WO2020042113A1 - 一种数据传输方法及装置 - Google Patents

一种数据传输方法及装置 Download PDF

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Publication number
WO2020042113A1
WO2020042113A1 PCT/CN2018/103342 CN2018103342W WO2020042113A1 WO 2020042113 A1 WO2020042113 A1 WO 2020042113A1 CN 2018103342 W CN2018103342 W CN 2018103342W WO 2020042113 A1 WO2020042113 A1 WO 2020042113A1
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WIPO (PCT)
Prior art keywords
downlink data
message
terminal device
access network
network device
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PCT/CN2018/103342
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English (en)
French (fr)
Inventor
于映辉
王宏
王燕
罗林杰⋅奥黛尔
Original Assignee
华为技术有限公司
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Application filed by 华为技术有限公司 filed Critical 华为技术有限公司
Priority to PCT/CN2018/103342 priority Critical patent/WO2020042113A1/zh
Publication of WO2020042113A1 publication Critical patent/WO2020042113A1/zh

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/04—Wireless resource allocation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W74/00—Wireless channel access
    • H04W74/08—Non-scheduled access, e.g. ALOHA
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
    • Y02D30/00—Reducing energy consumption in communication networks
    • Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks

Definitions

  • the present application relates to the field of wireless communications, and in particular, to a data transmission method and device.
  • Narrow-band Internet of Things (NB-IoT) and machine type communication (MTC) continue to optimize the transmission of small data packets for the Internet of Things.
  • a new design using data transmission in the random access process is designed.
  • This kind of data transmission in the random access process is called early data transmission (EDT).
  • the existing random access procedure includes messages 1 (message 1 (MSG1) to 4 (message 4 (MSG4)).
  • SMSG1 messages 1
  • MSG4 messages 4
  • the first uplink data transmission occurs at the transmission time of message 5 (MSG5)
  • the first downlink data transmission occurs after MSG5.
  • the base station in order to implement uplink (UL) triggered EDT in MSG3, the base station will allocate a larger UL resource in message 2 (MSG2), which is message 3 (message 3, MSG3) Allocate a large UL resource.
  • MSG2 message 2
  • MSG3 message 3
  • Allocate a large UL resource For example, the minimum value of the UL resource is 320 bits and the maximum value is 1000 bits.
  • UE user equipment
  • CP service request control plane service request
  • the UE uses a larger UL resource allocated for MSG3 in order to support DL-triggered EDT, it will cause MSG3 padding problems and waste of UL resources, further causing the UE to increase power consumption due to multiple data transmissions.
  • the size of the MSG3 carrying the CP service request exceeds 88 bits, but it is still much smaller than the minimum message size allocated for MSG3, which is 320 bits.
  • the embodiments of the present application provide a data transmission method and device, which are used to solve the problems of resource waste and large power consumption of a terminal device in an EDT process triggered by DL.
  • an embodiment of the present application provides a data transmission method.
  • the method includes:
  • the access network device receives a first message from a control plane network element of the core network, where the first message includes an identification of the terminal device; the access network device sends a second message to the terminal device indicated by the identification of the terminal device.
  • the second message includes physical random access channel PRACH resource indication information corresponding to the terminal device; the access network device receives a random access message from the terminal device; the access network device determines the terminal device Sending the random access message using the PRACH resource indicated by the PRACH resource indication information, and sending downlink data to the terminal device.
  • the transmission delay of downlink data can be reduced, and early transmission of downlink data can be achieved.
  • the waste of resources in the EDT process triggered by DL in the prior art is avoided, and the power consumption of the terminal device can be reduced.
  • the first message includes downlink data indication information and / or the downlink data; or, before the access network device sends the downlink data to the terminal device, the method further includes: The access network device sends a third message to the core network control plane network element, the third message includes an identifier of the terminal device, and the third message is used to request the downlink data; the access network device Receiving a fourth message from the core network control plane network element, where the fourth message includes the downlink data.
  • the access network device can obtain downlink data in multiple ways.
  • the identifier of the terminal device is a temporary mobile user identifier S-TMSI
  • the first message or the fourth message includes a non-access layer protocol data unit NAS PDU, and the NAS PDU Including the downlink data.
  • the downlink data can be carried through the NAS PDU.
  • the sending of downlink data by the access network device to the terminal device includes: sending, by the access network device, a random access response message to the terminal device, and the random access response message Carry the downlink data.
  • the early data transmission of downlink data can be achieved through the random access response message, which further reduces the transmission delay of the downlink data.
  • the method before the access network device sends downlink data to the terminal device, the method further includes: the access network device receives the downlink data from a core network user plane network element.
  • the downlink data can be sent from the core network user plane network element to the access network device.
  • the sending the downlink data by the access network device to the terminal device includes: sending, by the access network device, a random access response message and the downlink data to the terminal device synchronously.
  • the data of the downlink data can be transmitted early, and the transmission delay of the downlink data can be further reduced.
  • the random access response message includes uplink resource indication information
  • the uplink resource indication information is used to instruct the terminal device to send to the access network device whether the terminal device successfully receives all
  • the time-frequency resources used in the response message of the downlink data are described.
  • the terminal device can feedback on whether the downlink data is successfully received on the allocated uplink resource.
  • the identifier of the terminal device is an S-TMSI and a first identifier, and the first identifier includes an identifier for obtaining a context of the terminal device;
  • the method further includes: the access network device sends a fifth message to the core network control plane network element, the fifth message includes the first identifier, and the fifth message is used for Request the context of the terminal device; the access network device receives a sixth message from the core network control plane network element, the sixth message includes the context of the terminal device; the context of the terminal device includes access Layer AS security context and / or bearer configuration parameters; the access network device generates an AS security key based on the AS security context, and / or the access network device establishes the access network based on the bearer configuration parameters Data bearing between the device and the terminal device.
  • the access network device can obtain the context of the terminal device from the core network control plane network element, generate the AS security key, and establish the data bearer.
  • the sixth message further includes a next hop link counter NCC;
  • the access network device generating an AS security key based on the AS security context includes: the access network device is based on The AS security context and the NCC generate an AS security key.
  • the AS security key can also be generated through the AS security context and the NCC.
  • the method further includes: the access network device encrypts the downlink data based on the AS security key to obtain the encrypted data; the access network device synchronizes to the terminal device Sending the random access response message and the downlink data includes: when the access network device sends the random access response message to the terminal device, sending the encrypted data through the data bearer.
  • the access network device encrypts the downlink data based on the AS security key, and sends the encrypted data to the terminal device through the established data bearer and the random access response message synchronously.
  • the downlink data indication information is single downlink data packet indication information.
  • the downlink data indication information is a single downlink data packet indication information, which can effectively save the transmission delay and power consumption of small data packets.
  • an embodiment of the present application provides a data transmission method.
  • the method includes:
  • the terminal device receives a second message from the access network device, and the second message includes PRACH resource instruction information corresponding to the terminal device; the terminal device uses the PRACH resource indicated by the PRACH resource instruction information to access the device.
  • the network device sends a random access message; the terminal device receives downlink data from the access network device.
  • the transmission delay of downlink data can be reduced, and early transmission of downlink data can be achieved.
  • the waste of resources in the EDT process triggered by DL in the prior art is avoided, and the power consumption of the terminal device can be reduced.
  • the receiving, by the terminal device, downlink data from the access network device includes: receiving, by the terminal device, a random access response message from the access network device, where the random access response message carries NAS PDU, the NAS PDU includes the downlink data.
  • the downlink data can be carried by the NAS PDU, the data of the downlink data can be transmitted early through the random access response message, which further reduces the transmission delay of the downlink data.
  • the method before the terminal device receives downlink data from the access network device, the method further includes: establishing, by the terminal device, the access network device and the terminal device based on the saved bearer configuration parameter.
  • the terminal device receives downlink data from the access network device, including: the terminal device synchronously receives a random access response message and the downlink data from the access network device, and the downlink data passes The data bearer carries.
  • it also includes:
  • the terminal device generates an AS security key based on the saved AS security context; the terminal device parses the downlink data based on the AS security key.
  • the random access response message further carries an NCC; the method further includes: the terminal device generating an AS security key based on the saved AS security context and the NCC;
  • the terminal device parses the downlink data based on the AS security key.
  • the terminal device can generate the AS security key based on different methods.
  • the random access response message carries uplink resource indication information
  • the uplink resource indication information is used to instruct the terminal device to send to the access network device whether the terminal device successfully receives all The time-frequency resource used in the response message of the downlink data
  • the method further includes: if the terminal device successfully parses the downlink data, the terminal device Sending a downlink data reception success response message to the access network device by using the time-frequency resource indicated by the uplink resource indication information; if the terminal device fails to parse the downlink data or the terminal device does not receive the downlink data Data, the terminal device uses the time-frequency resource indicated by the uplink resource indication information to send a downlink data reception failure response message to the access network device.
  • the terminal device can feedback on whether the downlink data is successfully received on the allocated uplink resource.
  • an embodiment of the present application provides a data transmission method.
  • the method includes: a core network control plane network element obtaining downlink data indication information; the core network control plane network element sends a first message to an access network device, and The first message includes an identification of the terminal device.
  • the transmission delay of downlink data can be reduced, and early transmission of downlink data can be achieved.
  • the waste of resources in the EDT process triggered by DL in the prior art is avoided, and the power consumption of the terminal device can be reduced.
  • the core network control plane network element acquiring downlink data indication information includes: the core network control plane network element receiving downlink data from the core network user plane network element to generate downlink data indication information; or The core network control plane network element receives downlink data indication information from the core network user plane network element.
  • the network element on the control plane of the core network can obtain downlink data indication information in different ways.
  • the downlink data indication information is single downlink data packet indication information.
  • the downlink data indication information is a single downlink data packet indication information, which can effectively save the transmission delay and power consumption of small data packets.
  • the first message includes downlink data indication information and / or downlink data indicated by the downlink data indication information; or, the core network control plane network element receives from the access network device A third message, the third message including an identifier of the terminal device, and the third message is used to request downlink data indicated by the downlink data indication information; the core network control plane network element reports to the access network The device sends a fourth message, where the fourth message includes the downlink data.
  • the core network control plane network element can send downlink data to the access network device in various ways.
  • the identifier of the terminal device is S-TMSI
  • the first message or the fourth message includes a NAS PDU
  • the NAS PDU includes the downlink data
  • the downlink data can be carried through the NAS PDU.
  • the method further includes: the core network control plane network element receives a third message from the access network device The third message includes an identifier of the terminal device, and the third message is used to request the downlink data indicated by the downlink data indication information; the core network control plane network element sends the first Seven messages, the seventh message is used to instruct the core network user plane network element to send the eighth message to the access network device, where the eighth message includes the downlink data.
  • the downlink data can be sent from the core network user plane network element to the access network device.
  • the identifier of the terminal device includes an S-TMSI and a first identifier, and the first identifier includes an identifier for obtaining a context of the terminal device; a network element on a control plane of the core network After sending the first message to the access network device, the method further includes: the core network control plane network element receiving a fifth message from the access network device, where the fifth message includes the first identifier, and the fifth The message is used to request the context of the terminal device; the core network control plane network element sends a sixth message to the access network device, where the sixth message includes the context of the terminal device and the context of the terminal device Include AS security context and / or bearer configuration parameters.
  • the context of the terminal device is sent to the access network device by the core network control plane network element.
  • the sixth message further includes an NCC.
  • an embodiment of the present application provides a data transmission method.
  • the method includes: an access network device receives a first message from a core network control plane network element, the first message includes an identifier of a terminal device, and the access The network device sends a second message to the terminal device indicated by the identifier of the terminal device, where the second message includes downlink resource indication information; the access network device sends a second message to the time-frequency resource indicated by the downlink resource indication information.
  • the terminal device sends downlink data.
  • the transmission delay of downlink data can be reduced, and early transmission of downlink data can be achieved.
  • the waste of resources in the EDT process triggered by DL in the prior art is avoided, and the power consumption of the terminal device can be reduced.
  • the second message further includes uplink resource indication information, and the uplink resource indication information is used to instruct the terminal device to send to the access network device whether the terminal device successfully receives the terminal device.
  • the time-frequency resource used by the response message of the downlink data is used to instruct the terminal device to send to the access network device whether the terminal device successfully receives the terminal device.
  • the terminal device can feedback on whether the downlink data is successfully received on the allocated uplink resource.
  • the first message includes downlink data packet indication information and / or the downlink data.
  • the identifier of the terminal device is S-TMSI
  • the first message includes a NAS PDU
  • the NAS PDU includes the downlink data
  • the downlink data can be carried through the NAS PDU.
  • the method before the access network device sends downlink data to the terminal device on the time-frequency resource indicated by the downlink resource indication information, the method further includes: the access network device sends the downlink data from the core network.
  • the user plane network element receives the downlink data.
  • the downlink data can be sent from the core network user plane network element to the access network device.
  • the identifier of the terminal device includes an S-TMSI and a first identifier, and the first identifier includes an identifier for obtaining a context of the terminal device;
  • the method further includes: the access network device sending a fifth message to the core network control plane network element, where the fifth message includes The first identifier and the fifth message are used to request a context of the terminal device; the access network device receives a sixth message from the core network control plane network element, and the sixth message includes the terminal
  • the context of the device; the context of the terminal device includes an AS security context and / or bearer configuration parameters; the access network device generates an AS security key based on the AS security context, and / or the access network device is based on all
  • the bearer configuration parameters establish a data bearer between the access network device and the terminal device.
  • the access network device can obtain the context of the terminal device from the core network control plane network element, generate the AS security key, and establish the data bearer.
  • the sixth message further includes NCC; the access network device generating an AS security key based on the AS security context includes: the access network device based on the AS security context and The NCC generates an AS security key.
  • the AS security key can also be generated through the AS security context and the NCC.
  • the method further includes: the access network device encrypts the downlink data based on the generated AS security key to obtain encrypted data; and the access network device is in the downlink Sending downlink data to the terminal device on the time-frequency resource indicated by the resource indication information includes: sending, by the access network device, the terminal device through the data bearer on the time-frequency resource indicated by the downlink resource indication information.
  • the encrypted data is not limited to: the access network device encrypts the downlink data based on the generated AS security key to obtain encrypted data; and the access network device is in the downlink Sending downlink data to the terminal device on the time-frequency resource indicated by the resource indication information includes: sending, by the access network device, the terminal device through the data bearer on the time-frequency resource indicated by the downlink resource indication information. The encrypted data.
  • the access network device encrypts the downlink data based on the AS security key, and sends the encrypted data to the terminal device on the time-frequency resource indicated by the downlink resource instruction information through the established data.
  • the downlink data indication information is single downlink data packet indication information.
  • an embodiment of the present application provides a data transmission method.
  • the method includes: a terminal device receiving a second message from an access network device, the second message including downlink resource indication information; and the terminal device in the downlink Receiving downlink data from the access network device on the time-frequency resource indicated by the resource indication information.
  • the transmission delay of downlink data can be reduced, and early transmission of downlink data can be achieved.
  • the waste of resources in the EDT process triggered by DL in the prior art is avoided, and the power consumption of the terminal device can be reduced.
  • the second message further includes uplink resource indication information, and the uplink resource indication information is used to instruct the terminal device to send to the access network device whether the terminal device successfully receives the terminal device.
  • the time-frequency resource used by the response message of the downlink data after the terminal device receives the downlink data from the access network device on the time-frequency resource indicated by the downlink resource indication information, the method further includes: if the terminal device The downlink data is successfully parsed, and the terminal device uses the time-frequency resource indicated by the uplink resource indication information to send a downlink data reception success response message to the access network device; if the terminal device parses the downlink data Failure or the terminal device does not receive the downlink data, the terminal device uses the time-frequency resource indicated by the uplink resource indication information to send a downlink data reception failure response message to the access network device.
  • the terminal device can feedback on whether the downlink data is successfully received on the allocated uplink resource.
  • the receiving, by the terminal device, downlink data from the access network device on the time-frequency resource indicated by the downlink resource indication information includes: the terminal device indicating in the downlink resource indication information And receiving a NAS PDU from the access network device on the time-frequency resource, and the NAS PDU includes the downlink data.
  • the downlink data can be carried through the NAS PDU.
  • the method before the terminal device receives downlink data from the access network device on the time-frequency resource indicated by the downlink resource indication information, the method further includes: the terminal device is based on the saved bearer configuration Parameter establishing a data bearer between the access network device and the terminal device; the terminal device receiving downlink data from the access network device on the time-frequency resource indicated by the downlink resource indication information, including: the terminal The device receives downlink data from the access network device on the time-frequency resource indicated by the downlink resource indication information, and the downlink data is carried by the data bearer.
  • the downlink data can be carried through the data bearer.
  • the method further includes: the terminal device generating an AS security key based on the saved AS security context; and the terminal device parsing the downlink data based on the AS security key.
  • the second message also carries NCC; the method further includes: the terminal device generates an AS security key based on the saved AS security context and the NCC; the terminal device is based on all The AS security key parses the downlink data.
  • the terminal device can generate the AS security key based on different methods.
  • a device in a sixth aspect, has a function for realizing the behavior of an access network device or terminal device or a control plane network element of a core network in the above method aspect, and includes components corresponding to the steps or functions described in the above method aspect.
  • the steps or functions may be implemented by software, or by hardware (such as a circuit), or by a combination of hardware and software.
  • the above device includes one or more processors and a communication unit.
  • the one or more processors are configured to support the apparatus to perform a corresponding function of the terminal device in the foregoing method.
  • the communication unit is configured to support the device to communicate with other devices to implement receiving and / or transmitting functions.
  • the device may further include one or more memories, and the memory is configured to be coupled to the processor, and stores the program instructions and / or data necessary for the device.
  • the one or more memories may be integrated with the processor, or may be separately provided from the processor. This application is not limited.
  • the device may be an Internet of Things terminal device and the like, and the communication unit may be a transceiver or a transceiver circuit.
  • the transceiver may be an input / output circuit or an interface.
  • the device may also be a communication chip.
  • the communication unit may be an input / output circuit or an interface of a communication chip.
  • the device includes a transceiver, a processor, and a memory.
  • the processor is used to control the transceiver or the input / output circuit to send and receive signals
  • the memory is used to store a computer program
  • the processor is used to run the computer program in the memory, so that the device executes the second aspect or any one of the second aspect
  • the method completed by the terminal device in the implementation manner may be implemented, or the apparatus is caused to execute the method completed by the terminal device in any of the fifth aspect or the fifth implementation manner.
  • the above device includes one or more processors and a communication unit.
  • the one or more processors are configured to support the apparatus to perform a corresponding function of an access network device in the foregoing method.
  • the communication unit is configured to support the device to communicate with other devices to implement receiving and / or transmitting functions.
  • the apparatus may further include one or more memories, where the memories are configured to be coupled to the processor, and store the program instructions and / or data necessary for the access network device.
  • the one or more memories may be integrated with the processor, or may be separately provided from the processor. This application is not limited.
  • the device may be an eNB, a gNB, or the like, and the communication unit may be a transceiver or a transceiver circuit.
  • the transceiver may be an input / output circuit or an interface.
  • the device may also be a communication chip.
  • the communication unit may be an input / output circuit or an interface of a communication chip.
  • the device includes a transceiver, a processor, and a memory.
  • the processor is used to control the transceiver or the input / output circuit to send and receive signals
  • the memory is used to store a computer program
  • the processor is used to run the computer program in the memory, so that the device executes any of the first aspect or the first aspect
  • the above device includes one or more processors and a communication unit.
  • the one or more processors are configured to support the device to perform a corresponding function of a core network control plane network element in the foregoing method.
  • the communication unit is configured to support the device to communicate with other devices to implement receiving and / or transmitting functions.
  • the device may further include one or more memories, where the memories are configured to be coupled to the processor, and the memories store program instructions and / or data necessary for the core network control plane network element.
  • the one or more memories may be integrated with the processor, or may be separately provided from the processor. This application is not limited.
  • the device may be an MME, an AMF, or the like, and the communication unit may be a transceiver or a transceiver circuit.
  • the transceiver may be an input / output circuit or an interface.
  • the device may also be a communication chip.
  • the communication unit may be an input / output circuit or an interface of a communication chip.
  • the device includes a transceiver, a processor, and a memory.
  • the processor is used to control the transceiver or the input / output circuit to send and receive signals
  • the memory is used to store the computer program
  • the processor is used to run the computer program in the memory, so that the device executes the third aspect or any one of the third aspect.
  • a system which includes the foregoing terminal device, access network device, and core network control plane network element.
  • a computer-readable storage medium for storing a computer program, the computer program including instructions for performing the first aspect or the method in any possible implementation manner of the first aspect, or for Instructions for executing the second aspect or the method in any one of the possible implementations of the second aspect, or instructions for performing the third aspect or the methods in any of the possible implementations of the third aspect, or for performing the first
  • a computer program product includes computer program code that, when the computer program code runs on a computer, causes the computer to execute any one of the first aspect or the first aspect.
  • the method in the possible implementation manner, or causes the computer to execute the method in any of the second aspect or the second aspect, or the computer to execute the method in the third aspect or any of the third aspect.
  • FIG. 1 is a schematic diagram of an existing random access process in the present application
  • FIG. 2 is a schematic diagram of a system architecture of a 4G system in this application.
  • FIG. 3 is a schematic diagram of a system architecture of a 5G system in this application.
  • FIG. 4 is a schematic diagram of an IoT business scenario in this application.
  • FIG. 5 is a specific flowchart of an existing DL triggered EDT in this application.
  • FIG. 6 is one of the overview flowcharts of the data transmission method in this application.
  • FIG. 7 is one of the specific flowcharts of early transmission of CP downlink data in this application.
  • FIG. 8 is one of the specific flowcharts of early transmission of UP downlink data in this application.
  • FIG. 10 is the second specific flowchart of early transmission of CP downlink data in this application.
  • FIG. 11 is the second specific flowchart of early transmission of UP downlink data in this application.
  • FIG. 12 is one of the schematic structural diagrams of a data transmission device in this application.
  • FIG. 13 is a second schematic structural diagram of a data transmission device in this application.
  • FIG. 2 is a schematic diagram of a specific system architecture applicable to an embodiment of the present application.
  • the system architecture of the 4G system includes two parts: a radio access network and a core network.
  • the radio access network is an evolved universal terrestrial radio access network (E-UTRAN). Used to implement wireless access related functions.
  • the core network includes a mobility management entity (MME), a serving gateway (SGW), a packet data network gateway (PGW), and the like.
  • MME mobility management entity
  • SGW serving gateway
  • PGW packet data network gateway
  • the MME is mainly responsible for mobility management and session management of the control plane.
  • SGW is a user plane functional entity that completes the routing and forwarding of packet data.
  • PGW is the gateway to the external data network.
  • the S-GW and P-GW can be deployed together, and are generally collectively referred to as a gateway.
  • the UE may access the external PDN by establishing a connection from the UE to the E-UTRAN to the SGW to the PGW to a packet data network (PDN).
  • PDN packet data network
  • FIG. 3 is a schematic diagram of another specific system architecture applicable to an embodiment of the present application.
  • the wireless access network is a next generation wireless access network (NG-RAN), which is used to implement functions related to wireless access.
  • the core network includes: access and mobility management (AMF) network elements, session management (SMF) network elements, user plane function (UPF) network elements, etc. .
  • AMF access and mobility management
  • SMF session management
  • UPF user plane function
  • the AMF network element is mainly responsible for mobility management.
  • AMF network elements can also be called AMF equipment or AMF entities.
  • the SMF network element is mainly responsible for session management.
  • the SMF network element may also be called an SMF device or an SMF entity.
  • the UPF is mainly responsible for processing user packets, such as forwarding.
  • the UE can access the DN by establishing a session from the UE to the NG-RAN to the UPF to a data network (DN).
  • DN data network
  • FIG. 2 and FIG. 3 are merely examples, and the system architecture applicable to the embodiments of the present application may not be limited to the above two specific system architectures.
  • the access network device referred to in the embodiments of the present application refers to a device that provides wireless access for terminal devices, and may include various forms of base stations, such as macro base stations, micro base stations (also called small stations), and relay stations. Access points, eNodeBs, wireless fidelity access points (WiFi AP), worldwide interoperability for microwave access (microwave access base station, WiMAX), etc. In different systems, the names of devices with wireless access functions may be different. For example, in a 4G system, the access network device may be called an evolved NodeB (evolved NodeB, eNB, or eNodeB). In a 5G system, an access network device may be called a gNB (gNodeB).
  • gNodeB evolved NodeB
  • gNodeB gNodeB
  • the terminal devices involved in the embodiments of the present application are mainly IoT terminal devices, such as fire detection sensors, smart water / electric meters, factory monitoring equipment, smart homes, automobiles, wearable devices, etc.
  • the core network control plane device referred to in the embodiments of the present application refers to a control plane functional entity in the core network in the system architecture.
  • the name of the control plane device may be different in different systems. For example, in a 4G system, the control plane device is called an MME, and in a 5G system, the control plane device is called an AMF.
  • the core network user plane device referred to in the embodiments of the present application refers to a user plane functional entity in the core network in the system architecture.
  • the names of user plane devices may be different.
  • SGW user plane devices
  • UPF user plane devices
  • the main business scenario applicable to the embodiment of the present application is a business scenario of the Internet of Things, as shown in FIG. 4.
  • the Internet of Things as a component of the fifth generation of mobile communications (5G), has a rapidly growing market demand. It is predicted that by 2022, the number of 5G Internet of Things connections will reach 18 billion.
  • the 3GPP standard has been based on the cellular network, and proposed solutions for the characteristics of the Internet of Things, such as the NB-IoT network and the MTC network. Both use the characteristics of narrowband technology to carry IoT services.
  • the NB-IoT network uses a new air interface technology that is independent of the existing cellular network.
  • the terminal equipment costs are lower, and the supported speed and mobility are lower.
  • the MTC network is part of the traditional cellular network, the terminal equipment costs are higher, and the supported rates and mobility are higher.
  • the services and terminal equipment of the Internet of Things have the following characteristics:
  • NB-IoT services generate smaller data packets and are generally not very sensitive to latency.
  • NB-IoT Low cost requirements for terminal equipment.
  • NB-IoT compared with the terminal equipment of the existing cellular network, NB-IoT requires the cost of the terminal equipment to be lower, and also requires the implementation complexity of the terminal equipment to be lower, so as to achieve the mass deployment of the terminal equipment.
  • NB-IoT Low power consumption requirements for terminal equipment.
  • NB-IoT requires lower power consumption of terminal equipment, thereby saving the battery power of terminal equipment, ensuring the long standby time of terminal equipment, and thereby saving the labor cost of battery replacement.
  • FIG. 5 it is a specific process of EDT triggered by DL in the prior art.
  • the eNB broadcasts EDT configuration information. These include an uplink data volume control threshold that allows the use of EDT for each coverage level broadcast, and EDT physical random access channel (PRACH) resources.
  • EDT configuration information include an uplink data volume control threshold that allows the use of EDT for each coverage level broadcast, and EDT physical random access channel (PRACH) resources.
  • PRACH physical random access channel
  • S502 The UE receives a paging message from the eNB.
  • S503 The UE sends a random access message to the eNB.
  • the UE determines whether to use EDT according to its own coverage level and the amount of uplink data to be sent. If the amount of uplink data to be sent is greater than the uplink data amount control threshold corresponding to its own coverage level , A traditional random access process is initiated. If the amount of uplink data to be sent is less than or equal to the uplink data amount control threshold corresponding to its own coverage level, an EDT process is initiated. When the UE determines to initiate the EDT process, the UE uses the EDT and PRACH resources to initiate random access according to the EDT configuration information broadcast by the eNB, and further indicates that the random access is an EDT process.
  • the amount of uplink data to be sent here refers to the data amount of MSG3.
  • the eNB sends a random access response message (RAR) to the UE.
  • RAR random access response message
  • the RAR carries resource indication information for uplink data transmission, for example, uplink scheduling grant (UL grant).
  • MSG3 The UE sends MSG3 to the eNB.
  • MSG3 carries the NAS PDU and S-TMSI.
  • the NAS PDU includes the CP service request.
  • the UE sends MSG3 by using the resource indicated by the resource indication information carried by the RAR for uplink data transmission.
  • the eNB sends MSG4 to the UE.
  • the MSG4 carries a NAS PDU, and the NAS PDU includes downlink data.
  • the eNB sends the NAS PDU to the MME.
  • the MME sends downlink data to the UE through the eNB.
  • the eNB may also allow the UE to enter an idle state after receiving downlink data.
  • the UE sends the MSG3 using the resource indicated by the resource indication information for uplink data transmission, and the resource indicated by the resource indication information for uplink data transmission is generally large, so it will bring MSG3
  • the filling problem and waste of resources further increase the power consumption of the terminal device due to multiple data transmissions.
  • an embodiment of the present application provides a data transmission method, which is used to solve the problem of resource waste in the EDT process triggered by DL, and to reduce the power consumption of the terminal device.
  • the method includes:
  • Step 601 The network element on the control plane of the core network obtains downlink data indication information.
  • the core network control plane network element may receive downlink data from the core network user plane network element to generate downlink data indication information; or the core network control plane network element directly receives the downlink data indication information from the core network user plane network element.
  • the downlink data indication information is single downlink data packet indication information.
  • Step 602 The network element on the control plane of the core network sends a first message to the access network device.
  • the first message includes an identification of the terminal device.
  • the first message may further include downlink data indication information.
  • the first message may be a paging message.
  • the identification of the terminal device may include a SAE-temporary mobile subscriber identity (S-TMSI), or the identification of the terminal device may include an S-TMSI and a first identification, where the first identification includes a method for obtaining The identifier of the context of the terminal device.
  • the first identifier may be an identifier allocated by a core network control plane network element.
  • S1APID is an identifier allocated by the MME, and the identifier is used to obtain the context of the UE from the MME.
  • the first identifier may be an identifier assigned by an access network device, for example, a resume identifier is an identifier assigned by a base station that last communicated with the UE, and the identifier is a base station that last communicated with the UE at
  • the identity can be used as an S1AP IE or carried in a radio resource control container (radio resource control container) to ensure that the identity is not resolved by the MME. This identifier is used to obtain the context from the base station that last communicated with the UE.
  • Step 603 After the access network device receives the first message from the control plane network element of the core network, the access network device sends the second message to the terminal device indicated by the terminal device identifier.
  • the second message may be a paging message.
  • the second message includes PRACH resource indication information corresponding to the terminal device.
  • the PRACH resource refers to a preamble allocated to a terminal device or a time-frequency resource used for random access allocated to the terminal device or a preabmle and time-frequency resource used for random access allocated to the terminal.
  • the base station establishes a PRACH resource mapping information for each S-TMSI, so that the base station can determine which UE accesses the network according to the PRACH resource used by the received random access message.
  • Step 604 After the terminal device receives the second message from the access network device, the terminal device sends a random access message to the access network device by using the PRACH resource indicated by the PRACH resource instruction information.
  • Step 605 After the access network device receives the random access message from the terminal device, the access network device determines that the terminal device sends a random access message using the PRACH resource indicated by the PRACH resource instruction information, and sends downlink data to the terminal device.
  • the access network equipment uses a cell-radio network temporary identifier (C-RNTI) or a random access wireless network temporary identifier (RA-RNTI)
  • C-RNTI cell-radio network temporary identifier
  • RA-RNTI random access wireless network temporary identifier
  • the access network device Before the access network device sends downlink data to the terminal device, the access network device can obtain, but is not limited to, the following methods:
  • the first message includes downlink data.
  • the core network control plane network element may receive downlink data from the core network user plane network element, generate downlink data indication information, and carry the downlink data in the first message when sending the first message to the access network device.
  • Method two the access network device receives downlink data from the core network control plane network element.
  • the access network device sends a third message to the core network control plane network element, the third message includes the identity of the terminal device, and the third message is used to request the downlink data .
  • the access network device receives a fourth message from the core network control plane network element, and the fourth message includes downlink data.
  • Method 3 The access network device receives downlink data from a user plane network element of the core network.
  • the access network device sends a third message to the core network control plane network element, the third message includes the identity of the terminal device, and the third message is used to request the downlink data .
  • the core network control plane network element sends a seventh message to the core network user plane network element.
  • the seventh message is used to instruct the core network user plane network element to send an eighth message to the access network device.
  • the eighth message includes downlink data.
  • the access network device may obtain the downlink data by using the foregoing manner 1 or manner 2.
  • the first message or the fourth message includes a non-access stratum protocol data unit (NAS PDU), and the NAS PDU includes downlink data.
  • the access network device sends a random access response message to the terminal device, and the random access response message carries downlink data. It should be understood that, at this time, the random access response message includes a NAS PDU, and the NAS PDU includes downlink data.
  • the access network device may obtain the downlink data by using the foregoing manner 1, manner 2, or manner 3. Further, for step 605, the access network device sends a random access response message and downlink data to the terminal device. At this time, when the access network device sends a random access response message to the terminal device, it sends downlink data through the data bearer. Therefore, for scenario 2, before the access network device sends downlink data to the terminal device, the access network device needs to establish a data bearer between the access network device and the terminal device based on the bearer configuration parameters. Therefore, the access network device also needs to obtain the context of the terminal device.
  • the context of the terminal device that the access network device needs to obtain may include the entire content of the terminal device context, and may also include at least the access stratum (AS) security context and / or bearer configuration parameters. If the context of the terminal device does not include bearer configuration parameters, the access network device may use the default bearer configuration parameters to establish a data bearer between the access network device and the terminal device.
  • AS access stratum
  • the access network device when the first identifier is an identifier allocated by a core network control plane network element, the access network device sends a fifth message to the core network control plane network element, the fifth message includes the first identifier, and the fifth message is used for Request the context of the end device.
  • the access network device receives a sixth message from the core network control plane network element, and the sixth message includes the context of the terminal device.
  • the sixth message further includes a next hop linking counter (NCC).
  • NCC next hop linking counter
  • the access network device may obtain the context of the terminal device from other access network devices. For example, when the first identifier is resume ID, if the base station that last communicated with the UE is the same as the base station that currently receives the first message, the base station that currently receives the first message saves the context of the UE. Is different from the base station that currently receives the first message, the base station that currently receives the first message obtains the context of the UE from the base station that last communicated with the UE. For example, the base station that currently receives the first message sends a ninth message to the base station that last communicated with the UE, and the ninth message includes the context request message of the UE. Then, the base station that currently receives the first message receives the tenth message from the base station that last communicated with the UE, and the tenth message includes the context of the UE.
  • the access network device After the access network device obtains the context of the terminal device, the access network device generates an AS security key based on the AS security context, and / or establishes a data bearer between the access network device and the terminal device based on the bearer configuration parameters.
  • the sixth message further includes an NCC
  • the access network device generates an AS security key based on the AS security context and the NCC.
  • the access network device encrypts the downlink data based on the AS security key to obtain the encrypted data. Finally, when the access network device sends a random access response message to the terminal device, the encrypted downlink data is sent through the data bearer.
  • the terminal device before the terminal device receives downlink data from the access network device, the terminal device establishes a data bearer between the access network device and the terminal device based on the saved bearer configuration parameters. After the terminal device receives the downlink data from the access network device, the terminal device parses the downlink data based on the AS security key, where the AS security key is generated by the terminal device based on the saved AS security context. Optionally, if the random access response message also carries the NCC, the AS security key is generated by the terminal device based on the saved AS security context and the NCC.
  • the random access response message includes uplink resource indication information
  • the uplink resource indication information is used to instruct the terminal device to send to the access network device whether the terminal device has successfully received the downlink data Time-frequency resources used by the response message.
  • the terminal device After the terminal device receives downlink data from the access network device, if the terminal device parses the downlink data successfully, the terminal device uses the time-frequency resource indicated by the uplink resource instruction information to send a downlink data reception success response message to the access network device; if The terminal device fails to parse the downlink data or the terminal device does not receive the downlink data, and the terminal device uses the time-frequency resource indicated by the uplink resource instruction information to send a downlink data reception failure response message to the access network device.
  • the above-mentioned two types of response messages may be the response of the physical layer whether the class is correctly received or the response of the application layer, depending on the size of the uplink resource allocated by the access network device.
  • the terminal device After the terminal device receives the downlink data, if the terminal device needs to send the uplink data, it can adopt but not limited to the following design to perform ULEDT after receiving the downlink data:
  • the terminal device may send a downlink data reception success response message and uplink data to the access network device on the time-frequency resource indicated by the uplink resource indication information.
  • the uplink data here may be a single uplink data packet.
  • the access network device can also send an eleventh message to the terminal device. The eleventh message is used to release the terminal device to an idle state or to establish / restore the connection of the terminal device to the connected state.
  • the eleventh message may also carry downlink data.
  • the downlink data here may be a single downlink data packet.
  • the terminal device after the terminal device receives the downlink data, the early data transmission of the uplink data can be further realized, and when the eleventh message is used to release the terminal device to an idle state, the power consumption of the terminal device can be reduced .
  • the eleventh message when the eleventh message also carries downlink data, it can better meet the transmission requirements of downlink data.
  • the terminal device may send a downlink data reception success response message and a UL EDT request message to the access network device on the time-frequency resources indicated by the uplink resource indication information, and the UL EDT request message is used to request access Network access equipment allocates uplink resources for UL EDT for terminal equipment.
  • the access network device can allocate uplink resources for the terminal device to the ULEDT.
  • the terminal equipment sends uplink data to the access network equipment on the uplink resources allocated by the access network equipment for UL EDT.
  • the access network device can also send an eleventh message to the terminal device.
  • the eleventh message is used to release the terminal device to an idle state or to establish / restore the connection of the terminal device. To connected state.
  • the eleventh message may also carry downlink data. Therefore, through the above design, after the terminal device receives the downlink data, it can request UL EDT to further transmit the data of the uplink data early. When the eleventh message is used to release the terminal device to the idle state, the terminal can be reduced. The power consumption of the device. In addition, when the eleventh message also carries downlink data, it can better meet the transmission requirements of downlink data.
  • the core network control plane network element obtains downlink data indication information and sends a first message to the access network device. After receiving the first message, the access network device receives the first message.
  • the second message sent to the terminal device carries indication information of the PRACH resource allocated for the terminal device.
  • the access network device determines that the terminal device uses the PRACH resource indicated by the PRACH resource instruction information to send a random access message, it sends downlink data to the terminal device. Therefore, by using the above method, the transmission delay of downlink data can be reduced, and early transmission of downlink data can be achieved. At the same time, the waste of resources in the EDT process triggered by DL in the prior art is avoided, and the power consumption of the terminal device can be reduced.
  • the SGW sends a downlink data notification (Downlink data notification) to the MME.
  • the downlink data notification includes downlink data and / or single downlink data packet indication information.
  • the MME sends a paging message to the eNB.
  • the paging message includes S-TMSI.
  • the paging message includes single downlink data packet indication information.
  • the paging message sent by the MME to the eNB may also include downlink data.
  • the paging message includes a NAS PDU and the NAS PDU includes downlink data. Therefore, S706 and S707 are optional steps. When the paging message sent by the MME to the eNB includes downlink data, S706 and S707 need not be performed.
  • the eNB sends a paging message to the UE.
  • the paging message includes PRACH resource indication information corresponding to the S-TMSI.
  • the eNB allocates a corresponding PRACH resource for each S-TMSI, that is, establishes PRACH resource mapping information for each S-TMSI, so that the eNB can determine which one based on the PRACH resource used by the received random access message.
  • the UE accesses the network.
  • the PRACH resource may be a code, such as a preamble, and / or a time-frequency resource.
  • S704 The UE sends a random access message to the eNB based on the PRACH resource indicated by the PRACH resource indication information in the paging message sent by the eNB.
  • the eNB receives a random access message from the UE, determines that the UE sends a random access message using the PRACH resource indicated by the PRACH resource instruction information, and then determines the UE that initiates random access, that is, the eNB determines that the UE is a UE that successfully receives a paging message.
  • S706 The eNB sends an S1 message to the MME, where the S1 message is used to request a downlink data PDU from the MME.
  • the S1 message here may be a UE initial message (UE initial message), which includes an identity of the UE.
  • the eNB sets the length of the NAS PDU to 0, and other information elements (IE) can be set normally.
  • the S1 message here may also be a new S1 message, which includes the identifier of the UE, and the new S1 message is used to request the downlink data required by the UE corresponding to the identifier.
  • the MME sends an S1 downlink message to the eNB.
  • the message may be connection establishment instruction information or a downlink NAS transmission message, which includes a NAS PDU, and the NAS PDU includes downlink data.
  • the MME receives the downlink data from the SGW after receiving the S1 message sent by the eNB in S706.
  • the MME sends a bearer modification request message to the SGW to establish the user plane path, and receives downlink data from the SGW after the user plane path is successfully established; After the user plane path has been established, the MME can receive downlink data directly from the SGW.
  • S706 and S707 are operations that need to be performed when the paging message sent by the MME to the eNB does not include downlink data.
  • S706 and S707 may be performed after S705, that is, after the eNB determines that the UE initiates random access, the eNB requests the MME for downlink data.
  • S706 and S707 can be performed before S704 or after S704 and before receiving a random access message, that is, the eNB first requests downlink data from the MME, and then the eNB determines that the UE initiates random access, which is not limited in this application.
  • the eNB sends a random access response message to the UE.
  • the random access response message includes a NAS PDU and a UL grant.
  • the NAS PDU includes downlink data.
  • the NAS PDU is scrambled using C-RNTI or RA- RNTI is scrambled.
  • the resources indicated by the UL grant are used by the UE for uplink feedback on whether the NAS PDU was successfully received.
  • the NAS PDU may be multiplexed with the random access response message and transmitted in one transmission block.
  • the UE After the UE receives the random access response message from the eNB, if the UE successfully parses the NAS PDU in the random access response message, the UE sends a downlink data reception success response message to the eNB on the resource indicated by the UL grant. If the resource indicated by the UL grant is sufficiently large, the UE may also send the S-TMSI of the UE on the resource indicated by the UL grant.
  • the UE if the UE fails to parse the downlink data or the UE does not receive the downlink data, the UE sends a downlink data reception failure response message to the eNB on the resource indicated by the UL grant. This situation is not shown in FIG. 7.
  • the early transmission of downlink data is realized through MSG4.
  • Early transmission can further reduce the transmission delay of downlink data, and at the same time avoid the waste of resources in the EDT process triggered by DL in the prior art, and can reduce the power consumption of terminal equipment.
  • FIG. 8 it is a specific process of early transmission of UP downlink data.
  • the SGW sends a downlink data notification to the MME.
  • the downlink data notification includes downlink data and / or single downlink data packet indication information.
  • the MME sends a paging message to the eNB.
  • the paging message includes an S-TMSI and a first identifier, where the first identifier is a resume ID or a S1 AP ID.
  • the paging message includes single downlink data packet indication information.
  • the paging message sent by the MME to the eNB may also include downlink data.
  • the eNB sends a paging message to the UE.
  • the paging message includes PRACH resource indication information corresponding to the S-TMSI.
  • S804 The UE sends a random access message to the eNB based on the PRACH resource indicated by the PRACH resource indication information in the paging message sent by the eNB.
  • the eNB receives a random access message from the UE, determines that the UE sends the random access message using the PRACH resource indicated by the PRACH resource instruction information, and then determines the UE that initiates random access, that is, the eNB determines that the UE is a UE that successfully receives the paging message.
  • the eNB sends an S1 message to the MME, where the S1 message is used to request downlink data from the MME.
  • the S1 message may be a new S1 message, such as a downlink data request message. Alternatively, the S1 message may use other existing uplink S1 messages.
  • S807a If the MME obtains the downlink data in S801, the MME sends the downlink data to the eNB. Exemplarily, the MME sends an S1 downlink message to the eNB, which includes downlink data.
  • S807b1 If the MME does not obtain downlink data at S801, the MME sends a bearer modification request message to the SGW, where the bearer modification request message includes routing information of the eNB and is used to instruct the SGW to send downlink data to the eNB.
  • the SGW may also send a bearer modification response message to the MME after receiving the bearer modification request message, this step is not shown in FIG. 8.
  • the SGW sends downlink data to the eNB.
  • S807a, S807b1 and S807b2 are two different schemes. Regarding the execution order of S806, S807a, S807b1, S807b2, and S808, in one example, S806, S807a, and S808 are executed sequentially, and in another example, S806, S807b1, S807b2, and S808 are executed sequentially. In addition, if the paging message sent by the MME to the eNB includes downlink data, S806, S807a or S806, S807b1, and S807b2 need not be performed.
  • the eNB sends an S1 message to the MME.
  • the S1 message is used to request the context of the UE from the MME.
  • the S1 message includes the S1 AP ID.
  • S806 and S808 may be combined into one step, that is, the S1 message is used to request downlink data from the MME and also to request the context of the UE from the MME.
  • the current eNB saves the context of the UE and does not need to obtain the context of the UE from other network elements. If the eNB that communicated with the UE last time is different from the current eNB, the current eNB obtains the context of the UE from the eNB that communicated with the UE last time, which is omitted here and not shown in FIG. 8. Exemplarily, the current eNB sends an X2 message to the eNB that last communicated with the UE, which includes a context request message of the UE. The current eNB receives an X2 message from the eNB that last communicated with the UE, which includes the context of the UE.
  • the MME sends the context of the UE to the eNB.
  • the UE's context includes at least the AS security context and bearer configuration parameters.
  • the MME when the MME sends the context of the UE to the eNB, it may also send NCC synchronously.
  • the eNB generates an AS security key based on the AS security context, and establishes a data bearer between the eNB and the UE based on the bearer configuration parameters.
  • the eNB generates an AS security key based on the AS security context and the NCC.
  • the eNB sends a random access response message and downlink data to the UE. At this time, the eNB sends downlink data through the data bearer.
  • the random access response message may include UL grant, and the resource indicated by the UL grant is used by the UE to perform uplink feedback on whether the downlink data is successfully received.
  • the random access response message may further include an NCC.
  • the UE After the UE receives the random access response message and the downlink data from the eNB, if the UE successfully parses the downlink data according to the AS security key, the UE sends a downlink data reception success response message to the eNB on the resource indicated by the UL grant. If the resource indicated by the UL grant is sufficiently large, the UE may also send the S-TMSI of the UE on the resource indicated by the UL grant.
  • the UE sends a downlink data reception failure response message to the eNB on the resource indicated by the UL grant.
  • the UE generates an AS security key based on the AS security context, and establishes a data bearer between the eNB and the UE based on the bearer configuration parameters.
  • the random access response message may further include an NCC, and the UE generates an AS security key based on the AS security context and the NCC.
  • each step in the method flow shown in FIG. 8 may have other execution orders.
  • the eNB first obtains the context of the UE from the MME, and then obtains the downlink data from the MME.
  • the eNB adjust the execution order of certain steps or combine and execute certain steps should not be considered to be beyond the scope of this application.
  • early data transmission of downlink data is realized through MSG4.
  • synchronous transmission of MSG2 and downlink data can realize early data transmission of downlink data, which can further It reduces the transmission delay of downlink data, avoids the waste of resources in the EDT process triggered by DL in the prior art, and can reduce the power consumption of terminal equipment.
  • An embodiment of the present application provides a data transmission method, which is used to solve a problem of resource waste in a DL-triggered EDT process, and to reduce power consumption of a terminal device. As shown in Figure 9, the method includes:
  • Step 901 The network element on the control plane of the core network obtains downlink data indication information.
  • the core network control plane network element may receive downlink data from the core network user plane network element to generate downlink data indication information; or the core network control plane network element directly receives the downlink data indication information from the core network user plane network element.
  • the downlink data indication information is single downlink data packet indication information.
  • Step 902 The core network control plane network element sends a first message to the access network device.
  • the first message includes an identification of the terminal device.
  • the first message includes downlink data indication information.
  • the first message may be a paging message.
  • the identifier of the terminal device may include S-TMSI, or the identifier of the terminal device may include S-TMSI and a first identifier, where the first identifier includes an identifier for obtaining a context of the terminal device.
  • the first identifier may be an identifier allocated by a core network control plane network element.
  • S1APID is an identifier allocated by the MME, and the identifier is used to obtain the context of the UE from the MME.
  • the first identifier may be an identifier assigned by an access network device, for example, resumeID is an identifier assigned by a base station that last communicated with the UE, and the identifier is sent by the base station that last communicated with the UE to the MME. If the UE carries the MME in the context, the identifier can be used as the S1AP or IE in the RRC container to ensure that the identifier is not parsed by the MME. The identifier is used to obtain the context from the base station that last communicated with the UE.
  • Step 903 After the access network device receives the first message from the core network control plane network element, the access network device sends the second message to the terminal device indicated by the terminal device's identifier.
  • the second message may be a paging message.
  • the second message includes downlink resource indication information.
  • Step 904 The access network device sends downlink data to the terminal device on the time-frequency resource indicated by the downlink resource indication information.
  • the access network device uses the paging-radio network temporary identifier (P-RNTI) or the RNTI allocated by the access network device to scramble the downlink data.
  • P-RNTI paging-radio network temporary identifier
  • the access network device sends the scrambled downlink data to the terminal device.
  • the access network device Before the access network device sends downlink data to the terminal device, the access network device can obtain, but is not limited to, the following methods:
  • the first message includes downlink data.
  • the core network control plane network element may receive downlink data from the core network user plane network element, generate downlink data indication information, and carry the downlink data in the first message when sending the first message to the access network device.
  • Method 2 The access network device receives downlink data from a user plane network element of the core network.
  • the access network device sends a third message to the core network control plane network element, the third message includes the identity of the terminal device, and the third message is used to request the downlink data .
  • the core network control plane network element sends a seventh message to the core network user plane network element.
  • the seventh message is used to instruct the core network user plane network element to send an eighth message to the access network device.
  • the eighth message includes downlink data.
  • the access network device may obtain the downlink data by using the foregoing manner 1.
  • the first message includes a NAS PDU
  • the NAS PDU includes downlink data.
  • the access network device sends a NAS PDU to the terminal device, where the NAS PDU includes downlink data.
  • the access network device may obtain the downlink data by using the foregoing manner 1 or manner 2. Further, for step 904, the access network device sends downlink data to the terminal device through a data bearer. Therefore, for scenario 2, before the access network device sends downlink data to the terminal device, the access network device needs to establish a data bearer between the access network device and the terminal device based on the bearer configuration parameters. Therefore, the access network device needs to obtain the context of the terminal device.
  • the context of the terminal device that the access network device needs to obtain may include the entire content of the context of the terminal device, and may also include at least the AS security context and / or bearer configuration parameters. If the context of the terminal device does not include bearer configuration parameters, the access network device may use the default bearer configuration parameters to establish a data bearer between the access network device and the terminal device.
  • the access network device when the first identifier is an identifier allocated by a core network control plane network element, the access network device sends a fifth message to the core network control plane network element, the fifth message includes the first identifier, and the fifth message is used for Request the context of the end device.
  • the access network device receives a sixth message from the core network control plane network element, and the sixth message includes the context of the terminal device.
  • the sixth message further includes NCC.
  • the access network device may obtain the context of the terminal device from other access network devices. For example, when the first identifier is resume ID, if the base station that last communicated with the UE is the same as the base station that currently receives the first message, the base station that currently receives the first message saves the context of the UE. Is different from the base station that currently receives the first message, the base station that currently receives the first message obtains the context of the UE from the base station that last communicated with the UE. For example, the base station that currently receives the first message sends a ninth message to the base station that last communicated with the UE, and the ninth message includes the context request message of the UE. Then, the base station that currently receives the first message receives the tenth message from the base station that last communicated with the UE, and the tenth message includes the context of the UE.
  • the access network device After the access network device obtains the context of the terminal device, the access network device generates an AS security key based on the AS security context, and / or establishes a data bearer between the access network device and the terminal device based on the bearer configuration parameters. Then, the access network device encrypts the downlink data based on the AS security key to obtain the encrypted data.
  • the sixth message further includes an NCC
  • the access network device generates an AS security key based on the AS security context and the NCC.
  • the access network device sends a random access response message to the terminal device, the encrypted downlink data is sent through the data bearer.
  • the terminal device before the terminal device receives downlink data from the access network device, the terminal device establishes a data bearer between the access network device and the terminal device based on the saved bearer configuration parameters. After the terminal device receives the downlink data from the access network device, the terminal device parses the downlink data based on the AS security key, where the AS security key is generated by the terminal device based on the saved AS security context. Optionally, if the second message further includes NCC, the AS security key is generated by the terminal device based on the saved AS security context and the NCC.
  • the second message further includes uplink resource indication information
  • the uplink resource indication information is used to instruct the terminal device to send a response message to the access network device whether the terminal device successfully received the downlink data response message. Therefore, after the terminal device receives the downlink data from the access network device, if the terminal device parses the downlink data successfully, the terminal device uses the time-frequency resource indicated by the uplink resource instruction information to send a downlink data reception success response message to the access network device. Optionally, after the terminal device sends a downlink data reception success response message to the network device, the terminal device may enter an idle state.
  • the terminal device uses the time-frequency resource indicated by the uplink resource instruction information to send a downlink data reception failure response message to the access network device.
  • the above-mentioned two types of response messages may be the response of the physical layer whether the class is correctly received or the response of the application layer, depending on the size of the uplink resource allocated by the access network device.
  • the access network device may also allocate a dedicated preamble to the terminal device to respond to whether the terminal device successfully receives downlink data. If the terminal device initiates random access using a dedicated preamble allocated by the access network device, it indicates that the terminal device successfully received downlink data.
  • the terminal device After the terminal device receives the downlink data, if the terminal device needs to send the uplink data, it can adopt but not limited to the following design to perform ULEDT after receiving the downlink data:
  • the terminal device may send a downlink data reception success response message and uplink data to the access network device on the time-frequency resource indicated by the uplink resource indication information.
  • the uplink data here may be a single uplink data. package.
  • the access network device can also send an eleventh message to the terminal device.
  • the eleventh message is used to release the terminal device to an idle state or to establish / restore the connection of the terminal device to the connected state.
  • the eleventh message may also carry downlink data.
  • the downlink data here may be a single downlink data packet.
  • the terminal device after the terminal device receives the downlink data, the early data transmission of the uplink data can be further realized, and when the eleventh message is used to release the terminal device to an idle state, the power consumption of the terminal device can be reduced .
  • the eleventh message when the eleventh message also carries downlink data, it can better meet the transmission requirements of downlink data.
  • the terminal device may send a downlink data reception success response message and a UL EDT request message to the access network device on the time-frequency resource indicated by the uplink resource indication information, and the UL EDT request message is used to request access Network access equipment allocates uplink resources for UL EDT for terminal equipment.
  • the access network device can allocate uplink resources for the terminal device to the ULEDT.
  • the terminal equipment sends uplink data to the access network equipment on the uplink resources allocated by the access network equipment for UL EDT.
  • the access network device can also send an eleventh message to the terminal device.
  • the eleventh message is used to release the terminal device to an idle state or to establish / restore the connection of the terminal device. To connected state.
  • the eleventh message may also carry downlink data. Therefore, through the above design, after the terminal device receives the downlink data, it can request UL EDT to further transmit the data of the uplink data early. When the eleventh message is used to release the terminal device to the idle state, the terminal can be reduced. The power consumption of the device. In addition, when the eleventh message also carries downlink data, it can better meet the transmission requirements of downlink data.
  • the terminal device may use the random access resource of the ULEDT allocated by the access network device to the terminal device to send a random access message to the access network device to Instruct the access network equipment terminal equipment to initiate UL EDT.
  • the access network device determines that the terminal device uses the random access resource of the ULEDT to send the random access message, then determines that the terminal device initiates the ULEDT, and allocates the terminal device for the ULEDT.
  • Uplink resources The terminal equipment sends uplink data to the access network equipment on the uplink resources allocated by the access network equipment for UL EDT.
  • the access network device can also send an eleventh message to the terminal device.
  • the eleventh message is used to release the terminal device to an idle state or to establish / restore the connection of the terminal device. To connected state.
  • the eleventh message may also carry downlink data. Therefore, through the above design, after the terminal device receives the downlink data, it can request UL EDT to further transmit the data of the uplink data early. When the eleventh message is used to release the terminal device to the idle state, the terminal can be reduced. The power consumption of the device. In addition, when the eleventh message also carries downlink data, it can better meet the transmission requirements of downlink data.
  • the network element on the control plane of the core network obtains downlink data indication information and sends a first message to the access network device. After receiving the first message, the access network device receives the first message.
  • the second message sent to the terminal device carries downlink resource instruction information, and sends downlink data to the terminal device on the time-frequency resource indicated by the downlink resource instruction information. Therefore, by using the above method, the transmission delay of downlink data can be reduced, and early transmission of downlink data can be achieved. At the same time, the waste of resources in the EDT process triggered by DL in the prior art is avoided, and the power consumption of the terminal device can be reduced.
  • FIG. 10 is a detailed process of early transmission of CP downlink data.
  • the SGW sends a downlink data notification to the MME.
  • the downlink data notification includes downlink data.
  • the MME sends a paging message to the eNB.
  • the paging message includes downlink data and S-TMSI.
  • the message includes single downlink data indication information, where the single downlink data packet indication information is generated by the MME according to the downlink data.
  • the eNB sends a paging message to the UE.
  • the paging message includes downlink resource indication information and uplink resource indication information.
  • the uplink resource indication information may be a UL grant, and the resource indicated by the UL grant is used by the UE to perform uplink feedback on whether the downlink data is successfully received.
  • the eNB sends a NAS PDU to the UE on the time-frequency resource indicated by the downlink resource indication information, where the NAS PDU includes downlink data.
  • the NAS PDU is scrambled using P-RNTI or scrambled using RNTI allocated by eNB.
  • the UE After the UE receives the NAS PDU from the eNB, if the UE successfully parses the NAS PDU, the UE sends a downlink data reception success response message on the resource indicated by the UL grant. If the resource indicated by the UL grant is sufficiently large, the UE may also send the S-TMSI of the UE on the resource indicated by the UL grant. Optionally, after the UE sends a downlink data reception success response message to the eNB, the UE may enter an idle state to achieve a better power saving effect.
  • the UE sends a downlink data reception failure response message to the eNB on the resource indicated by the UL grant.
  • the eNB after the eNB sends a paging message to the UE, the eNB directly sends downlink data to the UE, which can reduce the transmission delay of the downlink data, realize early data transmission of the downlink data, and avoid the DL trigger in the prior art
  • the waste of resources in the EDT process can reduce the power consumption of terminal equipment and achieve better power saving effects.
  • FIG. 11 is a specific flow of early transmission of UP downlink data.
  • the SGW sends a downlink data notification to the MME.
  • the downlink data notification includes downlink data and / or single downlink data packet indication information.
  • the MME sends a paging message to the eNB.
  • the paging message includes an S-TMSI and a first identifier, where the first identifier is a resume ID or a S1 AP ID.
  • the paging message includes single downlink data packet indication information.
  • the paging message sent by the MME to the eNB may also include downlink data.
  • the eNB sends an S1 message to the MME.
  • the S1 message is used to request downlink data from the MME.
  • S1104 If the MME does not obtain downlink data in S1101, the MME sends a bearer modification request message to the SGW, where the bearer modification request message includes routing information of the eNB and is used to instruct the SGW to send downlink data to the eNB.
  • the SGW may send a bearer modification response message to the MME. This step is not shown in FIG. 11.
  • the SGW sends downlink data to the eNB.
  • S1106 If the first identifier is S1 AP ID, the eNB sends an S1 message to the MME.
  • the S1 message is used to request the context of the UE from the MME, and the S1 message includes the S1 AP ID.
  • S1103 and S1106 can be combined into one step, that is, the S1 message is used to request downlink data from the MME and also to request the context of the UE from the MME.
  • the current eNB saves the context of the UE and does not need to obtain the context of the UE from other network elements. If the eNB communicating with the UE last time is different from the current eNB, the current eNB obtains the context of the UE from the eNB communicating with the UE last time, which is omitted here and not shown in FIG. 10. Exemplarily, the current eNB sends an X2 message to the eNB that last communicated with the UE, which includes a context request message of the UE. The current eNB receives an X2 message from the eNB that last communicated with the UE, which includes the context of the UE.
  • the MME sends the context of the UE to the eNB.
  • the context of the UE includes at least the AS security context and bearer configuration parameters.
  • the MME when the MME sends the context of the UE to the eNB, it may also send NCC synchronously.
  • S1108 The eNB generates an AS security key based on the AS security context, and establishes a data bearer between the eNB and the UE based on the bearer configuration parameters.
  • the eNB generates an AS security key based on the AS security context and the NCC.
  • the eNB sends a paging message to the UE.
  • the paging message includes downlink resource indication information and uplink resource indication information.
  • the paging message may further include NCC.
  • the eNB sends downlink data to the UE on the time-frequency resources indicated by the downlink resource indication information. At this time, the eNB sends downlink data through the data bearer.
  • the UE After the UE receives downlink data from the eNB, if the UE successfully parses the downlink data according to the AS security key, the UE sends a downlink data reception success response message to the eNB on the resource indicated by the UL grant. If the resource indicated by the UL grant is sufficiently large, the UE may also send the S-TMSI of the UE on the resource indicated by the UL grant. Optionally, after the UE sends a downlink data reception success response message to the eNB, the UE may enter an idle state to achieve a better power saving effect.
  • the UE sends a downlink data reception failure response message to the eNB on the resource indicated by the UL grant.
  • the UE generates an AS security key based on the AS security context, and establishes a data bearer between the eNB and the UE based on the bearer configuration parameters.
  • the paging message sent by the eNB to the UE further includes an NCC
  • the UE generates an AS security key based on the AS security context and the NCC.
  • each step in the method flow shown in FIG. 11 may have other execution orders.
  • the eNB first obtains the context of the UE from the MME, and then obtains the downlink data from the MME.
  • the eNB adjust the execution order of certain steps or combine and execute certain steps should not be considered to be beyond the scope of this application.
  • the eNB after the eNB sends a paging message to the UE, the eNB obtains the context of the UE and establishes a data bearer with the UE, and directly sends downlink data to the UE through the data bearer, which can reduce the transmission delay of the downlink data and achieve downlink
  • the data is transmitted early, and at the same time, the waste of resources in the EDT process triggered by DL in the prior art is avoided, and the power consumption of the terminal device can be reduced to achieve a better power saving effect.
  • each network element and device for example, the foregoing access network device, terminal device, and core network control plane network element, includes a hardware structure and / or software module corresponding to each function.
  • this application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a certain function is performed by hardware or computer software-driven hardware depends on the specific application of the technical solution and design constraints. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.
  • an embodiment of the present application provides a data transmission apparatus, as shown in FIG. 12, which can be used to perform operations of an access network device.
  • the apparatus 1200 includes:
  • the receiving unit 1201 is configured to receive a first message, where the first message includes an identifier of a terminal device;
  • the sending unit 1202 is configured to send a second message to the terminal device indicated by the identifier of the terminal device, where the second message includes PRACH resource indication information corresponding to the terminal device;
  • the receiving unit 1201 is further configured to receive a random access message from the terminal device;
  • a processing unit 1203, configured to determine that the terminal device sends the random access message by using a PRACH resource indicated by the PRACH resource instruction information;
  • the sending unit is configured to send downlink data to the terminal device.
  • the first message includes downlink data indication information and / or the downlink data
  • the sending unit 1202 is further configured to send a third message to the core network control plane network element, where the third message includes the Identification, the third message is used to request the downlink data; the receiving unit 1201 is further configured to receive a fourth message from the core network control plane network element, where the fourth message includes the downlink data.
  • the identifier of the terminal device is S-TMSI
  • the first message or the fourth message includes a NAS PDU
  • the NAS PDU includes the downlink data
  • the sending unit 1202 is configured to send a random access response message to the terminal device, where the random access response message carries the downlink data.
  • the receiving unit 1201 is further configured to: before sending the downlink data indicated by the downlink data indication information to the terminal device, receive the downlink data from a user plane network element of the core network.
  • the sending unit 1202 is configured to synchronously send a random access response message and the downlink data to the terminal device.
  • the random access response message includes uplink resource indication information, and the uplink resource indication information is used to instruct the terminal device to send to the device whether the terminal device successfully receives the downlink data. Time-frequency resources used by the response message.
  • the identifier of the terminal device is an S-TMSI and a first identifier
  • the first identifier includes an identifier for obtaining a context of the terminal device
  • the sending unit 1202 is further configured to send a fifth message to the core network control plane network element, where the fifth message includes the first identifier, and the fifth message is used to request a context of the terminal device;
  • the receiving unit 1201 is further configured to receive a sixth message from the core network control plane network element, where the sixth message includes a context of the terminal device; and the context of the terminal device includes an AS security context and / or Bearer configuration parameters;
  • the processing unit 1203 is configured to generate an AS security key based on the AS security context; and / or,
  • the processing unit 1203 is configured to establish a data bearer between the apparatus and the terminal device based on the bearer configuration parameter.
  • the sixth message further includes NCC
  • the processing unit 1203 is configured to generate an AS security key based on the AS security context and the NCC.
  • the processing unit 1203 is further configured to: encrypt the downlink data based on the AS security key to obtain encrypted data;
  • the sending unit 1202 is configured to: when sending a random access response message to the terminal device, send the encrypted data through the data bearer.
  • the downlink data indication information is single downlink data packet indication information.
  • processing unit 1203, the sending unit 1202, and the receiving unit 1201 in the data transmission device may also implement other operations or functions of the access network device in the foregoing method, which are not described herein again.
  • the data transmission apparatus shown in FIG. 12 may also be used to perform operations of a terminal device.
  • the device 1200 includes:
  • the receiving unit 1201 is configured to receive a second message from an access network device, where the second message includes PRACH resource indication information corresponding to the apparatus;
  • a sending unit 1202 configured to send a random access message to the access network device by using the PRACH resource indicated by the PRACH resource instruction information;
  • the receiving unit 1201 is configured to receive downlink data from the access network device.
  • the receiving unit 1201 is configured to receive a random access response message from the access network device, the random access response message carries a NAS PDU, and the NAS PDU includes the downlink data .
  • it also includes:
  • a processing unit 1203 is configured to: before the receiving unit receives downlink data from the access network device, establish a data bearer between the access network device and the device based on the saved bearer configuration parameter;
  • the receiving unit 1201 is configured to synchronously receive a random access response message and the downlink data from the access network device, and the downlink data is carried by the data bearer.
  • the processing unit 1203 is configured to generate an AS security key based on the saved AS security context; and parse the downlink data based on the AS security key.
  • the random access response message further carries NCC
  • the processing unit 1203 is configured to generate an AS security key based on the saved AS security context and the NCC; and parse the downlink data based on the AS security key.
  • the random access response message carries uplink resource indication information
  • the uplink resource indication information is used to instruct the device to send to the access network device whether the device successfully receives the downlink Time-frequency resources used by the data response message
  • the sending unit is further configured to: after the receiving unit 1201 receives downlink data from the access network device, if the processing unit 1203 successfully parses the downlink data, use the uplink resource indication information indicated by the uplink resource indication information.
  • the time-frequency resource sends a downlink data reception success response message to the access network device;
  • the processing unit 1203 fails to parse the downlink data or the receiving unit 1201 does not receive the downlink data, the time-frequency resource indicated by the uplink resource indication information is used to send downlink data reception to the access network device. Failure response message.
  • processing unit 1203, the sending unit 1202, and the receiving unit 1201 in the data transmission device may also implement other operations or functions of the terminal device in the foregoing method, and details are not described herein again.
  • the data transmission device shown in FIG. 12 may be further configured to perform an operation of a core network control plane network element.
  • the device 1200 includes:
  • a processing unit 1203, configured to obtain downlink data indication information
  • the sending unit 1202 is configured to send a first message to the access network device, where the first message includes an identifier of the terminal device.
  • the receiving unit 1201 is configured to receive downlink data from a core network user plane network element, and the processing unit 1203 is configured to generate downlink data indication information;
  • the receiving unit 1201 is configured to receive downlink data indication information from a user plane network element of the core network.
  • the downlink data indication information is single downlink data packet indication information.
  • the first message includes the downlink data indication information and / or the downlink data indicated by the downlink data indication information;
  • the receiving unit 1201 is configured to receive a third message from the access network device, the third message includes an identifier of the terminal device, and the third message is used to request the downlink data indication information indication Downlink data;
  • the sending unit 1202 is configured to send a fourth message to the access network device, where the fourth message includes the downlink data.
  • the identifier of the terminal device is S-TMSI
  • the first message or the fourth message includes a NAS PDU
  • the NAS PDU includes the downlink data
  • the receiving unit 1201 is configured to receive a third message from the access network device, and the third message Including the identifier of the terminal device, the third message is used to request the downlink data indicated by the downlink data indication information; and the sending unit 1202 is used to send a seventh message to the user plane network element of the core network, Seven messages are used to instruct the core network user plane network element to send the eighth message to the access network device, where the eighth message includes the downlink data.
  • the identifier of the terminal device includes an S-TMSI and a first identifier
  • the first identifier includes an identifier for obtaining a context of the terminal device
  • the receiving unit 1201 is configured to receive a fifth message from the access network device, where the fifth message includes the first identifier, so The fifth message is used to request the context of the terminal device; the sending unit is used to send a sixth message to the access network device, the sixth message includes the context of the terminal device, and the terminal device
  • the context includes the AS security context and / or bearer configuration parameters.
  • the sixth message further includes an NCC.
  • processing unit 1203, the sending unit 1202, and the receiving unit 1201 in the data transmission device may also implement other operations or functions of the core network control plane network element in the foregoing method, which are not described herein again.
  • an embodiment of the present application provides a data transmission device.
  • the data transmission device may be a chip.
  • the device includes a processor and an interface.
  • the interface may be an input / output interface.
  • the processor performs the functions of the processing unit 1203, and the interface performs the functions of the receiving unit 1201 and the sending unit 1202.
  • the apparatus may further include a memory, where the memory is configured to store a program that can be run on a processor, and the processor implements the method of any one of the foregoing method embodiments when the program is executed.
  • the processor may be implemented by hardware or software. When implemented by hardware, the processor may be a logic circuit, an integrated circuit, etc .; when implemented by software, the processor may be a general-purpose processor. It is implemented by reading software code stored in a memory, which can be integrated in a processor, can be located outside the processor, and exists independently.
  • the device 1300 includes a transceiver 1301, a processor 1302, and a memory 1303.
  • the processor may be a central processing unit (CPU), a network processor (NP), a hardware chip, or any combination thereof.
  • the memory may include volatile memory, such as random access memory (RAM), and may also include non-volatile memory, such as read-only memory, ROM), flash memory (flash memory), hard disk (HDD) or solid-state drive (SSD).
  • RAM random access memory
  • non-volatile memory such as read-only memory, ROM), flash memory (flash memory), hard disk (HDD) or solid-state drive (SSD).
  • the memory may also include a combination of the above types of memories.
  • the memory 1303 is used to store a computer program; the processor 1302 calls the computer program stored in the memory 1303 and executes the method performed by the access network device in the foregoing embodiment through the transceiver 1301.
  • the memory 1303 is used to store a computer program; the processor 1302 calls the computer program stored in the memory 1303, and executes the method performed by the terminal device in the foregoing embodiment through the transceiver 1301.
  • the memory 1303 is used to store a computer program; the processor 1302 calls the computer program stored in the memory 1303 and executes the method performed by the core network control plane network element in the foregoing embodiment through the transceiver 1301.
  • the device in the embodiment shown in FIG. 13 may be implemented by the device 1200 shown in FIG. 12.
  • the processing unit 1203 may be implemented by the processor 1302, and the receiving unit 1201 and the sending unit 1202 may be implemented by the transceiver 1301.
  • An embodiment of the present application further provides a computer-readable storage medium.
  • the computer-readable storage medium stores a computer program, and when the computer program runs on a computer, the computer causes the computer to execute the method shown in any one of the foregoing method embodiments.
  • the embodiment of the present application further provides a computer program product, and when the computer program product is executed by a computer, the method shown in any one of the foregoing method embodiments is implemented.
  • the access network device receives the first message from the core network control plane network element, and the first message includes the identity of the terminal device; the access network device sends the second message to the terminal device indicated by the identity of the terminal device, and the second The message includes PRACH resource indication information corresponding to the terminal device; the access network device receives a random access message from the terminal device; the access network device determines that the terminal device sends a random access message to the terminal device using the PRACH resource indicated by the PRACH resource instruction information Send downlink data. Therefore, through the above method, the transmission delay of downlink data can be reduced, the data of the downlink data can be transmitted early, and the power consumption of the terminal device can be reduced, while avoiding the problem of wasting resources.
  • the embodiments of the present application may be provided as a method, a system, or a computer program product. Therefore, the embodiments of the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the embodiments of the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.
  • computer-usable storage media including, but not limited to, disk storage, CD-ROM, optical storage, etc.
  • Embodiments of the present application are described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or block in the flowcharts and / or block diagrams, and combinations of processes and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions.
  • These computer program instructions may be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing device to produce a machine, so that the instructions generated by the processor of the computer or other programmable data processing device are used to generate Means for implementing the functions specified in one or more flowcharts and / or one or more blocks of the block diagrams.
  • These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to work in a particular manner such that the instructions stored in the computer-readable memory produce a manufactured article including an instruction device, the instructions
  • the device implements the functions specified in one or more flowcharts and / or one or more blocks of the block diagram.
  • These computer program instructions can also be loaded on a computer or other programmable data processing device, so that a series of steps can be performed on the computer or other programmable device to produce a computer-implemented process, which can be executed on the computer or other programmable device.
  • the instructions provide steps for implementing the functions specified in one or more flowcharts and / or one or more blocks of the block diagrams.

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Abstract

一种数据传输方法及装置，该方法包括：接入网设备从核心网控制面网元接收第一消息，第一消息包括终端设备的标识；接入网设备向终端设备的标识指示的终端设备发送第二消息，第二消息包括与终端设备对应的PRACH资源指示信息；接入网设备从终端设备接收随机接入消息；接入网设备确定终端设备采用PRACH资源指示信息指示的PRACH资源发送随机接入消息，向终端设备发送下行数据。因此，通过上述方法，可以减少下行数据的传输时延，实现下行数据的数据早传，且能够降低终端设备的功耗，同时避免了资源浪费的问题。

Description

一种数据传输方法及装置 技术领域
本申请涉及无线通信领域，尤其涉及一种数据传输方法及装置。
背景技术
窄带物联网(narrow band–internet of things，NB-IoT)和机器类型通信(machine type communication，MTC)持续针对物联网的小数据包传输进行优化，设计在随机接入过程中采用数据传输的新技术，以节约小数据包的传输时延和功耗。这种在随机接入过程中进行的数据传输称为数据早传(early data transmission,EDT)。
如图1所示，现有的随机接入过程包括消息1(message 1，MSG1)到消息4(message 4，MSG4)。在传统流程(legacy procedure)中，第一个上行数据传输发生在消息5(message 5，MSG5)传输时刻，第一个下行数据传输发生MSG5之后。
在现有的EDT流程中，为了在MSG3实现上行(uplink，UL)触发的EDT，基站在消息2(message 2，MSG2)中会分配一个较大的UL资源，即为消息3(message 3，MSG3)分配较大的UL资源，例如，该UL资源的最小值为320比特，最大值为1000比特。为了在MSG4实现下行(downlink，DL)触发的EDT，用户设备(user equipment，UE)需要把原来在MSG5中携带的控制面服务请求(CP service request)放到MSG3中进行传输。如果UE为了支持DL触发的EDT而使用为MSG3分配的较大的UL资源，则会带来MSG3的填充问题以及对于UL资源的浪费，进一步使得UE由于多发送数据而带来功耗增加。例如，携带CP service request的MSG3的大小超过88比特，但是还是远小于为MSG3分配的最小的消息大小，320比特。
发明内容
本申请实施例提供一种数据传输方法及装置，用以解决DL触发的EDT过程中的资源浪费和终端设备功耗较大的问题。
第一方面，本申请实施例提供一种数据传输方法，该方法包括：
接入网设备从核心网控制面网元接收第一消息，所述第一消息包括终端设备的标识；所述接入网设备向所述终端设备的标识指示的终端设备发送第二消息，所述第二消息包括与所述终端设备对应的物理随机接入信道PRACH资源指示信息；所述接入网设备从所述终端设备接收随机接入消息；所述接入网设备确定所述终端设备采用所述PRACH资源指示信息指示的PRACH资源发送所述随机接入消息，向所述终端设备发送下行数据。
因此，通过上述方法，可以减少下行数据的传输时延，实现下行数据的数据早传，同时避免了现有技术中DL触发的EDT过程中的资源浪费，且能够降低终端设备的功耗。
在一种可能的设计中，所述第一消息包括下行数据指示信息和/或所述下行数据；或者，在所述接入网设备向所述终端设备发送下行数据之前，还包括：所述接入网设备向所述核心网控制面网元发送第三消息，所述第三消息包括所述终端设备的标识，所述第三消息用于请求所述下行数据；所述接入网设备从所述核心网控制面网元接收第四消息，所述第四 消息包括所述下行数据。
因此，接入网设备可以通过多种方式获得下行数据。
在一种可能的设计中，所述终端设备的标识为临时移动用户识别码S-TMSI，所述第一消息或者所述第四消息包括非接入层协议数据单元NAS PDU，所述NAS PDU包括所述下行数据。
因此，下行数据可以通过NAS PDU携带。
在一种可能的设计中，所述接入网设备向所述终端设备发送下行数据，包括：所述接入网设备向所述终端设备发送随机接入响应消息，所述随机接入响应消息携带所述下行数据。
因此，通过随机接入响应消息可以实现下行数据的数据早传，进一步减少下行数据的传输时延。
在一种可能的设计中，在所述接入网设备向所述终端设备发送下行数据之前，还包括：所述接入网设备从核心网用户面网元接收所述下行数据。
因此，下行数据可以由核心网用户面网元发送给接入网设备。
在一种可能的设计中，所述接入网设备向所述终端设备发送下行数据，包括：所述接入网设备向所述终端设备同步发送随机接入响应消息和所述下行数据。
因此，通过随机接入响应消息和下行数据同步发送，可以实现下行数据的数据早传，进一步减少下行数据的传输时延。
在一种可能的设计中，所述随机接入响应消息包括上行资源指示信息，所述上行资源指示信息用于指示所述终端设备向所述接入网设备发送所述终端设备是否成功接收所述下行数据的响应消息所采用的时频资源。
因此，终端设备可以针对下行数据是否成功接收在分配的上行资源上进行反馈。
在一种可能的设计中，所述终端设备的标识为S-TMSI和第一标识，所述第一标识包括用于获取所述终端设备的上下文的标识；在所述接入网设备向所述终端设备发送下行数据之前，还包括：所述接入网设备向所述核心网控制面网元发送第五消息，所述第五消息包括所述第一标识，所述第五消息用于请求所述终端设备的上下文；所述接入网设备从所述核心网控制面网元接收第六消息，所述第六消息包括所述终端设备的上下文；所述终端设备的上下文包括接入层AS安全上下文和/或承载配置参数；所述接入网设备基于所述AS安全上下文生成AS安全密钥，和/或所述接入网设备基于所述承载配置参数建立所述接入网设备与所述终端设备的数据承载。
因此，当下行数据通过数据承载携带时，接入网设备可以从核心网控制面网元获取终端设备的上下文，生成AS安全密钥，并建立数据承载。
在一种可能的设计中，所述第六消息还包括下一跳链路计数器NCC；所述接入网设备基于所述AS安全上下文生成AS安全密钥，包括：所述接入网设备基于所述AS安全上下文和所述NCC生成AS安全密钥。
因此，AS安全密钥还可通过AS安全上下文和NCC共同生成。
在一种可能的设计中，还包括:所述接入网设备基于所述AS安全密钥对所述下行数据进行加密，获得加密后的数据；所述接入网设备向所述终端设备同步发送随机接入响应消息和所述下行数据，包括：所述接入网设备在向所述终端设备发送随机接入响应消息时，通过所述数据承载发送所述加密后的数据。
因此，接入网设备基于AS安全密钥对下行数据进行加密，将加密后的数据通过建立好的数据承载与随机接入响应消息同步发送至终端设备。
在一种可能的设计中，所述下行数据指示信息为单个下行数据包指示信息。
因此，下行数据指示信息为单个下行数据包指示信息可以有效节约小数据包的传输时延和功耗。
第二方面，本申请实施例提供一种数据传输方法，该方法包括：
终端设备从接入网设备接收第二消息，所述第二消息包括与所述终端设备对应的PRACH资源指示信息；所述终端设备采用所述PRACH资源指示信息指示的PRACH资源向所述接入网设备发送随机接入消息；所述终端设备从所述接入网设备接收下行数据。
因此，通过上述方法，可以减少下行数据的传输时延，实现下行数据的数据早传，同时避免了现有技术中DL触发的EDT过程中的资源浪费，且能够降低终端设备的功耗。
在一种可能的设计中所述终端设备从所述接入网设备接收下行数据，包括：所述终端设备从所述接入网设备接收随机接入响应消息，所述随机接入响应消息携带NAS PDU，所述NAS PDU包括所述下行数据。
因此，当下行数据可以通过NAS PDU携带时，通过随机接入响应消息可以实现下行数据的数据早传，进一步减少下行数据的传输时延。
在一种可能的设计中，在所述终端设备从所述接入网设备接收下行数据之前，还包括:所述终端设备基于保存的承载配置参数建立所述接入网设备与所述终端设备的数据承载；所述终端设备从所述接入网设备接收下行数据，包括：所述终端设备从所述接入网设备同步接收随机接入响应消息和所述下行数据，所述下行数据通过所述数据承载携带。
因此，当下行数据通过数据承载携带时，通过随机接入响应消息和下行数据同步发送可以实现下行数据的数据早传，进一步减少下行数据的传输时延。
在一种可能的设计中，还包括:
所述终端设备基于保存的AS安全上下文生成AS安全密钥；所述终端设备基于所述AS安全密钥解析所述下行数据。
在一种可能的设计中，所述随机接入响应消息还携带NCC；所述方法，还包括：所述终端设备基于保存的AS安全上下文和所述NCC生成AS安全密钥；
所述终端设备基于所述AS安全密钥解析所述下行数据。
因此，终端设备可以基于不同方式生成AS安全密钥。
在一种可能的设计中，所述随机接入响应消息携带上行资源指示信息，所述上行资源指示信息用于指示所述终端设备向所述接入网设备发送所述终端设备是否成功接收所述下行数据的响应消息所采用的时频资源；在所述终端设备从所述接入网设备接收下行数据之后，还包括：若所述终端设备对所述下行数据解析成功，所述终端设备采用所述上行资源指示信息指示的时频资源向所述接入网设备发送下行数据接收成功响应消息；若所述终端设备对所述下行数据解析失败或者所述终端设备没有接收到所述下行数据，所述终端设备采用所述上行资源指示信息指示的时频资源向所述接入网设备发送下行数据接收失败响应消息。
因此，终端设备可以针对下行数据是否成功接收在分配的上行资源上进行反馈。
第三方面，本申请实施例提供一种数据传输方法，该方法包括：核心网控制面网元获取下行数据指示信息；所述核心网控制面网元向接入网设备发送第一消息，所述第一消息 包括终端设备的标识。
因此，通过上述方法，可以减少下行数据的传输时延，实现下行数据的数据早传，同时避免了现有技术中DL触发的EDT过程中的资源浪费，且能够降低终端设备的功耗。
在一种可能的设计中，核心网控制面网元获取下行数据指示信息，包括：所述核心网控制面网元从核心网用户面网元接收下行数据，生成下行数据指示信息；或者，所述核心网控制面网元从核心网用户面网元接收下行数据指示信息。
因此，核心网控制面网元可以通过不同方式获取下行数据指示信息。
在一种可能的设计中，所述下行数据指示信息为单个下行数据包指示信息。
因此，下行数据指示信息为单个下行数据包指示信息可以有效节约小数据包的传输时延和功耗。
在一种可能的设计中，所述第一消息包括下行数据指示信息和/或所述下行数据指示信息指示的下行数据；或者，所述核心网控制面网元从所述接入网设备接收第三消息，所述第三消息包括所述终端设备的标识，所述第三消息用于请求所述下行数据指示信息指示的下行数据；所述核心网控制面网元向所述接入网设备发送第四消息，所述第四消息包括所述下行数据。
因此，核心网控制面网元可以通过多种方式将下行数据发送至接入网设备。
在一种可能的设计中，所述终端设备的标识为S-TMSI，所述第一消息或者所述第四消息包括NAS PDU，所述NAS PDU包括所述下行数据。
因此，下行数据可以通过NAS PDU携带。
在一种可能的设计中，在所述核心网控制面网元向接入网设备发送第一消息之后，还包括：所述核心网控制面网元从所述接入网设备接收第三消息，所述第三消息包括所述终端设备的标识，所述第三消息用于请求所述下行数据指示信息指示的下行数据；所述核心网控制面网元向核心网用户面网元发送第七消息，所述第七消息用于指示核心网用户面网元向所述接入网设备发送所述第八消息，所述第八消息包括所述下行数据。
因此，下行数据可以由核心网用户面网元发送给接入网设备。
在一种可能的设计中，所述终端设备的标识包括S-TMSI和第一标识，所述第一标识包括用于获取所述终端设备的上下文的标识；在所述核心网控制面网元向接入网设备发送第一消息之后，还包括：所述核心网控制面网元从所述接入网设备接收第五消息，所述第五消息包括所述第一标识，所述第五消息用于请求所述终端设备的上下文；所述核心网控制面网元向所述接入网设备发送第六消息，所述第六消息包括所述终端设备的上下文，所述终端设备的上下文包括AS安全上下文和/或承载配置参数。
因此，终端设备的上下文以由核心网控制面网元发送给接入网设备。
在一种可能的设计中，所述第六消息还包括NCC。
第四方面，本申请实施例提供一种数据传输方法，该方法包括：接入网设备从核心网控制面网元接收第一消息，所述第一消息包括终端设备的标识；所述接入网设备向所述终端设备的标识指示的终端设备发送第二消息，所述第二消息包括下行资源指示信息；所述接入网设备在所述下行资源指示信息指示的时频资源上向所述终端设备发送下行数据。
因此，通过上述方法，可以减少下行数据的传输时延，实现下行数据的数据早传，同时避免了现有技术中DL触发的EDT过程中的资源浪费，且能够降低终端设备的功耗。
在一种可能的设计中，所述第二消息还包括上行资源指示信息，所述上行资源指示信 息用于指示所述终端设备向所述接入网设备发送所述终端设备是否成功接收所述下行数据的响应消息所采用的时频资源。
因此，终端设备可以针对下行数据是否成功接收在分配的上行资源上进行反馈。
在一种可能的设计中，所述第一消息包括下行数据包指示信息和/或所述下行数据。
在一种可能的设计中，所述终端设备的标识为S-TMSI，所述第一消息包括NAS PDU，所述NAS PDU包括所述下行数据。
因此，下行数据可以通过NAS PDU携带。
在一种可能的设计中，在所述接入网设备在所述下行资源指示信息指示的时频资源上向所述终端设备发送下行数据之前，还包括：所述接入网设备从核心网用户面网元接收所述下行数据。
因此，下行数据可以由核心网用户面网元发送给接入网设备。
在一种可能的设计中，所述终端设备的标识包括S-TMSI和第一标识，所述第一标识包括用于获取所述终端设备的上下文的标识；在所述接入网设备在所述下行资源指示信息指示的时频资源上向所述终端设备发送下行数据之前，还包括：所述接入网设备向所述核心网控制面网元发送第五消息，所述第五消息包括所述第一标识，所述第五消息用于请求所述终端设备的上下文；所述接入网设备从所述核心网控制面网元接收第六消息，所述第六消息包括所述终端设备的上下文；所述终端设备的上下文包括AS安全上下文和/或承载配置参数；所述接入网设备基于所述AS安全上下文生成AS安全密钥，和/或所述接入网设备基于所述承载配置参数建立所述接入网设备与所述终端设备的数据承载。
因此，当下行数据通过数据承载携带时，接入网设备可以从核心网控制面网元获取终端设备的上下文，生成AS安全密钥，并建立数据承载。
在一种可能的设计中，所述第六消息还包括NCC；所述接入网设备基于所述AS安全上下文生成AS安全密钥，包括：所述接入网设备基于所述AS安全上下文和所述NCC生成AS安全密钥。
因此，AS安全密钥还可通过AS安全上下文和NCC共同生成。
在一种可能的设计中，还包括：所述接入网设备基于所述生成的AS安全密钥对所述下行数据进行加密，获得加密后的数据；所述接入网设备在所述下行资源指示信息指示的时频资源上向所述终端设备发送下行数据，包括：所述接入网设备在所述下行资源指示信息指示的时频资源上通过所述数据承载向所述终端设备发送所述加密后的数据。
因此，接入网设备基于AS安全密钥对下行数据进行加密，将加密后的数据通过建立好的数据承载在所述下行资源指示信息指示的时频资源上发送给终端设备。
在一种可能的设计中，所述下行数据指示信息为单个下行数据包指示信息。
第五方面，本申请实施例提供一种数据传输方法，该方法包括：终端设备从接入网设备接收第二消息，所述第二消息包括下行资源指示信息；所述终端设备在所述下行资源指示信息指示的时频资源上从所述接入网设备接收下行数据。
因此，通过上述方法，可以减少下行数据的传输时延，实现下行数据的数据早传，同时避免了现有技术中DL触发的EDT过程中的资源浪费，且能够降低终端设备的功耗。
在一种可能的设计中，所述第二消息还包括上行资源指示信息，所述上行资源指示信息用于指示所述终端设备向所述接入网设备发送所述终端设备是否成功接收所述下行数据的响应消息所采用的时频资源；在所述终端设备在所述下行资源指示信息指示的时频资 源上从所述接入网设备接收下行数据之后，还包括：若所述终端设备对所述下行数据解析成功，所述终端设备采用所述上行资源指示信息指示的时频资源向所述接入网设备发送下行数据接收成功响应消息；若所述终端设备对所述下行数据解析失败或者所述终端设备没有接收到所述下行数据，所述终端设备采用所述上行资源指示信息指示的时频资源向所述接入网设备发送下行数据接收失败响应消息。
因此，终端设备可以针对下行数据是否成功接收在分配的上行资源上进行反馈。
在一种可能的设计中，所述终端设备在所述下行资源指示信息指示的时频资源上从所述接入网设备接收下行数据，包括：所述终端设备在所述下行资源指示信息指示的时频资源上从所述接入网设备接收NAS PDU，所述NAS PDU包括所述下行数据。
因此，下行数据可以通过NAS PDU携带。
在一种可能的设计中，在所述终端设备在所述下行资源指示信息指示的时频资源上从所述接入网设备接收下行数据之前，还包括：所述终端设备基于保存的承载配置参数建立所述接入网设备与所述终端设备的数据承载；所述终端设备在所述下行资源指示信息指示的时频资源上从所述接入网设备接收下行数据，包括：所述终端设备在所述下行资源指示信息指示的时频资源上从所述接入网设备接收下行数据，所述下行数据通过所述数据承载携带。
因此，下行数据可以通过数据承载携带。
在一种可能的设计中，还包括：所述终端设备基于保存的AS安全上下文生成AS安全密钥；所述终端设备基于所述AS安全密钥解析所述下行数据。
在一种可能的设计中，所述第二消息还携带NCC；所述方法，还包括：所述终端设备基于保存的AS安全上下文和所述NCC生成AS安全密钥；所述终端设备基于所述AS安全密钥解析所述下行数据。
因此，终端设备可以基于不同方式生成AS安全密钥。
第六方面，提供了一种装置。本申请提供的装置具有实现上述方法方面中接入网设备或终端设备或核心网控制面网元行为的功能，其包括用于执行上述方法方面所描述的步骤或功能相对应的部件(means)。所述步骤或功能可以通过软件实现，或硬件(如电路)实现，或者通过硬件和软件结合来实现。
在一种可能的设计中，上述装置包括一个或多个处理器和通信单元。所述一个或多个处理器被配置为支持所述装置执行上述方法中终端设备相应的功能。所述通信单元用于支持所述装置与其他设备通信，实现接收和/或发送功能。
可选的，所述装置还可以包括一个或多个存储器，所述存储器用于与处理器耦合，其保存装置必要的程序指令和/或数据。所述一个或多个存储器可以和处理器集成在一起，也可以与处理器分离设置。本申请并不限定。
所述装置可以为物联网终端设备等，所述通信单元可以是收发器，或收发电路。可选的，所述收发器也可以为输入/输出电路或者接口。
所述装置还可以为通信芯片。所述通信单元可以为通信芯片的输入/输出电路或者接口。
另一个可能的设计中，上述装置，包括收发器、处理器和存储器。该处理器用于控制收发器或输入/输出电路收发信号，该存储器用于存储计算机程序，该处理器用于运行该存储器中的计算机程序，使得该装置执行第二方面或第二方面中任一种可能实现方式中终端设备完成的方法，或者使得该装置执行第五方面或第五方面中任一种可能实现方式中终端 设备完成的方法。
在一种可能的设计中，上述装置包括一个或多个处理器和通信单元。所述一个或多个处理器被配置为支持所述装置执行上述方法中接入网设备相应的功能。所述通信单元用于支持所述装置与其他设备通信，实现接收和/或发送功能。
可选的，所述装置还可以包括一个或多个存储器，所述存储器用于与处理器耦合，其保存接入网设备必要的程序指令和/或数据。所述一个或多个存储器可以和处理器集成在一起，也可以与处理器分离设置。本申请并不限定。
所述装置可以为eNB或gNB等，所述通信单元可以是收发器，或收发电路。可选的，所述收发器也可以为输入/输出电路或者接口。
所述装置还可以为通信芯片。所述通信单元可以为通信芯片的输入/输出电路或者接口。
另一个可能的设计中，上述装置，包括收发器、处理器和存储器。该处理器用于控制收发器或输入/输出电路收发信号，该存储器用于存储计算机程序，该处理器用于运行存储器中的计算机程序，使得该装置执行第一方面或第一方面中任一种可能实现方式中接入网设备完成的方法，或者使得该装置执行第四方面或第四方面中任一种可能实现方式中接入网设备完成的方法。
在一种可能的设计中，上述装置包括一个或多个处理器和通信单元。所述一个或多个处理器被配置为支持所述装置执行上述方法中核心网控制面网元相应的功能。所述通信单元用于支持所述装置与其他设备通信，实现接收和/或发送功能。
可选的，所述装置还可以包括一个或多个存储器，所述存储器用于与处理器耦合，其保存核心网控制面网元必要的程序指令和/或数据。所述一个或多个存储器可以和处理器集成在一起，也可以与处理器分离设置。本申请并不限定。
所述装置可以为MME或AMF等，所述通信单元可以是收发器，或收发电路。可选的，所述收发器也可以为输入/输出电路或者接口。
所述装置还可以为通信芯片。所述通信单元可以为通信芯片的输入/输出电路或者接口。
另一个可能的设计中，上述装置，包括收发器、处理器和存储器。该处理器用于控制收发器或输入/输出电路收发信号，该存储器用于存储计算机程序，该处理器用于运行存储器中的计算机程序，使得该装置执行第三方面或第三方面中任一种可能实现方式中核心网控制面网元完成的方法。
第七方面，提供了一种系统，该系统包括上述终端设备、接入网设备和核心网控制面网元。
第八方面，提供了一种计算机可读存储介质，用于存储计算机程序，该计算机程序包括用于执行第一方面或第一方面中任一种可能实现方式中的方法的指令，或用于执行第二方面或第二方面中任一种可能实现方式中的方法的指令，或用于执行第三方面或第三方面中任一种可能实现方式中的方法的指令，或用于执行第四方面或第四方面中任一种可能实现方式中的方法的指令，或用于执行第五方面或第五方面中任一种可能实现方式中的方法的指令。
第九方面，提供了一种计算机程序产品，所述计算机程序产品包括：计算机程序代码，当所述计算机程序代码在计算机上运行时，使得计算机执行上述第一方面或第一方面中任一种可能实现方式中的方法，或使得计算机执行上述第二方面或第二方面中任一种可能实现方式中的方法，或使得计算机执行上述第三方面或第三方面中任一种可能实现方式中的 方法，或使得计算机执行上述第四方面或第四方面中任一种可能实现方式中的方法，或使得计算机执行上述第五方面或第五方面中任一种可能实现方式中的方法。
附图说明
图1为本申请中现有的随机接入过程的示意图；
图2为本申请中4G系统的系统架构示意图；
图3为本申请中5G系统的系统架构示意图；
图4为本申请中物联网业务场景的示意图；
图5为本申请中现有的DL触发的EDT的具体流程图；
图6为本申请中数据传输方法的概述流程图之一；
图7为本申请中CP下行数据数据早传的具体流程图之一；
图8为本申请中UP下行数据数据早传的具体流程图之一；
图9为本申请中数据传输方法的概述流程图之二；
图10为本申请中CP下行数据数据早传的具体流程图之二；
图11为本申请中UP下行数据数据早传的具体流程图之二；
图12为本申请中数据传输装置的结构示意图之一；
图13为本申请中数据传输装置的结构示意图之二。
具体实施方式
下面结合附图，对本申请的实施例进行描述。
首先介绍本申请实施例适用的系统架构。图2为本申请实施例适用的一种具体系统架构示意图。如图2所示，4G系统的系统架构包括无线接入网和核心网两部分，其中，无线接入网为演进的通用陆地无线接入网(evolved universal terrestrial radio access network，E-UTRAN)，用于实现无线接入有关的功能。核心网包括移动性管理实体(mobility management entity，MME)、服务网关(serving gateway，SGW)、分组数据网络网关(packet data network gateway，PGW)等。其中，MME主要负责控制面的移动性管理和会话管理。SGW是用户面功能实体，完成分组数据的路由和转发。PGW是连接外部数据网的网关。在实际的网络部署中，S-GW和P-GW可以是合一部署的，一般统称为网关。UE可以通过建立从UE到E-UTRAN到SGW到PGW到分组数据网络(packet data network，PDN)的连接来访问外部PDN。
图3为本申请实施例适用的另一种具体系统架构的示意图。如图3所示，5G系统的系统架构同样分为无线接入网和核心网两部分。无线接入网为下一代无线接入网(next generation radio access networks，NG-RAN)，用于实现无线接入有关的功能。核心网包括：接入和移动性管理功能(core access and mobility management function，AMF)网元、会话管理功能(session management function，SMF)网元、用户面功能(user plane function，UPF)网元等。其中，AMF网元主要负责移动性管理。AMF网元也可称为AMF设备或AMF实体。SMF网元主要负责会话管理。SMF网元也可称为SMF设备或SMF实体。UPF主要负责对用户报文进行处理，例如转发等。UE可以通过建立从UE到NG-RAN到UPF到数据网络(data network，DN)之间的会话来访问DN。
应理解的是，上述图2和图3所示的系统架构仅为举例，本申请实施例适用的系统架构可以不限于以上两种具体系统架构。
本申请实施例中所涉及到的接入网设备是指为终端设备提供无线接入的设备，可以包括各种形式的基站，例如：宏基站，微基站(也称为小站)，中继站，接入点、演进型基站(eNodeB)、无线保真接入点(wireless fidelity access point，WiFi AP)、全球微波接入互操作性(worldwide interoperability for microwave access base station，WiMAX BS)等。在采用不同的系统中，具备提供无线接入功能的设备的名称可能会有所不同，例如，在4G系统中，接入网设备可称为演进的节点B(evolved NodeB，eNB或者eNodeB)，在5G系统中，接入网设备可称为gNB(gNodeB)。
本申请实施例中所涉及到的终端设备主要为物联网终端设备，例如火灾检测传感器、智能水表/电表、工厂监控设备、智能家居、汽车、可穿戴设备等
本申请实施例中所涉及到的核心网控制面设备是指系统架构内核心网中的控制面功能实体。在采用不同的系统中，控制面设备的名称可能会有所不同，例如，在4G系统中，控制面设备称为MME，在5G系统中，控制面设备称为AMF。
本申请实施例中所涉及到的核心网用户面设备是指系统架构内核心网中的用户面功能实体。在采用不同的系统中，用户面设备的名称可能会有所不同，例如，在4G系统中，用户面设备称为SGW，在5G系统中，用户面设备称为UPF。
本申请实施例适用的主要业务场景为物联网的业务场景，如图4所示。物联网作为第五代移动通信(5G)的组成部分，其市场需求增长迅猛，预测显示,到2022年5G物联网的连接数将会达到180亿。目前3GPP标准已经基于蜂窝网络，针对物联网的特点提出了解决方案，比如NB-IoT网络和MTC网络。二者均利用了窄带技术的特点，来承载IoT业务。其中，NB-IoT网络应用了独立于现有蜂窝网络的新空口技术，终端设备成本较低，支持的速率和移动性较低。MTC网络属于传统蜂窝网络的一部分，终端设备成本较高，支持的速率和移动性较高。总体上，与传统蜂窝网络相比，物联网的业务和终端设备具有以下特点：
(1)物联网的业务速率低、周期长。例如，与传统蜂窝网络相比，NB-IoT业务产生的数据包更小，同时对于时延通常不是很敏感。
(2)海量连接要求。例如，对大规模部署的智能水/电表，智能家居，汽车，可穿戴设备等物联网终端设备，一个NB-IoT基站下可能存在大量上述类型的终端设备(例如，超过数万个)。
(3)终端设备低成本要求。例如，较现有蜂窝网络的终端设备，NB-IoT要求终端设备的成本较低，同时要求终端设备的实现复杂性也较低，以实现终端设备的海量部署。
(4)终端设备低功耗要求。例如，NB-IoT要求终端设备的功耗较低，从而节约终端设备电池电量，保证终端设备的超长待机时间，进而节约更换电池的人力成本。
应理解的是，本申请实施例描述的系统架构以及业务场景是为了更加清楚的说明本申请实施例的技术方案，并不构成对本申请实施例提供的技术方案的限定，本领域技术人员可知，随着系统架构的演变和新业务场景的出现，本申请实施例提供的技术方案对于类似的技术问题，同样适用。
参阅图5所示，为现有技术中DL触发的EDT的具体流程。
S501：eNB广播EDT配置信息。其中，包括为每一个覆盖等级广播的允许使用EDT的上行数据量控制门限，以及EDT物理随机接入信道(physical random access channel，PRACH)资源。
S502：UE从eNB接收寻呼消息。
S503：UE向eNB发送随机接入消息。
具体的，在UE判断该寻呼消息是针对自身后，UE根据自身覆盖等级和需要发送的上行数据量判断是否使用EDT，如果需要发送的上行数据量大于自身覆盖等级对应的上行数据量控制门限，则发起传统的随机接入流程，如果需要发送的上行数据量小于或等于自身覆盖等级对应的上行数据量控制门限，则发起EDT流程。当UE确定发起EDT流程时，UE根据eNB广播的EDT配置信息采用EDT PRACH资源发起随机接入，进而指示本次随机接入是一次EDT流程。这里需要发送的上行数据量是指MSG3的数据量。
S504：eNB向UE发送随机接入响应消息(random access response，RAR)，该RAR携带用于上行数据传输的资源指示信息，例如，上行调度授权(UL grant)。
S505：UE向eNB发送MSG3，MSG3携带NAS PDU和S-TMSI，NAS PDU包括CP service request。UE采用RAR携带的用于上行数据传输的资源指示信息指示的资源发送MSG3。
S506：eNB向UE发送MSG4，MSG4携带NAS PDU，NAS PDU包括下行数据。
具体的，在eNB接收到携带NAS PDU的MSG3后，eNB向MME发送该NAS PDU，在MME接收到该NAS PDU后，MME将下行数据通过eNB发送给UE。eNB还可让UE在接收下行数据后进入空闲(idle)态。
当采用上述流程实现DL EDT时，UE采用用于上行数据传输的资源指示信息指示的资源发送MSG3，而用于上行数据传输的资源指示信息指示的资源一般较大，因此，会带来MSG3的填充问题以及资源的浪费，进一步使得终端设备由于多发送数据而带来功耗增加。
基于上述问题，本申请实施例提供一种数据传输方法，用以解决DL触发的EDT过程中的资源浪费问题，实现降低终端设备的功耗。如图6所示，该方法包括：
步骤601：核心网控制面网元获取下行数据指示信息。
针对步骤601，核心网控制面网元可以从核心网用户面网元接收下行数据，生成下行数据指示信息；或者，核心网控制面网元直接从核心网用户面网元接收下行数据指示信息。
为了节约小数据包的传输时延和功耗，需要采用DL触发的EDT的下行数据量一般较小，因此，在一种可能的设计中，下行数据指示信息为单个下行数据包指示信息。
步骤602：核心网控制面网元向接入网设备发送第一消息。第一消息包括终端设备的标识。第一消息还可以包括下行数据指示信息。示例性地，第一消息可以为寻呼消息。终端设备的标识可以包括SAE临时移动用户识别码(SAE-temporary mobile subscriber identity，S-TMSI)，或者，终端设备的标识可以包括S-TMSI和第一标识，其中，第一标识包括用于获取终端设备的上下文的标识。在一个示例中，第一标识可以是核心网控制面网元分配的标识，例如，S1 AP ID是MME分配的标识，该标识用于从MME获取UE的上下文。在另一个示例中，第一标识可以是接入网设备分配的标识，例如，恢复标识(resume ID)是与UE上次通信的基站分配的标识，该标识是与UE上次通信的基站在向MME发送的UE上下文挂起请求(UE context suspend request)中携带给MME的，该标识可以作为S1AP  IE或者携带在无线资源控制容器(radio resource control container)中，以保证该标识不被MME解析，该标识用于从与UE上次通信的基站获取上下文。
步骤603：在接入网设备从核心网控制面网元接收第一消息后，接入网设备向终端设备的标识指示的终端设备发送第二消息。示例性地，第二消息可以为寻呼消息。第二消息包括与终端设备对应的PRACH资源指示信息。示例性地，PRACH资源是指为终端设备分配的前导码(preamble)或者为终端设备分配的随机接入使用的时频资源或者为终端分配的preabmle和随机接入使用的时频资源。例如，基站为每一个S-TMSI建立一个PRACH资源的映射信息，以使基站能够根据接收到的随机接入消息采用的PRACH资源判断是哪个UE接入网络。
步骤604：在终端设备从接入网设备接收第二消息后，终端设备采用PRACH资源指示信息指示的PRACH资源向接入网设备发送随机接入消息。
步骤605：在接入网设备从终端设备接收随机接入消息后，接入网设备确定终端设备采用PRACH资源指示信息指示的PRACH资源发送随机接入消息，向终端设备发送下行数据。
在一种可能的设计中，接入网设备采用小区无线网络临时标识(cell-radio network temporary identifier，C-RNTI)或者随机接入无线网络临时标识(RA-radio network temporary identifier，RA-RNTI)对下行数据进行加扰，获得加扰后的下行数据，接入网设备向终端设备发送加扰后的下行数据。
在接入网设备向终端设备发送下行数据之前，接入网设备可以采用但不限于以下方式获取下行数据：
方式一：第一消息包括下行数据。
此时，核心网控制面网元可以从核心网用户面网元接收下行数据，生成下行数据指示信息，并在向接入网设备发送第一消息时，将下行数据携带在第一消息中。
方式二：接入网设备从核心网控制面网元接收下行数据。
示例性地，在接入网设备向终端设备发送下行数据之前，接入网设备向核心网控制面网元发送第三消息，第三消息包括终端设备的标识，第三消息用于请求下行数据。接入网设备从核心网控制面网元接收第四消息，第四消息包括下行数据。
方式三：接入网设备从核心网用户面网元接收下行数据。
示例性地，在接入网设备向终端设备发送下行数据之前，接入网设备向核心网控制面网元发送第三消息，第三消息包括终端设备的标识，第三消息用于请求下行数据。核心网控制面网元向核心网用户面网元发送第七消息，第七消息用于指示核心网用户面网元向接入网设备发送第八消息，第八消息包括下行数据。
其中，在第一消息包括S-TMSI，不包括第一标识的场景(以下简称为场景1)下，接入网设备可以采用上述方式1或方式2获取下行数据。示例性地，第一消息或者第四消息包括非接入层协议数据单元(non-access stratum protocol data unit，NAS PDU)，NAS PDU包括下行数据。进一步地，针对步骤605，接入网设备向终端设备发送随机接入响应消息，随机接入响应消息携带下行数据。应理解的是，此时随机接入响应消息包括NAS PDU，NAS PDU包括下行数据。
在第一消息包括S-TMSI和第一标识的场景(以下简称为场景2)下，接入网设备可以采用上述方式1、方式2或方式3获取下行数据。进一步地，针对步骤605，接入网设 备向终端设备发送随机接入响应消息和下行数据。此时，接入网设备在向终端设备发送随机接入响应消息时，通过数据承载发送下行数据。因此，针对场景2，在接入网设备向终端设备发送下行数据之前，接入网设备还需基于承载配置参数建立接入网设备与终端设备的数据承载。因此，接入网设备还需获取终端设备的上下文。应理解的是，接入网设备所需获取的终端设备的上下文可以包括终端设备的上下文的全部内容，也可以至少包括接入层(access stratum，AS)安全上下文和/或承载配置参数。若终端设备的上下文不包括承载配置参数，则接入网设备可以采用默认的承载配置参数建立接入网设备与终端设备的数据承载。
在一个示例中，当第一标识为核心网控制面网元分配的标识时，接入网设备向核心网控制面网元发送第五消息，第五消息包括第一标识，第五消息用于请求终端设备的上下文。接入网设备从核心网控制面网元接收第六消息，第六消息包括终端设备的上下文。可选的，第六消息还包括下一跳链路计数器(next hop chaining counter，NCC)。
当第一标识为是接入网设备分配的标识时，接入网设备可以从其他接入网设备获取终端设备的上下文。例如，当第一标识为resume ID时，若与UE上次通信的基站与当前接收到第一消息的基站相同，则当前接收到第一消息的基站保存UE的上下文，若与UE上次通信的基站与当前接收到第一消息的基站不同，则当前接收到第一消息的基站从与UE上次通信的基站获取UE的上下文。例如，当前接收到第一消息的基站向与UE上次通信的基站发送第九消息，第九消息包括UE的上下文请求消息。然后，当前接收到第一消息的基站从与UE上次通信的基站接收第十消息，第十消息包括UE的上下文。
在接入网设备获取终端设备的上下文后，接入网设备基于AS安全上下文生成AS安全密钥，和/或基于承载配置参数建立接入网设备与终端设备的数据承载。可选的，若第六消息还包括NCC，则接入网设备基于AS安全上下文和NCC生成AS安全密钥。
然后，接入网设备基于AS安全密钥对下行数据进行加密，获得加密后的数据。最终，接入网设备在向终端设备发送随机接入响应消息时，通过数据承载发送加密后的下行数据。
相应的，针对场景2，在终端设备从接入网设备接收下行数据之前，终端设备基于保存的承载配置参数建立接入网设备与终端设备的数据承载。在终端设备从接入网设备接收到该下行数据后，终端设备基于AS安全密钥解析下行数据，其中，AS安全密钥是终端设备基于保存的AS安全上下文生成的。可选的，若随机接入响应消息还携带NCC，则AS安全密钥是终端设备基于保存的AS安全上下文和NCC生成的。
此外，针对场景1和场景2，在一种可能的设计中，随机接入响应消息包括上行资源指示信息，上行资源指示信息用于指示终端设备向接入网设备发送终端设备是否成功接收下行数据的响应消息所采用的时频资源。因此，在终端设备从接入网设备接收下行数据之后，若终端设备对下行数据解析成功，终端设备采用上行资源指示信息指示的时频资源向接入网设备发送下行数据接收成功响应消息；若终端设备对下行数据解析失败或者终端设备没有接收到下行数据，终端设备采用上行资源指示信息指示的时频资源向接入网设备发送下行数据接收失败响应消息。应理解的是，上述两种响应消息可以是物理层的是否正确接收类的响应，也可以是应用层的响应，取决于接入网设备分配的上行资源的大小。
此外，在终端设备接收到下行数据后，若终端设备有上行数据需要发送，可在接收到下行数据后采用但不限于以下设计进行UL EDT：
在一种可能的设计中，终端设备可以在上行资源指示信息指示的时频资源上向接入网 设备发送下行数据接收成功响应消息和上行数据，例如，这里的上行数据可以为单个上行数据包。在接入网设备接收到上行数据后，接入网设还可以向终端设备发送第十一消息，第十一消息用于将终端设备释放到空闲态或者建立/恢复终端设备的连接到连接态。可选的，该第十一消息还可携带下行数据，例如，这里的下行数据可以为单个下行数据包。因此，通过上述设计，在终端设备接收到下行数据后，可以进一步实现上行数据的数据早传，且当第十一消息用于将终端设备释放到空闲态时，能够实现降低终端设备的功耗。此外，当第十一消息还携带下行数据时，能够更好地满足下行数据的传输需求。
在另一种可能的设计中，终端设备可以在上行资源指示信息指示的时频资源上向接入网设备发送下行数据接收成功响应消息和UL EDT请求消息，该UL EDT请求消息用于请求接入网设备为终端设备分配用于UL EDT的上行资源。接入网设备在接收到该UL EDT请求信息后，接入网设备可以为终端设备分配用于UL EDT的上行资源。终端设备在接入网设备分配的用于UL EDT的上行资源上向接入网设备发送上行数据。同理，在接入网设备接收到上行数据后，接入网设还可以向终端设备发送第十一消息，第十一消息用于将终端设备释放到空闲态或者建立/恢复终端设备的连接到连接态。可选的，该第十一消息还可携带下行数据。因此，通过上述设计，在终端设备接收到下行数据后，可以请求UL EDT，进而实现上行数据的数据早传，且当第十一消息用于将终端设备释放到空闲态时，能够实现降低终端设备的功耗。此外，当第十一消息还携带下行数据时，能够更好地满足下行数据的传输需求。
综上，采用如图6所示实施例提供的方法，核心网控制面网元获取下行数据指示信息，并向接入网设备发送第一消息，接入网设备在接收到第一消息后，向终端设备发送的第二消息携带为终端设备分配的PRACH资源的指示信息，当接入网设备确定终端设备采用PRACH资源指示信息指示的PRACH资源发送随机接入消息，向终端设备发送下行数据。因此，通过上述方法，可以减少下行数据的传输时延，实现下行数据的数据早传，同时避免了现有技术中DL触发的EDT过程中的资源浪费，且能够降低终端设备的功耗。
基于如图6所示的实施例，下面针对控制面(control plane，CP)下行数据数据早传流程和用户面(user plane，UP)下行数据数据早传分别进行介绍。应理解的是，图7和图8的举例具体应用于4G的系统架构，本申请实施例还可应用于其他系统架构，本申请对此不作限定。
参阅图7所示，为CP下行数据数据早传的具体流程。
S701：SGW向MME发送下行数据通知(Downlink data notification)。该下行数据通知包括下行数据和/或单个下行数据包指示信息。
S702：MME向eNB发送寻呼消息。该寻呼消息包括S-TMSI。可选的，该寻呼消息中包括单个下行数据包指示信息。
可选的，若下行数据通知包括下行数据，则MME向eNB发送的寻呼消息还可以包括下行数据，此时，该寻呼消息包括NAS PDU，NAS PDU包括下行数据。因此，S706和S707为可选的步骤，当MME向eNB发送的寻呼消息包括下行数据时，S706和S707无需执行。
S703：eNB向UE发送寻呼消息。该寻呼消息包括与该S-TMSI对应的PRACH资源指示信息。
示例性地，eNB为每一个S-TMSI分配对应的PRACH资源，即为每一个S-TMSI建立一个PRACH资源的映射信息，以便eNB基于接收到的随机接入消息采用的PRACH资源来判断具体哪个UE接入网络。其中，PRACH资源可以为码，比如preamble，和/或时频资源等。
S704：UE基于eNB发送的寻呼消息中PRACH资源指示信息指示的PRACH资源向eNB发送随机接入消息。
S705：eNB从UE接收随机接入消息，确定UE采用PRACH资源指示信息指示的PRACH资源发送随机接入消息，进而确定发起随机接入的UE，即eNB确定UE为成功接收寻呼消息的UE。
S706：eNB向MME发送S1消息，该S1消息用于向MME请求下行数据PDU。
示例性地，这里的S1消息可以为UE初始消息(UE initial message)，其中包括UE的标识。eNB将其中的NAS PDU的长度设置为0，其他信元(information element，IE)可以正常设置。这里的S1消息也可以为新的S1消息，其中包括UE的标识，新的S1消息用于请求该标识对应的UE所需的下行数据。
S707：MME向eNB发送S1下行消息，该消息可以是连接建立指示信息，或者下行NAS传输消息，其中包括NAS PDU，该NAS PDU中包括下行数据。
示例性地，若MME在S701没有获取到下行数据，则MME在收到eNB在S706发送的S1消息后，从SGW接收下行数据。此时，若MME和SGW之间没有用户面路径，则MME向SGW发送承载修改请求消息来建立用户面路径，并在用户面路径建立成功后从SGW接收下行数据；若MME和SGW之间的用户面路径已经建立完成，则MME可直接从SGW接收下行数据。
应理解的是，S706和S707是当MME向eNB发送的寻呼消息不包括下行数据时才需执行的操作。其中，S706和S707可以在S705之后执行，即在eNB确定UE发起随机接入之后，eNB再向MME请求下行数据。或者，S706和S707可以在S704之前或在S704之后且在接收到随机接入消息之前执行，即eNB先向MME请求下行数据，然后eNB确定UE发起随机接入，本申请对此不作限定。
S708：eNB向UE发送随机接入响应消息，该随机接入响应消息包括NAS PDU和UL grant，该NAS PDU中包括下行数据，其中，NAS PDU是使用C-RNTI进行加扰的或者使用RA-RNTI进行加扰的。UL grant指示的资源用于UE对是否成功接收该NAS PDU进行上行反馈。可选的，NAS PDU也可以和随机接入响应消息复用在一个传输块中传输。
S709：在UE从eNB接收到随机接入响应消息后，若UE成功解析随机接入响应消息中的NAS PDU，则UE在UL grant指示的资源上向eNB发送下行数据接收成功响应消息。如果UL grant指示的资源足够大，UE还可以在UL grant指示的资源上发送该UE的S-TMSI。
此外，若UE对下行数据解析失败或者UE没有接收到下行数据，UE在UL grant指示的资源上向eNB发送下行数据接收失败响应消息，该种情况未在图7中画出。
因此，相较于现有技术，通过MSG4实现下行数据的数据早传，采用如图7所示实施例提供的方法，通过MSG2(即随机接入响应消息)发送NAS PDU可以实现下行数据的数据早传，可以进一步减少下行数据的传输时延，同时避免了现有技术中DL触发的EDT过程中的资源浪费，且能够降低终端设备的功耗。
参阅图8所示，为UP下行数据数据早传的具体流程。
S801：SGW向MME发送下行数据通知。该下行数据通知包括下行数据和/或单个下行数据包指示信息。
S802：MME向eNB发送寻呼消息。该寻呼消息包括S-TMSI和第一标识，其中，该第一标识为resume ID或S1 AP ID。可选的，该寻呼消息中包括单个下行数据包指示信息。
可选的，若下行数据通知包括下行数据，则MME向eNB发送的寻呼消息中也可以包括下行数据。
S803：eNB向UE发送寻呼消息。该寻呼消息包括与该S-TMSI对应的PRACH资源指示信息。
S804：UE基于eNB发送的寻呼消息中PRACH资源指示信息指示的PRACH资源向eNB发送随机接入消息。
S805：eNB从UE接收随机接入消息，确定UE采用PRACH资源指示信息指示的PRACH资源发送随机接入消息，进而确定发起随机接入的UE，即eNB确定UE为成功接收寻呼消息的UE。
S806：eNB向MME发送S1消息，该S1消息用于向MME请求下行数据。该S1消息可以是新的S1消息，比如下行数据请求消息。或者该S1消息可以使用其他现有的上行S1消息。
S807a：若MME在S801获取到下行数据，MME向eNB发送下行数据。示例性地，MME向eNB发送S1下行消息，其中包括下行数据。
S807b1:若MME在S801没有获取到下行数据，MME向SGW发送修改承载请求消息，其中，该修改承载请求消息包括eNB的路由信息，用于指示SGW向eNB发送下行数据。
进一步地，SGW还可以在接收到修改承载请求消息后，向MME发送承载修改响应消息，该步骤未在图8中画出。
S807b2：SGW向eNB发送下行数据。
应理解的是，上述S807a与S807b1和S807b2为两种不同的方案。针对S806、S807a、S807b1、S807b2，S808的执行次序，在一种示例中，S806、S807a和S808依次执行，在另一种示例中，S806、S807b1、S807b2，S808依次执行。此外，若MME向eNB发送的寻呼消息包括下行数据，则S806、S807a或S806、S807b1、S807b2均无需执行。
S808：若第一标识为S1 AP ID，eNB向MME发送S1消息，该S1消息用于向MME请求UE的上下文，该S1消息包括S1 AP ID。
可选的，若第一标识为S1 AP ID，S806和S808可以合并为一个步骤，即S1消息既用于向MME请求下行数据，同时也用于向MME请求UE的上下文。
此外，若第一标识为resume ID，若与UE上次通信的eNB与当前eNB相同，则当前eNB保存UE的上下文，不需要从其他网元获取UE的上下文。若与UE上次通信的eNB与当前eNB不同，则当前eNB从与UE上次通信的eNB获取UE的上下文，此处省略未在图8中画出。示例性地，当前eNB向与UE上次通信的eNB发送X2消息，其中包括UE的上下文请求消息。当前eNB从与UE上次通信的eNB接收X2消息，其中包括UE的上下文。
S809：MME向eNB发送UE的上下文。UE的上下文至少包括AS安全上下文和承载 配置参数。
可选的，MME在向eNB发送UE的上下文时，还可同步发送NCC。
S810：eNB基于AS安全上下文生成AS安全密钥，基于承载配置参数建立eNB与UE的数据承载。
可选的，若MME向eNB发送了NCC，则eNB基于AS安全上下文和NCC生成AS安全密钥。
S811：eNB向UE发送随机接入响应消息和下行数据。此时，eNB通过数据承载发送下行数据。该随机接入响应消息可以包括UL grant，UL grant指示的资源用于UE对是否成功接收下行数据进行上行反馈。
可选的，随机接入响应消息还可以包括NCC。
S812：在UE从eNB接收到随机接入响应消息和下行数据后，若UE根据AS安全密钥成功解析下行数据，则UE在UL grant指示的资源上向eNB发送下行数据接收成功响应消息。如果UL grant指示的资源足够大，UE还可以在UL grant指示的资源上发送该UE的S-TMSI。
此外，若UE对下行数据解析失败或者UE没有接收到下行数据，UE在UL grant指示的资源上向eNB发送下行数据接收失败响应消息。
其中，UE基于AS安全上下文生成AS安全密钥，基于承载配置参数建立eNB与UE的数据承载。可选的，随机接入响应消息还可以包括NCC，则UE基于AS安全上下文和NCC生成AS安全密钥。
应理解的是，如图8所示的方法流程中的各个步骤还可以有其他的执行次序，例如，eNB先向MME获取UE的上下文，然后再向MME获取下行数据等。本领域技术人员结合上述如图8所示的方法流程，调整某些步骤的执行次序或将某些步骤合并执行不应认为超出本申请的范围。
因此，相较于现有技术，通过MSG4实现下行数据的数据早传，采用如图8所示实施例提供的方法，通过MSG2和下行数据同步发送，可以实现下行数据的数据早传，可以进一步减少下行数据的传输时延，同时避免了现有技术中DL触发的EDT过程中的资源浪费，且能够降低终端设备的功耗。
本申请实施例提供一种数据传输方法，用以解决DL触发的EDT过程中的资源浪费问题，实现降低终端设备的功耗。如图9所示，该方法包括：
步骤901：核心网控制面网元获取下行数据指示信息。
针对步骤901，核心网控制面网元可以从核心网用户面网元接收下行数据，生成下行数据指示信息；或者，核心网控制面网元直接从核心网用户面网元接收下行数据指示信息。
为了节约小数据包的传输时延和功耗，需要采用DL EDT的下行数据量一般较小，因此，在一种可能的设计中，下行数据指示信息为单个下行数据包指示信息。
步骤902：核心网控制面网元向接入网设备发送第一消息。第一消息包括终端设备的标识。可选的，第一消息包括下行数据指示信息。示例性地，第一消息可以为寻呼消息。终端设备的标识可以包括S-TMSI，或者，终端设备的标识可以包括S-TMSI和第一标识，其中，第一标识包括用于获取终端设备的上下文的标识。在一个示例中，第一标识可以是核心网控制面网元分配的标识，例如，S1 AP ID是MME分配的标识，该标识用于从MME 获取UE的上下文。在另一个示例中，第一标识可以是接入网设备分配的标识，例如，resume ID是与UE上次通信的基站分配的标识，该标识是与UE上次通信的基站在向MME发送的UE context suspend request中携带给MME的，该标识可以作为S1AP IE或者携带在RRC container中，以保证该标识不被MME解析，该标识用于从与UE上次通信的基站获取上下文。
步骤903：在接入网设备从核心网控制面网元接收第一消息后，接入网设备向终端设备的标识指示的终端设备发送第二消息。示例性地，第二消息可以为寻呼消息。第二消息包括下行资源指示信息。
步骤904：接入网设备在下行资源指示信息指示的时频资源上向终端设备发送下行数据。
在一种可能的设计中，接入网设备采用寻呼无线网络临时标识(Paging-radio network temporary identifier，P-RNTI)或者接入网设备分配的RNTI对下行数据进行加扰，获得加扰后的下行数据，接入网设备向终端设备发送加扰后的下行数据。
在接入网设备向终端设备发送下行数据之前，接入网设备可以采用但不限于以下方式获取下行数据：
方式一：第一消息包括下行数据。
此时，核心网控制面网元可以从核心网用户面网元接收下行数据，生成下行数据指示信息，并在向接入网设备发送第一消息时，将下行数据携带在第一消息中。
方式二：接入网设备从核心网用户面网元接收下行数据。
示例性地，在接入网设备向终端设备发送下行数据之前，接入网设备向核心网控制面网元发送第三消息，第三消息包括终端设备的标识，第三消息用于请求下行数据。核心网控制面网元向核心网用户面网元发送第七消息，第七消息用于指示核心网用户面网元向接入网设备发送第八消息，第八消息包括下行数据。
其中，在第一消息包括S-TMSI，不包括第一标识的场景(以下简称为场景1)下，接入网设备可以采用上述方式1获取下行数据。示例性地，第一消息包括NAS PDU，NAS PDU包括下行数据。进一步地，针对步骤904，接入网设备向终端设备发送NAS PDU，NAS PDU包括下行数据。
在第一消息包括S-TMSI和第一标识的场景(以下简称为场景2)下，接入网设备可以采用上述方式1或方式2获取下行数据。进一步地，针对步骤904，接入网设备向终端设备通过数据承载发送下行数据。因此，针对场景2，在接入网设备向终端设备发送下行数据之前，接入网设备还需基于承载配置参数建立接入网设备与终端设备的数据承载。因此，接入网设备需获取终端设备的上下文。应理解的是，接入网设备所需获取的终端设备的上下文可以包括终端设备的上下文的全部内容，也可以至少包括AS安全上下文和/或承载配置参数。若终端设备的上下文不包括承载配置参数，则接入网设备可以采用默认的承载配置参数建立接入网设备与终端设备的数据承载。
在一个示例中，当第一标识为核心网控制面网元分配的标识时，接入网设备向核心网控制面网元发送第五消息，第五消息包括第一标识，第五消息用于请求终端设备的上下文。接入网设备从核心网控制面网元接收第六消息，第六消息包括终端设备的上下文。可选的，第六消息还包括NCC。
当第一标识为是接入网设备分配的标识时，接入网设备可以从其他接入网设备获取终端设备的上下文。例如，当第一标识为resume ID时，若与UE上次通信的基站与当前接收到第一消息的基站相同，则当前接收到第一消息的基站保存UE的上下文，若与UE上次通信的基站与当前接收到第一消息的基站不同，则当前接收到第一消息的基站从与UE上次通信的基站获取UE的上下文。例如，当前接收到第一消息的基站向与UE上次通信的基站发送第九消息，第九消息包括UE的上下文请求消息。然后，当前接收到第一消息的基站从与UE上次通信的基站接收第十消息，第十消息包括UE的上下文。
在接入网设备获取终端设备的上下文后，接入网设备基于AS安全上下文生成AS安全密钥，和/或基于承载配置参数建立接入网设备与终端设备的数据承载。然后，接入网设备基于AS安全密钥对下行数据进行加密，获得加密后的数据。可选的，若第六消息还包括NCC，则接入网设备基于AS安全上下文和NCC生成AS安全密钥。最终，接入网设备在向终端设备发送随机接入响应消息时，通过数据承载发送加密后的下行数据。
相应的，针对场景2，在终端设备从接入网设备接收下行数据之前，终端设备基于保存的承载配置参数建立接入网设备与终端设备的数据承载。在终端设备从接入网设备接收到该下行数据后，终端设备基于AS安全密钥解析下行数据，其中，AS安全密钥是终端设备基于保存的AS安全上下文生成的。可选的，若第二消息还包括NCC，则AS安全密钥是终端设备基于保存的AS安全上下文和NCC生成的。
在一种可能的设计中，第二消息还包括上行资源指示信息，上行资源指示信息用于指示终端设备向接入网设备发送终端设备是否成功接收下行数据的响应消息所采用的时频资源。因此，在终端设备从接入网设备接收下行数据之后，若终端设备对下行数据解析成功，终端设备采用上行资源指示信息指示的时频资源向接入网设备发送下行数据接收成功响应消息。可选的，在终端设备向网络设备发送下行数据接收成功响应消息后，终端设备可以进入idle状态。若终端设备对下行数据解析失败或者终端设备没有接收到下行数据，终端设备采用上行资源指示信息指示的时频资源向接入网设备发送下行数据接收失败响应消息。应理解的是，上述两种响应消息可以是物理层的是否正确接收类的响应，也可以是应用层的响应，取决于接入网设备分配的上行资源的大小。此外，接入网设备还可以为终端设备分配专用的前导码(preamble)用于对终端设备是否成功接收下行数据进行响应。若终端设备采用接入网设备分配的专用的preamble发起随机接入，则表示终端设备成功接收下行数据。
此外，在终端设备接收到下行数据后，若终端设备有上行数据需要发送，可在接收到下行数据后采用但不限于以下设计进行UL EDT：
在第一种可能的设计中，终端设备可以在上行资源指示信息指示的时频资源上向接入网设备发送下行数据接收成功响应消息和上行数据，例如，这里的上行数据可以为单个上行数据包。在接入网设备接收到上行数据后，接入网设还可以向终端设备发送第十一消息，第十一消息用于将终端设备释放到空闲态或者建立/恢复终端设备的连接到连接态。可选的，该第十一消息还可携带下行数据，例如，这里的下行数据可以为单个下行数据包。因此，通过上述设计，在终端设备接收到下行数据后，可以进一步实现上行数据的数据早传，且当第十一消息用于将终端设备释放到空闲态时，能够实现降低终端设备的功耗。此外，当第十一消息还携带下行数据时，能够更好地满足下行数据的传输需求。
在第二种可能的设计中，终端设备可以在上行资源指示信息指示的时频资源上向接入 网设备发送下行数据接收成功响应消息和UL EDT请求消息，该UL EDT请求消息用于请求接入网设备为终端设备分配用于UL EDT的上行资源。接入网设备在接收到该UL EDT请求信息后，接入网设备可以为终端设备分配用于UL EDT的上行资源。终端设备在接入网设备分配的用于UL EDT的上行资源上向接入网设备发送上行数据。同理，在接入网设备接收到上行数据后，接入网设还可以向终端设备发送第十一消息，第十一消息用于将终端设备释放到空闲态或者建立/恢复终端设备的连接到连接态。可选的，该第十一消息还可携带下行数据。因此，通过上述设计，在终端设备接收到下行数据后，可以请求UL EDT，进而实现上行数据的数据早传，且当第十一消息用于将终端设备释放到空闲态时，能够实现降低终端设备的功耗。此外，当第十一消息还携带下行数据时，能够更好地满足下行数据的传输需求。
在第三种可能的设计中，在终端设备接收到下行数据后，终端设备可以采用接入网设备为终端设备分配的UL EDT的随机接入资源向接入网设备发送随机接入消息，以指示接入网设备终端设备发起UL EDT。在接入网设备接收到随机接入消息后，接入网设备确定终端设备采用UL EDT的随机接入资源发送随机接入消息，则确定终端设备发起UL EDT，为终端设备分配用于UL EDT的上行资源。终端设备在接入网设备分配的用于UL EDT的上行资源上向接入网设备发送上行数据。同理，在接入网设备接收到上行数据后，接入网设还可以向终端设备发送第十一消息，第十一消息用于将终端设备释放到空闲态或者建立/恢复终端设备的连接到连接态。可选的，该第十一消息还可携带下行数据。因此，通过上述设计，在终端设备接收到下行数据后，可以请求UL EDT，进而实现上行数据的数据早传，且当第十一消息用于将终端设备释放到空闲态时，能够实现降低终端设备的功耗。此外，当第十一消息还携带下行数据时，能够更好地满足下行数据的传输需求。
综上，采用如图9所示实施例提供的方法，核心网控制面网元获取下行数据指示信息，并向接入网设备发送第一消息，接入网设备在接收到第一消息后，向终端设备发送的第二消息携带下行资源指示信息，并在下行资源指示信息指示的时频资源上向终端设备发送下行数据。因此，通过上述方法，可以减少下行数据的传输时延，实现下行数据的数据早传，同时避免了现有技术中DL触发的EDT过程中的资源浪费，且能够降低终端设备的功耗。
基于如图9所示的实施例，下面针对CP下行数据数据早传流程和UP下行数据数据早传分别进行介绍。应理解的是，图10和图11的举例具体应用于4G的系统架构，本申请实施例还可应用于其他系统架构，本申请对此不作限定。
参阅图10所示，为CP下行数据数据早传的具体流程。
S1001：SGW向MME发送下行数据通知。该下行数据通知包括下行数据。
S1002：MME向eNB发送寻呼消息。该寻呼消息包括下行数据和S-TMSI。可选的，该消息消息中包括单个下行数据指示信息，其中，单个下行数据包指示信息是MME根据下行数据生成的。
S1003：eNB向UE发送寻呼消息。该寻呼消息包括下行资源指示信息和上行资源指示信息。
示例性地，上行资源指示信息可以为UL grant，UL grant指示的资源用于UE对是否成功接收下行数据进行上行反馈。
S1004：eNB在下行资源指示信息指示的时频资源上向UE发送NAS PDU，该NAS PDU包括下行数据。其中，该NAS PDU是使用P-RNTI进行加扰的或者使用eNB分配的RNTI进行加扰的。
S1005：在UE从eNB接收到NAS PDU后，若UE成功解析NAS PDU，则UE在UL grant指示的资源上向eNB发送下行数据接收成功响应消息。如果UL grant指示的资源足够大，UE还可以在UL grant指示的资源上发送该UE的S-TMSI。可选的，在UE向eNB发送下行数据接收成功响应消息后，UE可以进入idle状态，以达到较好的节电效果。
此外，若UE对下行数据解析失败或者UE没有接收到下行数据，UE在UL grant指示的资源上向eNB发送下行数据接收失败响应消息。
因此，通过上述方法，在eNB向UE发送寻呼消息后，eNB直接向UE发送下行数据，可以减少下行数据的传输时延，实现下行数据的数据早传，同时避免了现有技术中DL触发的EDT过程中的资源浪费，且能够降低终端设备的功耗，达到较好的节电效果。
参阅图11所示，为UP下行数据数据早传的具体流程。
S1101：SGW向MME发送下行数据通知。该下行数据通知包括下行数据和/或单个下行数据包指示信息。
S1102：MME向eNB发送寻呼消息。该寻呼消息包括S-TMSI和第一标识，其中，该第一标识为resume ID或S1 AP ID。可选的，该寻呼消息中包括单个下行数据包指示信息。
可选的，若下行数据通知包括下行数据，则MME向eNB发送的寻呼消息中也可以包括下行数据。
S1103：eNB向MME发送S1消息，该S1消息用于向MME请求下行数据。
S1104:若MME在S1101没有获取到下行数据，MME向SGW发送修改承载请求消息，其中，该修改承载请求消息包括eNB的路由信息，用于指示SGW向eNB发送下行数据。
进一步地，SGW还可以在接收到修改承载请求消息后，向MME发送承载修改响应消息，该步骤未在图11中画出。
S1105：SGW向eNB发送下行数据。
S1106：若第一标识为S1 AP ID，eNB向MME发送S1消息，该S1消息用于向MME请求UE的上下文，该S1消息包括S1 AP ID。
可选的，若第一标识为S1 AP ID，S1103和S1106可以合并为一个步骤，即S1消息既用于向MME请求下行数据，同时也用于向MME请求UE的上下文。
此外，若第一标识为resume ID，若与UE上次通信的eNB与当前eNB相同，则当前eNB保存UE的上下文，不需要从其他网元获取UE的上下文。若与UE上次通信的eNB与当前eNB不同，则当前eNB从与UE上次通信的eNB获取UE的上下文，此处省略未在图10中画出。示例性地，当前eNB向与UE上次通信的eNB发送X2消息，其中包括UE的上下文请求消息。当前eNB从与UE上次通信的eNB接收X2消息，其中包括UE的上下文。
S1107：MME向eNB发送UE的上下文。UE的上下文至少包括AS安全上下文和承载配置参数。
可选的，MME在向eNB发送UE的上下文时，还可同步发送NCC。
S1108：eNB基于AS安全上下文生成AS安全密钥，基于承载配置参数建立eNB与UE的数据承载。
可选的，若MME向eNB发送了NCC，则eNB基于AS安全上下文和NCC生成AS安全密钥。
S1109：eNB向UE发送寻呼消息。该寻呼消息包括下行资源指示信息和上行资源指示信息。可选的，该寻呼消息还可以包括NCC。
S1110：eNB在下行资源指示信息指示的时频资源上向UE发送下行数据。此时，eNB通过数据承载发送下行数据。
S1111：在UE从eNB接收到下行数据后，若UE根据AS安全密钥成功解析下行数据，则UE在UL grant指示的资源上向eNB发送下行数据接收成功响应消息。如果UL grant指示的资源足够大，UE还可以在UL grant指示的资源上发送该UE的S-TMSI。可选的，在UE向eNB发送下行数据接收成功响应消息后，UE可以进入idle状态，以达到较好的节电效果。
此外，若UE对下行数据解析失败或者UE没有接收到下行数据，UE在UL grant指示的资源上向eNB发送下行数据接收失败响应消息。
其中，UE基于AS安全上下文生成AS安全密钥，基于承载配置参数建立eNB与UE的数据承载。可选的，若eNB向UE发送寻呼消息还包括NCC，则UE基于AS安全上下文和NCC生成AS安全密钥。
应理解的是，如图11所示的方法流程中的各个步骤还可以有其他的执行次序，例如，eNB先向MME获取UE的上下文，然后再向MME获取下行数据等。本领域技术人员结合上述如图11所示的方法流程，调整某些步骤的执行次序或将某些步骤合并执行不应认为超出本申请的范围。
因此，通过上述方法，在eNB向UE发送寻呼消息后，eNB获取UE的上下文建立与UE的数据承载，并通过数据承载直接向UE发送下行数据，可以减少下行数据的传输时延，实现下行数据的数据早传，同时避免了现有技术中DL触发的EDT过程中的资源浪费，且能够降低终端设备的功耗，达到较好的节电效果。
上述本申请提供的实施例中，分别从各个网元本身、以及从各个网元之间交互的角度对本申请实施例提供的通信方法的各方案进行了介绍。可以理解的是，各个网元和设备，例如上述接入网设备、终端设备和核心网控制面网元为了实现上述功能，其包含了执行各个功能相应的硬件结构和/或软件模块。本领域技术人员应该很容易意识到，结合本文中所公开的实施例描述的各示例的单元及算法步骤，本申请能够以硬件或硬件和计算机软件的结合形式来实现。某个功能究竟以硬件还是计算机软件驱动硬件的方式来执行，取决于技术方案的特定应用和设计约束条件。专业技术人员可以对每个特定的应用来使用不同方法来实现所描述的功能，但是这种实现不应认为超出本申请的范围。
在一个实施例中，本申请实施例提供一种数据传输装置，如图12所示，可用于执行接入网设备的操作，该装置1200包括：
接收单元1201，用于接收第一消息，所述第一消息包括终端设备的标识；
发送单元1202，用于向所述终端设备的标识指示的终端设备发送第二消息，所述第二 消息包括与所述终端设备对应的PRACH资源指示信息；
所述接收单元1201，还用于从所述终端设备接收随机接入消息；
处理单元1203，用于确定所述终端设备采用所述PRACH资源指示信息指示的PRACH资源发送所述随机接入消息；
所述发送单元，用于向所述终端设备发送下行数据。
在一种可能的设计中，所述第一消息包括下行数据指示信息和/或所述下行数据；
在所述发送单元1202向所述终端设备发送下行数据之前，所述发送单元1202，还用于向所述核心网控制面网元发送第三消息，所述第三消息包括所述终端设备的标识，所述第三消息用于请求所述下行数据；所述接收单元1201，还用于从所述核心网控制面网元接收第四消息，所述第四消息包括所述下行数据。
在一种可能的设计中，所述终端设备的标识为S-TMSI，所述第一消息或者所述第四消息包括NAS PDU，所述NAS PDU包括所述下行数据。
在一种可能的设计中，所述发送单元1202，用于向所述终端设备发送随机接入响应消息，所述随机接入响应消息携带所述下行数据。
在一种可能的设计中，所述接收单元1201，还用于：在向所述终端设备发送所述下行数据指示信息指示的下行数据之前，从核心网用户面网元接收所述下行数据。
在一种可能的设计中，所述发送单元1202，用于所述向所述终端设备同步发送随机接入响应消息和所述下行数据。
在一种可能的设计中，所述随机接入响应消息包括上行资源指示信息，所述上行资源指示信息用于指示所述终端设备向所述装置发送所述终端设备是否成功接收所述下行数据的响应消息所采用的时频资源。
在一种可能的设计中，所述终端设备的标识为S-TMSI和第一标识，所述第一标识包括用于获取所述终端设备的上下文的标识；
在向所述终端设备发送所述下行数据指示信息指示的下行数据之前，
所述发送单元1202，还用于向所述核心网控制面网元发送第五消息，所述第五消息包括所述第一标识，所述第五消息用于请求所述终端设备的上下文；
所述接收单元1201，还用于：从所述核心网控制面网元接收第六消息，所述第六消息包括所述终端设备的上下文；所述终端设备的上下文包括AS安全上下文和/或承载配置参数；
所述处理单元1203，用于基于所述AS安全上下文生成AS安全密钥；和/或，
所述处理单元1203，用于基于所述承载配置参数建立所述装置与所述终端设备的数据承载。
在一种可能的设计中，所述第六消息还包括NCC；
所述处理单元1203，用于基于所述AS安全上下文和所述NCC生成AS安全密钥。
在一种可能的设计中，所述处理单元1203，还用于：基于所述AS安全密钥对所述下行数据进行加密，获得加密后的数据；
所述发送单元1202，用于：在向所述终端设备发送随机接入响应消息时，通过所述数据承载发送所述加密后的数据。
在一种可能的设计中，所述下行数据指示信息为单个下行数据包指示信息。
此外，数据传输装置中的处理单元1203、发送单元1202和接收单元1201还可实现上 述方法中接入网设备的其他操作或功能，此处不再赘述。
在另一个实施例中，图12所示的数据传输装置还可用于执行终端设备的操作。如图12所示，该装置1200包括：
接收单元1201，用于从接入网设备接收第二消息，所述第二消息包括与所述装置对应的PRACH资源指示信息；
发送单元1202，用于采用所述PRACH资源指示信息指示的PRACH资源向所述接入网设备发送随机接入消息；
所述接收单元1201，用于从所述接入网设备接收下行数据。
在一种可能的设计中，所述接收单元1201，用于从所述接入网设备接收随机接入响应消息，所述随机接入响应消息携带NAS PDU，所述NAS PDU包括所述下行数据。
在一种可能的设计中，还包括:
处理单元1203，用于：在所述接收单元从所述接入网设备接收下行数据之前，基于保存的承载配置参数建立所述接入网设备与所述装置的数据承载；
所述接收单元1201，用于从所述接入网设备同步接收随机接入响应消息和所述下行数据，所述下行数据通过所述数据承载携带。
在一种可能的设计中，处理单元1203，用于基于保存的AS安全上下文生成AS安全密钥；基于所述AS安全密钥解析所述下行数据。
在一种可能的设计中，所述随机接入响应消息还携带NCC；
所述处理单元1203，用于基于保存的AS安全上下文和所述NCC生成AS安全密钥；基于所述AS安全密钥解析所述下行数据。
在一种可能的设计中，所述随机接入响应消息携带上行资源指示信息，所述上行资源指示信息用于指示所述装置向所述接入网设备发送所述装置是否成功接收所述下行数据的响应消息所采用的时频资源；
所述发送单元，还用于：在所述接收单元1201从所述接入网设备接收下行数据之后，若所述处理单元1203对所述下行数据解析成功，采用所述上行资源指示信息指示的时频资源向所述接入网设备发送下行数据接收成功响应消息；
若所述处理单元1203对所述下行数据解析失败或者所述接收单元1201没有接收到所述下行数据，采用所述上行资源指示信息指示的时频资源向所述接入网设备发送下行数据接收失败响应消息。
此外，数据传输装置中的处理单元1203、发送单元1202和接收单元1201还可实现上述方法中终端设备的其他操作或功能，此处不再赘述。
在另一个实施例中，图12所示的数据传输装置还可用于执行核心网控制面网元的操作。如图12所示，该装置1200包括：
处理单元1203，用于获取下行数据指示信息；
发送单元1202，用于向接入网设备发送第一消息，所述第一消息包括终端设备的标识。
在一种可能的设计中，接收单元1201，用于从核心网用户面网元接收下行数据，所述处理单元1203，用于生成下行数据指示信息；
或者，接收单元1201，用于从核心网用户面网元接收下行数据指示信息。
在一种可能的设计中，所述下行数据指示信息为单个下行数据包指示信息。
在一种可能的设计中，所述第一消息包括所述下行数据指示信息和/或所述下行数据指 示信息指示的下行数据；
或者，所述接收单元1201，用于从所述接入网设备接收第三消息，所述第三消息包括所述终端设备的标识，所述第三消息用于请求所述下行数据指示信息指示的下行数据；
所述发送单元1202，用于向所述接入网设备发送第四消息，所述第四消息包括所述下行数据。
在一种可能的设计中，所述终端设备的标识为S-TMSI，所述第一消息或者所述第四消息包括NAS PDU，所述NAS PDU包括所述下行数据。
在一种可能的设计中，在所述发送单元1202向接入网设备发送第一消息之后，所述接收单元1201，用于从所述接入网设备接收第三消息，所述第三消息包括所述终端设备的标识，所述第三消息用于请求所述下行数据指示信息指示的下行数据；所述发送单元1202，用于向核心网用户面网元发送第七消息，所述第七消息用于指示核心网用户面网元向所述接入网设备发送所述第八消息，所述第八消息包括所述下行数据。
在一种可能的设计中，所述终端设备的标识包括S-TMSI和第一标识，所述第一标识包括用于获取所述终端设备的上下文的标识；
在所述发送单元1202向接入网设备发送第一消息之后，所述接收单元1201，用于从所述接入网设备接收第五消息，所述第五消息包括所述第一标识，所述第五消息用于请求所述终端设备的上下文；所述发送单元，用于向所述接入网设备发送第六消息，所述第六消息包括所述终端设备的上下文，所述终端设备的上下文包括AS安全上下文和/或承载配置参数。
在一种可能的设计中，所述第六消息还包括NCC。
此外，数据传输装置中的处理单元1203、发送单元1202和接收单元1201还可实现上述方法中核心网控制面网元的其他操作或功能，此处不再赘述。
作为另一种可选的变形，本申请实施例提供一种数据传输装置，示例性地，可以为一种芯片，该装置包括处理器和接口，该接口可以为输入/输出接口。其中，处理器完成上述处理单元1203的功能，接口完成上述接收单元1201和发送单元1202的功能。该装置还可以包括存储器，存储器用于存储可在处理器上运行的程序，处理器执行该程序时实现上述任一方法实施例的方法。该处理器可以通过硬件来实现也可以通过软件来实现，当通过硬件实现时，该处理器可以是逻辑电路、集成电路等；当通过软件来实现时，该处理器可以是一个通用处理器，通过读取存储器中存储的软件代码来实现，该存储器可以集成在处理器中，可以位于所述处理器之外，独立存在。
基于以上实施例，本申请实施例还提供了一种数据传输装置，参阅图13所示，该装置1300中包括：收发器1301、处理器1302、存储器1303。其中，处理器可以是中央处理器(Central Processing Unit，CPU)，网络处理器(network processor，NP)，硬件芯片或者其任意组合。存储器可以包括易失性存储器(volatile memory)，例如随机存取存储器(random access memory，RAM)，也可以包括非易失性存储器(non-volatile memory)，例如只读存储器(read-only memory，ROM)，快闪存储器(flash memory)，硬盘(hard disk drive，HDD)或固态硬盘(solid-state drive，SSD)，存储器还可以包括上述种类的存储器的组合。
当该装置为接入网设备时，存储器1303用于存储计算机程序；处理器1302调用存储器1303存储的计算机程序，通过收发器1301执行上述实施例中接入网设备执行的方法。
当该装置为终端设备时，存储器1303用于存储计算机程序；处理器1302调用存储器1303存储的计算机程序，通过收发器1301执行上述实施例中终端设备执行的方法。
当该装置为核心网控制面网元时，存储器1303用于存储计算机程序；处理器1302调用存储器1303存储的计算机程序，通过收发器1301执行上述实施例中核心网控制面网元执行的方法。
可以理解的，上述图13所示实施例中的装置可以以图12所示的装置1200实现。具体的，处理单元1203可以由处理器1302实现，接收单元1201和发送单元1202可以由收发器1301实现。
本申请实施例还提供一种计算机可读存储介质，该计算机可读存储介质存储有计算机程序，当该计算机程序在计算机上运行时，使得计算机执行上述任一方法实施例所示的方法。
本申请实施例还提供了一种计算机程序产品，该计算机程序产品被计算机执行时实现上述任一方法实施例所示的方法。
综上所述，接入网设备从核心网控制面网元接收第一消息，第一消息包括终端设备的标识；接入网设备向终端设备的标识指示的终端设备发送第二消息，第二消息包括与终端设备对应的PRACH资源指示信息；接入网设备从终端设备接收随机接入消息；接入网设备确定终端设备采用PRACH资源指示信息指示的PRACH资源发送随机接入消息，向终端设备发送下行数据。因此，通过上述方法，可以减少下行数据的传输时延，实现下行数据的数据早传，且能够降低终端设备的功耗，同时避免了资源浪费的问题。
另外，本文中术语“系统”和“网络”在本文中常被可互换使用。本文中术语“和/或”，仅仅是一种描述关联对象的关联关系，表示可以存在三种关系，例如，A和/或B，可以表示：单独存在A，同时存在A和B，单独存在B这三种情况。另外，本文中字符“/”，一般表示前后关联对象是一种“或”的关系。应理解，在本申请实施例中，“与A相应的B”表示B与A相关联，根据A可以确定B。但还应理解，根据A确定B并不意味着仅仅根据A确定B，还可以根据A和/或其它信息确定B。
本领域内的技术人员应明白，本申请实施例可提供为方法、系统、或计算机程序产品。因此，本申请实施例可采用完全硬件实施例、完全软件实施例、或结合软件和硬件方面的实施例的形式。而且，本申请实施例可采用在一个或多个其中包含有计算机可用程序代码的计算机可用存储介质(包括但不限于磁盘存储器、CD-ROM、光学存储器等)上实施的计算机程序产品的形式。
本申请实施例是参照根据本申请实施例的方法、设备(系统)、和计算机程序产品的流程图和/或方框图来描述的。应理解可由计算机程序指令实现流程图和/或方框图中的每一流程和/或方框、以及流程图和/或方框图中的流程和/或方框的结合。可提供这些计算机程序指令到通用计算机、专用计算机、嵌入式处理机或其他可编程数据处理设备的处理器以产生一个机器，使得通过计算机或其他可编程数据处理设备的处理器执行的指令产生用于实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能的装置。
这些计算机程序指令也可存储在能引导计算机或其他可编程数据处理设备以特定方式工作的计算机可读存储器中，使得存储在该计算机可读存储器中的指令产生包括指令装置的制造品，该指令装置实现在流程图一个流程或多个流程和/或方框图一个方框或多个 方框中指定的功能。
这些计算机程序指令也可装载到计算机或其他可编程数据处理设备上，使得在计算机或其他可编程设备上执行一系列操作步骤以产生计算机实现的处理，从而在计算机或其他可编程设备上执行的指令提供用于实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能的步骤。
显然，本领域的技术人员可以对本申请实施例进行各种改动和变型而不脱离本申请的精神和范围。这样，倘若本申请实施例的这些修改和变型属于本申请权利要求及其等同技术的范围之内，则本申请也意图包含这些改动和变型在内。

Claims (28)

  1. 一种数据传输方法，其特征在于，该方法包括：
    接入网设备从核心网控制面网元接收第一消息，所述第一消息包括终端设备的标识；
    所述接入网设备向所述终端设备的标识指示的终端设备发送第二消息，所述第二消息包括与所述终端设备对应的物理随机接入信道PRACH资源指示信息；
    所述接入网设备从所述终端设备接收随机接入消息；
    所述接入网设备确定所述终端设备采用所述PRACH资源指示信息指示的PRACH资源发送所述随机接入消息，向所述终端设备发送下行数据。
  2. 如权利要求1所述的方法，其特征在于，所述第一消息包括下行数据指示信息和/或所述下行数据；或者，
    在所述接入网设备向所述终端设备发送所述下行数据之前，还包括：
    所述接入网设备向所述核心网控制面网元发送第三消息，所述第三消息包括所述终端设备的标识，所述第三消息用于请求所述下行数据；
    所述接入网设备从所述核心网控制面网元接收第四消息，所述第四消息包括所述下行数据。
  3. 如权利要求2所述的方法，其特征在于，所述终端设备的标识为临时移动用户识别码S-TMSI，所述第一消息或者所述第四消息包括非接入层协议数据单元NAS PDU，所述NAS PDU包括所述下行数据。
  4. 如权利要求1-3任一项所述的方法，其特征在于，所述接入网设备向所述终端设备发送下行数据，包括：
    所述接入网设备向所述终端设备发送随机接入响应消息，所述随机接入响应消息携带所述下行数据。
  5. 如权利要求1所述的方法，其特征在于，在所述接入网设备向所述终端设备发送下行数据之前，还包括：
    所述接入网设备从核心网用户面网元接收所述下行数据。
  6. 如权利要求1、2、5任一项所述的方法，其特征在于，所述接入网设备向所述终端设备发送下行数据，包括：
    所述接入网设备向所述终端设备同步发送随机接入响应消息和所述下行数据。
  7. 如权利要求6所述的方法，其特征在于，所述随机接入响应消息包括上行资源指示信息，所述上行资源指示信息用于指示所述终端设备向所述接入网设备发送所述终端设备是否成功接收所述下行数据的响应消息所采用的时频资源。
  8. 如权利要求6或7所述的方法，其特征在于，所述终端设备的标识为S-TMSI和第一标识，所述第一标识包括用于获取所述终端设备的上下文的标识；
    在所述接入网设备向所述终端设备发送下行数据之前，还包括：
    所述接入网设备向所述核心网控制面网元发送第五消息，所述第五消息包括所述第一标识，所述第五消息用于请求所述终端设备的上下文；
    所述接入网设备从所述核心网控制面网元接收第六消息，所述第六消息包括所述终端设备的上下文；所述终端设备的上下文包括接入层AS安全上下文和/或承载配置参数；
    所述接入网设备基于所述AS安全上下文生成AS安全密钥，和/或所述接入网设备基 于所述承载配置参数建立所述接入网设备与所述终端设备的数据承载。
  9. 如权利要求8所述的方法，其特征在于，所述第六消息还包括下一跳链路计数器NCC；
    所述接入网设备基于所述AS安全上下文生成AS安全密钥，包括：
    所述接入网设备基于所述AS安全上下文和所述NCC生成AS安全密钥。
  10. 如权利要求8或9所述的方法，其特征在于，还包括:
    所述接入网设备基于所述AS安全密钥对所述下行数据进行加密，获得加密后的数据；
    所述接入网设备向所述终端设备同步发送随机接入响应消息和所述下行数据，包括：
    所述接入网设备在向所述终端设备发送随机接入响应消息时，通过所述数据承载发送所述加密后的数据。
  11. 如权利要求2-10任一项所述的方法，其特征在于，所述下行数据指示信息为单个下行数据包指示信息。
  12. 一种数据传输方法，其特征在于，该方法包括：
    终端设备从接入网设备接收第二消息，所述第二消息包括与所述终端设备对应的PRACH资源指示信息；
    所述终端设备采用所述PRACH资源指示信息指示的PRACH资源向所述接入网设备发送随机接入消息；
    所述终端设备从所述接入网设备接收下行数据。
  13. 如权利要求12所述的方法，其特征在于，所述终端设备从所述接入网设备接收下行数据，包括：
    所述终端设备从所述接入网设备接收随机接入响应消息，所述随机接入响应消息携带NAS PDU，所述NAS PDU包括所述下行数据。
  14. 如权利要求12所述的方法，其特征在于，在所述终端设备从所述接入网设备接收下行数据之前，还包括:
    所述终端设备基于保存的承载配置参数建立所述接入网设备与所述终端设备的数据承载；
    所述终端设备从所述接入网设备接收下行数据，包括：
    所述终端设备从所述接入网设备同步接收随机接入响应消息和所述下行数据，所述下行数据通过所述数据承载携带。
  15. 如权利要求14所述的方法，其特征在于，还包括:
    所述终端设备基于保存的AS安全上下文生成AS安全密钥；
    所述终端设备基于所述AS安全密钥解析所述下行数据。
  16. 如权利要求14所述的方法，其特征在于，所述随机接入响应消息还携带下一跳链路计数器NCC；
    所述方法，还包括：
    所述终端设备基于保存的AS安全上下文和所述NCC生成AS安全密钥；
    所述终端设备基于所述AS安全密钥解析所述下行数据。
  17. 如权利要求13-16任一项所述的方法，其特征在于，所述随机接入响应消息携带上行资源指示信息，所述上行资源指示信息用于指示所述终端设备向所述接入网设备发送所述终端设备是否成功接收所述下行数据的响应消息所采用的时频资源；
    在所述终端设备从所述接入网设备接收下行数据之后，还包括:
    若所述终端设备对所述下行数据解析成功，所述终端设备采用所述上行资源指示信息指示的时频资源向所述接入网设备发送下行数据接收成功响应消息；
    若所述终端设备对所述下行数据解析失败或者所述终端设备没有接收到所述下行数据，所述终端设备采用所述上行资源指示信息指示的时频资源向所述接入网设备发送下行数据接收失败响应消息。
  18. 一种数据传输方法，其特征在于，该方法包括：
    核心网控制面网元获取下行数据指示信息；
    所述核心网控制面网元向接入网设备发送第一消息，所述第一消息包括终端设备的标识。
  19. 如权利要求18所述的方法，其特征在于，核心网控制面网元获取下行数据指示信息，包括：
    所述核心网控制面网元从核心网用户面网元接收下行数据，生成下行数据指示信息；
    或者，所述核心网控制面网元从核心网用户面网元接收下行数据指示信息。
  20. 如权利要求18或19所述的方法，其特征在于，所述下行数据指示信息为单个下行数据包指示信息。
  21. 如权利要求18-20任一项所述的方法，其特征在于，所述第一消息包括所述下行数据指示信息和/或所述下行数据指示信息指示的下行数据；
    或者，所述核心网控制面网元从所述接入网设备接收第三消息，所述第三消息包括所述终端设备的标识，所述第三消息用于请求所述下行数据指示信息指示的下行数据；
    所述核心网控制面网元向所述接入网设备发送第四消息，所述第四消息包括所述下行数据。
  22. 如权利要求21所述的方法，其特征在于，所述终端设备的标识为S-TMSI，所述第一消息或者所述第四消息包括NAS PDU，所述NAS PDU包括所述下行数据。
  23. 如权利要求18-20任一项所述的方法，其特征在于，在所述核心网控制面网元向接入网设备发送第一消息之后，还包括：
    所述核心网控制面网元从所述接入网设备接收第三消息，所述第三消息包括所述终端设备的标识，所述第三消息用于请求所述下行数据指示信息指示的下行数据；
    所述核心网控制面网元向核心网用户面网元发送第七消息，所述第七消息用于指示核心网用户面网元向所述接入网设备发送所述第八消息，所述第八消息包括所述下行数据。
  24. 如权利要求18-21或23任一项所述的方法，其特征在于，所述终端设备的标识包括S-TMSI和第一标识，所述第一标识包括用于获取所述终端设备的上下文的标识；
    在所述核心网控制面网元向接入网设备发送第一消息之后，还包括：
    所述核心网控制面网元从所述接入网设备接收第五消息，所述第五消息包括所述第一标识，所述第五消息用于请求所述终端设备的上下文；
    所述核心网控制面网元向所述接入网设备发送第六消息，所述第六消息包括所述终端设备的上下文，所述终端设备的上下文包括AS安全上下文和/或承载配置参数。
  25. 如权利要求24所述的方法，其特征在于，所述第六消息还包括下一跳链路计数器NCC。
  26. 一种通信装置，其特征在于，用于执行如权利要求1-25任一项所述的方法。
  27. 一种通信装置，其特征在于，包括：处理器，所述处理器与存储器耦合；
    存储器，用于存储计算机程序；
    处理器，用于执行所述存储器中存储的计算机程序，以使得所述装置执行如权利要求1-25任一项所述的方法。
  28. 一种计算机存储介质，其特征在于，存储有计算机指令，当所述指令被执行时，如权利要求1-25任一项所述的方法被执行。
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CN101873707A (zh) * 2009-04-24 2010-10-27 大唐移动通信设备有限公司 下行数据调度方法及系统
CN105530706A (zh) * 2014-10-23 2016-04-27 电信科学技术研究院 一种传输下行数据的方法和设备
CN106162877A (zh) * 2015-04-22 2016-11-23 北京佰才邦技术有限公司 数据传输的方法和设备

Patent Citations (3)

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Publication number Priority date Publication date Assignee Title
CN101873707A (zh) * 2009-04-24 2010-10-27 大唐移动通信设备有限公司 下行数据调度方法及系统
CN105530706A (zh) * 2014-10-23 2016-04-27 电信科学技术研究院 一种传输下行数据的方法和设备
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