method of the terminal device according to claim 1, further comprising: determining a size of the first uplink data for the SDT, Wherein, based on a comparison between the size of the first uplink data for the SDT and a threshold, the terminal device determines to initiate the recovery procedure for the SDT.

3. The method of the terminal device according to claim 2, further comprising: System information is received from the network device, the system information including information indicating the threshold.

4. The method of the terminal device according to claim 3, further comprising: Determining whether configuration authorization information is configured for the SDT; Determining whether a timing advance (TA) associated with the SDT is valid according to determining that the configuration authorization information is configured for the SDT; In response to determining that the TA is valid, performing the recovery process for the SDT based on the configuration authorization information; as well as According to determining that the configuration authorization information is not configured or the TA is invalid, performing the recovery process for the SDT based on a random access process.

5. The method of the terminal device according to claim 1, further comprising: In response to reselecting from a first cell served by the network device to a second cell served by a second network device during the recovery procedure for the SDT, an idle state is entered.

6. The method of the terminal device according to claim 1, further comprising: Based on the configured authorization or dynamic authorization, subsequent transfers are performed.

7. A method for a network device, the method comprising: Sending a radio resource control (RRC) release message to a terminal device, the RRC release message including information indicating a data radio bearer (DRB) configured for small data transmission (SDT), the RRC release message including a suspension configuration, wherein based on a condition that the DRB configured for the SDT supports transmission of the first uplink data in an inactive state, a recovery procedure for the SDT in an inactive state is determined to be initiated, wherein the suspension configuration suspends the DRB, the first signaling radio bearer SRB and the second SRB configured for the SDT, and wherein the recovery process is performed for the DRB, the first SRB, and the second SRB; as well as Based on the DRB, the first SRB and the second SRB, the first uplink data in the inactive state is received from the terminal device. 8 . The method of the network device according to claim 7 , wherein the recovery procedure for the SDT is determined to be initiated based on a condition that the first uplink data is mapped to the radio bearer for the SDT.

9. The method of the network device according to claim 8, further comprising: System information is sent to the terminal device, where the system information includes information indicating a threshold.

10. The method of the network device according to claim 9, wherein the sending comprises: In response to determining that configuration authorization information is configured for the SDT and a timing advance (TA) associated with the SDT is valid, performing the recovery process for the SDT based on the configuration authorization information; as well as According to determining that the configuration authorization information is not configured or the TA is invalid, performing the recovery process for the SDT based on a random access process.

11. The method of the network device according to claim 7, wherein: In response to reselecting from a first cell served by the network device to a second cell served by a second network device during the recovery procedure for the SDT, the terminal device enters an idle state.

12. The method of the network device according to claim 7, further comprising: Receive subsequent transmissions based on configured authorization or dynamic authorization.

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