CN102076032A - Method for deleting context of terminal and handover system for terminal - Google Patents

Abstract

The embodiment of the invention discloses a method for deleting the context of a terminal and a handover system for the terminal. The handover of the terminal from a source base station to a target base station is realized by the following steps that: the target base stations transmit switching data path logout messages to an anchor access service network gateway; after receiving the logout messages, the anchor access service network gateway transmits the switching data path logout messages to the source base station; and after receiving the switching data path logout messages and HO_Complete messages from all the target base stations, the source base station deletes the context of the terminal, wherein the target base stations comprise selected and unselected target base stations, and the selected target base station transmits the switching data path logout message to the anchor access service network gateway after confirming that the switching of the service flow data of the terminal is finished. The switching of the data is ensured to be finished and the normal release of a switching data path is ensured by selecting a correct time for deleting the context of the terminal.

Description

The method of deleting the terminal context and the system of terminal switching

technical field

The embodiment of the present invention relates to the technical field of communication, and specifically relates to a method for deleting a terminal context and a system for switching a terminal.

Background technique

WiMAX (Worldwide Interoperability for Microwave Access), the Chinese full name is global microwave access interoperability, is a wireless metropolitan area network technology based on the IEEE 802.16 standard. The WiMAX network is mainly composed of three parts: terminal (MS), access service network (ASN) including base station (BS) and access service network gateway (ASN-GW), and connection service network (CSN). The WiMAX system generally adopts a hard handover method during the handover process. In order to avoid data loss during the handover process, the WiMAX Forum introduced a data integrity solution in the NWG1.5 system. Whether to adopt a data integrity scheme and which data integrity scheme to adopt is based on the granularity of business flow. That is, through negotiation among entities, the data integrity scheme may be adopted only for one or some service flows of the terminal during handover, or the data integrity scheme may not be adopted for all service flows. One implementation of the data integrity solution is to connect the target access service network (T-ASN) and the anchor access service gateway (Anchor ASN-GW), the anchor access service gateway (Anchor ASN-GW) and the service access A data return channel from the serving base station (S-BS) to the target base station (T-BS) is established between the incoming service network (S-ASN), and the data buffered in the S-BS during the handover process is sent through this return channel to the T-BS, thereby ensuring the integrity of the data sent to the terminal.

Figure 1 is a schematic diagram of data return in the prior art, where

Path0 is: a general data channel between the serving ASN and the anchor ASN-GW when no handover occurs.

Path1 is: a return data channel between the target ASN and the anchor ASN-GW for data return during the handover.

Path2 is: a return data channel between the serving ASN and the anchor ASN-GW for data return during handover.

Path3 is: a general data channel between the target ASN and the anchor ASN-GW after the handover is completed.

Figure 2 is a flow chart of handover using data backhaul to ensure data integrity. The specific process is as follows:

Step1: The MS initiates a MOB_MSHO_REQ handover request message to the serving base station.

Step2: The serving base station initiates a HO_REQ handover request message to one or more target base stations.

Step3: (Optional) The target base station sends pre-registration messages of data channel 1 (for general data transfer) and data channel 1 (for data return during handover) to the anchor ASN-GW.

Step4: (Optional) The anchor ASN-GW sends a pre-registration message of data channel 2 (for data return during handover) to the serving base station.

Step5: The target base station sends a HO_RSP handover reply message to the serving base station.

Step6: The serving base station sends a MOB_BSHO_RSP handover reply message to the MS.

Step7: The serving base station sends a HO_ACK handover confirmation message to the target base station.

Step8: The MS sends a MOB_HO_IND message to the serving base station, and enters the handover execution stage.

Step9: The serving base station sends a HO_Cnf message to the selected target base station. Optionally, the serving base station sends a HO_Cnf message to unselected target base stations, which carries a cancel handover cancellation instruction.

Step 10: The target base station sends a HO_ACK handover confirmation message to the serving base station. If the data channels 1 and 2 have been pre-registered, the serving base station can start to transmit data back to the target base station at this time.

Step11: (Optional) If Step3 is not executed, the target base station sends pre-registration messages of data channel 1 (for general data transfer) and data channel 1 (for data return during handover) to the anchor ASN-GW .

Step12: (Optional) If Step4 is not executed, the anchor ASN-GW sends a pre-registration message of data channel 2 (for data return during handover) to the serving base station.

Step13: The MS accesses the network at the selected target base station. After successfully accessing the network, the target base station starts to send the data cached in the Data Integrity Buffer (Data Integrity Buffer) to the MS.

Step 14: The target base station initiates a registration process of data channel 3 (general data channel) to the anchor ASN-GW.

Step 15: (Optional) If Step 3 or Step 11 is not executed, the target base station sends the advance data channel 1 (for general data transfer) and data channel 1 (for data return during handover) to the anchor ASN-GW. Sign up for messages.

Step 16: (Optional) If Step 4 or Step 12 is not executed, the anchor ASN-GW sends a pre-registration message of data channel 2 (for data return during handover) to the serving base station.

Step 17: The target base station sends a HO_Complete message to the serving base station, informing the serving base station that the MS has successfully entered the network at the target base station.

Step 18: When the target base station judges that the data return is completed, it sends a deregistration message of data channel 1 to the anchor ASN-GW.

Step 19: After receiving the deregistration message of data channel 1, the anchor ASN-GW sends the corresponding deregistration message of data channel 2 to the serving base station.

Step20: (Optional) The serving base station sends a HO_Cnf message to the unselected target base stations, which carries a cancel handover cancellation instruction.

Step21: (Optional) The unselected target base station sends a HO_ACK handover confirmation message to the serving base station.

After receiving the HO_Complete message in the existing handover procedure, the S-BS releases the MS context. If the original data path (Data Path, DP) between S-BS and A-ASN still exists at this time, then release the DP.

During the handover process, the timing of deleting the MS user context by the S-BS does not take into account the scenario that the data integrity is guaranteed by the backhaul method. When the S-BS receives the HO_Complete message, the data return may not be completed, and the return data channel 2 has not been released. At this time, the MS user context cannot be deleted. The MS user context contains the DP information of the MS. Delete the MS user context before the DP is released. If you delete the MS user and delete all the DPs corresponding to the MS at the same time, of course including the DP used for the return, the return may not be completed. If all DPs corresponding to the MS are not deleted when the MS user context is deleted, the unreleased DPs of the MS will not be released normally, which will cause abnormal DP release and waste of DP resources.

Contents of the invention

The technical problem to be solved by the embodiments of the present invention is to provide a method for deleting the terminal context and a system for switching the terminal. By correctly selecting the timing of deleting the terminal context, it is ensured that the data return is completed and the return data channel is released normally.

To this end, an embodiment of the present invention provides a method for deleting a terminal context. After the terminal is switched from the source base station to the target base station, the method includes:

The target base station sends a return data channel deregistration message to the anchor access service network gateway;

After receiving the deregistration message, the anchor access service network gateway sends a return data channel deregistration message to the source base station;

The source base station deletes the context of the terminal after receiving the return data channel deregistration message and the HO_Complete message of all target base stations;

The target base station includes selected and unselected target base stations, wherein, after the selected target base station confirms that the terminal's service flow data return is completed, it sends a return data channel deregistration to the anchor access service network gateway information.

The embodiment of the present invention also provides a system for terminal handover, including a source base station, a target base station, and an anchor access service network gateway, wherein, after the terminal is handed over from the source base station to the target base station,

The target base station is configured to send a return data channel deregistration message to the anchor access service network gateway;

An anchor access service network gateway, configured to send back a data channel deregistration message to the source base station after receiving the deregistration message;

The source base station is configured to delete the context of the terminal after receiving the return data channel deregistration messages and HO_Complete messages of all target base stations;

The target base station includes selected and unselected target base stations, wherein, after the selected target base station confirms that the terminal's service flow data return is completed, it sends a return data channel deregistration to the anchor access service network gateway information.

Using the solution of deleting the terminal context, the source base station deletes the context of the terminal after receiving the return data channel deregistration message and the HO_Complete message of all the target base stations, so that it will be cached in the S-BS during the handover process. The data is sent to the T-BS through the return channel, which ensures the integrity of the data sent to the terminal and also ensures the normal release of the return data channel.

Description of drawings

FIG. 1 is a schematic diagram of data return in the prior art;

Fig. 2 is a flow chart of switching to ensure data integrity in the prior art using a data return method;

FIG. 3 is a flow chart of unregistering a return data channel according to an embodiment of the present invention;

FIG. 4 is a flow chart of unregistering a return data channel according to an embodiment of the present invention;

FIG. 5 is a flow chart of unregistering a return data channel according to an embodiment of the present invention;

FIG. 6 is a flow chart of unregistering a return data channel according to an embodiment of the present invention;

FIG. 7 is a flow chart of unregistering a return data channel according to an embodiment of the present invention;

FIG. 8 is a schematic diagram of a system in which a terminal performs handover according to an embodiment of the present invention;

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings.

A specific embodiment of the present invention provides a method for deleting a terminal context, where the terminal is handed over from a source base station to a target base station, including the following steps:

The target base station sends a return data channel deregistration message to the anchor access service network gateway;

After receiving the deregistration message, the anchor access service network gateway sends a return data channel deregistration message to the source base station;

The source base station deletes the context of the terminal after receiving the return data channel deregistration message and the HO_Complete message of all target base stations;

The target base station includes selected and unselected target base stations, wherein, after the selected target base station confirms that the terminal's service flow data return is completed, it sends a return data channel deregistration to the anchor access service network gateway information.

After the terminal switches from the source base station to the target base station and establishes an air interface connection with the target base station, the selected target base station sends the HO_Complete message to the anchor access service network gateway, and the anchor access The serving network gateway forwards the HO_Complete message to the source base station.

A relay access service network gateway may also be included between the anchor access service network gateway and the target base station or the source base station, and the relay access service network gateway forwards the deregistration message and the HO_Complete message.

A method for deleting a terminal context in the present invention will be described in detail below through two specific embodiments.

Embodiment 1, as shown in Figures 3, 4, and 5.

100. After the terminal is handed over from the source base station to the target base station, the target base stations respectively send a return data channel deregistration message to the anchor access service network gateway, which is used to register all The backhaul data channel is deregistered; or, the target base station sends multiple backhaul data channel deregistration messages to the anchor access service network gateway, respectively, for deregistering the backhaul data channel corresponding to each service flow. (Wherein, the target base station includes selected and unselected target base stations, the same below.)

In the steps before the terminal is handed over from the source base station to the target base station, each service flow that needs to be guaranteed for data integrity of the terminal has been transferred between the source base station S-BS, each target base station T-BS, and the anchor access service network The return data channel Data Path1 and Data Path2 and the general data channel Data Path3 are pre-registered between the gateway Anchor ASN GW.

After receiving the HO_Cnf (Cancel) message, each unselected T-BS sends a return data channel deregistration message to the Anchor ASN-GW to deregister Data Path1 and/or Data Path3, and the deregistration message can be It is a deregistration message, which is used to deregister Data Path1 and/or Data Path3 of all pre-established service flows corresponding to the terminal. It is also possible to send multiple deregistration messages to deregister Data Path1 and/or Data Path3 of each service flow respectively. After the Data Path1 and/or Data Path3 of all service flows corresponding to the terminal are deregistered, the unselected T-BS deletes the terminal context of the terminal.

The selected T-BS, after confirming that all the service flows of the terminal are returned, sends a return data channel deregistration message to deregister all Data Path1 corresponding to the terminal, as shown in Figure 5. It may also be that, after the selected T-BS confirms that a certain service flow of the terminal is returned, it sends a plurality of Data Path deregistration messages respectively to deregister each Data Path1 corresponding to the service flow, such as Figure 3 and Figure 4 show.

105. After receiving one or more backhaul data channel deregistration messages from each target base station, the anchor access service network gateway sends a backhaul data channel deregistration message to the source base station respectively, which is used for unregistering the backhaul data channel with the source base station. or, after receiving multiple deregistration messages from each target base station, the anchor access service network gateway sends multiple backhaul data channel deregistration messages to the source base station respectively, for Deregister the return data channel corresponding to each service flow.

After the Anchor ASN-GW receives the Data Path1/3 deregistration message sent by the unselected T-BS, it sends back the data channel deregistration message to the S-BS, and deregisters the corresponding Data Path2. Similarly, the return data path deregistration message may be to deregister all the Data Path2s that are pre-established between the S-BS and the unselected T-BS corresponding to the terminal. It is also possible to send multiple return data channel deregistration messages to deregister each Data Path2 respectively.

After the Anchor ASN-GW receives the Data Path1 deregistration message sent by the selected T-BS, it sends back the data channel deregistration message to the S-BS, and deregisters the corresponding Data Path2, as shown in Figure 4 and Figure 4. 5. It may also be that after the Anchor ASN-GW waits to receive the Data Path1 deregistration message corresponding to all service flows of the terminal, it sends a return data channel deregistration message to the S-BS, and deregisters all corresponding Data Path2s, As shown in Figure 3.

110. The source base station deletes the context of the terminal after receiving all the backhaul data channel deregistration messages and HO_Complete messages.

The S-BS confirms that all T-BS return data channels Data Path2 are unregistered, and after receiving the HO_Complete message, deletes the terminal context of the terminal.

A relay access service network gateway may also be included between the anchor access service network gateway and the target base station or the source base station, and the relay access service network gateway responds to the deregistration message and the HO_Complete The message is forwarded.

Embodiment 2, as shown in Figures 6 and 7.

200. After the terminal is handed over from the source base station to the target base station, the target base stations respectively send a return data channel deregistration message to the anchor access service network gateway, which is used to register all The backhaul data channel is deregistered; or, the target base station sends multiple backhaul data channel deregistration messages to the anchor access service network gateway, respectively, for deregistering the backhaul data channel corresponding to each service flow.

In the steps before the handover process from the source base station to the target base station, the terminal has performed Data Path1 and /or Data Path3 and/or Data Path2 pre-registration.

After receiving the HO_Cnf (Cancel) message, the unselected T-BS sends a data channel deregistration message to the Anchor ASN-GW to deregister Data Path1 and/or Data Path3, and the deregistration message may be the All pre-established Data Path1 and/or Data Path3 corresponding to the terminal are deregistered. It is also possible to send multiple deregistration messages to deregister Data Path1 and/or Data Path3 of each service flow respectively. After all Data Path1 and/or Data Path3 corresponding to the terminal are deregistered, the T-BS deletes the terminal context of the terminal.

After the selected T-BS confirms that all the service flows of the terminal are returned, it sends a return data channel deregistration message to deregister all Data Path1 corresponding to the terminal, as shown in Figure 7. It may also be that, after the selected T-BS confirms that a certain service flow of the terminal is returned, it sends Data Path deregistration messages respectively to deregister the Data Path1 corresponding to the service flow, as shown in Figure 6 Show.

205. After receiving the deregistration message, the anchor access service network gateway sends only one return data channel deregistration message to the source base station, and the return data channel deregistration message is used for the anchor access service network gateway All return data channels between the source base station and the source base station are deregistered.

After the Anchor ASN-GW receives all the Data Path1/3 deregistration messages sent by the unselected T-BS and the Data Path1 deregistration message sent by the selected T-BS, it sends a return data channel deregistration message to The S-BS deregisters all Data Path2s corresponding to the terminal, as shown in Figures 6 and 7. The return data channel deregistration message may also deregister all Data Path0 and Data Path2 corresponding to the terminal.

210. After receiving the return data channel deregistration message and the HO_Complete message, the source base station deletes the context of the terminal.

The S-BS confirms that the Data Path2 of all T-BSs are unregistered, and after receiving the HO_Complete message, deletes the terminal context of the terminal.

The method further includes the first relay access service network gateway forwarding the deregistration message and the HO_Complete message between the target base station and the anchor access service network gateway, and/or

The second relay access service network gateway forwards the deregistration message and the HO_Complete message between the anchor access service network gateway and the source base station.

At the same time, the embodiment of the present invention also provides a system for terminal handover, including a source base station, a target base station, and an anchor access service network gateway, wherein, when the terminal is handed over from the source base station to the target base station,

The target base station is configured to send a return data channel deregistration message to the anchor access service network gateway;

An anchor access service network gateway, configured to send back a data channel deregistration message to the source base station after receiving the deregistration message;

The source base station is configured to delete the context of the terminal after receiving the return data channel deregistration messages and HO_Complete messages of all target base stations;

The target base station includes selected and unselected target base stations, wherein, after the selected target base station confirms that the terminal's service flow data return is completed, it sends a return data channel deregistration to the anchor access service network gateway information.

The system further includes: a first relay access service network gateway, configured to forward the deregistration message and the HO_Complete message between the target base station and the anchor access service network gateway, and/or

The second relay access service network gateway is configured to forward the deregistration message and the HO_Complete message between the anchor access service network gateway and the source base station.

After the terminal switches from the source base station to the target base station and establishes an air interface connection with the target base station, the selected target base station sends the HO_Complete message to the anchor access service network gateway, and the anchor access The serving network gateway forwards the HO_Complete message to the source base station.

Through the description of the above embodiments, those skilled in the art can clearly understand that the present invention can be realized by means of software plus a necessary general-purpose hardware platform, and of course it can also be realized by hardware. The above embodiments are only used to illustrate the present invention. The technical scheme of the invention is not limited thereto; although the present invention has been described in detail with reference to the aforementioned embodiments, those of ordinary skill in the art should understand that: it can still modify the technical solutions described in the aforementioned embodiments, or Some of the technical features are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims (8)

1. A method for deleting a terminal context, after the terminal is switched from a source base station to a target base station, it is characterized in that it includes: The target base station sends a return data channel deregistration message to the anchor access service network gateway; After receiving the deregistration message, the anchor access service network gateway sends a return data channel deregistration message to the source base station; The source base station deletes the context of the terminal after receiving the handover completion HO_Complete message and the return data channel deregistration messages of all target base stations; The target base station includes selected and unselected target base stations, wherein, after the selected target base station confirms that the terminal's service flow data return is completed, it sends a return data channel deregistration to the anchor access service network gateway information. 2. The method of claim 1, wherein, The target base station sending the return data channel deregistration message to the anchor access service network gateway includes: The target base stations respectively send a backhaul data channel deregistration message to the anchor access service network gateway, which is used to deregister all backhaul data channels between them and the anchor access service network gateway; or, the target base stations respectively Send multiple backhaul data channel deregistration messages to the anchor access service network gateway for deregistering the backhaul data channels corresponding to each service flow; The sending of the return data channel deregistration message by the anchor access service network gateway to the source base station includes: After receiving one or more deregistration messages from each target base station, the anchor access service network gateway sends a backhaul data channel unregistration message to the source base station, which is used to unregister the backhaul data channel between the source base station and the source base station. Perform de-registration; or, after receiving multiple de-registration messages from each target base station, the anchor access service network gateway sends multiple return data channel de-registration messages to the source base station, respectively, for corresponding to each service flow The return data channel for unregistering. 3. The method of claim 1, wherein, The target base station sending the return data channel deregistration message to the anchor access service network gateway includes: The target base stations respectively send a backhaul data channel deregistration message to the anchor access service network gateway, which is used to deregister all backhaul data channels between them and the anchor access service network gateway; or, the target base stations respectively Send multiple backhaul data channel deregistration messages to the anchor access service network gateway for deregistering the backhaul data channels corresponding to each service flow; The sending of the return data channel deregistration message by the anchor access service network gateway to the source base station includes: After the anchor access service network gateway receives the deregistration message, it sends only one return data channel deregistration message to the source base station, and the return data channel deregistration message is used for the anchor access service network gateway and the source base station All backhaul data channels between base stations are deregistered. 4. The method according to any one of claims 1-3, characterized in that, after the terminal is handed over from the source base station to the target base station and an air interface connection is established with the target base station, the selected target base station reports to the anchor The access service network gateway sends the HO_Complete message, and the anchor access service network gateway forwards the HO_Complete message to the source base station. 5. The method according to claim 1, wherein the method further comprises: The first relay access service network gateway forwards the deregistration message and the HO_Complete message between the target base station and the anchor access service network gateway, and/or The second relay access service network gateway forwards the deregistration message and the HO_Complete message between the anchor access service network gateway and the source base station. 6. A system for terminal handover, characterized in that it includes a source base station, a target base station, and an anchor access service network gateway, wherein, after the terminal is handed over from the source base station to the target base station, The target base station is configured to send a return data channel deregistration message to the anchor access service network gateway; An anchor access service network gateway, configured to send back a data channel deregistration message to the source base station after receiving the deregistration message; The source base station is configured to delete the context of the terminal after receiving the handover completion HO_Complete message and the return data channel deregistration messages of all target base stations; The target base station includes selected and unselected target base stations, wherein, after the selected target base station confirms that the terminal's service flow data return is completed, it sends a return data channel deregistration to the anchor access service network gateway information. 7. The system according to claim 6, further comprising: The first relay access service network gateway is configured to forward the deregistration message and the HO_Complete message between the target base station and the anchor access service network gateway, and/or The second relay access service network gateway is configured to forward the deregistration message and the HO_Complete message between the anchor access service network gateway and the source base station. 8. The system according to claim 6, wherein after the terminal is handed over from the source base station to the target base station and establishes an air interface connection with the target base station, the selected target base station provides an anchor access service network The gateway sends the HO_Complete message, and the anchor access service network gateway forwards the HO_Complete message to the source base station.

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