CN115175370A

CN115175370A - Method and device used for wireless communication

Info

Publication number: CN115175370A
Application number: CN202110368521.2A
Authority: CN
Inventors: 张锦芳; 张晓博
Original assignee: Shanghai Langbo Communication Technology Co Ltd
Current assignee: Shanghai Langbo Communication Technology Co Ltd
Priority date: 2021-04-06
Filing date: 2021-04-06
Publication date: 2022-10-11

Abstract

A method and apparatus used for wireless communication is disclosed. The first node maintains a first timer; transmitting a first message, the first message comprising RRC signaling; transitioning from an RRC inactive state to a first RRC state in response to expiration of the first timer; wherein the behavior maintenance first timer comprises: restarting the first timer in response to the number of data units of the first type transmitted after the last start of the first timer exceeding a first threshold; stopping the first timer in response to receiving a second message comprising RRC signaling, the second message used in response to the first message, if received; the first threshold is configurable or is a positive integer greater than 1. The method and the device realize failure detection during small data transmission.

Description

Method and device used for wireless communication

Technical Field

The present application relates to methods and apparatus in a wireless communication system, and more particularly, to methods and apparatus for supporting transmission of small data in an RRC inactive state in wireless communication.

Background

The RRC INACTIVE (RRC _ INACTIVE) state is a Radio Resource Control (RRC) state newly introduced in the NR (New Radio, new air interface). When the user enters the RRC inactive state, the user may retain part of the network configuration information. When a service arrives, the user may perform data transmission by re-entering an RRC CONNECTED (RRC _ CONNECTED) state. Up to Rel-16, data transmission in RRC inactive state is not supported in 3GPP (3 rd Generation Partner Project) RAN (Radio Access Network).

The application scenes of future wireless communication systems are more and more diversified, and with the rapid development of the internet of things, a small data service is an important service in future wireless communication. For small data transmission, the signaling overhead of RRC state transition is larger than the transmission overhead of small data, and the power consumption overhead of UE is also increased. Therefore, it is decided to initiate WI standardization work for small data transmissions in RRC inactive state on the 3gpp ran #88e omnibus.

Disclosure of Invention

The inventor finds out through research that the UE can transmit small data by using a random access procedure or configuring granted radio resources in an RRC inactive state, and in order to avoid failure of the small data transmission procedure due to system congestion or link failure, a failure detection mechanism needs to be defined so that the network and the UE can be consistent after the failure occurs.

In order to solve the above problem, the present application discloses a solution for detecting a small data transmission failure in an RRC inactive state, and a new timer is introduced to detect whether the small data transmission process fails by determining whether the timer expires, so as to obtain a beneficial effect of maintaining RRC state consistency between a network and a UE. Without conflict, embodiments and features in embodiments in a first node of the present application may apply to a second node and vice versa. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict. Further, although the present application was originally intended for the Uu air interface, the present application can also be used for the PC5 interface. Further, although the original purpose of the present application is to the terminal and base station scenario, the present application is also applicable to a V2X (Vehicle-to-electrical networking) scenario, a communication scenario between a terminal and a relay, and a communication scenario between a relay and a base station, and achieves similar technical effects in the terminal and base station scenario. Furthermore, adopting a unified solution for different scenarios (including but not limited to V2X scenarios and terminal to base station communication scenarios) also helps to reduce hardware complexity and cost. In particular, the terms (telematics), nouns, functions, variables in the present application may be explained (if not specifically stated) with reference to the definitions in the 3GPP specification protocols TS36 series, TS38 series, TS37 series.

The application discloses a method in a first node used for wireless communication, characterized by comprising:

maintaining the first timer;

transmitting a first message, the first message comprising RRC signaling; transitioning from an RRC inactive state to a first RRC state in response to expiration of the first timer;

wherein the behavior maintenance first timer comprises: restarting the first timer in response to the number of data units of the first type transmitted after the last start of the first timer exceeding a first threshold; stopping the first timer in response to receiving a second message comprising RRC signaling if the second message is received, the second message being used in response to the first message; the first RRC state is one of a first set of candidate states, the first set of candidate states including an RRC idle state; the first threshold is configurable or is a positive integer greater than 1.

As an embodiment, the present application is applicable to a small data transmission procedure in an RRC inactive state.

As an embodiment, the present application is applicable to a scenario in which small data is transmitted through a random access procedure.

As an embodiment, the present application is applicable to a scenario where small data is transmitted by configuring granted radio resources.

As an embodiment, the present application is applicable to an SDT (small data transmission) procedure in an RRC inactive state.

As an embodiment, the problem to be solved by the present application is: a failure detection mechanism for small data transmission procedures in RRC inactive state.

As an embodiment, the solution of the present application comprises: and introducing a new timer, and detecting whether the small data transmission process fails or not according to the expiration of the timer.

As an embodiment, the beneficial effects of the present application include: and realizing failure detection in the small data transmission process in the RRC inactive state.

As an embodiment, the beneficial effects of the present application include: transitioning from the RRC inactive state to the first RRC state when the first timer expires may maintain RRC state consistency between the network and the UE.

According to one aspect of the application, comprising:

in response to the number of data units of the first type transmitted after the last start of the first timer exceeding a first threshold, passing a first indication from the MAC sublayer to an upper layer;

wherein the first indication is used to trigger the action to restart the first timer, the number of data units of the first type being calculated at a MAC sub-layer.

As an embodiment, when there is a subsequent data transmission (subsequent data transmission) in the small data transmission process, restarting the first timer according to the amount of data transmitted may avoid interrupting the subsequent data transmission due to the first timer expiring to transition from the RRC inactive state to the first RRC state before the subsequent data transmission is completed.

As an embodiment, when there is subsequent data transmission in the small data transmission process, restarting the first timer according to the amount of data transmitted can avoid triggering the small data transmission process multiple times due to expiration of the first timer, thereby reducing signaling overhead and transmission delay.

As an embodiment, setting an expiration value of the first timer has design difficulty due to delay uncertainty of subsequent data transmission in a small data transmission process; this problem can be effectively solved by restarting the first timer by the amount of data transferred.

According to one aspect of the application, comprising:

the first timer is maintained at the RRC sublayer.

According to one aspect of the application, comprising:

receiving a third message;

wherein the receiving time of the third message is earlier than the sending time of the first message; the third message is used to enable transmission of a first set of radio bearers in the RRC inactive state; any one of the first type data units belongs to one of the first set of radio bearers.

According to one aspect of the application, comprising:

after receiving the third message and before sending the first message, receiving a first set of data units;

wherein the data volume of the first set of data units is not greater than a first threshold; any data unit in the first set of data units belongs to the first class of data units; the first node is in the RRC inactive state when sending the first message.

According to one aspect of the application, comprising:

the second message indicates an RRC state of the first node.

The application discloses a method in a second node used for wireless communication, characterized by comprising:

receiving a first message, the first message comprising RRC signaling;

wherein the first timer is maintained; in response to expiration of the first timer, the RRC inactive state is transitioned to a first RRC state; the first timer being maintained comprising: in response to the number of data units of the first type transmitted after the last start of the first timer exceeding a first threshold, the first timer is restarted; if a second message is received, the first timer is stopped in response to receiving the second message, the second message including RRC signaling, the second message being used in response to the first message; the first RRC state is one of a first set of candidate states, the first set of candidate states including an RRC idle state; the first threshold is configurable or is a positive integer greater than 1.

According to one aspect of the application, comprising:

in response to the number of data units of the first type transmitted after the last start of the first timer exceeding a first threshold, a first indication is passed from the MAC sublayer to the upper layer;

wherein the first indication is used to trigger the first timer to be restarted, the number of the first type of data units being calculated at a MAC sub-layer.

According to one aspect of the application, comprising:

the first timer is maintained at the RRC sublayer.

According to one aspect of the application, comprising:

sending a third message;

wherein the sending time of the third message is earlier than the receiving time of the first message; the third message is used to enable transmission of a first set of radio bearers in the RRC inactive state; any one of the first type data units belongs to one of the first set of radio bearers.

According to one aspect of the application, comprising:

after sending the third message and before receiving the first message, a first set of data units is received;

wherein the data volume of the first set of data units is not greater than a first threshold; any data unit in the first set of data units belongs to the first class of data units; a sender of the first message is in the RRC inactive state when sending the first message.

According to one aspect of the application, comprising:

the second message indicates an RRC state of the sender of the first message.

The application discloses a first node used for wireless communication, characterized by comprising:

a first receiver maintaining a first timer;

a first transmitter to transmit a first message, the first message comprising RRC signaling; transitioning from an RRC inactive state to a first RRC state in response to expiration of the first timer;

wherein the behavior maintenance first timer comprises: restarting the first timer in response to the number of data units of the first type transmitted after the last start of the first timer exceeding a first threshold; stopping the first timer in response to receiving a second message comprising RRC signaling, the second message used in response to the first message, if received; the first RRC state is one of a first set of candidate states, the first set of candidate states including an RRC idle state; the first threshold is configurable or is a positive integer greater than 1.

The present application discloses a second node for wireless communication, comprising:

a second receiver receiving a first message, the first message including RRC signaling;

wherein the first timer is maintained; in response to expiration of the first timer, the RRC inactive state is transitioned to a first RRC state; the first timer being maintained comprising: in response to the number of data units of the first class transmitted after the last start of the first timer exceeding a first threshold, the first timer is restarted; if a second message is received, the first timer is stopped in response to receiving the second message, the second message including RRC signaling, the second message being used in response to the first message; the first RRC state is one of a first set of candidate states, the first set of candidate states including an RRC idle state; the first threshold is configurable or is a positive integer greater than 1.

Drawings

Other features, objects and advantages of the present application will become more apparent upon reading of the following detailed description of non-limiting embodiments thereof, made with reference to the accompanying drawings in which:

fig. 1 illustrates a transmission flow diagram of a first node according to an embodiment of the present application;

FIG. 2 illustrates a schematic diagram of a network architecture according to one embodiment of the present application;

fig. 3 illustrates a schematic diagram of radio protocol architecture of a user plane and a control plane according to an embodiment of the present application;

FIG. 4 illustrates a hardware module diagram of a communication device according to an embodiment of the application;

FIG. 5 illustrates a wireless signal transmission flow diagram according to one embodiment of the present application;

fig. 6 illustrates an inter-layer message interaction diagram of the RRC sublayer and the MAC sublayer according to an embodiment of the present application;

FIG. 7 illustrates a process flow diagram of a first node according to one embodiment of the present application;

FIG. 8 illustrates a flow chart of a first timer according to one embodiment of the present application;

FIG. 9 illustrates a block diagram of a processing device in a first node according to one embodiment of the present application;

fig. 10 illustrates a block diagram of a processing device in a second node according to an embodiment of the application.

Detailed Description

The technical solutions of the present application will be further described in detail with reference to the accompanying drawings, and it should be noted that the embodiments and features of the embodiments of the present application can be arbitrarily combined with each other without conflict.

Example 1

Embodiment 1 illustrates a transmission flow diagram of a first node according to an embodiment of the present application, as shown in fig. 1.

In embodiment 1, a first node 100 sends a first message in step 101, the first message comprising RRC signaling; maintaining a first timer in step 102; transitioning from the RRC inactive state to the first RRC state in response to expiration of the first timer in step 103; wherein the behavior maintenance first timer comprises: restarting the first timer in response to the number of data units of the first type transmitted after the last start of the first timer exceeding a first threshold; stopping the first timer in response to receiving a second message comprising RRC signaling if the second message is received, the second message being used in response to the first message; the first RRC state is one of a first set of candidate states, the first set of candidate states including an RRC idle state; the first threshold is configurable or is a positive integer greater than 1.

For one embodiment, the first message is sent over an air interface.

For one embodiment, the air interface comprises an interface for wireless signal transmission.

For one embodiment, the air interface comprises an interface for wireless signaling.

For one embodiment, the air interface comprises Uu.

For one embodiment, the air interface includes a PC5.

For one embodiment, the first Message includes content in a MsgA (Message a) cache.

As an embodiment, the first Message comprises content in a Msg3 (Message 3 ) cache.

As an embodiment, the first message belongs to a Random Access (RA) procedure.

As an embodiment, the first message is a message 3 in a 4-step random access procedure.

As an embodiment, the first message is a message a in a 2-step random access procedure.

As an embodiment, the radio resource occupied by the first message is a Configuration Grant (CG).

As an embodiment, the first message includes a MAC (Medium Access Control) PDU (protocol data Unit).

As an embodiment, one MAC PDU includes at least one MAC sub-PDU (sub-PDU), the one MAC sub-PDU includes one MAC sub-header (sub-header), or the one MAC sub-PDU includes one MAC sub-header and one MAC SDU, or the one MAC sub-PDU includes one MAC sub-header and one MAC CE (Control Element), or the one MAC sub-PDU includes one MAC sub-header and padding (padding).

As an embodiment, the first message comprises only at least part of the bits of the first type of data unit.

As an embodiment, the first message comprises at least part of the bits of the first type of data unit.

For one embodiment, the first message includes RRC signaling.

As an embodiment, the first message includes RRC signaling and at least part of bits of the first type data unit.

As an embodiment, the first message includes at least two MAC SDUs, and the at least two MAC SDUs respectively include RRC signaling and at least part of bits of the first type data unit.

As an embodiment, the first message includes a BSR (Buffer Status Report).

As an embodiment, the RRC signaling included in the first message belongs to a Common Control Channel (CCCH).

As an embodiment, the RRC Signaling included in the first message belongs to SRB0 (Signaling Radio Bearer 0).

For one embodiment, the first message includes a RRCResumeRequest (RRC resume request).

For one embodiment, the first message includes RRCResumeRequestl (RRC resume request-long identity).

As an embodiment, when the first message includes RRCResumeRequest, the first message includes a resumeinity (continuation identity) field including 24 bits; when the first message includes RRCResumeRequestl, the resumediversity field included in the first message includes 40 bits.

As one embodiment, the first message includes a resumeCause field.

As an embodiment, the name of resumecuse included in the first message includes SDT (small data transmission).

For one embodiment, the resumecuse included in the first message is SDT.

As an embodiment, the second message includes a resume initial-SDT of mo (mobile originated) -SDT.

As an embodiment, the resumecuse included in the first Message is mo-SMS (Short Message Service).

As an embodiment, the resumecuse included in the first message is emergency.

As an embodiment, the resumecuse included in the first message is mt (mobile terminated) -SDT.

As an embodiment, the resumecuse included in the first message is mo-signalling.

For one embodiment, the first message includes an rrcreestablishrequest (RRC reestablishment request).

For one embodiment, the first message includes a ReestabilishmentCause field.

As an embodiment, the reseabattercause included in the first message is SDT.

As one embodiment, the first timer is maintained at an RRC sublayer of the first node.

As one embodiment, the behavior maintenance first timer includes: restarting the first timer in response to the number of data units of the first type transmitted after the last start of the first timer exceeding a first threshold.

As one embodiment, the phrase first type of data unit transmitted after a last start of the first timer includes: the first type of data unit transmitted through the MAC sublayer of the first node after a last start of the first timer.

As one embodiment, the phrase a first type of data unit transmitted after a last start of the first timer includes: the first type of data unit sent after the last start of the first timer.

As an embodiment, the first type of data unit sent only includes the first type of data unit sent for the first time.

As an embodiment, the transmitted data units of the first type include a first transmitted data unit of the first type and a retransmitted data unit of the first type.

As an embodiment, the first data unit of the first transmission of the phrase includes: the first type of data unit transmitted for the first time.

As an embodiment, the first data unit of the first transmission of the phrase comprises: k repeated transmissions (K repetitions) are configured for each first type of data unit, the first type of data unit being transmitted in a first transmission opportunity (first transmission opportunity) of the K transmission opportunities.

As an embodiment, the first data unit of the first transmission of the phrase includes: the first signaling indicates time-frequency resources occupied by a first wireless signal and a modulation coding mode adopted by the first wireless signal; a New Data Indicator (NDI) field (field) of the first signaling is inverted (toggled), indicating the first type of Data unit that is transmitted for the first time.

As one embodiment, the phrase retransmitted data units of the first category include: and the first type data unit is retransmitted after the first type data unit fails to be transmitted.

As one embodiment, the phrase retransmitted data units of the first category include: k repetition transmissions (Krepetition) are configured for each first type of data unit, the first type of data unit being transmitted in a transmission opportunity of the K transmission opportunities other than the first transmission opportunity.

As one embodiment, the phrase retransmitted data units of the first category include: the first signaling indicates time-frequency resources occupied by a first wireless signal and a modulation coding mode adopted by the first wireless signal; the NDI field of the first signaling is not inverted, indicating the retransmitted data unit of the first type.

As one embodiment, the phrase first type of data unit transmitted after a last start of the first timer includes: the first type of data unit that was transmitted or retransmitted after the last start of the first timer.

As one embodiment, the phrase first type of data unit transmitted after a last start of the first timer includes: the first type of data unit received after a last start of the first timer.

As one embodiment, the phrase first type of data unit transmitted after a last start of the first timer includes: the first type of data unit sent after the last start of the first timer and the first type of data unit received after the last start of the first timer.

As one embodiment, the phrase first type of data unit transmitted after a last start of the first timer includes: the first type of data unit that was transmitted or retransmitted after the last start of the first timer and the first type of data unit that was received after the last start of the first timer.

As one embodiment, the phrase that the number of data units of the first class transmitted after the last start of the first timer exceeds a first threshold comprises: the number of data units of a first type transmitted after a last start of the first timer is greater than a first threshold.

As one embodiment, the phrase that the number of data units of the first type transmitted after the last start of the first timer exceeds a first threshold includes: the number of data units of a first type transmitted after a last start of the first timer is equal to a first threshold.

As one embodiment, the phrase that the number of data units of the first class transmitted after the last start of the first timer exceeds a first threshold comprises: the number of data units of a first type transmitted after a last start of the first timer is not less than a first threshold.

As one embodiment, the first class data units transmitted after the last start of the first timer and before expiration do not exceed the first threshold, the first timer does not restart.

As one embodiment, the last start of the first timer includes one of a first start or a restart in a single SDT procedure.

As an embodiment, the one-time SDT procedure includes sending a first message including a random access procedure to which the first message belongs to the reception of the second message.

For one embodiment, the one-time SDT procedure includes initiating a random access procedure to which the first message belongs until the second message is received.

For one embodiment, the one-time SDT procedure includes sending the first message to receiving the second message.

As an embodiment, any of the data units of the first type includes at least one bit.

For one embodiment, any of the first type data units includes at least one byte.

As an embodiment, the first type of data unit includes a MAC SDU.

As an embodiment, the data units of the first type comprise MAC SDU segments (segments).

As an embodiment, the first type of data unit includes an RLC (Radio Link Control) SDU.

For one embodiment, the first type of data unit includes an RLC PDU.

As one embodiment, the number of data units of a first type transmitted after a most recent start of the first timer comprises Q1 bytes; and Q1 is 0, 1 or a positive integer greater than 1.

As an embodiment, said number of data units of a first type transmitted after a latest start of said first timer comprises Q2 MAC SDUs; and Q2 is 0, 1 or a positive integer greater than 1.

As an embodiment, said number of data units of the first type transmitted after the last start of said first timer is expressed in bytes (Byte).

As an embodiment, said number of data units of the first type transmitted after the last start of said first timer is expressed in bits (bits).

As an embodiment, said number of data units of the first type transmitted after the latest start of said first timer is expressed in bytes per second (Byte/s).

As an embodiment, said number of data units of the first type transmitted after the latest start of said first timer is expressed in number of mac sdus.

For one embodiment, the first threshold is configurable.

As an embodiment, the first threshold is configured by a network (configured).

As an embodiment, the first threshold is pre-configured (pre-configured).

As an embodiment, the first threshold is configured by a serving base station of the first node.

As an embodiment, the first threshold is configured by higher layer signaling.

As an embodiment, the first threshold is configured by an SIB (System Information Block).

As an embodiment, the first threshold is configured by SIB1 (system message block 1).

As an embodiment, the first threshold is configured by RRC signaling.

As an embodiment, the first threshold is carried in all or part of IE (Information Element) in RRC signaling.

As an embodiment, the first threshold is carried in a full or partial Field (Field) in an IE in RRC signaling.

As one embodiment, the first threshold is a fixed value.

As one embodiment, the first threshold is 0.

As an embodiment, the first threshold is 1.

As one embodiment, the first threshold is a positive integer greater than 1.

As one embodiment, the first threshold is expressed in bytes.

As an embodiment, the first threshold is represented in bits.

As an embodiment, the first threshold is expressed in bytes per second.

As an embodiment, the first threshold is expressed in terms of MAC SDUs.

As one example, the action resumes when the first timer occurs, the first timer is in a running state.

As one embodiment, the phrase restarting the first timer includes: the first timer starts to count time.

As an embodiment, after the first timer starts counting time and before the last time the counting time stops, the first timer is in a running state.

As an embodiment, after the first timer starts counting and before the last time expires, the first timer is in the running state.

As an embodiment, the first timer is counting, and the first timer is in the running state.

As an embodiment, after the first timer stops counting and before the last counting, the first timer is not in the running state.

As an embodiment, the first timer is not in the running state after the first timer expires and before the last time the first timer starts to count.

As one embodiment, the behavior maintenance first timer includes: stopping the first timer in response to receiving the second message if the second message is received.

For one embodiment, the second message is received over the air interface.

As an embodiment, the second message comprises RRC signaling, the second message being used in response to the first message.

As an embodiment, the second message is received at the RRC sublayer of the first node.

For one embodiment, the second message includes higher layer signaling.

For one embodiment, the second message includes rrcreelease (RRC release).

For one embodiment, the second message comprises a RRCReject (RRC reject).

For one embodiment, the second message includes RRCResume (RRC resume).

For one embodiment, the second message comprises a RRC setup.

In one embodiment, the second message is received in response to sending the first message.

As one embodiment, the first node is in the RRC inactive state after sending the first message and before receiving the second message.

As one embodiment, the first timer is stopped in response to receiving the second message.

As one embodiment, the phrase stopping the first timer comprises: the first timer stops counting.

As an embodiment, the first timer is in the running state when receiving the second message.

As an embodiment, if the second message is not received before the first timer expires, the second message is discarded from being received.

As an embodiment, the second message is discarded from being received if the first timer expires.

As an embodiment, when the first timer is not in the running state, the second message is discarded from being received.

As an embodiment, when the first timer is not in an active state, the serving base station of the first node abandons sending the second message.

As an embodiment, the first node transitions from the RRC inactive state to a first RRC state in response to expiration of the first timer.

As an embodiment, the first node is in the RRC inactive state when the first timer is running.

As an embodiment, the first RRC state is one candidate state of a first set of candidate states.

As one embodiment, the first RRC state is the RRC IDLE (RRC IDLE) state.

As one embodiment, the first RRC state is the RRC inactive state.

As an embodiment, the first RRC state is the RRC connected state.

As one embodiment, the first set of candidate states includes the RRC idle state.

As one embodiment, the first set of candidate states includes the RRC connected state.

As one embodiment, the first set of candidate states includes the RRC inactive state.

As one embodiment, the first node transitions from the RRC inactive state to the RRC idle state in response to expiration of the first timer.

As an embodiment, the first node transitions from the RRC inactive state back to the RRC inactive state in response to expiration of the first timer.

As an embodiment, the first node transitions from the RRC inactive state to the RRC connected state in response to expiration of the first timer if the first message includes a rrcreestableblemarginrequest.

Example 2

Embodiment 2 illustrates a network architecture diagram according to an embodiment of the present application, as shown in fig. 2. Fig. 2 illustrates a diagram of a network architecture 200 for NR 5g, LTE (Long-Term Evolution, long Term Evolution) and LTE-a (Long-Term Evolution Advanced, enhanced Long Term Evolution) systems. The NR 5g, LTE or LTE-a network architecture 200 may be referred to as a 5GS (5G System)/EPS (Evolved Packet System) 200 or some other suitable terminology. The 5GS/EPS 200 may include one or more UEs (User Equipment) 201, ng-RANs (next generation radio access networks) 202,5gc (5G Core networks )/EPC (Evolved Packet Core) 210, hss (Home Subscriber Server)/UDM (Unified Data Management) 220, and internet services 230. The 5GS/EPS may interconnect with other access networks, but these entities/interfaces are not shown for simplicity. As shown, the 5GS/EPS provides packet switched services, however those skilled in the art will readily appreciate that the various concepts presented throughout this application may be extended to networks providing circuit switched services or other cellular networks. The NG-RAN includes NR node bs (gnbs) 203 and other gnbs 204. The gNB203 provides user and control plane protocol termination towards the UE 201. The gnbs 203 may be connected to other gnbs 204 via an Xn interface (e.g., backhaul). The gNB203 may also be referred to as a base station, a base transceiver station, a radio base station, a radio transceiver, a transceiver function, a Basic Service Set (BSS), an Extended Service Set (ESS), a TRP (Transmission Reception Point), or some other suitable terminology, and in an NTN (Non Terrestrial/satellite Network) Network, the gNB203 may be a satellite, an aircraft, or a ground station relayed through a satellite. The gNB203 provides the UE201 with an access point to the 5GC/EPC210. Examples of UEs 201 include a cellular phone, a smart phone, a Session Initiation Protocol (SIP) phone, a laptop, a Personal Digital Assistant (PDA), a satellite radio, a global positioning system, a multimedia device, a video device, a Digital audio player (e.g., MP3 player), a camera, a game console, a drone, an aircraft, a narrowband internet of things device, a machine type communication device, a land vehicle, an automobile, a vehicle mounted device, a vehicle mounted communication unit, a wearable device, or any other similar functioning device. Those skilled in the art may also refer to UE201 as a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless communication device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable terminology. The gNB203 is connected to the 5GC/EPC210 via an S1/NG interface. The 5GC/EPC210 includes MME (Mobility Management Entity)/AMF (Authentication Management Field)/SMF (Session Management Function) 211, other MME/AMF/SMF214, S-GW (serving Gateway)/UPF (User Plane Function) 212, and P-GW (Packet data Network Gateway)/UPF 213.MME/AMF/SMF211 is a control node that handles signaling between UE201 and 5GC/EPC210. In general, the MME/AMF/SMF211 provides bearer and connection management. All user IP (Internet Protocol) packets are transmitted through the S-GW/UPF212, and the S-GW/UPF212 itself is connected to the P-GW/UPF213. The P-GW provides UE IP address allocation as well as other functions. The P-GW/UPF213 is connected to the internet service 230. The internet service 230 includes an operator-corresponding internet protocol service, and may specifically include an internet, an intranet, an IMS (IP Multimedia Subsystem), and a PS (Packet Switching) streaming service.

As an embodiment, the UE201 corresponds to a first node in the present application.

As an embodiment, the NR node B203 corresponds to a second node in the present application.

As an example, the gNB203 is a macro Cell (Marco Cell) base station.

As an embodiment, the gNB203 is a Micro Cell (Micro Cell) base station.

As an embodiment, the gNB203 is a Pico Cell (Pico Cell) base station.

As an embodiment, the gNB203 is a home base station (Femtocell).

As an embodiment, the gNB203 is a base station device supporting a large delay difference.

As an example, the gNB203 is a flight platform device.

As an embodiment, the gNB203 is a satellite device.

As an embodiment, the gNB203 is a testing device (e.g., a transceiver simulating a function of a base station part, a signaling tester).

As an embodiment, the radio link from the UE201 to the gNB203 is an uplink, which is used to perform uplink transmissions.

As an embodiment, the radio link from the gNB203 to the UE201 is a downlink, which is used to perform downlink transmission.

As an embodiment, the wireless link between the UE201 and the UE241 is a sidelink, which is used to perform sidelink transmissions.

As an embodiment, the UE201 and the gNB203 are connected via a Uu air interface.

As an embodiment, the UE201 and the UE241 are connected through a PC5 air interface.

Example 3

Embodiment 3 illustrates a schematic diagram of radio protocol architecture of a user plane and a control plane according to an embodiment of the present application, as shown in fig. 3. Fig. 3 is a schematic diagram illustrating an embodiment of radio protocol architecture for the user plane 350 and the control plane 300, fig. 3 showing the radio protocol architecture of the control plane 300 for the UE and the gNB in three layers: layer 1, layer 2 and layer 3. Layer 1 (L1 layer) is the lowest layer and implements various PHY (physical layer) signal processing functions. The L1 layer will be referred to herein as PHY301. Layer 2 (L2 layer) 305 is above PHY301, and is responsible for the link between the UE and the gNB through PHY301. The L2 layer 305 includes a MAC (Medium Access Control) sublayer 302, an RLC (Radio Link Control) sublayer 303, and a PDCP (Packet Data Convergence Protocol) sublayer 304, which terminate at the gbb on the network side. The PDCP sublayer 304 provides data ciphering and integrity protection, and the PDCP sublayer 304 also provides handover support for UEs between the gnbs. The RLC sublayer 303 provides segmentation and reassembly of packets, retransmission of lost packets by ARQ, and duplicate packet detection and protocol error detection. The MAC sublayer 302 provides mapping between logical and transport channels and multiplexing of logical channel identities. The MAC sublayer 302 is also responsible for allocating various radio resources (e.g., resource blocks) in one cell among the UEs. The MAC sublayer 302 is also responsible for HARQ (Hybrid Automatic Repeat Request) operations. A RRC (Radio Resource Control) sublayer 306 in layer 3 (L3 layer) in the Control plane 300 is responsible for obtaining Radio resources (i.e., radio bearers) and configuring the lower layers using RRC signaling between the gNB and the UE. The radio protocol architecture of the user plane 350 includes layer 1 (L1 layer) and layer 2 (L2 layer), the radio protocol architecture in the user plane 350 is substantially the same for the physical layer 351, the PDCP sublayer 354 in the L2 layer 355, the RLC sublayer 353 in the L2 layer 355 and the MAC sublayer 352 in the L2 layer 355 as the corresponding layers and sublayers in the control plane 300, but the PDCP sublayer 354 also provides header compression for upper layer packets to reduce radio transmission overhead. The L2 layer 355 in the user plane 350 further includes a Service Data Adaptation Protocol (SDAP) sublayer 356, and the SDAP sublayer 356 is responsible for mapping between QoS (Quality of Service) streams and Data Radio Bearers (DRBs) to support diversity of services. The radio protocol architecture of the UE in the user plane 350 may include some or all of the protocol sublayers including the SDAP sublayer 356, the pdcp sublayer 354, the rlc sublayer 353, and the MAC sublayer 352 at the L2 layer. Although not shown, the UE may also have several upper layers above the L2 layer 355, including a network layer (e.g., IP layer) that terminates at the P-GW on the network side and an application layer that terminates at the other end of the connection (e.g., far end UE, server, etc.).

As an embodiment, the entities of the sub-layers of the control plane in fig. 3 constitute an SRB (Signaling Radio Bearer) in the vertical direction.

As an embodiment, the entities of the sub-layers of the control plane in fig. 3 constitute a DRB (Data Radio Bearer) in the vertical direction.

As an example, the wireless protocol architecture in fig. 3 is applicable to the first node in the present application.

As an example, the wireless protocol architecture in fig. 3 is applicable to the second node in the present application.

As an embodiment, the first message in this application is generated in the MAC302 or the MAC352.

As an embodiment, the first message in this application is generated in the RRC306.

As an embodiment, the second message in this application is generated in the MAC302 or the MAC352.

As an embodiment, the second message in this application is generated in the RRC306.

As an embodiment, the third message in this application is generated in the RRC306.

As an embodiment, the first set of data units in this application is generated in the MAC302 or the MAC352.

As an example, the

L2 layer

305 or 355 belongs to a higher layer.

As an embodiment, the RRC sublayer 306 in the L3 layer belongs to a higher layer.

Example 4

Embodiment 4 illustrates a hardware module schematic diagram of a communication device according to an embodiment of the present application, as shown in fig. 4. Fig. 4 is a block diagram of a first communication device 450 and a second communication device 410 communicating with each other in an access network.

The first communications device 450 includes a controller/processor 459, a memory 460, a data source 467, a transmit processor 468, a receive processor 456, a multiple antenna transmit processor 457, a multiple antenna receive processor 458, a transmitter/receiver 454, and an antenna 452.

The second communication device 410 includes a controller/processor 475, a memory 476, a data source 477, a receive processor 470, a transmit processor 416, a multiple antenna receive processor 472, a multiple antenna transmit processor 471, a transmitter/receiver 418, and an antenna 420.

In transmission from the second communication device 410 to the first communication device 450, at the second communication device 410, an upper layer data packet from a core network or an upper layer data packet from a data source 477 is provided to the controller/processor 475. The core network and data source 477 represents all protocol layers above the L2 layer. The controller/processor 475 implements the functionality of the L2 layer. In transmissions from the second communications device 410 to the first communications device 450, the controller/processor 475 provides header compression, encryption, packet segmentation and reordering, multiplexing between logical and transport channels, and radio resource allocation to the first communications device 450 based on various priority metrics. The controller/processor 475 is also responsible for retransmission of lost packets, and signaling to the first communication device 450. The transmit processor 416 and the multi-antenna transmit processor 471 implement various signal processing functions for the L1 layer (i.e., the physical layer). The transmit processor 416 implements coding and interleaving to facilitate Forward Error Correction (FEC) at the second communication device 410, as well as mapping of signal constellation based on various modulation schemes (e.g., binary Phase Shift Keying (BPSK), quadrature Phase Shift Keying (QPSK), M-phase shift keying (M-PSK), M-quadrature amplitude modulation (M-QAM)). The multi-antenna transmit processor 471 performs digital spatial precoding, including codebook-based precoding and non-codebook based precoding, and beamforming processing on the coded and modulated symbols to generate one or more spatial streams. Transmit processor 416 then maps each spatial stream to subcarriers, multiplexes with reference signals (e.g., pilots) in the time and/or frequency domain, and then uses an Inverse Fast Fourier Transform (IFFT) to generate the physical channels carrying the time-domain multicarrier symbol streams. The multi-antenna transmit processor 471 then performs analog precoding/beamforming operations on the time domain multi-carrier symbol stream. Each transmitter 418 converts the baseband multicarrier symbol stream provided by the multi-antenna transmit processor 471 into a radio frequency stream that is then provided to a different antenna 420.

In a transmission from the second communications apparatus 410 to the first communications apparatus 450, each receiver 454 receives a signal through its respective antenna 452 at the first communications apparatus 450. Each receiver 454 recovers information modulated onto a radio frequency carrier and converts the radio frequency stream into a baseband multi-carrier symbol stream that is provided to a receive processor 456. Receive processor 456 and multi-antenna receive processor 458 implement the various signal processing functions of the L1 layer. A multi-antenna receive processor 458 performs receive analog precoding/beamforming operations on the baseband multi-carrier symbol stream from the receiver 454. Receive processor 456 converts the baseband multicarrier symbol stream after the receive analog precoding/beamforming operation from the time domain to the frequency domain using a Fast Fourier Transform (FFT). In the frequency domain, the physical layer data signals and the reference signals to be used for channel estimation are demultiplexed by the receive processor 456, and the data signals are subjected to multi-antenna detection in the multi-antenna receive processor 458 to recover any spatial streams destined for the first communication device 450. The symbols on each spatial stream are demodulated and recovered at a receive processor 456 and soft decisions are generated. The receive processor 456 then decodes and deinterleaves the soft decisions to recover the upper layer data and control signals transmitted by the second communications device 410 on the physical channel. The upper layer data and control signals are then provided to a controller/processor 459. The controller/processor 459 implements the functions of the L2 layer. The controller/processor 459 may be associated with a memory 460 that stores program codes and data. Memory 460 may be referred to as a computer-readable medium. In transmissions from the second communications device 410 to the first communications device 450, the controller/processor 459 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover upper layer packets from the second communications device 410. The upper layer packet is then provided to all protocol layers above the L2 layer. Various control signals may also be provided to L3 for L3 processing.

In a transmission from the first communications device 450 to the second communications device 410, an upper layer data packet is provided at the first communications device 450 to the controller/processor 459 using a data source 467. The data source 467 represents all protocol layers above the L2 layer. Similar to the send function at the second communications apparatus 410 described in the transmission from the second communications apparatus 410 to the first communications apparatus 450, the controller/processor 459 performs header compression, encryption, packet segmentation and reordering, and multiplexing between logical and transport channels, performing L2 layer functions for the user plane and control plane. The controller/processor 459 is also responsible for retransmission of lost packets and signaling to said second communications device 410. A transmit processor 468 performs modulation mapping, channel coding, and digital multi-antenna spatial precoding by a multi-antenna transmit processor 457 including codebook-based precoding and non-codebook based precoding, and beamforming, and the transmit processor 468 then modulates the resulting spatial streams into multi-carrier/single-carrier symbol streams, which are provided to different antennas 452 via a transmitter 454 after analog precoding/beamforming in the multi-antenna transmit processor 457. Each transmitter 454 first converts the baseband symbol stream provided by the multi-antenna transmit processor 457 into a radio frequency symbol stream and provides the radio frequency symbol stream to the antenna 452.

In a transmission from the first communication device 450 to the second communication device 410, the functionality at the second communication device 410 is similar to the receiving functionality at the first communication device 450 described in the transmission from the second communication device 410 to the first communication device 450. Each receiver 418 receives an rf signal through its respective antenna 420, converts the received rf signal to a baseband signal, and provides the baseband signal to a multi-antenna receive processor 472 and a receive processor 470. The receive processor 470 and the multiple antenna receive processor 472 collectively implement the functionality of the L1 layer. The controller/processor 475 implements L2 layer functions. The controller/processor 475 can be associated with a memory 476 that stores program codes and data. Memory 476 may be referred to as a computer-readable medium. In transmission from the first communication device 450 to the second communication device 410, the controller/processor 475 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover upper layer packets from the first communication device 450. Upper layer data packets from the controller/processor 475 may be provided to all protocol layers above the core network or L2 layer and various control signals may also be provided to the core network or L3 for L3 processing.

As an embodiment, the first communication device 450 apparatus includes: at least one processor and at least one memory including computer program code; the at least one memory and the computer program code configured to, for use with the at least one processor, the first communication device 450 apparatus at least: maintaining the first timer; transmitting a first message, the first message comprising RRC signaling; transitioning from an RRC inactive state to a first RRC state in response to expiration of the first timer; wherein the behavior maintenance first timer comprises: restarting the first timer in response to the number of data units of the first type transmitted after the last start of the first timer exceeding a first threshold; stopping the first timer in response to receiving a second message comprising RRC signaling if the second message is received, the second message being used in response to the first message; the first RRC state is one of a first set of candidate states, the first set of candidate states including an RRC idle state; the first threshold is configurable or is a positive integer greater than 1.

As an embodiment, the first communication device 450 apparatus includes: a memory storing a program of computer readable instructions that when executed by at least one processor result in actions comprising: maintaining the first timer; transmitting a first message, the first message comprising RRC signaling; transitioning from an RRC inactive state to a first RRC state in response to expiration of the first timer; wherein the behavior maintenance first timer comprises: restarting the first timer in response to the number of data units of the first type transmitted after the last start of the first timer exceeding a first threshold; stopping the first timer in response to receiving a second message comprising RRC signaling if the second message is received, the second message being used in response to the first message; the first RRC state is one of a first set of candidate states, the first set of candidate states including an RRC idle state; the first threshold is configurable or is a positive integer greater than 1.

As an embodiment, the second communication device 410 apparatus includes: at least one processor and at least one memory including computer program code; the at least one memory and the computer program code are configured for use with the at least one processor. The second communication device 410 means at least: receiving a first message, the first message comprising RRC signaling; wherein the first timer is maintained; in response to expiration of the first timer, the RRC inactive state is transitioned to a first RRC state; the first timer being maintained comprising: in response to the number of data units of the first type transmitted after the last start of the first timer exceeding a first threshold, the first timer is restarted; if a second message is received, the first timer is stopped in response to receiving the second message, the second message including RRC signaling, the second message being used in response to the first message; the first RRC state is one of a first set of candidate states, the first set of candidate states including an RRC idle state; the first threshold is configurable or is a positive integer greater than 1.

As an embodiment, the second communication device 410 apparatus includes: a memory storing a program of computer readable instructions that when executed by at least one processor result in actions comprising: receiving a first message, the first message comprising RRC signaling; wherein the first timer is maintained; in response to expiration of the first timer, the RRC inactive state is transitioned to a first RRC state; the first timer is maintained comprising: in response to the number of data units of the first class transmitted after the last start of the first timer exceeding a first threshold, the first timer is restarted; if a second message is received, the first timer is stopped in response to receiving the second message, the second message including RRC signaling, the second message being used in response to the first message; the first RRC state is one of a first set of candidate states, the first set of candidate states including an RRC idle state; the first threshold is configurable or is a positive integer greater than 1.

As an embodiment, the first communication device 450 corresponds to a first node in the present application.

As an embodiment, the second communication device 410 corresponds to a second node in the present application.

For one embodiment, the first communication device 450 is a UE.

For one embodiment, the first communication device 450 is a relay node.

As an embodiment, the second communication device 410 is a base station device.

For one embodiment, the second communication device 410 is a relay node.

For one embodiment, at least one of the antenna 452, the transmitter 454, the multi-antenna transmit processor 457, the transmit processor 468, or the controller/processor 459 is configured to transmit a first message as described herein.

For one embodiment, at least one of the antenna 420, the receiver 418, the multi-antenna receive processor 472, the receive processor 470 or the controller/processor 475 is configured to receive a first message in the present application.

For one embodiment, at least one of the antenna 420, the transmitter 418, the multi-antenna transmit processor 471, the transmit processor 416 or the controller/processor 475 is configured to send the second message.

For one embodiment, at least one of the antenna 452, the receiver 454, the multi-antenna receive processor 458, the receive processor 456, or the controller/processor 459 is configured to receive a second message as described herein.

For one embodiment, at least one of the antenna 420, the transmitter 418, the multi-antenna transmit processor 471, the transmit processor 416 or the controller/processor 475 is configured to send the third message.

For one embodiment, at least one of the antenna 452, the receiver 454, the multi-antenna receive processor 458, the receive processor 456 or the controller/processor 459 is configured to receive the third message in this application.

For one embodiment, at least one of the antenna 452, the receiver 454, the multi-antenna receive processor 458, the receive processor 456 or the controller/processor 459 is configured to receive a first set of data units from the present application.

Example 5

Embodiment 5 illustrates a wireless signal transmission flow chart according to an embodiment of the present application, as shown in fig. 5. In fig. 5, a first node U51 and a second node N52 communicate over a wireless interface. It is specifically noted that the order in this example does not limit the order of signal transmission and the order of implementation in this application. Step F0 in the dashed box is optional.

ForFirst node U51Receiving a third message in step S511; receiving a first set of data units in step S512; transmitting a first message in step S513; maintaining the first timer in step S514; in step S515, connectAnd receiving a second message.

For theSecond node N52Transmitting a third message in step S521; receiving a first message in step S522; the second message is transmitted in step S523.

In example 5, the first timer is maintained; transmitting a first message, the first message comprising RRC signaling; transitioning from an RRC inactive state to a first RRC state in response to expiration of the first timer; wherein the behavior maintenance first timer comprises: restarting said first timer in response to the number of data units of the first type transmitted after the most recent start of said first timer exceeding a first threshold; stopping the first timer in response to receiving a second message comprising RRC signaling if the second message is received, the second message being used in response to the first message; the first RRC state is one of a first set of candidate states, the first set of candidate states including an RRC idle state; the first threshold is configurable, or the first threshold is a positive integer greater than 1; in response to the number of data units of the first type transmitted after the last start of the first timer exceeding a first threshold, passing a first indication from the MAC sublayer to an upper layer; wherein the first indication is used to trigger the action to restart the first timer, the number of data units of the first type being calculated at a MAC sub-layer; the first timer is maintained at the RRC sublayer; receiving a third message; wherein the receiving time of the third message is earlier than the sending time of the first message; the third message is used to enable transmission of a first set of radio bearers in the RRC inactive state; any first type data unit belongs to one radio bearer in the first radio bearer set; after receiving the third message and before sending the first message, receiving a first set of data units; wherein the data volume of the first set of data units is not greater than a first threshold; any data unit in the first set of data units belongs to the first class of data units; the first node is in the RRC inactive state when sending the first message; the second message indicates an RRC state of the first node.

As an embodiment, the first node U51 sends the data units of the first type after step S513 and before step S515.

As an embodiment, the first node U51 receives the data units of the first type after step S513 and before step S515.

As an embodiment, the first node U51 sends the data unit of the first type after step S513 and before step S515 and receives the data unit of the first type.

As an embodiment, the third message is received over an air interface.

As an embodiment, the third message is received at the RRC sublayer of the first node.

For one embodiment, the third message includes RRC signaling.

As an embodiment, the third message includes rrcreelease (RRC release).

As an embodiment, the third message comprises rrcreelease, and the rrcreelease comprises a SuspendConfig (suspend configuration) field therein; the third message indicates that the first node is in the RRC inactive state.

In one embodiment, the third message includes radio resources granted by the configuration occupied by the first message.

As one embodiment, the third message instructs the first node to enter the RRC inactive state.

As one embodiment, the third message indicates the first node to transition from the RRC connected state to the RRC inactive state.

As one embodiment, the third message indicates the first node to transition from the RRC inactive state back to the RRC inactive state.

As one embodiment, the third message indicates that the first node transitioned from the RRC idle state to the RRC inactive state.

As an embodiment, the first timer is established when the third message indicates the first node to transition from the RRC connected state to the RRC inactive state.

As an embodiment, the first timer is established when the third message indicates that the first node transitioned from the RRC idle state to the RRC inactive state.

As one embodiment, the first timer is established (Setup) only when the first node is in the RRC inactive state.

As an embodiment, the first timer is released (Release) when the first node is in the RRC idle state or the RRC connected state.

As an embodiment, the first timer is only run when the first node is in the RRC inactive state.

As an embodiment, the time of reception of the third message is earlier than the time of transmission of the first message.

As an embodiment, the receiving time of the third message is earlier than the initiating time of the random access procedure to which the first message belongs.

As an embodiment, the receiving time of the third message is earlier than the sending time of the Msg1 included in the random access procedure to which the first message belongs.

As an embodiment, the receiving time of the third message is earlier than the sending time of MsgA included in the random access procedure to which the first message belongs.

As one embodiment, the third message is used to enable transmission of the first set of radio bearers in the RRC inactive state.

As one embodiment, the phrase that the third message is used to enable transmission of the first set of radio bearers in the RRC inactive state includes: the third message indicates that the first set of radio bearers is to transmit in the RRC inactive state when a first set of conditions is satisfied.

As one embodiment, the first set of conditions includes at least one condition.

As an embodiment, the first set of conditions includes only that an amount of data of the first set of radio bearers buffered before the first message is sent is not greater than a first threshold.

For an embodiment, the first set of conditions includes only that an amount of data of the first set of radio bearers buffered before the first message is sent is less than a first threshold.

As one embodiment, the first set of conditions includes an amount of data of the first set of radio bearers transmitted after sending the first message and before receiving the second message being not greater than a first threshold.

As one embodiment, the first set of conditions includes an amount of data of the first set of radio bearers transmitted after sending the first message and before receiving the second message being less than a first threshold.

For one embodiment, the first set of conditions includes uplink synchronization with a recipient of the first message prior to sending the first message.

As one embodiment, the first set of conditions includes a Reference Signal Received Power (RSRP) of the receiver of the first message measured by a sender of the first message being not less than a second threshold; the second threshold is configured by the network, or preconfigured.

As an embodiment, the first set of conditions includes at least a first condition among three conditions that the data volume of the first set of radio bearers buffered before the first message is sent is not greater than a first threshold, uplink synchronization is performed with a receiver of the first message before the first message is sent, or RSRP of the receiver of the first message measured by a sender of the first message is not less than a second threshold.

As an embodiment, the first set of conditions includes at least a first condition of three conditions that the data volume of the first set of radio bearers buffered before the first message is sent is less than a first threshold, uplink synchronization with a receiver of the first message before the first message is sent, or RSRP of the receiver of the first message measured by a sender of the first message is not less than a second threshold.

As an embodiment, the first set of radio bearers transmits in the RRC inactive state when all conditions in the first set of conditions are met.

As an embodiment, the first set of radio bearers is transmitted in the RRC connected state when any one of the first set of conditions is not satisfied.

As an embodiment, the third message comprises a domain name comprising an SDT.

For one embodiment, the third message indicates the first set of radio bearers; the first set of radio bearers includes at least one radio bearer.

As an embodiment, the third message includes a first set of radio bearer identities, the first set of radio bearer identities including at least one radio bearer identity; any radio bearer identification in the first set of radio bearer identifications indicates one radio bearer in the first set of radio bearers.

As an embodiment, any one of the first set of Radio bearers is a Data Radio Bearer (DRB).

As an embodiment, any one of the first set of radio bearers includes a PDCP (Packet Data Convergence Protocol) bearer.

As an embodiment, any radio bearer in the first set of radio bearers comprises an RLC bearer.

As an embodiment, any radio bearer in the first set of radio bearers comprises an RLC channel (channel).

As an embodiment, any data unit of the first type belongs to one radio bearer in the first set of radio bearers.

As an embodiment, any data unit of the first type is transmitted over one radio bearer in the first set of radio bearers.

As one embodiment, after receiving the third message and before sending the first message, a first set of data units is received.

As one embodiment, the first set of data units is received after receiving the third message and before initiation of a random access procedure to which the first message belongs.

As one embodiment, the first set of data units is received after receiving the third message and before a Msg1 send included in a random access procedure to which the first message belongs.

As one embodiment, the first set of data units is received after receiving the third message and before a MsgA send comprised by a random access procedure to which the first message belongs.

As one embodiment, the first set of data units is received after receiving the third message and before initiation of an SDT process to which the first message belongs.

As an embodiment, the first message is a first message including the data unit of the first type sent after receiving the third message.

As an embodiment, the first set of data units is received from an upper layer of the first node; the upper layer is an NAS layer.

For one embodiment, the first set of data units is received over an air interface.

As an embodiment, the first set of data units comprises at least one data unit.

As an embodiment, any data unit in the first set of data units belongs to the first class of data units.

As an embodiment, any data unit of the first set of data units belongs to one radio bearer of the first set of radio bearers.

As an embodiment, a data volume (data volume) of the first set of data units is not greater than a first threshold.

As an embodiment, the amount of data of the first set of data units is smaller than the first threshold.

As one embodiment, the amount of data of the first set of data units includes at least one bit.

As one embodiment, the amount of data of the first set of data units includes at least one byte.

As an embodiment, the first set of data units includes all currently buffered data units.

As an embodiment, the first set of data units comprises all data units currently buffered at the MAC sublayer.

As an embodiment, the first set of data units comprises all data units currently buffered in the MAC sublayer and the RLC sublayer.

As an embodiment, the first set of data units includes all data units currently buffered in the MAC sublayer, the RLC sublayer and the PDCP sublayer.

As an embodiment, the data amount of the first data unit set includes a value obtained by dividing the number of bits of all bits included in the first data unit set by 8.

As an embodiment, the amount of data of the first set of data units is expressed in bytes.

For one embodiment, the first threshold is configured by a network.

As an embodiment, the first threshold is pre-configured.

As an embodiment, the first threshold is a fixed value.

As an embodiment, the first threshold is standard defined (specified).

For one embodiment, the first threshold is configured by a SIB.

As an embodiment, the first threshold is configured by SIB 1.

As an embodiment, the first threshold is configured by RRC signaling.

As an embodiment, the first threshold is expressed in bytes.

In one embodiment, the first message is sent in response to receiving the first set of data units.

As an embodiment, a random access procedure comprising the first message is triggered in response to receiving the first set of data units.

As an embodiment, an SDT procedure is triggered in response to receiving the first set of data units.

As an embodiment, the first node is in the RRC inactive state when sending the first message; the first message comprises at least part of the bits of at least one data unit of a first type comprised by the first set of data units.

As an embodiment, the last start of the first timer is accompanied by the first message.

As one embodiment, the phrase first type of data unit transmitted after a last start of the first timer includes: the first type of data unit transmitted after the last start of the first timer comprises the first type of data unit comprised by the first message; wherein the most recent start of the first timer is accompanied by the first message.

As one embodiment, the behavior maintenance first timer includes: the first timer is started with the first message.

As one embodiment, the phrase accompanying the first message, starting the first timer includes: sending the first message and starting the first timer is not detachable (atomic).

As one embodiment, the phrase accompanying the first message, starting the first timer comprises: sending the first message and starting the first timer are concomitant to each other.

As one embodiment, the phrase accompanying the first message, starting the first timer comprises: sending the first message is used to trigger starting the first timer.

As one embodiment, the phrase accompanying the first message, starting the first timer comprises: starting the first timer when the first message is sent (uplink transmission of the first message).

As one embodiment, the phrase accompanying the first message, starting the first timer includes: the first timer is started Following the transmission of the first message.

As one embodiment, the phrase accompanying the first message, starting the first timer includes: the first message is sent immediately following the start of the first timer.

As one embodiment, the phrase accompanying the first message, starting the first timer comprises: and starting the first timer when a random access process (uplink initiation of the procedure) to which the first message belongs is initiated.

As one embodiment, the phrase accompanying the first message, starting the first timer comprises: the first timer is started immediately after the random access procedure to which the first message belongs is initiated.

As one embodiment, the phrase accompanying the first message, starting the first timer comprises: and initiating a random access process to which the first message belongs immediately after starting the first timer.

As one embodiment, the phrase accompanying the first message, starting the first timer comprises: starting the first timer when a Small Data Transmission (SDT) process to which the first message belongs is initiated.

As one embodiment, the phrase accompanying the first message, starting the first timer comprises: the first timer is started immediately following initiation of a Small Data Transmission (SDT) process to which the first message belongs.

As one embodiment, the phrase accompanying the first message, starting the first timer includes: initiating a Small Data Transmission (SDT) process to which the first message belongs immediately after starting the first timer.

As one embodiment, the phrase accompanying the first message, starting the first timer comprises: starting said first timer when a first one of said first type of data units is sent after sending said first message.

As one embodiment, the phrase accompanying the first message, starting the first timer includes: starting the first timer upon receiving a first one of the first type of data units after sending the first message.

As one embodiment, the phrase accompanying the first message, starting the first timer includes: sending the first message is not used to start a T319 timer.

As an example, transmitting the first type of data unit is not used to start or restart the T319.

As an embodiment, the first timer is started along with the first message, the first message comprising at least a part of bits of at least one data unit of the first type; the T319 timer is started with a fourth message, which does not include the data unit of the first type.

As an example, the running times of the first timer and the T319 timer are orthogonal.

As an embodiment, the fourth message includes RRC signaling.

For one embodiment, the fourth message includes RRCResumeRequest (RRC resume request).

As an embodiment, the fourth message includes RRCResumeRequestl (RRC continuation request-long identity).

As an embodiment, the MAC SDU included in the fourth message includes only RRC signaling.

In one embodiment, the MAC SDU included in the fourth message includes only CCCH.

As an embodiment, the random access procedure to which the first message belongs is used for SDT transmission; the random access procedure to which the fourth message belongs is used for functions other than SDT transmission.

As an embodiment, the random access procedure to which the fourth message belongs is used for initial access (initial access) from an RRC idle state.

As an embodiment, the random access procedure to which the fourth message belongs is used for an RRC connection reestablishment (re-establishment) procedure.

As an embodiment, the random access procedure to which the fourth message belongs is used to implement uplink synchronization.

As an embodiment, the random access procedure to which the fourth message belongs is used to obtain uplink transmission resources.

As an embodiment, the random access procedure to which the fourth message belongs is used for Scheduling Request (SR) failure.

As an embodiment, a random access procedure to which the fourth message belongs is used for handover.

As an embodiment, the random access procedure to which the fourth message belongs is used to transition the RRC state from the RRC inactive state.

As an embodiment, the random access procedure to which the fourth message belongs is used to establish time alignment (time alignment) with TAG (Timing Advance Group).

As an embodiment, the random access procedure to which the fourth message belongs is used to obtain other system information.

As an embodiment, the random access procedure to which the fourth message belongs is used for beam failure recovery.

As an embodiment, the random access procedure to which the fourth message belongs is used for persistent uplink LBT (Listen Before Talk) failure on a SpCell (Special Cell).

As one embodiment, the phrase starting the first timer comprises: the first timer starts to count time.

As an embodiment, the number of data units of the first type transmitted after the last start of the first timer is calculated at the MAC sublayer.

As an embodiment, a first indication is passed from the MAC sublayer to an upper layer in response to the number of data units of the first type transmitted after a last start of the first timer exceeding the first threshold; the upper layer is an RRC sublayer; the MAC sublayer and the RRC sublayer both belong to the first node.

As an embodiment, the RRC sublayer of the first node receives the first indication; the first indication is used to trigger the action to restart the first timer.

As an embodiment, the second message includes rrcreelease, and the SuspendConfig field is not included in the rrcreelease; the second message indicates that the RRC state of the first node is the RRC idle state.

As one embodiment, the second message includes rrcreelease, and the rrcreelease includes a suspenndconfig field therein; the second message indicates that the RRC state of the first node is the RRC inactive state.

As one embodiment, the second message includes RRCReject; the second message indicates that the RRC state of the first node is the RRC idle state.

As an embodiment, the second message comprises RRCResume; the second message indicates that the RRC state of the first node is an RRC connected state.

As one embodiment, the second message comprises a RRCSetup; the second message indicates that the RRC state of the first node is the RRC connected state.

For one embodiment, the second message comprises RRCReestablishment; the second message indicates that the RRC state of the first node is the RRC connected state.

As an embodiment, when the second message indicates that the RRC state of the first node is the RRC connected state, the first timer is released.

As an embodiment, when the second message indicates that the RRC state of the first node is the RRC idle state, the first timer is released.

As one embodiment, the first node is in the RRC inactive state after sending the first message until expiration of the first timer.

Example 6

Embodiment 6 illustrates an inter-layer message interaction diagram of an RRC sublayer and a MAC sublayer according to an embodiment of the present application, as shown in fig. 6. Both the RRC sublayer and the MAC sublayer in fig. 6 belong to the first node.

As one embodiment, a first counter is maintained at a MAC sublayer, the first counter being used to count the number of the first type of data units transmitted through the MAC sublayer of the first node.

As an embodiment, any data unit of the first class of data units belongs to the first set of radio bearers; the first set of radio bearers is associated with a first set of logical channel identifiers; any radio bearer in the first set of radio bearers is indicated by one logical channel identity in the first set of logical channel identities.

As an embodiment, the phrase associating the first set of radio bearers with the first set of logical channel identifications includes: when configuring one radio bearer in the first set of radio bearers, simultaneously including an identification of the radio bearer and a logical channel identification of the radio bearer.

As an embodiment, a MAC sub-pdu includes a MAC subheader and a MAC SDU, where the MAC subheader includes a logical channel identifier, and the logical channel identifier indicates a radio bearer to which the MAC SDU belongs.

As an embodiment, in the MAC sublayer, it is identified whether a MAC sdu of a MAC sub pdu includes a bit of the first type data unit through a MAC subheader of the MAC sub pdu; when the MAC subheader of the MAC sub pdu includes any one of the logical channel identifiers in the first set of logical channel identifiers, the MAC SDU of the MAC sub pdu includes bits of the first type of data unit; when the MAC subheader of the MAC sub-pdu includes a logical channel identifier other than the first logical channel identifier set, the MAC SDU of the MAC sub-pdu does not include bits of the first type data unit.

As an embodiment, the first counter starts counting when a random access procedure including the first message is initiated.

As one embodiment, the first counter starts counting when initiating an SDT procedure that includes the first message.

As an embodiment, the first counter starts counting when the first message is sent.

As an embodiment, the first counter starts counting with the first message.

As one embodiment, the phrase accompanies the first message, the first counter starting to count includes: sending the first message and the first counter to start counting is not detachable (atomic).

As one embodiment, the phrase accompanies the first message, the first counter starting to count includes: the sending of the first message and the start of counting by the first counter are concomitant with each other.

As one embodiment, the phrase accompanies the first message, the first counter starting to count includes: sending the first message is used to trigger the first counter to start counting.

As one embodiment, the phrase accompanies the first message, and the first counter starts counting comprises: when the first message is sent (uplink transmission of the first message), the first counter starts counting.

As one embodiment, the phrase accompanies the first message, and the first counter starts counting comprises: the first counter starts counting immediately after the first message (Following the transmission of the first message) is sent.

As one embodiment, the phrase accompanies the first message, the first counter starting to count includes: the first message is sent immediately following the start of counting by the first counter.

As one embodiment, the phrase accompanies the first message, and the first counter starts counting comprises: when a random access procedure (uplink initiation of the procedure) to which the first message belongs is initiated, the first counter starts counting.

As one embodiment, the phrase accompanies the first message, the first counter starting to count includes: the first counter starts counting immediately after the random access procedure to which the first message belongs is initiated.

As one embodiment, the phrase accompanies the first message, the first counter starting to count includes: and starting counting immediately after the first counter, and initiating a random access process to which the first message belongs.

As one embodiment, the phrase accompanies the first message, and the first counter starts counting comprises: the first counter starts counting when a Small Data Transmission (SDT) process to which the first message belongs is initiated.

As one embodiment, the phrase accompanies the first message, and the first counter starts counting comprises: the first counter starts counting following initiation of a Small Data Transmission (SDT) process to which the first message belongs.

As one embodiment, the phrase accompanies the first message, and the first counter starts counting comprises: initiating a Small Data Transmission (SDT) process to which the first message belongs immediately after the first counter starts counting.

As an embodiment, the first counter stops counting when the first counter exceeds the first threshold.

As an embodiment, the first counter restarts counting when the first counter exceeds the first threshold.

As an embodiment, the first counter stops counting when the second message is received.

As an embodiment, the first counter stops counting when the first node is in the RRC idle state.

As an embodiment, the first counter stops counting when the first node is in the RRC connected state.

As one embodiment, the first counter is established (Setup) only when the first node is in the RRC inactive state.

As an embodiment, the first counter is released (Release) when the first node is in the RRC idle state or the RRC connected state.

For one embodiment, the phrase the first counter exceeding the first threshold comprises: the value of the first counter is greater than the first threshold.

As one embodiment, the phrase the first counter exceeding the first threshold comprises: the value of the first counter is equal to the first threshold.

As one embodiment, the phrase the first counter exceeding the first threshold comprises: the value of the first counter is not less than the first threshold.

As an embodiment, the first counter starts counting in response to the first timer starting or restarting.

As an embodiment, in response to the first timer starting or restarting, sending a second indication from the RRC sublayer to a lower layer, the second indication being used to indicate that the first counter starts counting; the lower layer is an MAC sublayer.

As one embodiment, the phrase the first counter starting or restarting counting includes: setting a value of the first counter to 0.

In case a of embodiment 6, in response to the number of data units of the first class transmitted after the last start of the first timer exceeding the first threshold, communicating a first indication from the MAC sublayer to the RRC sublayer of the first node; the first indication is used to trigger restarting the first timer; the first counter restarts counting.

In case B of embodiment 6, communicating a first indication from the MAC sublayer of the first node to the RRC sublayer of the first node in response to the number of data units of the first type transmitted after the most recent start of the first timer exceeding the first threshold; the first indication is used to trigger restarting the first timer; sending, from the RRC sublayer of the first node to the MAC sublayer of the first node, the second indication in response to the first timer starting or restarting, the second indication being used to trigger the first counter to restart counting.

Example 7

Embodiment 7 illustrates a processing flow diagram of a first node according to an embodiment of the present application, as shown in fig. 7. The steps of fig. 7 are performed at the first node.

In fig. 7, a first timer is started in step S701; in step S702, it is determined whether the first timer expires; if yes, go to step S703; if not, go to step S704; in step S703, transitioning from the RRC inactive state to the first RRC state; in step S704, it is determined whether a second message is received; if yes, go to step S705; if not, executing step S706; in step S705, the first timer is stopped; determining in step S706 whether the number of data units of the first type transmitted after the latest start of the first timer exceeds a first threshold; if yes, go to step S707; if not, jumping to the step S702; the first timer is restarted in step S707.

As an embodiment, when the first type of data unit is transmitted after the last start of the first timer, the first timer is in a running state.

As an embodiment, transmission of the data units of the first type in the RRC inactive state is stopped after the first timer expires.

In one embodiment, the first timer is not in the active state after transitioning from the RRC inactive state to the first RRC state.

In one embodiment, the first timer is not in the active state after transitioning from the RRC inactive state to the RRC idle state.

In one embodiment, the first timer is not in the active state after transitioning from the RRC inactive state to the RRC connected state.

Example 8

Embodiment 8 illustrates a flow chart of a first timer according to an embodiment of the present application, as shown in fig. 8. The steps of fig. 8 are performed at the first node.

The first timer is started or restarted at step S801; in step S802, the first timer is updated in the next time interval; in step S803, it is determined whether the first timer has expired, and if so, the process ends, and if not, the process jumps back to step S802.

As an embodiment, the first timer is updated every said time interval when the first timer is running.

As an embodiment, when the first timer is not in the running state, updating of the first timer at each of the time intervals is stopped.

As an example, the time interval is 1 millisecond.

As an embodiment, the time interval is one subframe (subframe).

As an embodiment, the time interval is a slot (slot) whose duration is related to a frequency domain subcarrier spacing (subgrierspacting).

As an embodiment, the time interval includes 14 multicarrier symbols (symbols).

As an embodiment, the time interval comprises 12 multicarrier symbols.

As an embodiment, the first expiration value of the first timer is configured by the network.

As an embodiment, the first expiration value of the first timer is configured by RRC signaling.

For one embodiment, the first expiration value of the first timer is configured by a SIB.

As one embodiment, the first expiration value of the first timer is configured by SIB 1.

As an embodiment, the first expired value of the first timer is carried in all or part of an IE (Information Element) in RRC signaling.

As an embodiment, the first expired value of the first timer is carried in a full or partial Field (Field) in an IE in RRC signaling.

As one embodiment, the first expiration value of the first timer is expressed in milliseconds.

As one embodiment, the first expiration value of the first timer is expressed in subframes.

As an embodiment, the first expiration value of the first timer is expressed in time slots.

As one embodiment, starting or restarting the first timer sets the value of the first timer to 0, the phrase updating the first timer comprising: adding 1 to the value of the first timer; the first timer expires when the value of the first timer is the first expiration value of the first timer.

As one embodiment, starting or restarting the first timer sets a value of the first timer to the first expiration value of the first timer, the phrase updating the first timer comprising: subtracting 1 from the value of the first timer; when the value of the first timer is 0, the first timer expires.

In one embodiment, the first timer expires before stopping the counting.

As an embodiment, the first timer is running when the first node sends or receives the data unit of the first type.

As an example, when the time interval is 1 millisecond, the next time interval is one millisecond that is upcoming.

As an embodiment, when the time interval is a subframe, the next time interval is an upcoming subframe.

As an embodiment, when the time interval is a time slot, the next time interval is an upcoming time slot.

Example 9

Embodiment 9 is a block diagram illustrating a configuration of a processing apparatus in a first node according to an embodiment of the present application, as shown in fig. 9. In fig. 9, a first node processing apparatus 900 includes a first receiver 901 and a first transmitter 902. The first receiver 901 comprises at least one of a transmitter/receiver 454 (including an antenna 452), a receive processor 456, a multiple antenna receive processor 458, or a controller/processor 459 of fig. 4 herein; the first transmitter 902 includes at least one of the transmitter/receiver 454 (including the antenna 452), the transmit processor 468, the multi-antenna transmit processor 457, or the controller/processor 459 of fig. 4 herein.

In embodiment 9, the first receiver 901 maintains the first timer; a first transmitter 902 that transmits a first message, the first message comprising RRC signaling; transitioning from an RRC inactive state to a first RRC state in response to expiration of the first timer; wherein the behavior maintenance first timer comprises: restarting the first timer in response to the number of data units of the first type transmitted after the last start of the first timer exceeding a first threshold; stopping the first timer in response to receiving a second message comprising RRC signaling, the second message used in response to the first message, if received; the first RRC state is one of a first set of candidate states, the first set of candidate states including an RRC idle state; the first threshold is configurable or is a positive integer greater than 1.

As an embodiment, the first transmitter 902, in response to the number of data units of the first type transmitted after the last start of the first timer exceeding a first threshold, passes a first indication from the MAC sublayer to an upper layer; wherein the first indication is used to trigger the action to restart the first timer, the number of data units of the first type being calculated at a MAC sub-layer.

As an embodiment, the first timer is maintained at the RRC sublayer.

As an embodiment, the first receiver 901 receives a third message; wherein the receiving time of the third message is earlier than the sending time of the first message; the third message is used to enable transmission of a first set of radio bearers in the RRC inactive state; any one of the first type data units belongs to one of the first set of radio bearers.

As an embodiment, the first receiver 901 receives a third message; wherein the receiving time of the third message is earlier than the sending time of the first message; the third message is used to enable transmission of a first set of radio bearers in the RRC inactive state; any first type data unit belongs to one radio bearer in the first radio bearer set; said first receiver 901, after receiving said third message and before sending said first message, receives a first set of data units; wherein the data volume of the first set of data units is not greater than a first threshold; any data unit in the first set of data units belongs to the first class of data units; the first node is in the RRC inactive state when sending the first message.

As one embodiment, the second message indicates an RRC state of the first node.

Example 10

Embodiment 10 illustrates a block diagram of a processing apparatus in a second node according to an embodiment of the present application, as shown in fig. 10. In fig. 10, the second node processing apparatus 1000 includes a second receiver 1001 and a second transmitter 1002. The second receiver 1001 includes at least one of the transmitter/receiver 418 (including the antenna 420), the receive processor 470, the multiple antenna receive processor 472, or the controller/processor 475 of fig. 4 herein; the second transmitter 1002 includes at least one of the transmitter/receiver 418 (including the antenna 420), the transmit processor 416, the multi-antenna transmit processor 471 or the controller/processor 475 of fig. 4 of the present application.

In embodiment 10, a second receiver 1001 receives a first message, the first message including RRC signaling; wherein the first timer is maintained; in response to expiration of the first timer, the RRC inactive state is transitioned to a first RRC state; the first timer is maintained comprising: in response to the number of data units of the first class transmitted after the last start of the first timer exceeding a first threshold, the first timer is restarted; if a second message is received, the first timer is stopped in response to receiving the second message, the second message including RRC signaling, the second message being used in response to the first message; the first RRC state is one of a first set of candidate states, the first set of candidate states including an RRC idle state; the first threshold is configurable or is a positive integer greater than 1.

As an embodiment, the first indication is passed from the MAC sublayer to the upper layer in response to the number of data units of the first type transmitted after the latest start of the first timer exceeding a first threshold; wherein the first indication is used to trigger the first timer to be restarted, the number of the first type of data units being calculated at a MAC sub-layer.

As an embodiment, the first timer is maintained at the RRC sublayer.

As an example, the second transmitter 1002, transmits the third message; wherein the sending time of the third message is earlier than the receiving time of the first message; the third message is used to enable transmission of a first set of radio bearers in the RRC inactive state; any one of the first type data units belongs to one of the first set of radio bearers.

As an example, the second transmitter 1002, transmits the third message; wherein the sending time of the third message is earlier than the receiving time of the first message; the third message is used to enable transmission of a first set of radio bearers in the RRC inactive state; any first type data unit belongs to one radio bearer in the first radio bearer set; after sending the third message and before receiving the first message, a first set of data units is received; wherein the data volume of the first set of data units is not greater than a first threshold; any data unit in the first set of data units belongs to the first class of data units; a sender of the first message is in the RRC inactive state when sending the first message.

As one embodiment, the second message indicates an RRC state of the sender of the first message.

It will be understood by those skilled in the art that all or part of the steps of the above methods may be implemented by instructing relevant hardware through a program, and the program may be stored in a computer readable storage medium, such as a read-only memory, a hard disk or an optical disk. Alternatively, all or part of the steps of the above embodiments may be implemented by using one or more integrated circuits. Accordingly, the module units in the above embodiments may be implemented in a hardware form, or may be implemented in a form of software functional modules, and the present application is not limited to any specific form of combination of software and hardware. The first Type of Communication node or UE or terminal in the present application includes, but is not limited to, a mobile phone, a tablet computer, a notebook, a network card, a low power consumption device, an eMTC (enhanced Machine Type Communication) device, an NB-IoT device, a vehicle-mounted Communication device, an aircraft, an airplane, an unmanned aerial vehicle, a remote control airplane, and other wireless Communication devices. The second type of communication node, base station or network side device in this application includes, but is not limited to, a macro cell base station, a micro cell base station, a home base station, a relay base station, an eNB, a gNB, a Transmission and Reception node TRP (Transmission and Reception Point), a relay satellite, a satellite base station, an air base station, and other wireless communication devices.

The above description is only a preferred embodiment of the present application, and is not intended to limit the scope of the present application. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A first node configured for wireless communication, comprising:

a first receiver maintaining a first timer;

2. The first node of claim 1, comprising:

the first transmitter, responsive to the number of data units of the first type transmitted after the most recent start of the first timer exceeding a first threshold, passing a first indication from the MAC sublayer to an upper layer;

wherein the first indication is used to trigger the action to restart the first timer, the number of the first type of data units being calculated at a MAC sub-layer.

3. The first node according to claim 1 or 2, wherein the first timer is maintained in the RRC sublayer.

4. The first node according to any of claims 1 to 3, comprising:

the first receiver receives a third message;

5. The first node of claim 4, comprising:

the first receiver, after receiving the third message and before sending the first message, receiving a first set of data units;

wherein the data volume of the first set of data units is not greater than a first threshold; any data unit in the first data unit set belongs to the first type of data unit; the first node is in the RRC inactive state when sending the first message.

6. The first node according to any of claims 1-5, wherein the second message indicates the RRC state of the first node.

7. A second node configured for wireless communication, comprising:

8. Second node according to claim 7, characterized in that in response to the number of data units of the first type transmitted after the last start of the first timer exceeding a first threshold value a first indication is passed from the MAC sublayer to the upper layer;

9. A method in a first node used for wireless communication, comprising:

maintaining the first timer;

wherein the behavior maintenance first timer comprises: restarting said first timer in response to the number of data units of the first type transmitted after the most recent start of said first timer exceeding a first threshold; stopping the first timer in response to receiving a second message comprising RRC signaling, the second message used in response to the first message, if received; the first RRC state is one of a first set of candidate states, the first set of candidate states including an RRC idle state; the first threshold is configurable or is a positive integer greater than 1.

10. A method in a second node used for wireless communication, comprising:

receiving a first message, the first message comprising RRC signaling;