WO2023168625A1

WO2023168625A1 - Improving data transmission in telecommunication systems

Info

Publication number: WO2023168625A1
Application number: PCT/CN2022/079913
Authority: WO
Inventors: Yonggang Wang; Hua Chao; Zexian Li; Guillermo POCOVI
Original assignee: Nokia Shanghai Bell Co., Ltd.; Nokia Solutions And Networks Oy; Nokia Technologies Oy
Priority date: 2022-03-09
Filing date: 2022-03-09
Publication date: 2023-09-14

Abstract

Embodiments of the present disclosure relate to devices, methods, apparatuses and computer-readable storage medium for improvement of data transmission in telecommunication system. In some example embodiments, a terminal device initiates a dual connectivity and/or multi-connectivity to a data network via a first network device and a second network device, respectively. The terminal device correlated a first data unit having a first identifier for the first network device with a second data unit having a second identifier for the second network device, the first identifier and the second identifier being used in a first radio link protocol layer. Then, the terminal device transmits the data unit having the correlated first identifier to the first network and transmit the data unit having the correlated second identifier to the second network device.

Description

IMPROVING DATA TRANSMISSION IN TELECOMMUNICATION SYSTEMS

TECHNICAL FIELD

Embodiments of the present disclosure generally relate to the field of telecommunication, and in particular, to a device, method, apparatus and computer-readable storage medium for improving data transmission in telecommunication system.

BACKGROUND

With the development of communication technology, redundant transmission has been introduced to enhance the reliability of communication, for example, a dual/multi-connectivity has been introduced. In a dual/multi-connectivity, a terminal device may connect to a data network via two or more paths which being relatively independent from each other, in order to ensure the successful data transmission. In some situations, data transmission in one path of the dual/multi-connectivity may also experience transmission failures. In order to improve overall reliability of the dual/multi-connectivity, it is beneficial to improve the transmission reliability of each path in the dual/multi-connectivity. Further, the reduction of latency of data transmission in the dual/multi-connectivity is also a key aspect.

SUMMARY

In general, example embodiments of the present disclosure provide a device, method, apparatus and computer-readable storage medium for improvement of data transmission in telecommunication system.

In a first aspect, there is provided a terminal device. The terminal device comprises at least one processor and at least one memory storing computer program code. The at least one memory and the computer program code configured to, with the at least one processor, cause the terminal device to initiate a dual connectivity and/or multi-connectivity to a data network via a first network device and a second network device, respectively. The terminal device is further caused to correlate a first data unit having a first identifier for the first network device with a second data unit having a second identifier for the second network device, the first identifier and the second identifier being used in a first radio link protocol layer; and transmit the data unit having the correlated first identifier to the first network and transmit the data unit having the correlated second identifier to the second network device.

In a second aspect, there is provided a first network device. The first network device comprises at least one processor and at least one memory storing computer program code. The at least one memory and the computer program code configured to, with the at least one processor, cause the first network device to receive a first data unit having a first identifier from a terminal device, the first data unit being correlated by the terminal device with a second data unit having a second identifier for a second network device, the first identifier and the second identifier being used in a first radio link protocol layer. The first network device and second network device are used, respectively, for a dual connectivity and/or multi-connectivity from the terminal device to a data network.

In a third aspect, there is provided a second network device. The second network device comprises at least one processor and at least one memory storing computer program code. The at least one memory and the computer program code configured to, with the at least one processor, cause the second network device to receive a second data unit having a second identifier from a terminal device, the second data unit being correlated by the terminal device with a first data unit having a first identifier for a first network device, the first identifier and second identifier being used in a first radio link protocol layer. The first network device and second network device being used, respectively, for a dual connectivity and/or multi-connectivity from the terminal device to a data network.

In a fourth aspect, there is provided a method implemented in a terminal device. In the method, the terminal device initiates a dual connectivity and/or multi-connectivity to a data network via a first network device and a second network device, respectively. The terminal device correlates a first data unit having a first identifier for the first network device with a second data unit having a second identifier for the second network device, the first identifier and the second identifier being used in a first radio link protocol layer. Then, the terminal device transmits the data unit with the correlated first identifier to the first network and transmits the data unit with the correlated second identifier to the second network device.

In a fifth aspect, there is provided a method implemented in a first network device. In the method, the first network device receives a first data unit having a first identifier, the first data unit being correlated by the terminal device with a second data unit having a second identifier for a second network device from a terminal device, the first identifier and the second identifier being used in a first radio link protocol layer. The first network device and second network device are used, respectively, for a dual connectivity and/or multi-connectivity from the terminal device to a data network.

In a sixth aspect, there is provided a method implemented in a second network device. In the method, the second network device receives a second data unit having a second identifier from a terminal device, the second data unit being correlated by the terminal device with a first data unit having a first identifier for a first network device, the first identifier and second identifier being used in a first radio link protocol layer. The first network device and second network device being used, respectively, for a dual connectivity and/or multi-connectivity from the terminal device to a data network.

In a seventh aspect, there is provided an apparatus comprising means for performing the method according to any of the fourth to sixth aspects.

In a tenth aspect, there is provided computer-readable storage medium having instructions stored thereon. The instructions, when executed on at least one processor, cause the least one processor to perform the method according to any of the fourth to sixth aspects.

Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Through the more detailed description of some example embodiments of the present disclosure in the accompanying drawings, the above and other objects, features and advantages of the present disclosure will become more apparent, wherein:

FIG. 1 illustrates an example environment in which example embodiments of the present disclosure can be implemented;

FIG. 2 illustrates a schematic diagram of a dual connectivity in accordance with some embodiments of the present disclosure;

FIG. 3 illustrates a process for improving data transmission in telecommunication system in accordance with some embodiments of the present disclosure;

FIG. 4 illustrates a schematic diagram of synchronization for a first identifier of a first data unit and a second identifier of a second data unit in accordance with some embodiments of the present disclosure;

FIG. 5 illustrates a flowchart of an example process implemented at a terminal device in accordance with some embodiments of the present disclosure; and

FIG. 6 illustrates a flowchart of an example process implemented at a first network device in accordance with some embodiments of the present disclosure; and

FIG. 7 illustrates a flowchart of an example process implemented at a second network device in accordance with some embodiments of the present disclosure

Fig. 8 is a simplified block diagram of a device that is suitable for implementing embodiments of the present disclosure.

Throughout the drawings, the same or similar reference numerals represent the same or similar element.

DETAILED DESCRIPTION

Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitations as to the scope of the disclosure. The disclosure described herein can be implemented in various manners other than the ones described below.

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

As used herein, the terms “network device” refers to a device which is capable of providing or hosting a cell or coverage where a further device, for example a terminal device, can communicate with. Examples of a network device include, but not limited to, a Node B (NodeB or NB) , an Evolved NodeB (eNodeB or eNB) , a next generation eNB (ng-eNB) , a ng-eNB-Central Unit (ng-eNB-CU) , a ng-eNB-Distributed Unit (ng-eNB-DU) , a next generation NodeB (gNB) , a gNB-Central Unit (gNB-CU) , a gNB-Distributed Unit (gNB-DU) , a Remote Radio Unit (RRU) , a radio head (RH) , a remote radio head (RRH) , an Integrated Access and Backhaul (IAB) node, a low power node such as a femto node or a pico node, and the like.

As used herein, the term “terminal device” refers to any device having wireless or wired communication capabilities. Examples of the terminal device include, but not limited to, user equipment (UE) , personal computers, desktops, mobile phones, cellular phones, smart phones, personal digital assistants (PDAs) , portable computers, tablets, wearable devices, internet of things (IoT) devices, Internet of Everything (IoE) devices, machine type communication (MTC) devices, device on vehicle for V2X communication where X means pedestrian, vehicle, or infrastructure/network, devices for Integrated Access and Backhaul (IAB) , or image capture devices such as digital cameras, gaming devices, music storage and playback appliances, or Internet appliances enabling wireless or wired Internet access and browsing and the like. Herein, the term “terminal device” can be used interchangeably with a UE.

The term “circuitry” used herein may refer to hardware circuits and/or combinations of hardware circuits and software. For example, the circuitry may be a combination of analog and/or digital hardware circuits with software/firmware. As a further example, the circuitry may be any portions of hardware processors with software including digital signal processor (s) , software, and memory (ies) that work together to cause an apparatus, such as a terminal device or a network device, to perform various functions. In a still further example, the circuitry may be hardware circuits and or processors, such as a microprocessor or a portion of a microprocessor, that requires software/firmware for operation, but the software may not be present when it is not needed for operation. As used herein, the term circuitry also covers an implementation of merely a hardware circuit or processor (s) or a portion of a hardware circuit or processor (s) and its (or their) accompanying software and/or firmware.

As used herein, the singular forms “a” , “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. The term ‘includes’ and its variants are to be read as open terms that mean “includes, but is not limited to. The term “based on” is to be read as “at least in part based on” . The term “one embodiment” and ‘an embodiment” are to be read as ‘at least one embodiment” . The term “another embodiment” is to be read as “at least one other embodiment” . The terms “first” , “second” , and the like may refer to different or same objects.

As mentioned above, the redundant transmission, such as the dual/multi-connectivity, has been introduced to improve the transmission reliability of a data network. However, a transmission failure may also occur in one path of the dual/multi-connectivity, and the retransmission of a failed data unit may further cause a latency/delay in the transmission.

Example embodiments of the present disclosure provide a scheme for improving data transmission in the dual/multi-connectivity in a communication. In this scheme, a first network device in one path of the dual/multi-connectivity may communicate data units with a second network device in another path of the dual/multi-connectivity, such that a “ladder redundancy” architecture can be formed between different paths of the dual/multi-connectivity. Specifically, a terminal device initiates a dual/multi-connectivity via the first network device and second network device to the data network. Then, the terminal device correlates a data unit in a first data stream for a first path of the dual/multi-connectivity with a corresponding data unit in a second data stream for a second path of the dual/multi-connectivity, for example, by utilizing an identifier for the data unit. The terminal device transmits the correlated first data stream into one path and transmits the correlated second data stream into another path. Once the first (or second) network device detects a reception failure of a data unit in the data stream, based on correlated identifier in the data unit, the first/second network device may transmit a retransmission request for the data unit to the terminal device and a forwarding request to the second (or first) network device simultaneously. In this way, the first (or second) network device may request the forwarding of a specific data unit from the second (or first) network device based on the correlation between two data streams. Further, the network device may autonomously configure trigger conditions for request the forwarding, for example, a non-continuity reception of data units in one data stream.

In this way, the reliability of data transmission in the dual/multi-connectivity may be further improved, and the latency or delay of data retransmission can be adjusted on demand.

For discussion clarity, the embodiments described as below are based on dual-connectivity architecture. However, it should be understood that any embodiments described in the disclosure may be implemented in a multi-connectivity architecture in which the terminal device connects to the data network via multiple paths (more than two paths) .

FIG. 1 illustrates an example environment 100 in which example embodiments of the present disclosure can be implemented.

The environment 100, which may be a part of a communication network, comprises a data network 101, a terminal device 110, a first network device 120 and a second network device 130. The terminal device 110 may initiate a dual/multi-connectivity to a data network 140 via the first network device 120 and second network device 130, respectively.

It is to be understood that the number of the terminal devices and the network device is shown in the environment 100 only for the purpose of illustration, without suggesting any limitation to the scope of the present disclosure. In some example embodiments, the environment 100 may comprise a further terminal device and/or a further network device.

It is to be understood that the

network device

120 or 130 may also refer to or comprise any network entity, for example, a Radio Link Control (RLC) entity, a Packet Data Convergence Protocol (PDCP) entity, and any other network functionality entities known or in the future.

The terminal device 110 can communicate with the network devices or with a further terminal device (not shown) directly or via the network devices. The first network device 120 can communicate with the second network device 130 by wired (for example, optical fiber communication) or wireless communication technologies. The communications in the environment 100 may follow any suitable communication standards or protocols, which are already in existence or to be developed in the future, such as Universal Mobile Telecommunications System (UMTS) , long term evolution (LTE) , LTE-Advanced (LTE-A) , the fifth generation (5G) New Radio (NR) , Wireless Fidelity (Wi-Fi) and Worldwide Interoperability for Microwave Access (WiMAX) standards, and employs any suitable communication technologies, including, for example, Multiple-Input Multiple-Output (MIMO) , Orthogonal Frequency Division Multiplexing (OFDM) , time division multiplexing (TDM) , frequency division multiplexing (FDM) , code division multiplexing (CDM) , Bluetooth, ZigBee, and machine type communication (MTC) , enhanced mobile broadband (eMBB) , massive machine type communication (mMTC) , ultra-reliable low latency communication (URLLC) , Carrier Aggregation (CA) , Dual Connection (DC) , and New Radio Unlicensed (NR-U) technologies.

FIG. 2 illustrates a schematic diagram 200 of a dual connectivity in accordance with some embodiments of the present disclosure. For purpose of discussion, the schematic diagram 200 will be described with reference to FIG. 1.

In the schematic diagram 200, in an example of dual-connectivity architecture, the ladder redundancy architecture in a dual connectivity is shown. In this ladder redundancy architecture, the network devices in different paths, for example, the first network device 120 and the second network device 130, may forward data units received from the terminal device 110 with each other, for example, RLC data units. In one example embodiment, upon detecting a reception failure of a RLC data unit, the first network device 120 may transmit a request for the forwarding of this RLC data unit to the second network device 130. Then, the second network device 130 may forward this RLC data unit to the first network device 120, upon receiving the request. In addition or alternatively, in some example embodiments, the first network device 120 and second network device 130 may forward all the RLC data units received from the terminal device 110 to each other. In these embodiments, the

network devices

120 and 130 may eliminate the duplicated RLC data units based on pre-correlation information between the different data streams in corresponding paths of the dual/multi-connectivity. For example, the pre-correlation information may comprise the correlated identifier for data units in different data streams.

As such, the reliability of data transmission can be further improved. For example, in a regular dual/multi-connectivity, the end-to-end outage probability is exponentially increase with respect to the number of nodes N in a path. In the above architecture, the end-to-end outage probability is linear increase with respect to the number of nodes N in a path.

FIG. 3 illustrates a process 300 for improvement of data transmission in telecommunication system in accordance with some embodiments of the present disclosure. For purpose of discussion, the flowchart 200 will be described with reference to FIG. 1.

In the process 300, at step 310, the terminal device 110 initiates a dual connectivity and/or multi-connectivity to a communication 101 via a first network device 120 and a second network device 130, respectively.

At step 320, upon the dual connectivity and/or multi-connectivity has been initiated the terminal device 110 correlates a first data unit having a first identifier for the first network device 120 with a second data unit having a second identifier for the second network device 130. The first identifier and the second identifier are used in a first radio link protocol layer. In some example embodiments the first radio link protocol layer may be the RLC layer. In some other embodiments, the first radio protocol layer may be any other data transmission layers, for example, a Medium Access Control layer. It is to be understood that there is not any limitation regarding the protocol layer. In some example embodiments, the identifier of the data unit may be a sequence number or any other identifier for identifying the data unit uniquely in a corresponding process phase.

By the correlation step 320, the terminal device 110 may pre-correlate a first data stream for a first path comprising the first network device 120 with a second data stream for a second path comprising the second network device 130. As such, the first network device 120 may have the knowledge of a certain data unit in the second data stream corresponding to a data unit in the first data stream, such that the first network device 120 and second network device 130 may forward a certain data unit with each other on demand. In some example embodiments, the first data unit and the second data unit comprise (or carry) same data information to be transmitted from the terminal device 110.

In some example embodiments, the correlation between the first data unit and the second data unit may be performed by the terminal device 110, based on a third identifier of the first data unit in a second radio link protocol layer and a fourth identifier of the second data unit in the second radio link protocol layer. For example, the terminal device 110 may synchronize the first identifier of the first data unit and the second identifier of the second data unit based on the third identifier and fourth identifier. To discuss the correlation step 320 more clearly, refer to FIG. 4.

FIG. 4 illustrates a schematic diagram 400 of synchronization for the first identifier of the first data unit and the second identifier of the second data unit in accordance with some embodiments of the present disclosure.

In an example, during the procedure of data transmission, the encapsulation operation may be performed on a data unit correspondingly in different radio link protocol layers. With the encapsulation, the data unit is added a unique identifier for the radio link protocol layer, for example, a sequence number. In an example, in the RLC layer, the data units from a higher layer, for example, the PDCP layer, are numbered integer SN cycling, and the sequence number (such as, RLC identifier for the data unit) is incremented by one for every RLC layer data unit. However, the RLC identifier (RLC sequence number) always counts from 0 upon the RLC session has been established. In this situation, if different paths in the dual connectivity/multi-connectivity are initiated at different time instances, the first network device 120 or second network device 130 cannot determine the corresponding data unit in a counterpart data stream based on the conventionally numbered RLC identifiers. For this situation, the terminal device may synchronize RLC identifiers for data units in RLC layer based on identifiers for these data units in a higher radio link protocol layer. For example, the first data unit in the first data stream and the second data unit in the second data stream which carry the same data information to be transmitted may have the same PDCP sequence in PDCP layer. In some example embodiments, since the PDCP sequence numbers for the data units carrying same data information are identical, the terminal device 110 may synchronize the first identifier of the first data unit and the second identifier of the second data unit, based on the third identifier for the first data unit and the fourth identifier for the second data unit, the third identifier and fourth identifier are used in the PDCP layer. In this way, in the first radio link protocol layer, the first identifier for the first data unit and the second identifier for the second data unit may be synchronized based on the identifiers used in a higher radio link protocol, for example a second radio link protocol. In addition or alternatively, the first identifier and second identifier may be synchronized based other identifiers for the data units in other radio link protocol layers.

With the synchronization between the first identifier and the second identifier, the first data stream and the second data stream for different paths may be correlated by the terminal device 110. In turn, the

network device

120 and 130 may have the knowledge of data units in counterpart data stream based on the correlated/synchronized identifiers, such that the

network device

120 or 130 may request a certain data unit from the other network device on demand.

Referring back to FIG. 3, in addition or alternatively to the synchronization between the first identifier and second identifier, at step 320, the terminal device 110 may correlate the first data unit by determining a difference between the first identifier and the second identifier. For example, the terminal device 110 may determine the gap/spacing between the first RLC sequence of the first data unit and the second RLC sequence of the second data unit. Then, the terminal device 110 may transmit a message indicating the determined difference to the first network device 120 and second network device 130. In this way, the

network device

120 and 130 may also have the knowledge of data units in counterpart data stream based on the difference information between first data stream and second data stream, such that the

network device

At step 330, after the correlation between the first data unit and second data unit, the terminal device 110 transmits the first data unit with the correlated first identifier to the first network device 120 and transmits the second data unit with the correlated second identifier to the second network device 130. In some example embodiments, the terminal device 110 may transmit the first data unit to the first network device 120 and the second data unit to the second network device 130 in uplink transmission via a radio link interface.

In some example embodiments, at step 340, the first network device 120 and the second network device 130 may forward all the received data units from the terminal device 110 to each other, in order to improve the reliability. In this case, the first network device 120 and second network device 130 may determine and eliminate the duplicated data units based on the correlated first and correlated second identifiers. In some example embodiments, the first network device 120 may determine whether the received second data unit comprises the same data information as the first data unit. Further, if the received second data unit comprises the same data information as the first data unit, the first network device 120 may select any of the first data unit and the received second data unit for transmitting to the data network and remove the other data unit.

For communication efficiency or saving the communication resources, in addition or alternatively, the first network device 120 and second network device 130 may not have to forward all the received data units.

In some example embodiments, at step 350, the first network device 120 (or the second network device 130) may detect a reception failure of the first data unit which may be caused by a deterioration of radio conditions, or other reasons. In some example embodiments, the first network device 120 may detect the reception failure based on the RLC entity comprised in the first network device 120 issues NACK of the ARQ feedback. In this case, at step 360, based on the correlated first identifier, the first network device 120 may also transmit a retransmission request for the data unit which being received failed to the second network device 130. At step 370, the second network device 130 may then transmit (370) the data unit to the first network device 120 upon receiving the request. Since the network devices may be connected directly via a fiber link, the latency of forwarding by the second network device 130 is significantly smaller than the retransmission from the terminal device 110.

In addition or alternatively to waiting for the ARQ trigger, the first network device 120 may request for a data unit from the second network device 130 in advance. In some example embodiments, at step 350, if the first device 120 detects that a non-continuity for identifiers of received data units, for example, a non-continuity for RLC sequence numbers of data units, the first device 120 may transmit, at step 360, a request for the missing data unit to the second network device based on the correlated first identifier. Then, the second network device 130 may transmit the missing data unit to the first network device 120 upon receiving the request. In this way, the network device may determine a “reception failure” of a data unit earlier than waiting for the ARQ trigger, and the latency/delay of the data retransmission may be further decreased.

FIG. 5 illustrates a flowchart of an example method 500 implemented at a terminal device in accordance with some embodiments of the present disclosure.

The method 500 can be implemented at the terminal device 110 shown in FIG. 1. For the purpose of discussion, the method 500 will be described with reference to FIG. 1. It is to be understood that the method 500 may include additional acts not shown and/or may omit some shown acts, and the scope of the present disclosure is not limited in this regard.

At 510, the terminal device 110 initiates a dual connectivity and/or multi-connectivity to a data network via a first network device 120 and a second network device 130, respectively.

At 520, the terminal device 110 correlates a first data unit having a first identifier for the first network device 120 with a second data unit having a second identifier for the second network device 130, the first identifier and the second identifier being used in a first radio link protocol layer.

At 530, the terminal device 110 transmits the data unit having the correlated first identifier to the first network 120 and transmits the data unit having the correlated second identifier to the second network device 130.

In some example embodiments, the first data unit and the second data unit comprise same data information to be transmitted.

In some example embodiments, the terminal device 110 synchronizes the first identifier and the second identifier based on a third identifier of the first data unit in a second radio link protocol layer and a fourth identifier of the second data unit in the second radio link protocol layer, the second radio link protocol layer being a higher protocol layer than the first radio link protocol layer.

In some example embodiments, the terminal device 110 determines a difference between the first identifier and the second identifier, and transmits a message indicating the difference to the first network device and second network device.

FIG. 6 illustrates a flowchart of an example method 600 implemented at a first network device in accordance with some embodiments of the present disclosure.

The method 600 can be implemented at the first network device 120 shown in FIG. 1. For the purpose of discussion, the method 600 will be described with reference to FIG. 1. It is to be understood that the method 600 may include additional acts not shown and/or may omit some shown acts, and the scope of the present disclosure is not limited in this regard.

At 610, the first network device 120 receives, from a terminal device 110, a first data unit having a first identifier, the first data unit being correlated by the terminal device 110 with a second data unit having a second identifier for a second network device 130, the first identifier and the second identifier being used in a first radio link protocol layer. The first network device and second network device are used, respectively, for a dual connectivity and/or multi-connectivity from the terminal device 110 to a data network.

In some example embodiments, the correlation of the first identifier and second identifier is based on a third identifier of the first data unit in a second radio link protocol and a fourth identifier of the second data unit in the second radio link protocol layer, the second radio link protocol layer being a higher protocol layer than the first radio link protocol layer.

In some example embodiments, the first network device 120 receives, from the terminal device 110, a message indicating a difference between the first identifier and second identifier.

In some example embodiments, the first network device 120 in response to detecting a non-continuity for identifiers of received data units, determines an identifier for a missing data unit. The first network device 120 transmits, based on the determined identifier, a request for the missing data unit to the second network device and receives the missing data unit from the second network device 130.

In some example embodiments, the first network device 120 in response to detecting a reception failure of the first data unit, transmits a request for the second data unit to the second network device based on the first identifier of the first data. The first network device 120 receives the second data unit transmitted by the second network device 130 in response to the request.

In some example embodiments, the first network device 120 transmits, to the second network device 130, the first data unit and receives the second data unit from the second network device 130.

In some example embodiments, the first network device 120 determines whether the received second data unit comprises the same data information as the first data unit; and in accordance with a determination that the received second data unit comprises the same data information as the first data unit, the first network device 120 selects any of the first data unit and the received second data unit for transmitting to the data network and remove the other data unit.

FIG. 7 illustrates a flowchart of an example method 700 implemented at a second network device in accordance with some embodiments of the present disclosure.

The method 700 can be implemented at the second network device 130 shown in FIG. 1. For the purpose of discussion, the method 700 will be described with reference to FIG. 1. It is to be understood that the method 700 may include additional acts not shown and/or may omit some shown acts, and the scope of the present disclosure is not limited in this regard.

At 710, the second network device 130 receives, from a terminal device 110, a second data unit having a second identifier, the second data unit being correlated by the terminal device with a first data unit having a first identifier for a first network device 120, the first identifier and second identifier being used in a first radio link protocol layer. The first network device 120 and second network device 130 are used, respectively, for a dual connectivity and/or multi-connectivity from the terminal device to a data network.

In some example embodiments, the correlation of the first identifier and the second identifier is based on a third identifier of the data unit in a second radio link protocol layer, the second radio link protocol layer being a higher protocol layer than the first radio link protocol layer.

In some example embodiments, the correlation of the first identifier and the second identifier is based on a third identifier of the first data unit in a second radio link protocol layer and a fourth identifier of the second data unit in the second radio link protocol layer.

In some example embodiments, the second network device 130 receives, from the terminal device 110, a message indicating a difference between the first identifier and second identifier.

In some example embodiments, the second network device 130 in response to receiving a request for the second data unit from the first network device 120, transmits the second data unit to the first network device 120, the request being based on the first identifier of the first data unit for the first network device.

In some example embodiments, the second network device 130 transmits to the first network device 120 the second data unit; and receives, from the first network device 120, the first data unit.

In some example embodiments, the second network device 130 determines whether the received second data unit comprises the same data information as the first data unit; and in accordance with a determination that the received second data unit comprises the same data information as the first data unit, the second network device 130 selects any of the first data unit and the received second data unit for transmitting to the data network and remove the other data unit.

In some example embodiments, the second network device 130 receives, in uplink transmission via a radio link interface, the data unit from the terminal device 110.

FIG. 8 is a simplified block diagram of a device 800 that is suitable for implementing example embodiments of the present disclosure. The device 800 can be implemented at the terminal device 110, the first network device 120 or the second network device 130 as shown in FIG. 1.

As shown, the device 800 includes a processor 810, a memory 820 coupled to the processor 810, a communication module 830 coupled to the processor 810, and a communication interface (not shown) coupled to the communication module 830. The memory 820 stores at least a program 840. The communication module 830 is for bidirectional communications, for example, via multiple antennas or via a cable. The communication interface may represent any interface that is necessary for communication.

The program 840 is assumed to include program instructions that, when executed by the associated processor 810, enable the device 800 to operate in accordance with the example embodiments of the present disclosure, as discussed herein with reference to FIGS. 1 to 7. The example embodiments herein may be implemented by computer software executable by the processor 810 of the device 800, or by hardware, or by a combination of software and hardware. The processor 810 may be configured to implement various example embodiments of the present disclosure.

The memory 820 may be of any type suitable to the local technical network and may be implemented using any suitable data storage technology, such as a non-transitory computer readable storage medium, semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory, as non-limiting examples. While only one memory 820 is shown in the device 800, there may be several physically distinct memory modules in the device 800. The processor 810 may be of any type suitable to the local technical network, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 800 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

When the device 800 acts as the terminal device 110, the processor 810 may implement the operations or acts of the first device 110 as described above with reference to FIGS. 1 and 7. For the purpose of simplification, the details will be omitted.

When the device 800 acts as the first network device 120, the processor 810 may implement the operations or acts of the first network device 120 as described above with reference to FIGs. 1 and 7. For the purpose of simplification, the details will be omitted.

When the device 800 acts as the second network device 130, the processor 810 may implement the operations or acts of the second network device 130 as described above with reference to FIGS. 1 and 7. For the purpose of simplification, the details will be omitted.

Generally, various example embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of example embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representations, it is to be understood that the block, apparatus, system, technique or method described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor, to carry out the operations and acts as described above with reference to FIGS. 1 to 7. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various example embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the processor or controller, cause the functions or operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

In the context of the present disclosure, the computer program codes or related data may be carried by any suitable carrier to enable the device, apparatus or processor to perform various processes and operations as described above. Examples of the carrier include a signal, computer readable media.

The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A computer readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the computer readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM) , a read-only memory (ROM) , an erasable programmable read-only memory (EPROM or Flash memory) , an optical fiber, a portable compact disc read-only memory (CD-ROM) , Digital Versatile Disc (DVD) , an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular example embodiments. Certain features that are described in the context of separate example embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple example embodiments separately or in any suitable sub-combination.

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

Various example embodiments of the techniques have been described. In addition to or as an alternative to the above, the following examples are described. The features described in any of the following examples may be utilized with any of the other examples described herein.

In some aspects, a terminal device comprises at least one processor; and at least one memory including computer program code; and the at least one memory and the computer program code configured to, with the at least one processor, cause the terminal device to perform the steps according to the method 500.

In some aspects, a first network device comprises at least one processor; and at least one memory including computer program code; and the at least one memory and the computer program code configured to, with the at least one processor, cause the first network device to perform the steps according to the method 600.

In some aspects, a second network device comprises at least one processor; and at least one memory including computer program code; and the at least one memory and the computer program code configured to, with the at least one processor, cause the second network device to perform the steps according to the method 700.

In some aspects, an apparatus implemented in a terminal device comprises means for performing the steps according to the method 500.

In some aspects, an apparatus implemented in a first network device comprises means for performing the steps according to the method 600.

In some aspects, an apparatus implemented in a second network device comprises means for performing the steps according to the method 700.

In some aspects, a computer-readable storage medium having instructions, when executed on at least one processor, cause the least one processor to perform the steps of the preceding aspects.

Claims

A terminal device, comprising:

at least one processor; and

at least one memory storing computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the terminal device to:

initiate, via a first network device and a second network device, respectively, a dual connectivity and/or multi-connectivity to a data network;

correlate a first data unit having a first identifier for the first network device with a second data unit having a second identifier for the second network device, the first identifier and the second identifier being used in a first radio link protocol layer; and

transmit the first data unit having the correlated first identifier to the first network and transmit the second data unit having the correlated second identifier to the second network device.
The terminal device of claim 1, wherein the first data unit and the second data unit comprise same data information to be transmitted.
The terminal device of claim 2, wherein the terminal device is caused to correlate the first identifier and the second identifier by:

based on a third identifier of the first data unit in a second radio link protocol layer and a fourth identifier of the second data unit in the second radio link protocol layer, synchronizing the first identifier and the second identifier, the second radio link protocol layer being a higher protocol layer than the first radio link protocol layer.
The terminal device of claim 2, wherein the terminal device is caused to correlate the first identifier and the second identifier by:

determining a difference between the first identifier and the second identifier; and

transmitting, to the first network device and second network device, a message indicating the difference.
A first network device, comprising:

at least one processor; and

at least one memory storing computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the first network device to:

receive, from a terminal device, a first data unit having a first identifier, the first data unit being correlated by the terminal device with a second data unit having a second identifier for a second network device, the first identifier and the second identifier being used in a first radio link protocol layer; and

wherein the first network device and second network device are used, respectively, for a dual connectivity and/or multi-connectivity from the terminal device to a data network.
The first network device of claim 5, wherein the first data unit and the second data unit comprise same data information.
The first network device of claim 5, wherein the correlation of the first identifier and second identifier is based on a third identifier of the first data unit in a second radio link protocol and a fourth identifier of the second data unit in the second radio link protocol layer, the second radio link protocol layer being a higher protocol layer than the first radio link protocol layer.
The first network device of claim 5, wherein the first network device is further caused to:

receive, from the terminal device, a message indicating a difference between the first identifier and second identifier.
The first network device of claim 5, wherein the first network device is further caused to:

in response to detecting a non-continuity for identifiers of received data units, determine an identifier for a missing data unit;

transmit, based on the determined identifier, a request for the missing data unit to the second network device; and

receive the missing data unit from the second network device.
The first network device of claim 5, wherein the first network device is further caused to:

in response to detecting a reception failure of the first data unit, transmit, based on the first identifier of the first data unit, a request for the second data unit to the second network device; and

receive the second data unit transmitted by the second network device in response to the request.
The first network device of claim 5, wherein the first network device is further caused to:

transmit, to the second network device, the first data unit; and

receive, from the second network device, the second data unit.
The first network device of claim 11, the first network device is further caused to:

determine whether the received second data unit comprises the same data information as the first data unit; and

in accordance with a determination that the received second data unit comprises the same data information as the first data unit, select any of the first data unit and the received second data unit for transmitting to the data network and remove the other data unit.
A second network device, comprising:

at least one processor; and

at least one memory storing computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the second network device to:

receive, from a terminal device, a second data unit having a second identifier, the second data unit being correlated by the terminal device with a first data unit having a first identifier for a first network device, the first identifier and second identifier being used in a first radio link protocol layer; and

wherein the first network device and second network device being used, respectively, for a dual connectivity and/or multi-connectivity from the terminal device to a data network.
The second network device of claim 13, wherein the first data unit and the second data unit comprise same data information to be transmitted.
The second network device of claim 13, wherein the correlation of the first identifier and second identifier is based on a third identifier of the first data unit in a second radio link protocol layer and a fourth identifier of the second data unit in the second radio link protocol layer, the second radio link protocol layer being a higher protocol layer than the first radio link protocol layer.
The second network device of claim 13, wherein the second network device is further caused to:

receive, from the terminal device, a message indicating a difference between the first identifier and second identifier.
The second network device of claim 13, wherein the second device is further caused to:

in response to receiving a request for the second data unit from the first network device, transmit the second data unit to the first network device, the request being based on the first identifier of the first data unit for the first network device.
The second network device of claim 13, wherein the second device is further caused to:

transmit, to the first network device, the second data unit; and

receive, from the first network device, the first data unit.
The second network device of claim 18, the second network device is further caused to:

determine whether the received first data unit comprises the same data information as the second data unit; and

in accordance with a determination that the received first data unit comprises the same data information as the second data unit, select any of the received first data unit and the second data unit for transmitting to the data network and remove the other data unit.
A method implemented in a terminal device, comprising:

initiating, via a first network device and a second network device, respectively, a dual connectivity and/or multi-connectivity to a data network;

correlating a first data unit having a first identifier for the first network device with a second data unit having a second identifier for the second network device, the first identifier and the second identifier being used in a first radio link protocol layer; and

transmitting the first data unit with the correlated first identifier to the first network and transmit the second data unit with the correlated second identifier to the second network device.
The method of claim 20, wherein the first data unit and second data unit comprise same data information to be transmitted.
The method of claim 20, wherein correlating the first identifier and the second identifier comprises:

based on a third identifier of the first data unit in a second radio link protocol layer and a fourth identifier of the second data unit in the second radio link protocol layer, synchronizing the first identifier and the second identifier, the second radio link protocol layer being a higher protocol layer than the first radio link protocol layer.
The method of claim 20, wherein correlating the first identifier and the second identifier comprises:

determining a difference between the first identifier and the second identifier; and

transmitting, to the first network device and second network device, a message indicating the difference.
A method implemented in a first network device, comprising:

receiving, from a terminal device, a first data unit having a first identifier, the first data unit being correlated by the terminal device with a second data unit having a second identifier for a second network device, the first identifier and the second identifier being used in a first radio link protocol layer; and

wherein the first network device and second network device are used, respectively, for a dual connectivity and/or multi-connectivity from the terminal device to a data network.
The method of claim 24, wherein the first data unit and the second data unit comprise same data information to be transmitted.
The method of claim 24, wherein the correlation of the first identifier and second identifier is based on a third identifier of the first data unit in a second radio link protocol and a fourth identifier of the second data unit in the second radio link protocol layer, the second radio link protocol layer being a higher protocol layer than the first radio link protocol layer.
The method of claim 24, further comprising:

receiving, from the terminal device, a message indicating a difference between the first identifier and second identifier.
The method of claim 24, further comprising:

in response to detecting a non-continuity for identifiers of received data units, determine an identifier for a missing data unit;

transmitting, based on the determined identifier, a request for the missing data unit to the second network device; and

receiving the missing data unit from the second network device.
The method of claim 24, further comprising:

in response to detecting a reception failure of the first data unit, transmit, based on the first identifier of the first data unit, a request for the second data unit to the second network device; and

receive the second data unit transmitted by the second network device in response to the request.
The method of claim 24, further comprising:

transmit, to the second network device, the first data unit; and

receive, from the second network device, the second data unit.
The method of claim 30, further comprising:

determine whether the received second data unit comprises the same data information as the first data unit; and

in accordance with a determination that the received second data unit comprises the same data information as the first data unit, select any of the first data unit and the received second data unit for transmitting to the data network and remove the other data unit.
A method implemented in a second network device, comprising:

receiving, from a terminal device, a second data unit having a second identifier, the second data unit being correlated by the terminal device with a first data unit having a first identifier for a first network device, the first identifier and second identifier being used in a first radio link protocol layer; and

wherein the first network device and second network device being used, respectively, for a dual connectivity and/or multi-connectivity from the terminal device to a data network.
The method of claim 32, wherein the first data unit and the second data unit comprise same data information to be transmitted.
The method of claim 32, wherein the correlation of the first identifier and the second identifier is based on a third identifier of the first data unit in a second radio link protocol layer and a fourth identifier of the second data unit in the second radio link protocol layer, the second radio link protocol layer being a higher protocol layer than the first radio link protocol layer.
The method of claim 32, further comprising:

receiving, from the terminal device, a message indicating a difference between the first identifier and second identifier.
The method of claim 32, further comprising:

in response to receiving a request for the second data unit from the first network device, transmitting the second data unit to the first network device, the request being based on first identifier of the first data unit for the first network device.
The method of claim 32, further comprising:

transmitting, to the first network device, the second data unit; and

receiving, from the first network device, the first data unit.
The method of claim 37, further comprising:

determine whether the received first data unit comprises the same data information as the second data unit; and

in accordance with a determination that the received first data unit comprises the same data information as the second data unit, select any of the received first data unit and the second data unit for transmitting to the data network and remove the other data unit.
An apparatus implemented in a terminal device, comprising:

means for initiating, via a first network device and a second network device, respectively, a dual connectivity and/or multi-connectivity to a data network;

means for correlating a first data unit having a first identifier for the first network device with a second data unit having a second identifier for the second network device, the first identifier and the second identifier being used in a first radio link protocol layer; and

means for transmitting the first data unit with the correlated first identifier to the first network and transmit the second data unit with the correlated second identifier to the second network device.
An apparatus implemented in a first network device, comprising:

means for receiving, from a terminal device, a first data unit having a first identifier, the first data unit being correlated by the terminal device with a second data unit having a second identifier for a second network device, the first identifier and second identifier being used in a first radio link protocol layer; and

wherein the first network device and second network device are used, respectively, for a dual connectivity and/or multi-connectivity from the terminal device to a data network.
An apparatus implemented in a second network device, comprising:

means for receiving, from a terminal device, a second data unit having a second identifier, the second data unit being correlated by the terminal device with a first data unit having a first identifier for a first network device, the first identifier and second identifier being used in a first radio link protocol layer; and

wherein the first network device and second network device being used, respectively, for a dual connectivity and/or multi-connectivity from the terminal device to a data network.
A computer-readable storage medium having instructions stored thereon, the instructions, when executed on at least one processor, cause the least one processor to perform the method of any of claims 20-23, any of claims 24-31 or any of claims 32-38.