CN109996197B

CN109996197B - Method and equipment for transmitting short message

Info

Publication number: CN109996197B
Application number: CN201810002098.2A
Authority: CN
Inventors: 璋风兢; 谷群
Original assignee: China Mobile Communications Group Co Ltd; China Mobile Communications Ltd Research Institute
Current assignee: China Mobile Communications Group Co Ltd; China Mobile Communications Ltd Research Institute
Priority date: 2018-01-02
Filing date: 2018-01-02
Publication date: 2021-08-06
Anticipated expiration: 2038-01-02
Also published as: CN109996197A

Abstract

The invention discloses a method and equipment for transmitting short messages, which are used for solving the problems that cached short messages are easy to lose when a user moves across MME and the short message transmission reliability is poor in the prior art. In the embodiment of the invention, after the terminal moves across the MME, the MME connected before the terminal moves across the MME sends the cached short message to the MME currently connected with the terminal in the TAU process of the terminal, or sends the cached short message to the network system where the terminal is currently located through the service gateway after the TAU process of the terminal, so that the loss of the short message session message cached in the MME originally connected due to the fact that the position of the terminal moves into a new MME can be avoided; and further, the reliability of the short message service of the Internet of things is improved.

Description

Method and equipment for transmitting short message

Technical Field

The present invention relates to the field of core networks, and in particular, to a method and an apparatus for transmitting short messages.

Background

With the development of the internet of things technology, operators need to develop various new services and improve the existing services. The short message service is an important existing service, and in the existing PSM (power saving mode) and eDRX (Extended idle mode DRX) energy saving modes of NB-IoT (Narrow Band Internet of Things based on cellular), the caching of short messages may have some problems.

In the PSM state in NB-IoT, the radio frequency of the terminal is closed, in the state, the terminal does not receive downlink data, and in the eDRX state in NB-IoT, in order to achieve the purpose of power saving, the core network and the terminal reach an agreement, and most of idle paging monitoring is skipped. In this way, in PSM and eDRX states in NB-IoT, when a user can receive downlink data, an MME (Mobility Management Entity) packages the cached short messages to the user, and when the user cannot receive the downlink data, the MME caches the short messages that need to be sent to the user, and when the user can receive the downlink data, packages the short messages to the user.

In the prior art, when a user moves across MMEs, since there is no mechanism for transmitting short messages between the MME connected before the user moves across MMEs and the MME connected after the user moves across MMEs in the prior art, the situation that cached short messages are lost is caused, so that the reliability of short message transmission is greatly reduced.

In summary, in the existing NB-IoT short message service, there is a problem that the short message that is moved across the MME by the user and is easy to lose the cache is generated, thereby causing poor reliability of short message transmission.

Disclosure of Invention

The invention provides a method and equipment for transmitting short messages, which are used for solving the problems that cached short messages are easily lost when a user moves across MME and the short message transmission reliability is poor in the prior art.

The embodiment of the invention provides a method for transmitting short messages, which comprises the following steps:

the first MME determines that the terminal moves across MME;

the first MME sends the short message session message corresponding to the terminal to a second MME corresponding to the terminal after the terminal moves in a TAU (Tracking Area Update) process of the terminal, or sends the short message session message corresponding to the terminal to a first service gateway corresponding to the terminal after the terminal moves.

after a terminal moves across MME, a second MME determines a corresponding first MME before the terminal moves;

the second MME receives a short message session message sent by a corresponding first MME before the terminal moves in the TAU process of the terminal which moves across MME, or receives a short message session message sent by a first service gateway after the TAU process of the terminal;

and the second MME sends the short message session message to the terminal after the TAU of the terminal is successful.

a first service gateway receives a short message session message sent by a corresponding first MME before the terminal moves after a TAU process of the terminal moving across MMEs occurs;

and the first service gateway sends the short message session message to the terminal through a base station.

after a TAU process of a terminal moving across MME occurs, a second service gateway receives a short message session message of a corresponding first MME before the terminal moves;

and the second service gateway sends the short message session message to the first service gateway after the terminal moves.

The embodiment of the invention provides a first MME for transmitting short messages, which comprises: a processor and a transceiver:

the processor is used for transmitting data through the transceiver and determining that the terminal moves across the MME; and sending the short message session message corresponding to the terminal to a second MME corresponding to the mobile terminal after the terminal moves in the TAU process of the terminal, or sending the short message session message corresponding to the terminal to a first service gateway corresponding to the mobile terminal after the TAU process.

The embodiment of the invention provides a second MME for transmitting short messages, which comprises: a processor and a transceiver:

the processor is used for transmitting data through the transceiver and determining a corresponding first MME before the terminal moves after the terminal moves across MME; receiving a short message session message sent by a corresponding first MME before the terminal moves in a TAU process of the terminal which moves across MME, or receiving a short message session message sent by a first service gateway after the TAU process of the terminal; and after the TAU of the terminal is successful, sending the short message session message to the terminal.

The embodiment of the invention provides a first service gateway for transmitting short messages, which comprises: a processor and a transceiver:

the processor is used for transmitting data through the transceiver and receiving a short message session message sent by a corresponding first MME before the terminal moves after a TAU process of the terminal moving across MMEs occurs; and sending the short message session message to the terminal through the base station.

The embodiment of the invention provides a second service gateway for transmitting short messages, which comprises: a processor and a transceiver:

the processor is used for transmitting data through the transceiver and receiving a short message session message of a corresponding first MME before the terminal moves after a TAU process of the terminal moving across MME occurs; and sending the short message session message to the first service gateway after the terminal moves.

The embodiment of the invention provides a first MME for transmitting short messages, which comprises:

at least one processing unit and at least one memory unit, wherein the memory unit stores program code that, when executed by the processing unit, causes the processing unit to perform the following:

determining that the terminal moves across MME; and sending the short message session message corresponding to the terminal to a second MME corresponding to the mobile terminal after the terminal moves in the TAU process of the terminal, or sending the short message session message corresponding to the terminal to a first service gateway corresponding to the mobile terminal after the TAU process.

The embodiment of the invention provides a second MME for transmitting short messages, which comprises:

after a terminal moves across MME, determining a corresponding first MME before the terminal moves; receiving a short message session message sent by a corresponding first MME before the terminal moves in a TAU process of the terminal which moves across MME, or receiving a short message session message sent by a first service gateway after the TAU process of the terminal; and after the TAU of the terminal is successful, sending the short message session message to the terminal.

The embodiment of the invention provides a first service gateway for transmitting short messages, which comprises:

receiving a short message session message sent by a corresponding first MME before the terminal moves after a TAU process of the terminal moving across MMEs occurs; and sending the short message session message to the terminal through the base station.

The embodiment of the invention provides a second service gateway for transmitting short messages, which comprises:

after a TAU process of a terminal moving across MME occurs, receiving a short message session message of a corresponding first MME before the terminal moves; and sending the short message session message to the first service gateway after the terminal moves.

A computer-storable medium on which a computer program is stored which, when being executed by a processor, carries out the steps of the above-mentioned method.

In the embodiment of the invention, after the terminal moves across the MME, the MME connected before the terminal moves across the MME sends the cached short message to the MME connected after the terminal moves across the MME in the TAU process of the terminal, so that the short message session message cached in the MME connected originally can not be lost after the position of the terminal changes and enters a new MME; in addition, in the connected state, after the terminal TAU process, the short message session message cached in the MME before the terminal moves across the MME can be forwarded by different service gateways connected before and after the terminal moves across the MME, and finally the cached short message session message is transmitted to the network system where the terminal is located currently, so that the short message session message cached in the MME connected before the terminal moves is prevented from being lost, and the reliability of the short message service of the internet of things is improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

Fig. 1 is a system for transmitting a short message according to a first embodiment of the present invention;

fig. 2 is a system for transmitting a second short message according to an embodiment of the present invention;

fig. 3 is a system for transmitting a third short message according to an embodiment of the present invention;

fig. 4 is a detailed flowchart corresponding to the method for transmitting a short message through context response between MMEs connected before and after a terminal moves across MMEs according to the embodiment of the present invention;

fig. 5 is a detailed flowchart corresponding to the method for transmitting a short message in which a terminal does not change across serving gateways before and after an MME movement according to the embodiment of the present invention;

fig. 6 is a detailed flowchart corresponding to the method for transmitting a short message through an indirect forwarding tunnel according to the embodiment of the present invention;

fig. 7 is a flowchart illustrating a first short message transmission method according to an embodiment of the present invention;

fig. 8 is a flowchart illustrating a second short message transmission method according to an embodiment of the present invention;

fig. 9 is a flowchart illustrating a third method for transmitting a short message according to an embodiment of the present invention;

fig. 10 is a flowchart illustrating a fourth method for transmitting a short message according to an embodiment of the present invention;

fig. 11 is a schematic structural diagram of a first MME for transmitting a first short message according to an embodiment of the present invention;

fig. 12 is a schematic structural diagram of a second MME for transmitting a first short message according to an embodiment of the present invention;

fig. 13 is a schematic structural diagram of a first service gateway for transmitting a first short message according to an embodiment of the present invention;

fig. 14 is a schematic structural diagram of a second service gateway for transmitting a first short message according to an embodiment of the present invention;

fig. 15 is a schematic structural diagram of a first MME for transmitting a second short message according to an embodiment of the present invention;

fig. 16 is a schematic structural diagram of two MMEs for transmitting a second short message according to an embodiment of the present invention;

fig. 17 is a schematic structural diagram of a first service gateway for transmitting a second short message according to an embodiment of the present invention;

fig. 18 is a schematic structural diagram of a second service gateway for transmitting a second short message according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings, and it is apparent that the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The embodiment of the invention is provided for two special energy-saving modes of PSM and eDRX in NB-IoT.

The NB-IoT technology adopts an ultra-narrow band (200kHz) and low-cost design, sacrifices rate and time delay and obtains more extreme bearing capacity of the Internet of things. Meanwhile, the terminal and the network are greatly simplified, the industrial development period is shortened, and the difficulty is reduced. Meanwhile, the NB-IoT system is also a new technology and system (only based on FDD (Frequency Division Duplex) mode) specially designed for low-power-consumption and wide-coverage internet of things services.

The NB-IoT technology optimizes the core network, not only adopts the lightweight core network, optimizes the end-to-end flow, simplifies the protocol stack, carries data and charging mode, but also supports new energy-saving modes, namely PSM and eDRX.

The PSM is an energy-saving mode in NB-IoT, in which the terminal radio frequency is turned off, which is equivalent to a power-off state, but the core network side also retains the user context data to facilitate the next session recovery. When the PSM state is in, the downlink is not reachable, and after the downlink data instruction reaches the MME, the MME informs an S-GW (Serving GateWay) to cache the downlink data of the user and delay the triggering paging; when data or signaling needs to be sent in the uplink, the terminal is triggered to enter a connection state.

The eDRX is another energy-saving mode for NB-IoT, and according to the characteristic that the downlink data transmission frequency of a user is low, through negotiation cooperation between a core network and a terminal, the terminal skips most paging monitoring, so that the purpose of saving power can be achieved.

When a user moves from one tracking area to another, the location registration must be performed again on the new tracking area to inform the network to change the location information of the user stored in the new tracking area, which is called TAU.

The connection state of the terminal can be divided into a connection state and an idle state, and when the terminal is in different connection states, the adopted scheme of MME short message caching is different.

Firstly, the terminal is in an idle state.

As shown in fig. 1, the present invention provides a system for transmitting a short message, including:

a first MME100, configured to determine that a terminal moves across MMEs; sending the short message session message corresponding to the terminal to a second MME corresponding to the mobile terminal after the terminal moves in the TAU process of the terminal;

the second MME101 is used for determining a corresponding first MME before the terminal moves after the terminal moves across MME; receiving a short message session message sent by the first MME corresponding to the terminal before moving in the TAU process of the terminal moving across MME; and after the TAU of the terminal is successful, sending the short message session message to the terminal.

The first MME refers to an MME connected before the terminal crosses the MME and moves, and the second MME refers to an MME connected after the terminal crosses the MME and moves.

When the terminal is in an idle state, two situations can be further divided according to whether a serving gateway connected to the terminal changes after the terminal moves across the MME.

1. The terminal which moves across the MME currently is in an idle state, and a service gateway connected with the terminal is changed, at the moment, the short message caching of the MME is short message session messages which are transmitted by the context response between the MME connected before and after the terminal moves across the MME in the TAU process of the terminal, and the MME caching is connected before the terminal moves across the MME.

When short message transmission is implemented in the TAU flow of the terminal, the first MME connected before the terminal moves across MMEs is first confirmed.

Optionally, the first MME determines that the terminal moves across MMEs.

Correspondingly, after the terminal moves across the MME, the second MME determines the corresponding first MME before the terminal moves.

In specific implementation, the terminal is performing a periodic TAU due to a change in location, in this process, the terminal sends a TAU request message to a second MME currently connected through a connected base station, and the TAU request message includes GUTI (Globally Unique Temporary User Equipment Identity) information, and then the second MME analyzes the obtained GUTI information to obtain information of the first MME, and determines the first MME connected before the terminal moves across MMEs.

The GUTI information mainly includes UE (User Equipment) identity information, identity information of an MME before the UE moves across the MMEs, and the like, and is used to determine the MME connected before the terminal moves across the MMEs.

At this time, the short message to be sent to the terminal is not cached in the MME connected after the terminal moves.

After determining the identity information of the first MME, the second MME asks the first MME for the information of the user and the cached short message session message which should be sent to the terminal through the TAU process of the terminal.

Optionally, the first MME sends the short message session message corresponding to the terminal to the second MME corresponding to the terminal after the terminal moves through the context response message in the TAU process of the terminal.

Correspondingly, the second MME receives the short message session message corresponding to the terminal sent by the first MME through the context response message in the TAU process of the terminal.

In a specific implementation, when the terminal moves, the terminal triggers a TAU procedure. And then, the second MME requests the short message session message which is stored in the first MME and is to be sent to the terminal from the first MME in the context response instruction. And then, the first MME sends the short message session message which is cached by the first MME and is to be sent to the terminal to the second MME through the context response message in the TAU process of the terminal.

Therefore, the short message session message data originally cached on the first MME is cached on the second MME which is currently connected with the terminal, and when the terminal moves across the MMEs, the short message session message cached on the MME which is connected with the terminal before the terminal moves across the MMEs can not be lost due to the change of the MME connected with the terminal.

And after the second MME receives the short message session data which is sent by the first MME and cached on the MME connected before the terminal moves across the MME, the second MME sends the cached short message session message to the terminal when a proper condition is met.

Optionally, after the TAU of the terminal is successful, the second MME sends the short message session message to the terminal through the base station.

And after the TAU process of the terminal is successfully completed, the second MME sends the received short message session message to the terminal. Therefore, after the terminal moves across the MME, the short message session message originally cached in the first MME can be cached in the second MME through the TAU process of the terminal, and after the terminal successfully completes the TAU process, the short message session message cached in the second MME is sent to the terminal. The short message session message originally cached in the MME connected before the terminal moves across the MME is successfully sent to the terminal, the cached short message session message is not lost, the short message service function of the narrowband Internet of things is improved, and the user experience is improved.

Fig. 4 shows a detailed flow of the method for transmitting a short message according to the present invention when the terminal is in an idle state and the serving gateway is changed.

2. The terminal which moves across the MME currently is in an idle state, and meanwhile, the S-GW connected with the terminal is not changed, and at the moment, the short message session message cached in the MME short message cache is transmitted through context response messages between the MMEs connected before and after the terminal moves across the MME in the terminal TAU process.

Firstly, a second MME connected after the terminal moves across the MMEs determines a first MME connected before the terminal moves across the MMEs according to information obtained in the TAU process of the terminal.

Optionally, the first MME determines that the terminal moves across MMEs.

When the terminal moves, a trigger of a TAU process of the terminal is started, the terminal sends a TAU request message to a base station, and further sends the TAU request message to a currently connected MME, wherein the TAU request message contains GUTI information, and a second MME obtains information of a first MME connected before the terminal moves across MME from the GUTI information, so that the first MME connected before the terminal moves across MME is confirmed, and the cached short message session message is transmitted continuously.

After the first MME connected before the terminal moves across the MMEs is determined, the transmission of the cached short message conversation messages is carried out between the first MME and the second MME.

In the TAU process of the terminal, the second MME sends a context request message to the first MME, requires information of a user and a cached short message session message to be sent to the terminal, and then the first MME feeds back data information required by the second MME to the second MME along with a context response message. Therefore, the first MME transmits the short message session message which needs to be sent to the terminal to the second MME connected after the terminal moves across the MMEs completely, and the cached short message session message is cached to the second MME connected with the current terminal along with the movement of the terminal, so that the loss of the cached short message session message is avoided.

And when the conditions are appropriate, the second MME sends the cached short message conversation message to the base stations, and then the short message conversation message is sent to the terminal by the base stations.

And after the terminal successfully completes the TAU process, the second MME sends the cached short message session message to the base station, and then the short message session message is sent to the terminal by the base station. The terminal successfully receives the short message session message cached in the first MME, so that the reliability of the short message service of the narrowband Internet of things is improved, and the user experience is better.

Please refer to fig. 5 for details of the method for transmitting short messages provided by the present invention when the terminal is in an idle state and the serving gateway is not changed.

And secondly, the terminal is in a connection state.

When the terminal is in the connected state, two situations can be further divided according to whether the serving gateway connected after the terminal moves across the MME changes.

1. The terminal has different service gateways connected before and after moving across the MME, and under the state, the embodiment of the invention provides three solutions.

The first scheme is as follows: and transmitting the cached short message session message through the context response in the TAU process of the terminal.

Specifically, the first MME determines that the terminal moves across MME; sending the short message session message corresponding to the terminal to a second MME corresponding to the mobile terminal after the terminal moves in the TAU process of the terminal;

after a terminal moves across MME, a second MME determines a corresponding first MME before the terminal moves; receiving a short message session message sent by the first MME corresponding to the terminal before moving in the TAU process of the terminal moving across MME; and after the TAU of the terminal is successful, sending the short message session message to the terminal.

The present solution is explained below in terms of steps.

Optionally, the first MME determines that the terminal moves across MMEs.

Firstly, the second MME determines the first MME after the terminal moves across the MMEs from the first MME through a TAU request message of a terminal TAU process. And the second MME sends a context request message to the first MME, and asks for the information of the terminal and the short message session message cached in the first MME. So as to transmit the cached SMS session message subsequently.

And after the first MME receives the context request message sent by the second MME, the first MME feeds back a context response message to the second MME.

Optionally, the first MME sends the short message session message corresponding to the terminal to the second MME corresponding to the terminal after the terminal moves through the context response message in the TAU process of the terminal

In the implementation, a second MME connected after the terminal moves across the MME requests a first MME connected before the terminal moves across the MME to request information of the terminal and short message session information cached in the first MME through a context request in a terminal TAU process; and after receiving the request, the first MME transmits the information requested by the second MME to the second MME by the context response in the TAU process of the terminal.

At this time, the short message session messages cached in the original first MME are all transferred to a second MME which can be connected with the user, so that the short message session messages can be sent to the terminal subsequently.

Optionally, after the TAU of the terminal is successfully completed, the second MME sends the short message session message to the terminal through the base station.

And after the terminal successfully completes the TAU process, the second MME sends the cached short message session message to the base station, and then the short message session message is sent to the terminal by the base station.

Therefore, the issuing task of the short message session message cached in the first MME connected before the terminal moves across the MMEs is completed, the short message session message cached in the first MME is not lost, the terminal successfully receives the cached short message session message, the reliability of the short message service of the narrow-band Internet of things is improved, and the user experience is better.

Please refer to fig. 4 for details of the method for transmitting short messages provided by the present invention when the terminal is in a connected state and the serving gateway changes.

Scheme II: the first MME transmits the cached short message session message to the first service gateway through the established indirect forwarding tunnel, and the first service gateway directly sends the short message session message to the terminal.

Specifically, as shown in fig. 2, the present invention provides a system for transmitting a short message, where the system includes:

the first MME200 is configured to send the short message session message corresponding to the terminal to a first service gateway corresponding to the mobile terminal;

a first service gateway 201, configured to receive, after a TAU procedure of a terminal moving across MMEs occurs, a short message session message sent by a corresponding first MME before the terminal moves; sending the short message session message to the terminal;

the second serving gateway 202 is configured to receive, after a TAU procedure of a terminal moving across MMEs occurs, a short message session message of a corresponding first MME before the terminal moves; and sending the short message session message to the first service gateway after the terminal moves.

Optionally, the first MME sends the short message session message corresponding to the terminal to the second serving gateway through an S11 interface or an S11-U interface.

Correspondingly, after the TAU process of the terminal moving across the MME occurs, the second service gateway receives the short message session message of the corresponding first MME before the terminal moves.

In the scheme, the terminal firstly completes the TAU process of the terminal, and then after the indirect forwarding tunnel is established, the first MME transmits the cached short message session message to the second serving gateway through the S11 interface or the S11-U interface by modifying the bearer request message.

At this time, the short message session message buffered in the first MME is transferred to the second serving gateway, so as to facilitate subsequent transmission through the indirect forwarding tunnel.

Optionally, the second service gateway sends the short message session message to the first service gateway after the terminal moves through an indirect forwarding tunnel.

Correspondingly, the first serving gateway receives, through an indirect forwarding tunnel, the short message session message from the first MME, which is sent by the second serving gateway, after the TAU procedure of the terminal.

After the short message session message cached in the first MME is transferred to the second service gateway, the second service gateway transfers the cached short message session message transferred by the first MME to the first service gateway through the indirect transfer tunnel established earlier. And when the first service gateway receives the short message session message transmitted by the second service gateway, waiting for a proper network condition, and transmitting the cached short message session message to the terminal by the first service gateway.

Optionally, the first service gateway sends the short message session message to the terminal through a base station.

When the current terminal is in a connected state, after the first service gateway receives the short message session message which is transmitted by the second service gateway and cached before the terminal moves across the MME, the obtained short message session message is sent to the base station, and then the short message session message is sent to the terminal by the base station.

Therefore, the short message session message cached before the terminal moves across the MME is successfully sent to the terminal without being lost, the reliability of the short message service of the narrow-band Internet of things is improved, and the user experience is better.

In the method, the transmission of the short message session message cached in the first MME to the first serving gateway is performed after the TAU process of the terminal is successfully completed.

Please refer to fig. 5 for details of the method for transmitting short messages provided by the present invention when the terminal is in a connected state and the serving gateway changes.

The third scheme is as follows: and the first MME transmits the cached short message session message to the second MME through the established indirect forwarding tunnel, and the second MME sends the short message session message to the terminal.

Specifically, as shown in fig. 3, the present invention provides a system for transmitting a short message, where the system includes:

the first MME300 is configured to send the short message session message corresponding to the terminal to a first service gateway corresponding to the mobile terminal after the TAU procedure;

the second MME301 is configured to receive, after the TAU procedure of the terminal, a short message session message sent by the first serving gateway; after the TAU of the terminal is successful, the short message session message is sent to the terminal;

a first serving gateway 302, configured to receive, after a TAU procedure of a terminal moving across MMEs occurs, a short message session message sent by a corresponding first MME before the terminal moves;

the second serving gateway 303 is configured to receive, after a TAU procedure of a terminal moving across MMEs occurs, a short message session message of a corresponding first MME before the terminal moves; and sending the short message session message to the first service gateway after the terminal moves.

In a specific implementation, after the TAU procedure of the terminal is successfully completed, an indirect forwarding tunnel is established, and then, the first MME transmits the cached short message session message to the second serving gateway through modifying the bearer request message by the S11 interface or the S11-U interface.

After the short message session message cached in the first MME is transferred to the second service gateway, the second service gateway transfers the cached short message session message transferred by the first MME to the first service gateway through the indirect transfer tunnel established earlier. When the first serving gateway receives the short message session message transmitted by the second serving gateway, the short message session message originally cached in the first MME is already transferred to the first serving gateway, and further, the first serving gateway transmits the cached short message session message to the second MME.

Optionally, the second MME receives a short message session message sent by the first serving gateway after the TAU procedure of the terminal; and sending the short message session message to the terminal through the base station.

When the first service gateway sends the cached short message session message to the second MME, the second MME receives the cached short message session message, and because the current terminal is in a connection state, the second MME sends the short message session message to the base station, and then the base station sends the short message session message to the terminal. Therefore, after the short message session message cached before the terminal moves across the MME passes through the transmission among the first MME, the second service gateway, the first service gateway and the second MME, the second MME finally sends the short message session message to the base station, and then the base station sends the short message session message to the terminal, so that the condition that the short message session message cached in the first MME is lost due to the movement of the terminal across the MME is avoided, the reliability of the short message service in the narrowband Internet of things is improved, and the user experience is improved.

Please refer to fig. 6 for details of the method for transmitting short messages provided by the present invention when the terminal is in a connected state and the serving gateway changes.

2. The serving gateways connected before and after the terminal moves across the MME are the same.

At this time, the buffered sms can be transmitted through the context response in the terminal TAU procedure.

Optionally, the first MME determines that the terminal moves across MMEs.

Before the MME short message transfer, firstly, the second MME determines that the terminal is behind the first MME before the MME moves through the TAU request message in the terminal TAU process. And the second MME sends a context request message to the first MME, and asks the first MME for the information of the terminal and the short message session message stored in the first MME so as to transmit the short message session message stored in the first MME subsequently.

Then, after the terminal moves across the MME, the second MME requests the first MME before the terminal moves across the MME for the information of the terminal and the short message session message cached in the first MME through the context request in the TAU process of the terminal; and after receiving the request, the first MME transmits the information requested by the second MME to the second MME through context response in the TAU process of the terminal.

Therefore, the short message session message originally cached in the first MME is already stored in the second MME which can perform data transmission with the terminal, and then when the condition is met, the second MME sends the cached short message session message to the terminal.

And finally, after the TAU of the terminal is successfully completed, the second MME sends the cached short message session message to the base station, and then the short message session message is sent to the terminal by the base station.

In the embodiment of the invention, when the terminal performs the TAU process, the short message session message cached in the MME connected before the terminal moves is transferred to the second MME through the transmission of the context signaling between the first MME and the second MME, and then the second MME forwards the cached short message session message to the base station, and further transmits the message to the terminal, so that after the terminal moves across MMEs, the short message session message cached in the MME connected before the terminal moves across MMEs is not lost, thereby improving the reliability of the short message service of the narrowband internet of things, and improving the user experience.

Please refer to fig. 5 for details of the method for transmitting short messages provided by the present invention when the terminal is in a connected state and the serving gateway is not changed.

The method for transmitting the short message will be described in detail below.

As shown in fig. 4, a detailed flow chart of data transmission through context response between the first MME and the second MME in the present invention, in which the S-GW is also transformed.

Step 400, the UE triggers a TAU procedure (Trigger to start TAU procedure);

step 401, UE sends TAU Request message (TAU Request) to eNode (evolved base station);

step 402, the eNodeB sends a TAU Request message (TAU Request) to the new MME;

step 403, the new MME sends a Context Request message to the old MME, asking for information of the UE and a cached short message session message (Context Request);

step 404, the old MME sends a Context Response message to the new MME, where the message includes a short message session message (Context Response) cached by the old MME;

step 405, the new MME performs Authentication/Security (Authentication/Security) for the UE;

step 406, the new MME sends a Context verification message (Context acknowledgement) to the UE authentication rule;

step 407, the new MME sends a Create Session Request message (Create Session Request) to the new S-GW;

step 408, the new S-GW sends a Modify Bearer Request message (Modify Bearer Request) to the P-GW (Public Data Network Gateway);

step 409, performing PCEF Initiated IP-CAN (IP-Connectivity Access Network) Session Modification (PCEF Initiated IP-CAN Session Modification) between the P-GW and the PCRF (Policy and Charging Enforcement Function);

step 410, the P-GW sends a Modify Bearer Response message (Modify Bearer Response) to the new S-GW;

step 411, the new S-GW sends Create Session request Response message (Create Session Response) to the new MME;

step 412, the new MME sends a Location Update message (Update Location) to the HSS (Home Subscriber Server);

step 413, the HSS sends a Cancel Location request message (Cancel Location) to the old MME;

step 414, the old MME sends a Cancel Location response message (Cancel Location Ack) to the HSS;

step 415, the RNC (Radio Network Controller ) sends a path Release request message (Iu Release Command) to the old MME;

step 416, the old MME sends a path Release Complete response message (Iu Release Complete) to the RNC;

step 417, the HSS sends a Location Update response message (Update Location Ack) to the new MME;

step 418, the old MME sends a Delete Session Request message (Delete Session Request) to the old S-GW;

step 419, the old S-GW sends a Delete Session Response message (Delete Session Response) to the old MME;

step 420, the UE sends a tracking area update receive message (TAU Accept) to the new MME;

in step 421, the new MME sends a tracking area update Complete message (TAU Complete) to the UE.

As shown in fig. 5, a detailed flowchart of data transmission through context response between the old and new MMEs in the present invention, wherein the S-GW is not changed.

Step 500, the UE triggers a TAU procedure (Trigger to start TAU procedure);

step 501, the UE sends a TAU Request message (TAU Request) to the eNodeB;

step 502, the eNodeB sends a TAU Request message (TAU Request) to the new MME;

step 503, the new MME sends a Context Request message to the old MME, asking for information of the UE and a cached short message session message (Context Request);

step 504, the old MME sends a Context Response message to the new MME, where the message includes a short message session message (Context Response) cached by the old MME;

step 505, the new MME performs Authentication/Security (Authentication/Security) for the UE;

step 506, the new MME sends a Context authentication message (Context acknowledgement) to the old MME;

step 507, the new MME sends a modify bearer Request message (Create Session Request) to the S-GW;

step 508, the S-GW sends Modify Bearer Request message (Modify Bearer Request) to the P-GW;

step 509, the P-GW performs PCEF Initiated IP-CAN Session Modification (PCEF Initiated IP-CAN Session Modification) with the PCEF;

step 510, the P-GW sends a Modify Bearer Response message (Modify Bearer Response) to the S-GW;

step 511, the S-GW sends a modify bearer Response message (Create Session Response) to the new MME;

step 512, the new MME sends a Location Update message (Update Location) to the HSS;

step 513, the HSS sends a Cancel Location request message (Cancel Location) to the old MME;

step 514, the old MME sends a Cancel Location response message (Cancel Location Ack) to the HSS;

step 515, the RNC sends a path Release request message (Iu Release Command) to the old MME;

step 516, the old MME sends a path Release Complete response message (Iu Release Complete) to the RNC;

step 517, the HSS sends a Location Update response message (Update Location Ack) to the new MME;

step 518, the UE sends a tracking area update receive message (TAU Accept) to the new MME;

in step 519, the new MME sends a tracking area update Complete message (TAU Complete) to the UE.

As shown in fig. 6, a detailed flow chart of data transmission through an indirect forwarding tunnel after the terminal TAU procedure in the present invention, in which the S-GW also changes.

Step 600, the UE triggers a TAU procedure (Trigger to start TAU procedure);

step 601, the UE sends a TAU Request message (TAU Request) to the eNodeB;

step 602, the eNodeB sends a TAU Request message (TAU Request) to the new MME;

step 603, the new MME sends a Context Request message (Context Request) to the old MME;

step 604, the old MME sends a Context Response message (Context Response) to the new MME;

step 605, the new MME performs Authentication/Security (Authentication/Security) for the UE;

step 606, the new MME sends Create Session Request message (Create Session Request) to the new S-GW;

step 607, the new S-GW modifies the Bearer Request message (Modify Bearer Request) to the P-GW;

step 608, performing PCEF Initiated IP-CAN Session Modification (PCEF Initiated IP-CAN Session Modification) between the P-GW and the PCEF;

step 609, the P-GW sends a Modify Bearer Response message (Modify Bearer Response) to the new S-GW;

step 610, the new S-GW sends a create session request response message (Update Location) to the new MME;

step 611, the UE sends a tracking area update receive message (TAU Accept) to the new MME;

step 612, the new MME sends a tracking area update Complete message (TAU Complete) to the UE;

step 613, the new MME sends an Initial Context Setup Request message (Initial Context Setup Request) to the base station;

step 614, the eNodeB sends an Initial Context Setup response message (Initial Context Setup Complete) to the new MME;

step 615, the new MME sends a Modify Bearer Request message (Modify Bearer Request) to the new S-GW;

step 616, the new S-GW sends a Modify Bearer Response message (Modify Bearer Response) to the new MME;

step 617, the new MME sends a Create Indirect Forwarding Tunnel request message (Create Indirect Forwarding Tunnel Response) to the new S-GW;

step 618, the new S-GW sends a response message (Forwarding F-TEID, Forwarding indication) to create the indirect Forwarding tunnel to the new MME;

step 619, the new MME sends a Context verification message to the old MME, and at this time, the new MME sends F-TEID (Full Qualified, Full tunnel endpoint flag) and Forwarding indication (Context acknowledgement) of data Forwarding to the old MME;

step 620, the old MME sends a Modify Bearer Request message (Modify Bearer Request) to the old S-GW;

step 621, the old S-GW sends a Modify Bearer Response message (Modify Bearer Response) to the old MME;

step 622, the old S-GW sends the downlink data buffered for transmission to the new S-GW, the new S-GW sends the downlink data buffered for transmission to the base station, and then the base station sends the downlink data buffered for transmission (Forwarding of DL data) to the UE;

step 623, the new MME sends a Location Update message (Update Location) to the HSS;

step 624, the HSS sends a Cancel Location request message (Cancel Location) to the old MME;

step 625, the old MME sends a Cancel Location response message (Cancel Location Ack) to the HSS;

step 626, the RNC sends a path Release request message (Iu Release Command) to the old MME;

step 627, the old MME sends a path Release Complete response message (Iu Release Complete) to the RNC;

step 628, the old MME sends a Delete Session Request message (Delete Session Request) to the old S-GW;

step 629, the old S-GW sends Delete Session Response message (Delete Session Response) to the old MME;

step 630, the HSS sends a Location Update response message (Update Location Ack) to the new MME;

step 631, the new MME sends a Delete Indirect Forwarding Tunnel Request message (Delete Indirect Forwarding Tunnel Request) to the new S-GW;

in step 632, the new S-GW sends a Delete Indirect Forwarding Tunnel Response message (Delete Indirect Forwarding Tunnel Response) to the new MME.

If the UE uses user plane transmission, the UE establishes a bearer context between the new MME and the old S-GW in steps 613 to 616, and if the UE uses control plane transmission, step 613 to step 616 are omitted.

In fig. 4, 5, and 6, the new MME refers to a second MME connected after the terminal moves across MMEs, the old MME refers to a first MME connected before the terminal moves across MMEs, the new S-GW refers to a first S-GW connected after the terminal moves across MMEs, and the old S-GW refers to a second S-GW connected before the terminal moves across MMEs.

In the embodiment of the invention, if the terminal is connected with the S4-SGSN before crossing the MME, the first MME in the embodiment of the invention can be replaced by the S4-SGSN of the terminal which is connected before crossing the MME.

Based on the same inventive concept, the embodiment of the present invention further provides a method for transmitting a short message, and because the devices corresponding to the method are the first MME, the second MME, the first S-GW, and the second S-GW in the embodiment of the present invention, and the principle of the method for solving the problem is similar to that of the system, the method can be implemented with reference to the system, and repeated parts are not described again.

As shown in fig. 7, the present invention provides a method for transmitting a short message, including:

step 700, the first MME determines that the terminal moves across MME;

step 701, the first MME sends the short message session message corresponding to the terminal to a second MME corresponding to the terminal after the terminal moves in the TAU process of the terminal, or sends the short message session message corresponding to the terminal to a first service gateway corresponding to the terminal after the terminal moves in the TAU process.

Optionally, when the first MME sends the short message session message corresponding to the terminal to the second MME in the TAU process of the terminal, the first MME sends the short message session message corresponding to the terminal to the second MME through the context response message in the TAU process of the terminal.

Optionally, when the first MME sends the short message session message TAU corresponding to the terminal to the first serving gateway corresponding to the terminal after moving, the first MME sends the short message session message corresponding to the terminal to the second serving gateway through the S11 interface or the S11-U interface, so that the second serving gateway sends the short message session message to the first serving gateway through the indirect forwarding tunnel.

As shown in fig. 8, the present invention provides a method for transmitting a short message, including:

step 800, after a second MME moves across MME, a first MME corresponding to the terminal before moving is determined by the second MME;

step 801, the second MME receives a short message session message sent by a corresponding first MME before the terminal moves in a TAU process of the terminal moving across MMEs, or receives a short message session message sent by a first service gateway after the TAU process of the terminal;

step 802, the second MME sends the short message session message to the terminal after the TAU of the terminal is successful.

Optionally, when the second MME receives the short message session message sent by the corresponding first MME before the terminal moves in a TAU process of the terminal moving across MMEs, the second MME receives the short message session message sent by the first MME corresponding to the terminal through a context response message in the TAU process of the terminal.

Optionally, when the second MME receives the short message session message sent by the first serving gateway after the TAU procedure of the terminal, the second MME receives the short message session message corresponding to the terminal sent by the second serving gateway through the S11 interface or the S11-U interface after the TAU procedure of the terminal, where the short message session message corresponding to the terminal is sent to the first serving gateway by the second serving gateway through an indirect forwarding tunnel.

As shown in fig. 9, the present invention provides a method for transmitting a short message, which is characterized in that the method includes:

step 900, after a TAU process of a terminal moving across MMEs occurs, a first service gateway receives a short message session message sent by a corresponding first MME before the terminal moves;

step 901, the first service gateway sends the short message session message to the terminal through a base station.

Optionally, when the first serving gateway receives the short message session message sent by the first MME corresponding to the terminal before moving after the TAU procedure of the terminal moving across MMEs occurs, the first serving gateway receives the short message session message sent by the second serving gateway from the first MME through an indirect forwarding tunnel after the TAU procedure of the terminal.

Optionally, when the first service gateway sends the short message session message to the terminal, the first service gateway sends the short message session message to the terminal through a base station; or after the TAU of the terminal is successful, the second MME sends the short message session message to the terminal through the base station.

As shown in fig. 10, the present invention provides a method for transmitting a short message, which is characterized in that the method includes:

step 1000, after a terminal TAU process of a terminal moving across MME occurs, a second service gateway receives a short message session message of a corresponding first MME before the terminal moves;

step 1001, the second service gateway sends the short message session message to the first service gateway after the terminal moves.

Optionally, when the second service gateway sends the short message session message to the first service gateway after the terminal moves, the second service gateway sends the short message session message to the first service gateway after the terminal moves through an indirect forwarding tunnel.

As shown in fig. 11, the present invention provides a first MME for transmitting a short message, including: processor 1100 and transceiver 1101:

the processor 1100 is configured to perform data transmission through a transceiver and determine that a terminal moves across MMEs; and sending the short message session message corresponding to the terminal to a second MME corresponding to the mobile terminal after the terminal moves in the TAU process of the terminal, or sending the short message session message corresponding to the terminal to a first service gateway corresponding to the mobile terminal after the TAU process.

Optionally, the processor 1100 is specifically configured to:

and sending the short message session message corresponding to the terminal to the second MME through a context response message in the TAU process of the terminal.

Optionally, the processor 1100 is specifically configured to:

and sending the short message session message corresponding to the terminal to a second service gateway through an S11 interface or an S11-U interface so that the second service gateway sends the short message session message to the first service gateway through an indirect forwarding tunnel.

As shown in fig. 12, the present invention provides a second MME for transmitting a short message, including: processor 1200 and transceiver 1201:

the processor 1200 is configured to perform data transmission through the transceiver, and receive a short message session message sent by a first MME corresponding to a terminal before the terminal moves in a TAU procedure of the terminal that moves across MMEs, or receive a short message session message sent by a first service gateway after the TAU procedure of the terminal; and after the TAU of the terminal is successful, sending the short message session message to the terminal.

Optionally, the processor 1200 is specifically configured to:

when a short message session message sent by a first MME corresponding to a terminal before the terminal moves is received in a TAU process of the terminal moving across MME, the short message session message sent by the first MME corresponding to the terminal is received through a context response message in the TAU process of the terminal.

Optionally, the processor 1200 is specifically configured to:

and receiving a short message session message corresponding to the terminal, which is sent by a second service gateway, through an S11 interface or an S11-U interface after the TAU process of the terminal, wherein the short message session message corresponding to the terminal is sent to the first service gateway by the second service gateway through an indirect forwarding tunnel.

As shown in fig. 13, the present invention provides a first service gateway for transmitting a short message, including: processor 1300 and transceiver 1301:

Optionally, the processor 1300 is specifically configured to:

and receiving the short message session message from the first MME, which is sent by the second serving gateway, through an indirect forwarding tunnel after the TAU process of the terminal.

Optionally, the processor 1300 is specifically configured to:

sending the short message session message to the terminal through a base station; or after the short message session message is sent to the second MME, the short message session message is sent to the terminal through the base station.

As shown in fig. 14, the present invention provides a second service gateway for transmitting a short message, including: processor 1400 and transceiver 1401:

Optionally, the processor 1400 is specifically configured to:

and sending the short message session message to the first service gateway after the terminal moves through an indirect forwarding tunnel.

As shown in fig. 15, the present invention provides a first MME for transmitting a short message, where the first MME includes:

at least one processing unit 1500 and at least one storage unit 1501, wherein the storage unit stores program code that, when executed by the processing unit, causes the processing unit to perform the following:

Optionally, the processing unit 1500 is specifically configured to:

As shown in fig. 16, the present invention provides a second MME for transmitting a short message, where the second MME includes:

at least one processing unit 1600 and at least one storage unit 1601 unit, wherein the storage unit stores program code that, when executed by the processing unit, causes the processing unit to perform the following:

Optionally, the processing unit 1600 is specifically configured to:

As shown in fig. 17, the present invention provides a first service gateway for transmitting a short message, where the first service gateway includes:

at least one processing unit 1700 and at least one memory unit 1701, wherein the memory unit stores program code that, when executed by the processing unit, causes the processing unit to perform the following:

Optionally, the processing unit 1700 is specifically configured to:

As shown in fig. 18, the present invention provides a second service gateway for transmitting a short message, where the second service gateway includes:

at least one processing unit 1800 and at least one memory unit 1801, wherein said memory unit stores program code that, when executed by said processing unit, causes said processing unit to perform the following:

Optionally, the processing unit 1800 is specifically configured to:

A computer-readable medium, on which a computer program is stored, characterized in that the program realizes the steps as in fig. 7 or fig. 8 or fig. 9 or fig. 10 when executed by a processor.

The present application is described above with reference to block diagrams and/or flowchart illustrations of methods, apparatus (systems) and/or computer program products according to embodiments of the application. It will be understood that one block of the block diagrams and/or flowchart illustrations, and combinations of blocks in the block diagrams and/or flowchart illustrations, 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, and/or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer and/or other programmable data processing apparatus, create means for implementing the functions/acts specified in the block diagrams and/or flowchart block or blocks.

Accordingly, the subject application may also be embodied in hardware and/or in software (including firmware, resident software, micro-code, etc.). Furthermore, the present application may take the form of a computer program product on a computer-usable or computer-readable storage medium having computer-usable or computer-readable program code embodied in the medium for use by or in connection with an instruction execution system. In the context of this application, a computer-usable or computer-readable medium may be any medium that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A method for transmitting a short message, the method comprising:

a first Mobility Management Entity (MME) determines that a terminal moves across MMEs;

the first MME sends a short message session message corresponding to the terminal to a second MME corresponding to the mobile terminal after the terminal moves in the process of updating TAU in a tracking area of the terminal, or sends the short message session message corresponding to the terminal to a first service gateway corresponding to the mobile terminal after the TAU process;

the sending, by the first MME, the short message session message corresponding to the terminal to the second MME in a TAU procedure of the terminal includes:

the first MME sends a short message session message corresponding to the terminal to the second MME through a context response message in the TAU process of the terminal;

the first MME sending the short message session message TAU corresponding to the terminal to the first service gateway corresponding to the terminal after moving, including:

and the first MME sends the short message session message corresponding to the terminal to a second service gateway through an S11 interface or an S11-U interface, so that the second service gateway sends the short message session message to the first service gateway through an indirect forwarding tunnel.

2. A method for transmitting a short message, the method comprising:

the second MME sends the short message session message to the terminal after the TAU of the terminal is successful;

the second MME receives the short message session message sent by the corresponding first MME before the terminal moves in the TAU process of the terminal which moves across MMEs, and the method comprises the following steps:

the second MME receives a short message session message corresponding to the terminal sent by the first MME through a context response message in the TAU process of the terminal;

the second MME receiving, after the TAU procedure of the terminal, a short message session message sent by a first service gateway, including:

and the second MME receives a short message session message corresponding to the terminal, which is sent by a second service gateway, through an S11 interface or an S11-U interface after the TAU process of the terminal, wherein the short message session message corresponding to the terminal is sent to the first service gateway by the second service gateway through an indirect forwarding tunnel.

3. A method for transmitting a short message, the method comprising:

the first service gateway sends the short message session message to the terminal through a base station;

the method for receiving the short message session message sent by the first MME corresponding to the terminal before moving after the terminal moving across the MMEs occurs to the first service gateway in the TAU process includes the following steps:

and the first service gateway receives a short message session message from the first MME, which is sent by a second service gateway, through an indirect forwarding tunnel after the TAU process of the terminal.

4. The method of claim 3, wherein the first service gateway sending the SMS session message to the terminal comprises:

the first service gateway sends the short message session message to the terminal through a base station; or

And after the short message session message is sent to the second MME, the short message session message is sent to the terminal through the base station.

5. A method for transmitting a short message, the method comprising:

the second service gateway sends the short message session message to the first service gateway after the terminal moves;

the sending, by the second service gateway, the short message session message to the first service gateway after the terminal moves includes:

and the second service gateway sends the short message session message to the first service gateway after the terminal moves through an indirect forwarding tunnel.

6. A first MME for short message transmission, comprising: a processor and a transceiver:

the processor is used for transmitting data through the transceiver and determining that the terminal moves across the MME; sending the received short message session message corresponding to the terminal to a second MME corresponding to the mobile terminal after the terminal moves in the TAU process of the terminal, or sending the short message session message corresponding to the terminal to a first service gateway corresponding to the mobile terminal after the TAU process;

the processor is specifically configured to:

sending a short message session message corresponding to the terminal to the second MME through a context response message in the TAU process of the terminal;

the processor is specifically configured to:

7. A second MME for short message transmission, comprising: a processor and a transceiver:

the processor is used for transmitting data through the transceiver and determining a corresponding first MME before the terminal moves after the terminal moves across MME; receiving a short message session message sent by a corresponding first MME before the terminal moves in a TAU process of the terminal which moves across MME, or receiving a short message session message sent by a first service gateway after the TAU process of the terminal; after the TAU of the terminal is successful, the short message session message is sent to the terminal;

the processor is specifically configured to:

when a short message session message sent by a corresponding first MME before the terminal moves is received in the TAU process of the terminal moving across MME, the short message session message sent by the first MME and corresponding to the terminal is received through a context response message in the TAU process of the terminal;

the processor is specifically configured to:

8. A first service gateway for short message transmission, comprising: a processor and a transceiver:

the processor is used for transmitting data through the transceiver and receiving a short message session message sent by a corresponding first MME before the terminal moves after a TAU process of the terminal moving across MMEs occurs; sending the short message session message to the terminal through a base station;

the processor is specifically configured to:

and receiving the short message session message from the first MME, which is sent by a second service gateway, through an indirect forwarding tunnel after the TAU process of the terminal.

9. The first serving gateway of claim 8, wherein the processor is specifically configured to:

10. A second service gateway for short message transmission, comprising: a processor and a transceiver:

the processor is used for transmitting data through the transceiver and receiving a short message session message of a corresponding first MME before the terminal moves after a TAU process of the terminal moving across MME occurs; sending the short message session message to a first service gateway after the terminal moves;

the processor is specifically configured to:

11. An apparatus for short message transmission, comprising: at least one processing unit and at least one memory unit, wherein the memory unit stores program code which, when executed by the processing unit, causes the processing unit to perform the steps of the method of claim 1 or the steps of the method of claim 2 or the steps of the method of claim 3 or the steps of the method of claim 5.

12. A computer-readable medium, on which a computer program is stored which, when being executed by a processor, carries out the steps of the method as claimed in claim 1 or the steps of the method as claimed in claim 2 or the steps of the method as claimed in claim 3 or the steps of the method as claimed in claim 5.