WO2020093316A1

WO2020093316A1 - Acknowledgement for downlink early data transmission in paging message

Info

Publication number: WO2020093316A1
Application number: PCT/CN2018/114596
Authority: WO
Inventors: Haitao Li; Srinivasan Selvaganapathy
Original assignee: Nokia Shanghai Bell Co., Ltd.; Nokia Solutions And Networks Oy; Nokia Technologies Oy
Priority date: 2018-11-08
Filing date: 2018-11-08
Publication date: 2020-05-14
Also published as: CN112970301A; CN112970301B

Abstract

Embodiments of the present disclosure relate to methods, devices, apparatuses and computer readable storage media of acknowledgement for downlink early data transmission in a paging message. In example embodiments, a terminal device receives, from an access network device, a paging message carrying downlink (DL) data. The terminal device obtains a preconfigured uplink resource (PUR) region for transmitting a paging response carrying acknowledgement for the DL data. The terminal device transmits the paging response to the access network device in the PUR region.

Description

ACKNOWLEDGEMENT FOR DOWNLINK EARLY DATA TRANSMISSION IN PAGING MESSAGE

FIELD

Embodiments of the present disclosure generally relate to the field of communications, and in particular, to methods, devices, apparatuses and computer readable storage media of acknowledgement for downlink early data transmission in a paging message.

BACKGROUND

Connectionless small data transmission using early data transmission during a random access procedure was discussed for the 3rd Generation Partnership Project (3GPP) Release (Rel-15) . Only uplink (UL) early data transmission was standardized, which is also known as mobile-originated (MO) early data transmission. For 3GPP Release 16 (R-16) , further enhancements for Narrow Band Internet of Things (NB-IoT) are proposed to support early data transmission for downlink (DL) small data.

Mobile-terminated (MT) early data transmission (EDT) is approved to improve downlink (DL) transmission efficiency or UE power consumption. A few options for MT-EDT were discussed, including:

Option 1. MT data in a paging message

Option 2. MT data scheduled in a paging message

Option 3. MT data after a paging message and a PRACH preamble are transmitted

Option 4. MT data in Msg4

Option 1 requires the MT data to be transmitted in a paging message. Option 2 requires the MT data to be scheduled in a paging message. Option 3 requires the MT data to be transmitted after transmission of a paging message and a Physical Random Access Channel (PRACH) preamble. Option 4 requires the MT data to be transmitted in Message 4 (Msg4) during a Random Access (RA) procedure.

Option 1 including the DL data in the paging message can reduce signaling overhead compared with a legacy procedure where the DL data can only be sent after connection is established from user equipment (UE) to an eNodeB (eNB) and further to a mobility management entity (MME) , that is, after a Radio Resource Control (RRC) connection setup complete message is transmitted. In this case, the MME may need to know whether the data is sent to the appropriate UE to determine whether to retransmit or flush the data, for example.

SUMMARY

In general, example embodiments of the present disclosure provide methods, devices, apparatuses and computer readable storage media of acknowledgement for downlink early data transmission in a paging message.

In a first aspect, a method is provided. In the method, a terminal device receives, from an access network device, a paging message carrying downlink data. The terminal device obtains a preconfigured uplink resource region for transmitting a paging response carrying acknowledgement for the downlink data. The terminal device transmits the paging response to the access network device in the preconfigured uplink resource region.

In a second aspect, a method is provided. In the method, an access network device receives, from a core network device, a paging message carrying downlink data towards a terminal device. The access network device forwards the paging message to the terminal device. The access network device receives, from the terminal device, a paging response in a preconfigured uplink resource region for the paging response. The paging response carries acknowledgement for the downlink data. The access network device forwards the paging response to the core network device.

In a third aspect, a method is provided. In the method, a core network device transmits, to an access network device, a paging message carrying downlink data towards a terminal device. The core network device receives, from the access network device, a paging response transmitted by the terminal device in a preconfigured uplink resource region for the paging response. The paging response carries acknowledgement for the downlink data.

In a fourth aspect, a device is provided comprising at least one processor and at least one memory including computer program code. The at least one memory and the computer program code are configured to, with the at least one processor, cause the device to receive, at a terminal device from an access network device, a paging message carrying downlink data. The device is also caused to obtain a preconfigured uplink resource region for transmitting a paging response carrying acknowledgement for the downlink data. The device is further caused to transmit the paging response to the access network device in the preconfigured uplink resource region.

In a fifth aspect, a device is provided comprising at least one processor and at least one memory including computer program code. The at least one memory and the computer program code are configured to, with the at least one processor, cause the device to receive, at an access network device from a core network device, a paging message carrying downlink data towards a terminal device. The device is also caused to forward the paging message to the terminal device. The device is further caused to receive, from the terminal device, a paging response in a preconfigured uplink resource region for the paging response, the paging response carrying acknowledgement for the downlink data. The device is further caused to forward the paging response to the core network device.

In a sixth aspect, a device is provided comprising at least one processor and at least one memory including computer program code. The at least one memory and the computer program code are configured to, with the at least one processor, cause the device to transmit, at a core network device to an access network device, a paging message carrying downlink data towards a terminal device. The device is further caused to receive, from the access network device, a paging response transmitted by the terminal device in a preconfigured uplink resource region for the paging response, the paging response carrying acknowledgement for the downlink data.

In a seventh aspect, there is provided an apparatus comprising means for performing the method according to the first, second or third aspect.

In a sixth aspect, there is provided a computer readable storage medium that stores a computer program thereon. The computer program, when executed by a processor of a device, causes the device to perform the method according to the first, second or third aspect.

It is to be understood that the summary section is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Some example embodiments will now be described with reference to the accompanying drawings, where:

FIG. 1 illustrates an example acknowledgement process at the UE based on the PRACH transmission;

FIG. 2 illustrates an example environment in which embodiments of the present disclosure can be implemented;

FIG. 3 illustrates an example process of information exchange among the core network device, the access network device and the terminal device in accordance to some embodiments of the present disclosure;

FIG. 4 illustrates an example process of information exchange among the core network device, the access network device and the terminal device in accordance to some embodiments of the present disclosure;

FIG. 5 illustrates an example process of information exchange among the core network device, the access network device and the terminal device in accordance to some other embodiments of the present disclosure;

FIG. 6 illustrates a flowchart of an example method in accordance with some embodiments of the present disclosure;

FIG. 7 illustrates a flowchart of an example method in accordance with some other embodiments of the present disclosure;

FIG. 8 illustrates a flowchart of an example method in accordance with some embodiments of the present disclosure; and

FIG. 9 illustrates a simplified block diagram of a device that is suitable for implementing embodiments of the present disclosure.

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

DETAILED DESCRIPTION

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

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

As used herein, the term “access network device” refers to a device via which a terminal device or UE can access a communication network. Examples of the access network device include a relay, an access point (AP) , a transmission point (TRP) , a node B (NodeB or NB) , an evolved NodeB (eNodeB or eNB) , a gigabit NodeB (gNB) , a Remote Radio Module (RRU) , a radio header (RH) , a remote radio head (RRH) , a low power node such as a femto, a pico, and the like.

As used herein, the term “terminal device” or “user equipment” (UE) refers to any terminal device capable of wireless communications with each other or with the access network device. The communications may involve transmitting and/or receiving wireless signals using electromagnetic signals, radio waves, infrared signals, and/or other types of signals suitable for conveying information over air. In some embodiments, the UE may be configured to transmit and/or receive information without direct human interaction. For example, the UE may transmit information to the network device on predetermined schedules, when triggered by an internal or external event, or in response to requests from the network side.

Examples of the UE include, but are not limited to, user equipment (UE) such as smart phones, wireless-enabled tablet computers, laptop-embedded equipment (LEE) , laptop-mounted equipment (LME) , and/or wireless customer-premises equipment (CPE) . For the purpose of discussion, some embodiments will be described with reference to UEs as examples of the terminal devices, and the terms “terminal device” and “user equipment” (UE) may be used interchangeably in the context of the present disclosure.

As used herein, the term “core network device” refers to a device capable of communicating with the access network device and providing services to the UE in a core network. As an example, the core network device may include Mobile Switching Centers (MSCs) , MMEs, Operation and Management (O&M) nodes, Operation Support System (OSS) nodes, Self-Organization Network (SON) nodes, positioning nodes, such as Enhanced Serving Mobile Location Centers (E-SMLCs) , and/or Mobile Data Terminals (MDTs) .

As used herein, the term “circuitry” may refer to one or more or all of the following:

(a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and

(b) combinations of hardware circuits and software, such as (as applicable) : (i) a combination of analog and/or digital hardware circuit (s) with software/firmware and (ii) any portions of hardware processor (s) with software (including digital signal processor (s)) , software, and memory (ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and

(c) hardware circuit (s) and or processor (s) , such as a microprocessor (s) or a portion of a microprocessor (s) , that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.

This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in a server, a cellular network device, or other computing or network device.

As used herein, the singular forms “a” , “an” , and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. The term “includes” and its variants are to be read as open terms that mean “includes, but is not limited to” . The term “based on” is to be read as “based at least in part on” . The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment” . The term “another embodiment” is to be read as “at least one other embodiment” . Other definitions, explicit and implicit, may be included below.

When DL data is sent to a UE in a paging message, the MME may need to know whether the UE has successfully received the data to determine whether to retransmit or flush the data. In this case, the UE may send acknowledgment for the DL data towards the MME. In a conventional UE feedback scheme, the UE may send a paging response to acknowledge the reception of the data after the connection is established with the eNB. Moreover, the paging response is followed by uplink data for application level information in response to an actual network command. The acknowledgment after the establishment of the connection will cause the benefit of DL EDT in term of power saving lost. In addition, this scheme will result in energy inefficient uplink transmission in the network command scenarios.

Another conventional UE feedback scheme is based on Physical Random Access Channel (PRACH) transmission. FIG. 1 shows an example acknowledgement process at the UE based on the PRACH transmission. As shown, a MME transmits (105) to an eNB a paging message carrying a Non-Access Stratum (NAS) protocol data unit (PDU) which encapsulates MT data towards a UE. The eNB sends (110) the paging message together with the allocated PRACH resources to the UE. The UE uses (115) the PRACH resources to initiate the PRACH transmission to acknowledge the reception of the DL data. However, this PRACH-based scheme is not secure enough. A fake UE can use the same preamble to send acknowledgement, and therefore the MME will mistakenly flush the data. In order to ensure the power saving objective of DL EDT, the acknowledgement needs to be sent in an efficient and secure way.

Embodiments of the present disclosure provide an early data transmission scheme in a paging message to reduce signaling overhead and maintain transmission security in uplink as well as downlink. With this scheme, a preconfigured uplink resource (PUR) is allocated for a terminal device to transmit a paging response to acknowledge DL data carried in a paging message. Accordingly, after the terminal device receives the paging message carrying the DL data, the terminal device transmits the paging response carrying the acknowledgement. This scheme allows DL EDT in a paging message without additional signaling overhead of random access procedure for a stationary terminal device or a terminal device with valid timing advance, for example.

FIG. 2 shows an example environment 200 in which embodiments of the present disclosure can be implemented. The environment 200, which is a part of a communication network, includes an access network device 210 and a terminal device 220. The environment 200 also includes a core network device 230 which can communicate with the access network device 210 and with the terminal device 220 via the access network device 210.

It is to be understood that one access network device, one terminal device and one core network device are shown in FIG. 2 only for the purpose of illustration without suggesting any limitation to the scope of the present disclosure. The environment 200 may include any suitable number of access network devices, terminal devices and core network devices adapted for implementing embodiments of the present disclosure.

The terminal device 220 can communicate with the access network device 210 or via the access network device 210 with a further terminal device, or the core network device 230 or other network entities. The communications between the terminal device 220 and the access network device 210 may follow any suitable wireless communication standards or protocols such as Universal Mobile Telecommunications System (UMTS) , long term evolution (LTE) , LTE-Advanced (LTE-A) , the fifth generation (5G) NR, Wireless Fidelity (Wi-Fi) and Worldwide Interoperability for Microwave Access (WiMAX) standards, and employs any suitable communication technologies, including, for example, Multiple-Input Multiple-Output (MIMO) , Orthogonal Frequency Division Multiplexing (OFDM) , time division multiplexing (TDM) , frequency division multiplexing (FDM) , code division multiplexing (CDM) , Bluetooth, ZigBee, and machine type communication (MTC) , enhanced mobile broadband (eMBB) , massive machine type communication (mMTC) and ultra-reliable low latency communication (uRLLC) technologies.

The core network device 230 can communicate with the access network device 210 and other access network devices. The communications between the core network device 230 and the access network device 210 may utilize any suitable communication technology. In some embodiments, the core network device 230 and the access network device 210 may communicate in a cable.

The environment 200 allows DL EDT from the core network device 230 towards the terminal device 220. In various example embodiments of the present disclosures, the core network device 230 transmits DL data towards the terminal device 220 in a paging message to the access network device 210. The access network device 210 allocates a preconfigured uplink resource (PUR) region for the terminal device 220 to transmit a paging response which carries acknowledgement for the DL data. The terminal device 220 uses the PUR region to transmit the paging response to the access network device 210. The access network device 210 forwards the paging response to the core network device 230. Then the DL EDT is complete.

FIG. 3 shows an example process 300 of information exchange among the core network device 230, the access network device 210 and the terminal device 220 in accordance to some embodiments of the present disclosure.

In the process 300, the core network device 230 transmits to the access network device 210 a paging message carrying DL data towards the terminal device 220. For this paging message, a paging response may be transmitted by the terminal device 220 to acknowledge the DL data without triggering a random access channel (RACH) attempt to establish a connection to the core network device 230 via the access network device 210. In some example embodiments, the paging message may further carry a response indication (referred to as a first response indication) to indicate that the paging response is to be transmitted by the terminal device 220 in an early uplink transmission opportunity. In the context of the present disclosure, the early uplink transmission opportunity refers to an uplink transmission opportunity before Message 5 (Msg5) during a RACH procedure, such as a PUR region or Message 3 (Msg3) prior to Msg5.

With the first response indication, the core network device 230 may indicate that a paging response via a NAS message based on the establishment of the connection between the terminal device 220 and the access network device 210 is not required, instead application level acknowledgement, implemented by an UL NAS PDU, should be sent in the next available UL transmission opportunity. Accordingly, the access network device 210 may be aware of the activation of the PUR region for the terminal device 220 to transmit a paging response carrying acknowledgement for the DL data.

It is to be understood that the first response indication is optionally included in the paging message. In some other example embodiments, the first response indication may be transmitted by the core network device 230 to the access network device 210 separately and together with the paging message.

The paging message may further carry some other information related to the paging response. In some example embodiments, the paging message may carry a size indication for a reference size of the paging response. As an example, the reference size may be a proposed maximum size of the paging response. The paging message may also carry the number of repetitions for the paging response to indicate the terminal device 220 to transmit the paging response repeatedly. The number of repetitions of the paging response may be determined by the core network device 230 based on a repetition level associated to the terminal device 220. For example, the number of repetitions may be determined by the core network device 230 based on the last repetition level used by the terminal device 220. Other information related to the paging response is also possible.

After the core network device 230 transmits (305) the paging message to the access network device 210, the access network device 210 forwards (310) the paging message to the terminal device 220. In some example embodiments, the paging message may be forwarded in a paging opportunity (referred to as a first paging opportunity) scheduled in downlink control information (DCI) (referred to as a first DCI) . The first DCI is scrambled based on a paging radio network temporary identifier (P-RNTI) , referred to as a first P-RNTI or an EDT-P-RNTI. The EDT-P-RNTI may be broadcast by the access network device 210 for enabling DL EDT operations. With the EDT-P-RNTI, the terminal device 220 may monitor for the paging message with DL data.

In some example embodiments, the access network device 210 may also transmit a paging message which carries no DL data. Such a paging message may be sent in a paging opportunity (referred to as a second paging opportunity) scheduled in DCI (referred to as second DCI) different from the first DCI. The second DCI is generated based on a different P-RNTI, referred to as a second P-RNTI.

In order to further saving power consumption of the terminal device 220, the second DCI may indicate the presence of the first DCI. In this way, the terminal device 220 can know when to detect the first DCI, thereby avoiding attempt for blind decoding of both the first DCI and the second DCI all the time.

In some example embodiments, before the access network device 210 forwards (310) the paging message, the access network device 210 may modify the paging message by adding a response indication (referred to as a second response indication) to indicate that the paging response is to be transmitted by the terminal device in a PUR region. For example, if the access network device 210 knows that the terminal device 220 is capable of transmission over PUR regions and timing advance of the terminal device 220 is valid, the access network device 210 may add the second response indication into the paging message.

The second response indication may be implemented in an explicit or implicit way. For example, the second response indication may be implemented by information related to the PUR region in an implicit way. In some example embodiments, the information related to the PUR region may be a resource indication (referred to as a first resource indication) of the PUR region. For example, the access network device 210 may determine a PUR region for the terminal device 220 to transmit the paging response and then add the first resource indication of the PUR region as the second response indication into the paging message to implicitly indicate the terminal device 220 to use the PUR region to transmit the paging response. As such, the RACH procedure is avoided to be initiated by the terminal device 220.

The determination of the PUR region may be performed by the access network device 210 after receiving the paging message from the core network device 230. In some example embodiments, before the core network device 230 transmits (305) the paging message with the DL data, the core network device 230 may transmit to the access network device 210 a data indication of the DL data towards the terminal device 220. This data indication may also be carried in a paging message. In these embodiments, the access network device 210 determines the PUR region upon reception of the data indication. Then, the access network device 210 sends first resource indication of the PUR region to the core network device 230. The core network device 230 ciphers the first resource indication and DL data using a NAS security key for the terminal device 210. In this case, the paging message sent (305) carries the ciphered first resource indication and DL data. As such, the PUR region may be informed to the terminal device 220 in a secured way.

The PUR region may be selected by the access network device 210 from a set of PUR regions. The set of PUR regions may be predefined for transmission of a paging response to acknowledge the DL data carried in a paging message. The predefined set of PUR regions may comprise time and frequency resources. In some example embodiments, the predefined PUR regions may be configured periodically in each discontinuous reception (DRX) cycle as a paging message is typically transmitted per DRX cycle.

The predefined PUR regions may be dedicated and different from legacy PUR regions for UL data transmission. For example, each of the predefined PUR regions may have a size below a threshold size. The size may be fixed or dynamically changed. Comparatively, the size of the legacy PUR region for UL data transmission may be larger to accommodate various sizes of UL data. As another example, the predefined PUR regions may have different patterns from the legacy PUR regions. The patterns may include a period, an offset, duration and the like. The patterns of the predefined PUR regions are unnecessarily to align with the patterns of the legacy PUR regions for uplink data.

The predefined set of PUR regions may be indicated to the terminal device 220 in a secure way. In some example embodiments, a resource indication (referred to as a second resource indication) of the predefined set of PUR regions may be transmitted by the access network device 210 to the terminal device 220 via dedicated RRC signaling for the user plane (UP) solution of Consumer Internet of Things (CIoT) optimization. For the control plane (CP) solution of CIoT optimization, the access network device 210 may transmit the second resource indication to the core network device 230, and the core network device 230 may cipher the second resource indication using a NAS security key for the terminal device 220. The core network device 230 sends a NAS message carrying the ciphered second resource indication to the access network device 210, and the access network device 210 forwards the NAS message to the terminal device 220.

As the implementation of the second response indication to indicate that that the paging response is to be transmitted by the terminal device 220 in the PUR region, the information related to the PUR region may be an activation indication of the PUR region. For example, in the embodiments where the predefined set of PUR regions is configured periodically in each DRX cycle, the access network device 210 may use one bit to indicate that the PUR region immediately after the paging message is received is activated for the paging response. The PUR region may be configured in any suitable location in a DRX cycle. In some embodiments, the PUR region may be located at an end of a DRX cycle to further improve the transmission efficiency and reduce the transmission delay of the paging response. In this case, if there is no paging message in a DRX cycle, the PUR region associated with this DRX cycle can be reused for other transmissions to further improve the resource utilization.

In some example embodiments, the predefined PUR regions may be associated with a timer to avoid reservation of resources for longer duration. When the access network device 210 determines the PUR region, if the timer associated with the determined PUR region expires, the access network device 210 may trigger acknowledgement for the DL data during a RACH procedure.

After the access network device 210 forwards (310) the paging message to the terminal device 220, the terminal device 220 obtains (315) the PUR region. In the embodiments where the first resource indication of the PUR region is indicated in the forwarded paging message, the terminal device 220 may obtain the PUR region from the paging message. In the embodiments where the predefined set of PUR regions is configured periodically in each DRX cycle, the terminal device 220 may determine the PUR region after the end of the DRX cycle, in which the paging message is received, for use in transmitting the paging response.

The PUR region may be shared by UEs. As an example, the PUR region may comprise a few PUR occasions which are contention based. In this case, the terminal device 220 may detect an available PUR occasion based on contention. As another example, the PUR occasions may be contention free. A predetermined PUR occasion may be allocated to the terminal device 220 where the access network device 210 expects to receive the paging response.

In some example embodiments, the terminal device 220 may first determine whether the paging response is to be transmitted using the PUR region. For example, the terminal device 220 may make this determination based on the explicit or implicit indication, as described above, inserted by the access network device 210 into the paging message. If the explicit or implicit indication indicates that the paging response is to be transmitted using the PUR region, the terminal device 220 can determine that the paging response is to be transmitted using the PUR region.

In the embodiments where the paging message from the core network device 210 carries the first response indication that the paging response is to be transmitted by the terminal device in an early uplink transmission opportunity, the access network device 220 may forwards the first response indication together with the paging message. In this case, ifthe explicit or implicit indication is not inserted by the access network device 210 in the paging message to indicate that the paging response is to be transmitted using the PUR region, the terminal device 220 may determine, based on the first response indication, that the acknowledgment may be sent using MO EDT procedure, such as Msg3. If none of the above indications are included in the paging message, the terminal device 220 may trigger a RACH procedure to send the paging response.

In some example embodiments, the paging response may be sent by the terminal device 220 repeatedly in the PUR region. In the example embodiments where the number of repetitions of the paging response is determined by the core network device 230, the terminal device 220 may receive the repetition indication of the number of repetitions via the access network device 210 from the core network device 230. The number of repetitions may be also determined by the access network device 210 and indicated to the terminal device 220.

After obtaining (315) the PUR region, the terminal device 220 transmits (320) the paging response to the access network device 210 in the PUR region, and the paging response carries the acknowledgement for the DL data. The acknowledgement may comprise a positive or negative acknowledgement. For example, the terminal device 220 may send a positive acknowledgement after decoding the paging message and data successfully. If the decoding is failed, the terminal device 220 may send a negative acknowledgement. The acknowledgement may be implemented by application level information such as a NAS PDU.

In some example embodiments, the paging response may further include an identifier (ID) of the terminal device 220. With this ID, the access network device 210 may know which terminal device transmits the paging response. In particular in the case that the PUR region is contention based, the access network device 210 may use the ID for contention resolution.

After the terminal device 220 transmits (320) the paging response to the access network device 210, the access network device 210 forwards (325) the paging response to the core network device 230. Then, the DL EDT completes.

FIG. 4 shows an example process 400 of information exchange among the core network device 230, the access network device 210 and the terminal device 220 in accordance to some embodiments of the present disclosure.

In the process 400, the access network device 210 (for example, the eNB) configures PUR regions for a paging response carrying acknowledgement for DL data carried by a paging message, and then access network device 210 sends the PUR regions to the terminal device 220 (for example, UE) in a security way (405) . When the terminal device 220 is in an idle mode (410) , the core network device 230 (for example, MME) transmits (415) a paging message carrying DL data which is ciphered using a security key specific to the terminal device 220.

The access network device 210 determines (420) the PUR region for the terminal device 220 to transmit the paging response. The access network device 210 adds the first resource indication of the determined PUR into the paging message and then forwards the paging message to the terminal device 220 (425) . The terminal device 220 decodes (430) the DL data successfully. Then, the terminal device 220 sends (435) the paging response to the access network device 210 in the PUR region where the paging response carries a positive acknowledgement. The access network device 210 forwards (440) the paging response to the core network device 230.

FIG. 5 shows an example process 500 of information exchange among the core network device 230, the access network device 210 and the terminal device 220 in accordance to some other embodiments of the present disclosure.

In the process 500, the access network device 210 (for example, the eNB) configures PUR regions for a paging response carrying acknowledgement for DL data carried by a paging message, and then access network device 210 sends the PUR regions to the terminal device 220 (for example, UE) in a security way (505) . When the terminal device 220 is in an idle mode (410) , the core network device 230 (for example, MME) transmits (515) , in a paging message, a data indication of the DL data towards the terminal device 210.

The access network device 210 determines (520) the PUR region for the terminal device 220 to transmit the paging response. Then, the access network device 210 transmits (522) the first resource indication of the determined PUR to the core network device 230. The core network device 230 ciphers the first resource indication and the DL data using a security key specific to the terminal device 220, and sends, to the access network device 210, the paging message carrying the ciphered first resource indication and DL data (524) .

The access network device 210 forwards (525) the paging message to the terminal device 220. The terminal device 220 decodes (530) the DL data successfully, and sends (535) the paging response to the access network device 210 in the PUR region where the paging response carries a positive acknowledgement. The access network device 210 forwards (540) the paging response to the core network device 230.

FIG. 6 shows a flowchart of an example method 600 in accordance with some other embodiments of the present disclosure. The method 600 can be implemented at the terminal device 220 as shown in FIG. 2. For the purpose of discussion, the method 600 will be described with reference to FIG. 2.

At block 605, the terminal device 220 receives from the access network device 210 a paging message carrying DL data. At block 610, the terminal device 220 obtains a PUR region for transmitting a paging response carrying acknowledgement for the DL data. At block 615, the terminal device 220 transmits the paging response to the access network device 210 in the PUR region.

In some example embodiments, the terminal device 220 may detect the first DCI using the first P-RNTI. The first DCI indicates the first paging opportunity to be used for forwarding the paging message. The terminal device 220 may determine the first paging opportunity from the first DCI and receive the paging message from the access network device 210 in the first paging opportunity.

In some example embodiments, the terminal device 220 may detect the second DCI using the second P-RNTI different from the first P-RNTI. The second DCI indicates the second paging opportunity for transmitting a paging message without DL data towards the terminal device 220. The terminal device 220 may determine the second paging opportunity from the second DCI and receive, from the access network device 210 in the second paging opportunity, the paging message without the DL data. In some example embodiments, the terminal device 220 may receive the first P-RNTI broadcasted by the access network device.

In some example embodiments, the second DCI may further indicate that the first DCI is to be detected by the terminal device 220.

In some example embodiments, the paging message may further carry the first response indication from the core network device 230 to indicate that the paging response is to be transmitted by the terminal device 220 in an early uplink transmission opportunity. In some example embodiments, the paging message may further carry a size indication from the core network device 230 for a reference size of the paging response.

In some example embodiments, the paging message may further carry the second response indication for indicating that the paging response is to be transmitted by the terminal device 220 in the PUR region. In some example embodiments, the second response indication may comprise the first resource indication of the preconfigured uplink resource region.

In some example embodiments, the terminal device 220 may receive the second resource indication of a predefined set of PUR regions. The PUR region is obtained by the terminal device 220 from the predefined set of PUR regions. In some example embodiments, a size of each of the preconfigured uplink resource regions may be below a threshold size.

In some example embodiments, the predefined set of PUR regions may be configured periodically in each discontinuous reception cycle. The second response indication may comprise an activation indication to indicate that the PUR region in the predefined set of PUR regions immediately after the paging message is received is to be activated for transmitting the paging response.

In some example embodiments, the terminal device 220 may receive the second resource indication from the access network device 210 via dedicated signaling. In some example embodiments, the terminal device 220 may receive, from the access network device 210, the second resource indication ciphered by the core network device 230 using a non-access stratum security key for the terminal device 220.

In some example embodiments, the paging message is forwarded in a DRX cycle, and the PUR region is located at an end of the DRX cycle. In some example embodiments, the PUR region is associated with a timer. In these example embodiments, the terminal device 220 may transmit the paging response to the access network device 210 in the PUR region if the timer is unexpired.

In some example embodiments, the terminal device 220 may receive, from the access network device 210, a repetition indication of the number of repetitions for the paging response. The number of repetitions may be determined by the core network device 230 based on a reference repetition level associated with the terminal device 210.

In some example embodiments, the paging response further carries an ID of the terminal device 210.

FIG. 7 shows a flowchart of an example method 700 in accordance with some other embodiments of the present disclosure. The method 700 can be implemented at the access network device 210 as shown in FIG. 2. For the purpose of discussion, the method 700 will be described with reference to FIG. 2.

At block 705, the access network device 210 receives from the core network device 230 a paging message carrying DL data towards the terminal device 220. At block 710, the access network device 210 forwards the paging message to the terminal device 220. At block 715, the access network device 210 receives, from the terminal device 220, a paging response in a PUR region for the paging response. The paging response carries acknowledgement for the DL data. At block 720, the access network device 210 forwards the paging response to the core network device 230.

In some example embodiments, the access network device 210 may generating the first DCI based on the first P-RNTI. The first DCI indicates the first paging opportunity to be used for forwarding the paging message. The access network device 210 may forward the paging message to the terminal device 220 in the first paging opportunity.

In some example embodiments, the access network device 210 may generate the second DCI based on the second P-RNTI different from the first P-RNTI. The second DCI indicates the second paging opportunity for transmitting a paging message without DL data towards the terminal device 220. The access network device 210 may transmit, to the terminal device 220 in the second paging opportunity, the paging message without the DL data. In some example embodiments, the access network device 210 may broadcast the first P-RNTI.

In some example embodiments, the paging message from the core network device 230 may further carry the first response indication to indicate that the paging response is to be transmitted by the terminal device 220 in an early uplink transmission opportunity. In some example embodiments, the paging message from the core network device 230 may further carry a size indication from the core network device 230 for a reference size of the paging response.

In some example embodiments, the access network device 210 may modify the paging message by adding the second response indication to indicate that the paging response is to be transmitted by the terminal device 210 in the PUR region. Then, the access network device 210 may forward the modified paging message to the terminal device 220. In some example embodiments, the access network device 210 may determine the PUR region and add the first resource indication of the PUR region into the paging message as the second response indication.

In some example embodiments, the access network device 210 may receive the data indication of the downlink data from the core network device 230. In response to the data indication, the access network device 210 may determine the PUR region. The access network device 210 may transmit the first resource indication of the PUR region to the core network device 230. Then, the access network device 210 may receive, from the core network device 230, the paging message carrying the first resource indication and downlink data ciphered by the core network device 230 using the NAS key for the terminal device 220.

In some example embodiments, the access network device 210 may select the PUR region from a predefined set of PUR regions. In some example embodiments, the access network device 210 may transmit the second resource indication of the predefined set of PUR regions to the terminal device 220. In some example embodiments, the access network device 210 may transmit the second resource indication to the terminal device 220 via dedicated RRC signaling.

In some example embodiments, the access network device 210 may transmit the second resource indication to the core network device 230. The access network device 210 may receive from the core network device 230 the second resource indication ciphered by the core network device 230 using the NAS security key for the terminal device 220. Then, the access network device 210 may forward the ciphered second resource indication to the terminal device 220.

In some example embodiments, a size of each of the preconfigured uplink resource regions may be below a threshold size. In some example embodiments, the predefined set of PUR regions may be configured periodically in each discontinuous reception cycle. The second response indication may comprise an activation indication to indicate that the PUR region in the predefined set of PUR regions immediately after paging message is received is to be activated for transmitting the paging response.

In some example embodiments, the paging message is forwarded in a DRX cycle, and the PUR region is located at an end of the DRX cycle. In some example embodiments, the PUR region is associated with a timer. In these example embodiments, the access network device 210 may receive the paging response from the terminal device 220 in the PUR region before the timer expires.

In some example embodiments, the access network device 210 may receive from the core network device, a repetition indication of the number of repetitions for the paging response. The number of repetitions may be determined by the core network device 230 based on a reference repetition level associated with the terminal device 220. Then, the access network device 210 may forward the repetition indication to the terminal device 220.

FIG. 8 shows a flowchart of an example method 800 in accordance with some other embodiments of the present disclosure. The method 800 can be implemented at the core network device 230 as shown in FIG. 2. For the purpose of discussion, the method 800 will be described with reference to FIG. 2.

At block 805, the core network device 230 transmits to the access network device 210 a paging message carrying DL data towards the terminal device 220. At block 810, the core network device 230 receives, from the access network device 210, a paging response transmitted by the terminal device 220 in a PUR region for the paging response. The paging response carries acknowledgement for the DL data.

In some example embodiments, the paging message may further carry the first response indication to indicate that the paging response is to be transmitted by the terminal device 220 in an early uplink transmission opportunity. In some example embodiments, the paging message may further carry a size indication from the core network device 230 for a reference size of the paging response.

In some example embodiments, the core network device 230 may send the data indication of the DL data to the access network device 210. The core network device 230 may receive the first resource indication of the PUR region from the access network device 210. Then, the core network device 230 may cipher the first resource indication and DL data using the NAS security key for the terminal device 210. The core network device 230 may transmit, to the access network device 210, the paging message carrying the ciphered first resource indication and DL data.

In some example embodiments, the core network device 230 may determine the number of repetitions for the paging response based on a reference repetition level associated with the terminal device 220. The core network device 230 may send the repetition indication of the number of repetitions to the access network device 210.

All operations and features as described above with reference to FIGS. 2 to 5 are likewise applicable to the

methods

600, 700 and 800 and have similar effects. For the purpose of simplification, the details will be omitted.

In some embodiments, an apparatus capable of performing the

method

400 or 800 may comprise means for performing the respective steps of the

method

600, 700 or 800. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

In some example embodiments, the apparatus capable of performing the method 600 comprises: means for receiving, at a terminal device from an access network device, a paging message carrying downlink data; means for obtaining a preconfigured uplink resource region for transmitting a paging response carrying acknowledgement for the downlink data; and means for transmitting the paging response to the access network device in the preconfigured uplink resource region.

In some example embodiments, the means for receiving the paging message may comprise: means for detecting first downlink control information using a first paging radio network temporary identifier, the first downlink control information indicating a first paging opportunity to be used for forwarding the paging message; means for determining the first paging opportunity from the first downlink control information; and means for receiving the paging message from the access network device in the first paging opportunity.

In some example embodiments, the apparatus may further comprise: means for detecting second downlink control information using a second paging radio network temporary identifier different from the first paging radio network temporary identifier, the second downlink control information indicating a second paging opportunity for transmitting a paging message without downlink data towards the terminal device; means for determining the second paging opportunity from the second downlink control information; and means for receiving, from the access network device in the second paging opportunity, the paging message without the downlink data.

In some example embodiments, the second downlink control information may further indicate that the first downlink control information is to be detected by the terminal device.

In some example embodiments, the apparatus may further comprise: means for receiving the first paging radio network temporary identifier broadcasted by the access network device.

In some example embodiments, the paging message may further carry a first response indication from the core network device to indicate that the paging response is to be transmitted by the terminal device in an early uplink transmission opportunity.

In some example embodiments, the paging message may further carry a size indication from the core network device for a reference size of the paging response.

In some example embodiments, the paging message may further carry a second response indication for indicating that the paging response is to be transmitted by the terminal device in the preconfigured uplink resource region.

In some example embodiments, the second response indication may comprise a first resource indication of the preconfigured uplink resource region.

In some example embodiments, the apparatus may further comprise: means for receiving a second resource indication of a predefined set of preconfigured uplink resource regions, wherein the preconfigured uplink resource region is obtained from the predefined set of preconfigured uplink resource regions.

In some example embodiments, the predefined set of preconfigured uplink resource regions may be configured periodically in each discontinuous reception cycle. The second response indication may comprise an activation indication to indicate that the preconfigured uplink resource region in the predefined set of preconfigured uplink resource regions immediately after the paging message is received is to be activated for transmitting the paging response.

In some example embodiments, the means for receiving the second resource indication may comprise: means for receiving the second resource indication from the access network device via dedicated RRC signaling.

In some example embodiments, the means for receiving the second resource indication may comprise: means for receiving, from the access network device, the second resource indication ciphered by the core network device using a non-access stratum security key for the terminal device.

In some example embodiments, a size of each of the preconfigured uplink resource regions may be below a threshold size.

In some example embodiments, the paging message may be forwarded in a discontinuous reception cycle. The preconfigured uplink resource region may be located at an end of the discontinuous reception cycle.

In some example embodiments, the preconfigured uplink resource region may be associated with a timer. The means for transmitting the paging response may comprise: means for in response to the timer being unexpired, transmitting the paging response to the access network device in the preconfigured uplink resource region.

In some example embodiments, the apparatus may further comprise: means for receiving, from the access network device, a repetition indication of the number of repetitions for the paging response, the number of repetitions being determined by the core network device based on a reference repetition level associated with the terminal device.

In some example embodiments, the paging response further may carry an identifier of the terminal device.

In some example embodiments, the apparatus capable of performing the method 700 comprises: means for receiving, at an access network device from a core network device, a paging message carrying downlink data towards a terminal device; means for forwarding the paging message to the terminal device; means for receiving, from the terminal device, a paging response in a preconfigured uplink resource region for the paging response, the paging response carrying acknowledgement for the downlink data; and means for forwarding the paging response to the core network device.

In some example embodiments, the means for forwarding the paging message may comprise: means for generating first downlink control information based on a first paging radio network temporary identifier, the first downlink control information indicating a first paging opportunity to be used for forwarding the paging message; and means for forwarding the paging message to the terminal device in the first paging opportunity.

In some example embodiments, the apparatus may further comprise: means for generating second downlink control information based on a second paging radio network temporary identifier different from the first paging radio network temporary identifier, the second downlink control information indicating a second paging opportunity for transmitting a paging message without downlink data towards the terminal device; and means for transmitting, to the terminal device in the second paging opportunity, the paging message without the downlink data.

In some example embodiments, the apparatus may further comprise: means for broadcasting the first paging radio network temporary identifier.

In some example embodiments, the paging message from the core network device may further carry a first response indication for indicating that the paging response is to be transmitted by the terminal device in an early uplink transmission opportunity.

In some example embodiments, the paging message from the core network device may further carry a size indication for a reference size of the paging response.

In some example embodiments, the means for forwarding the paging message may comprise: means for modifying the paging message by adding a second response indication to indicate that the paging response is to be transmitted by the terminal device in the preconfigured uplink resource region; and means for forwarding the modified paging message to the terminal device.

In some example embodiments, the means for modifying the paging message may comprise: means for determining the preconfigured uplink resource region; and means for adding a first resource indication of the preconfigured uplink resource region into the paging message as the second response indication.

In some example embodiments, the means for receiving the paging message may comprise: means for receiving a data indication of the downlink data from the core network device; means for determining the preconfigured uplink resource region; means for transmitting a first resource indication of the preconfigured uplink resource region to the core network device; and means for receiving, from the core network device, the paging message carrying the first resource indication and downlink data ciphered by the core network device using a non-access stratum security key for the terminal device.

In some example embodiments, the means for determining the preconfigured uplink resource region may comprise: means for selecting the preconfigured uplink resource region from a predefined set ofpreconfigured uplink resource regions.

In some example embodiments, the apparatus may further comprise: means for transmitting a second resource indication of the predefined set of preconfigured uplink resource regions to the terminal device.

In some example embodiments, the means for transmitting the second resource indication may comprise: means for transmitting the second resource indication to the terminal device via dedicated RRC signaling.

In some example embodiments, the means for transmitting the second resource indication may comprise: means for transmitting the second resource indication to the core network device; means for receiving, from the core network device, the second resource indication ciphered by the core network device using a non-access stratum security key for the terminal device; and means for forwarding the ciphered second resource indication to the terminal device.

In some example embodiments, a set ofpreconfigured uplink resource regions may be predefined periodically in each discontinuous reception cycle. The second response indication may comprise an activation indication to indicate that the preconfigured uplink resource region in the predefined set of preconfigured uplink resource regions immediately after the paging message is received is to be activated for transmitting the paging response.

In some example embodiments, the preconfigured uplink resource region may be associated with a timer. The means for receiving the paging response may comprise: means for receiving the paging response from the terminal device in the preconfigured uplink resource region before the timer is expired.

In some example embodiments, the apparatus may further comprise: means for receiving, from the core network device, a repetition indication of the number of repetitions for the paging response, the number of repetitions being determined by the core network device based on a reference repetition level associated with the terminal device; and means for forwarding the repetition indication to the terminal device.

In some example embodiments, the paging response may further carry an identifier of the terminal device.

In some example embodiments, the apparatus capable of performing the method 800 comprises: means for transmitting, at a core network device to an access network device, a paging message carrying downlink data towards a terminal device; and means for receiving, from the access network device, a paging response transmitted by the terminal device in a preconfigured uplink resource region for the paging response, the paging response carrying acknowledgement for the downlink data.

In some example embodiments, the paging message may further carries a size indication for a reference size of the paging response.

In some example embodiments, the means for transmitting the paging message may comprise: means for sending a data indication of the downlink data to the access network device; means for receiving a first resource indication of the preconfigured uplink resource region from the access network device; means for ciphering the first resource indication and downlink data using a non-access stratum security key for the terminal device; and means for transmitting, to the access network device, the paging message carrying the ciphered first resource indication and downlink data.

In some example embodiments, the apparatus may further comprise: means for determining the number of repetitions for the paging response based on a reference repetition level associated with the terminal device; and means for sending a repetition indication of the number of repetitions to the access network device.

In some example embodiments, the paging message may further carry a first response indication to indicate that the paging response is to be transmitted by the terminal device in an early uplink transmission opportunity.

FIG. 9 is a simplified block diagram of a device 900 that is suitable for implementing embodiments of the present disclosure. The device 900 can be implemented at the terminal device 220, the access network device 210 or the core network device 230 as shown in FIG. 2.

As shown, the device 900 includes a processor 910, a memory 920 coupled to the processor 910, a communication module 930 coupled to the processor 910, and a communication interface (not shown) coupled to the communication module 930. The memory 920 stores at least a program 940. The communication module 930 is for bidirectional communications, for example, via multiple antennas. The communication interface may represent any interface that is necessary for communication.

The program 940 is assumed to include program instructions that, when executed by the associated processor 910, enable the device 900 to operate in accordance with the embodiments of the present disclosure, as discussed herein with reference to FIGS. 2-8. The embodiments herein may be implemented by computer software executable by the processor 910 of the device 900, or by hardware, or by a combination of software and hardware. The processor 910 may be configured to implement various embodiments of the present disclosure.

The memory 920 may be of any type suitable to the local technical network and may be implemented using any suitable data storage technology, such as a non-transitory computer readable storage medium, semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory, as non-limiting examples. While only one memory 920 is shown in the device 900, there may be several physically distinct memory modules in the device 900. The processor 910 may be of any type suitable to the local technical network, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 900 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

When the device 900 acts as the terminal device 220 or a part of the terminal device 220, the processor 910 and the communication module 930 may cooperate to implement the method 600 as described above with reference to FIGS. 2-6. When the device 900 acts as the access network device 210 or a part of the access network device 210, the processor 910 and the communication module 930 may cooperate to implement the method 700 as described above with reference to FIGS. 2-5 and 7. When the device 900 acts as the core network device 230 or a part of the core network device 230, the processor 910 and the communication module 930 may cooperate to implement the method 800 as described above with reference to FIGS. 2-5 and 8. All operations and features as described above with reference to FIGS. 2-8 are likewise applicable to the device 900 and have similar effects. For the purpose of simplification, the details will be omitted.

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

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor, to carry out the methods 600 to 800 as described above with reference to FIGS. 2-8. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

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

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

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

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

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

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

Claims

A method comprising:

receiving, at a terminal device from an access network device, a paging message carrying downlink data;

obtaining a preconfigured uplink resource region for transmitting a paging response carrying acknowledgement for the downlink data; and

transmitting the paging response to the access network device in the preconfigured uplink resource region.
The method of claim 1, wherein receiving the paging message comprises:

detecting first downlink control information using a first paging radio network temporary identifier, the first downlink control information indicating a first paging opportunity to be used for forwarding the paging message;

determining the first paging opportunity from the first downlink control information; and

receiving the paging message from the access network device in the first paging opportunity.
The method of claim 2, further comprising:

detecting second downlink control information using a second paging radio network temporary identifier different from the first paging radio network temporary identifier, the second downlink control information indicating a second paging opportunity for transmitting a paging message without downlink data towards the terminal device;

determining the second paging opportunity from the second downlink control information; and

receiving, from the access network device in the second paging opportunity, the paging message without the downlink data.
The method of claim 3, wherein the second downlink control information further indicates that the first downlink control information is to be detected by the terminal device.
The method of any of claims 2-4, further comprising:

receiving the first paging radio network temporary identifier broadcasted by the access network device.
The method of claim 1, wherein the paging message further carries a first response indication from the core network device to indicate that the paging response is to be transmitted by the terminal device in an early uplink transmission opportunity.
The method of claim 1, wherein the paging message further carries a size indication from the core network device for a reference size of the paging response.
The method of claim 1, wherein the paging message further carries a second response indication for indicating that the paging response is to be transmitted by the terminal device in the preconfigured uplink resource region.
The method of claim 8, wherein the second response indication comprises a first resource indication of the preconfigured uplink resource region.
The method of claim 8, further comprising:

receiving a second resource indication of a predefined set of preconfigured uplink resource regions,

wherein the preconfigured uplink resource region is obtained from the predefined set of preconfigured uplink resource regions.
The method of claim 10, wherein the predefined set of preconfigured uplink resource regions is configured periodically in each discontinuous reception cycle, and

wherein the second response indication comprises an activation indication to indicate that the preconfigured uplink resource region in the predefined set of preconfigured uplink resource regions immediately after the paging message is received is to be activated for transmitting the paging response.
The method of claim 10 or 11, wherein receiving the second resource indication of the predefined set of preconfigured uplink resource regions comprises:

receiving the second resource indication from the access network device via dedicated radio resource control signaling.
The method of claim 10 or 11, wherein receiving the second resource indication of the predefined set of preconfigured uplink resource regions comprises:

receiving, from the access network device, the second resource indication ciphered by the core network device using a non-access stratum security key for the terminal device.
The method of claim 10, wherein a size of each of the preconfigured uplink resource regions is below a threshold size.
The method of claim 1, wherein the paging message is forwarded in a discontinuous reception cycle, and the preconfigured uplink resource region is located at an end of the discontinuous reception cycle.
The method of claim 1, wherein the preconfigured uplink resource region is associated with a timer, and transmitting the paging response comprises:

in response to the timer being unexpired, transmitting the paging response to the access network device in the preconfigured uplink resource region.
The method of claim 1, further comprising:

receiving, from the access network device, a repetition indication of the number of repetitions for the paging response, the number of repetitions being determined by the core network device based on a reference repetition level associated with the terminal device.
The method of claim 1, wherein the paging response further carries an identifier of the terminal device.
A method comprising:

receiving, at an access network device from a core network device, a paging message carrying downlink data towards a terminal device;

forwarding the paging message to the terminal device;

receiving, from the terminal device, a paging response in a preconfigured uplink resource region for the paging response, the paging response carrying acknowledgement for the downlink data; and

forwarding the paging response to the core network device.
The method of claim 19, wherein forwarding the paging message comprises:

generating first downlink control information based on a first paging radio network temporary identifier, the first downlink control information indicating a first paging opportunity to be used for forwarding the paging message; and

forwarding the paging message to the terminal device in the first paging opportunity.
The method of claim 20, further comprising:

generating second downlink control information based on a second paging radio network temporary identifier different from the first paging radio network temporary identifier, the second downlink control information indicating a second paging opportunity for transmitting a paging message without downlink data towards the terminal device; and

transmitting, to the terminal device in the second paging opportunity, the paging message without the downlink data.
The method of claim 21, wherein the second downlink control information further indicates that the first downlink control information is to be detected by the terminal device.
The method of any of claims 20-22, further comprising:

broadcasting the first paging radio network temporary identifier.
The method of claim 19, wherein the paging message from the core network device further carries a first response indication for indicating that the paging response is to be transmitted by the terminal device in an early uplink transmission opportunity.
The method of claim 19, wherein the paging message from the core network device further carries a size indication for a reference size of the paging response.
The method of claim 19, wherein forwarding the paging message comprises:

modifying the paging message by adding a second response indication to indicate that the paging response is to be transmitted by the terminal device in the preconfigured uplink resource region; and

forwarding the modified paging message to the terminal device.
The method of claim 26, wherein modifying the paging message comprises:

determining the preconfigured uplink resource region; and

adding a first resource indication of the preconfigured uplink resource region into the paging message as the second response indication.
The method of claim 19, wherein receiving the paging message comprises:

receiving a data indication of the downlink data from the core network device;

determining the preconfigured uplink resource region;

transmitting a first resource indication of the preconfigured uplink resource region to the core network device; and

receiving, from the core network device, the paging message carrying the first resource indication and downlink data ciphered by the core network device using a non-access stratum security key for the terminal device.
The method of claim 27 or 28, wherein determining the preconfigured uplink resource region comprises:

selecting the preconfigured uplink resource region from a predefined set of preconfigured uplink resource regions.
The method of claim 29, further comprising:

transmitting a second resource indication of the predefined set of preconfigured uplink resource regions to the terminal device.
The method of claim 30, wherein transmitting the second resource indication comprises:

transmitting the second resource indication to the terminal device via dedicated radio resource control signaling.
The method of claim 30, wherein transmitting the second resource indication comprises:

transmitting the second resource indication to the core network device;

receiving, from the core network device, the second resource indication ciphered by the core network device using a non-access stratum security key for the terminal device; and

forwarding the ciphered second resource indication to the terminal device.
The method of claim 29, wherein a size of each of the preconfigured uplink resource regions is below a threshold size.
The method of claim 26, wherein a set of preconfigured uplink resource regions are predefined periodically in each discontinuous reception cycle, and

wherein the second response indication comprises an activation indication to indicate that the preconfigured uplink resource region in the predefined set of preconfigured uplink resource regions immediately after the paging message is received is to be activated for transmitting the paging response.
The method of claim 19, wherein the paging message is forwarded in a discontinuous reception cycle, and the preconfigured uplink resource region is located at an end of the discontinuous reception cycle.
The method of claim 19, wherein the preconfigured uplink resource region is associated with a timer, and receiving the paging response comprises:

receiving the paging response from the terminal device in the preconfigured uplink resource region before the timer is expired.
The method of claim 19, further comprising:

receiving, from the core network device, a repetition indication of the number of repetitions for the paging response, the number of repetitions being determined by the core network device based on a reference repetition level associated with the terminal device; and

forwarding the repetition indication to the terminal device.
The method of claim 19, wherein the paging response further carries an identifier of the terminal device.
A method comprising:

transmitting, at a core network device to an access network device, a paging message carrying downlink data towards a terminal device; and

receiving, from the access network device, a paging response transmitted by the terminal device in a preconfigured uplink resource region for the paging response, the paging response carrying acknowledgement for the downlink data.
The method of claim 39, wherein the paging message further carries a size indication for a reference size of the paging response.
The method of claim 39, wherein transmitting the paging message comprises:

sending a data indication of the downlink data to the access network device;

receiving a first resource indication of the preconfigured uplink resource region from the access network device;

ciphering the first resource indication and downlink data using a non-access stratum security key for the terminal device; and

transmitting, to the access network device, the paging message carrying the ciphered first resource indication and downlink data.
The method of claim 39, further comprising:

determining the number of repetitions for the paging response based on a reference repetition level associated with the terminal device; and

sending a repetition indication of the number of repetitions to the access network device.
The method of claim 39, wherein the paging message further carries a first response indication to indicate that the paging response is to be transmitted by the terminal device in an early uplink transmission opportunity.
A device comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the device to perform the method according to any of claims 1-18.
A device comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the device to perform the method according to any of claims 19-38.
A device comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the device to perform the method according to any of claims 39-43.
An apparatus comprising:

means for receiving, at a terminal device from an access network device, a paging message carrying downlink data;

means for obtaining a preconfigured uplink resource region for transmitting a paging response carrying acknowledgement for the downlink data; and

means for transmitting the paging response to the access network device in the preconfigured uplink resource region.
An apparatus comprising:

means for receiving, at an access network device from a core network device, a paging message carrying downlink data towards a terminal device;

means for forwarding the paging message to the terminal device;

means for receiving, from the terminal device, a paging response in a preconfigured uplink resource region for the paging response, the paging response carrying acknowledgement for the downlink data; and

means for forwarding the paging response to the core network device.
An apparatus comprising:

means for transmitting, at a core network device to an access network device, a paging message carrying downlink data towards a terminal device; and

means for receiving, from the access network device, a paging response transmitted by the terminal device in a preconfigured uplink resource region for the paging response, the paging response carrying acknowledgement for the downlink data.
A computer readable storage medium comprising program instructions stored thereon, the instructions, when executed by a processor of a device, causing the device to perform the method of any of claims 1-18.
A computer readable storage medium comprising program instructions stored thereon, the instructions, when executed by a processor of a device, causing the device to perform the method of any of claims 19-38.
A computer readable storage medium comprising program instructions stored thereon, the instructions, when executed by a processor of a device, causing the device to perform the method of any of claims 39-43.