WO2012167435A1

WO2012167435A1 - Method and apparatus for lossless handover

Info

Publication number: WO2012167435A1
Application number: PCT/CN2011/075556
Authority: WO
Inventors: 柯宏; 李玲
Original assignee: 华为技术有限公司
Priority date: 2011-06-10
Filing date: 2011-06-10
Publication date: 2012-12-13
Also published as: CN102265674A

Abstract

The embodiments of the present invention provide a method and an apparatus for lossless handover, and relate to the technical field of communications, in order to efficiently improve the lossless handover performance. The method for lossless handover includes: transmitting an indication message indicating the data processing rules adopted by a source Base Station (BS) to a target BS; and transmitting the service data of the terminal performing the handover to the target BS, wherein the service data is compressed based on the data processing rules. The present invention is applicable in a wireless communication system.

Description

Method and device for lossless switching

The present invention relates to the field of communications technologies, and in particular, to a method and apparatus for lossless handover. Background technique

The handover (HO, Handover) refers to the mobile terminal moving from one base station coverage cell to another, and the signal strength of the target cell will gradually increase due to distance or other reasons, in order to obtain Better signal quality and also the process of changing the mobile terminal to a better target cell to ensure business continuity. The HO is an important function in the wireless communication technology to support mobility management, which ensures that the terminal can provide better signal quality and ensure continuity of services when the wireless channel changes.

Switching Data Integrity (HO DI, Handover Data Integrity), also known as lossless handover, reduces the data loss of the mobile terminal during the handover process through a series of processes, ensures better continuity of the mobile terminal service data, and avoids application layer reporting. The delay caused by packet loss and retransmission improves the performance of each communication service. The HO DI is essentially in the handover execution phase, the source base station stops transmitting air interface data to the mobile terminal and buffers it, and returns the buffered mobile terminal air interface data to the target base station to ensure that the data of the mobile terminal during the handover process is not lost.

In the prior art, in the HO DI process, the air interface data buffered by the source base station may be data that has been processed by the source base station and is waiting to be sent in the air interface. In order to ensure that the data can be sent back to the target base station after the data is transmitted back, the source base station re-decodes the data that is transmitted back to the target base station, and then sends the data back to the target base station. After receiving the data, the target base station performs the backhaul data. After being processed by compression, it is sent to the terminal. In this way, since the compression processing of the data by the base station is generally time consuming and resource intensive, if the backhaul data is large, the compression and decompression processing of the source base station and the recompression processing of the target base station waste a lot of time and resources, limiting The performance of HO DI. Summary of the invention

A main object of embodiments of the present invention is to provide a method and apparatus for lossless handover that can effectively improve the performance of lossless handover.

In order to achieve the above object, the following technical solutions are used in the embodiments of the present invention:

A method of lossless switching, comprising:

Sending an indication message of a data processing rule used by the source base station to the target base station;

Transmitting the service data of the handover terminal to the target base station, and the service data is compressed according to the data processing rule. A method of lossless switching, comprising:

Receiving, by the source base station, an indication message of a data processing rule used by the source base station; receiving service data of the handover terminal sent by the source base station, where the service data is compressed according to the data processing rule; Transmitting service data to the switching terminal ₍ a method for lossless handover, comprising:

Receiving data processing rules of service data transmitted by the target base station and service data compressed according to the data processing rule;

Decompressing the received service data according to the data processing rule. A base station comprising:

a sending unit, configured to send, to the target base station, an indication message of a data processing rule used by the base station;

a processing unit, configured to perform compression processing on the service data of the handover terminal according to the data processing rule; The sending unit is further configured to send, to the target base station, the service data that is compressed according to the data processing rule. A base station comprising:

a receiving unit, configured to receive an indication message of a data processing rule used by the source base station by the source base station, and receive service data of the handover terminal sent by the source base station, where the service data is in accordance with the data processing rule The compression process is performed; the service data subjected to the compression process is sent to the handover terminal. A mobile terminal includes:

a receiving unit, a data processing rule for receiving service data sent by the target base station, and service data compressed according to the data processing rule;

And a processing unit, configured to perform decompression processing on the received service data according to the data processing rule. After the foregoing technical solution, the method and apparatus for lossless handover provided by the embodiment of the present invention, when performing lossless handover, the source base station sends its used data processing rule to the target base station, so that the source base station controls the handover terminal. After the service data is compressed, it is not necessary to perform inverse processing such as decompression on the service data, and the data can be directly sent to the target base station, and the target base station does not need to perform compression processing on the received data again, and can directly receive the data. The data is sent to the handover terminal. Therefore, the computing resources of the source base station and the target base station are saved, and the performance of the lossless handover is effectively improved. DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the prior art description will be briefly described below, obviously, the following The drawings in the description are only some of the embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive labor.

FIG. 1 is a flowchart of a method for lossless handover according to an embodiment of the present invention;

FIG. 2 is a flowchart of a method for lossless handover according to an embodiment of the present invention;

FIG. 3 is a flowchart of a method for lossless handover according to an embodiment of the present invention;

4 is a specific flowchart of a method for lossless handover according to an embodiment of the present invention; FIG. 5 is a structural block diagram of a base station 1 according to an embodiment of the present invention;

FIG. 6 is a structural block diagram of a base station 2 according to an embodiment of the present invention;

FIG. 7 is another structural block diagram of a base station 2 according to an embodiment of the present invention;

FIG. 8 is a structural block diagram of a mobile terminal according to an embodiment of the present invention. detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

It should be noted that, in the embodiment of the present invention, the mobile terminal performing cell handover is referred to as a handover terminal, and the handover terminal switches from the cell covered by the source base station to the cell covered by the target base station.

As shown in FIG. 1 , a method for lossless handover provided by an embodiment of the present invention, based on a source base station, includes:

Step 11: Send an indication message of a data processing rule used by the source base station to the target base station. In the non-destructive handover process, the source base station stops transmitting air interface service data to the handover terminal and buffers it during the handover execution phase. After the source base station and the target base station establish a data return transmission channel, the source base station returns the buffered service data. After the handover is completed, the target base station sends the service data returned by the source base station to the handover terminal to ensure that the data of the handover terminal during the handover process is not lost.

Since the air interface service data buffered by the source base station is usually already based on the data used by the source base station The processing rule is processed by the target base station, so that the data processing rule used by the source base station is known by the target base station, so that the data processing rule used by the source base station is known by the target base station. When the source base station returns data to the target base station, it does not need to perform inverse processing such as decompression on the data that has been processed by compression, and the like, and can directly send the data to the target base station, and the target base station does not need to return the source base station again. The data is compressed and can be directly sent to the handover terminal, which effectively saves the computing resources of the source base station and the target base station, and effectively improves the performance of the lossless handover.

Optionally, the source base station may carry a data processing rule of the service data of the switching terminal in the handover request (HO_Req) message sent to the target base station to the target base station, where the data of the service data of the terminal is switched by using the handover request The processing rule is notified to the target base station. Of course, the source base station may also send the data processing rule to the target base station by using other methods, for example, directly sending the indication message of the data processing rule to the target base station.

Specifically, the data processing rule may be a Payload Header Suppression (PRS) rule or a ROHC (Robust Header Compression) rule. The indication message of the PHS rule may include: PHSI (PHS Index, PHS index), PHSF (PHS Field, PHS domain), PHSM (PHS Mask, PHS mask), PHS S (PHS Size, PHS size), HSV (PHS Valid, PHS valid bit), PHS Rule Action (PHS rule action) and other parameters.

Step 12: Send service data of the handover terminal to the target base station, where the service data is compressed according to the data processing rule.

It should be noted that, in this step, the data that the source base station sends to the target base station to the target base station is the air interface service data of the switching terminal buffered by the source base station in the handover execution phase, and the data has been used by the source base station according to the The data processing rules are compressed. The source base station sends the service data of the handover terminal to the target base station to the target base station, and sends the service data to the target base station to the handover terminal by the target base station, so as to ensure that the data of the handover terminal during the handover process is not lost.

The method for lossless handover provided by the embodiment of the present invention, when performing lossless handover, the source base station sends the data processing rule used by the source base station to the target base station, so that the number of services of the source terminal station to the handover terminal According to the compression processing, it is not necessary to perform inverse processing such as decompression on the service data, and the data can be directly sent to the target base station, and the target base station does not need to perform compression processing on the received data again, and can directly receive the received data. The data is sent to the handover terminal. Therefore, the computing resources of the source base station and the target base station are saved, and the performance of the lossless handover is effectively improved. Corresponding to the method shown in FIG. 1 , as shown in FIG. 2 , the embodiment of the present invention further provides a method for lossless handover, based on a target base station, including:

Step 21: Receive an indication message of a data processing rule used by the source base station sent by the source base station.

The target base station receives the indication message of the data processing rule used by the source base station to learn the data processing rule used by the source base station to transmit the service data of the handover terminal to the target base station.

Specifically, in this step, the target base station receives the handover request message sent by the source base station, where the switch request message carries the data processing rule used by the active base station.

Optionally, the data processing rule includes: a load header compression PHS rule or a robust header compression ROHC rule. The indication message of the PHS rule may include: PHSI, PHSF, PHSM, PHSS, HSV, PHS Rule Action and the like.

Step 22: Receive service data of the handover terminal sent by the source base station, where the service data is compressed according to the data processing rule.

The target base station receives the service data of the handover terminal that is buffered by the source base station during the handover execution process, and the service data is compressed by the source base station according to the data processing rule. The reduced processed service data is sent to the switching terminal.

In this way, the switching terminal can learn the data processing rule, and decompress the service data compressed according to the data processing rule.

In the embodiment of the present invention, the target base station does not need to perform re-compression processing on the received service data, and directly sends the service data to the handover terminal, so that the handover terminal is guaranteed to be switched. The data in the process is not lost, and the computing resources of the target base station are saved, which effectively improves the performance of lossless handover.

Further, after the step 23, in the embodiment of the present invention, the communication between the target base station and the handover terminal may be performed according to the data processing rule used by the source base station, that is, after step 23, the target base station will follow the And the data processing rule is: performing compression processing on the downlink data to be sent to the handover terminal, and performing decompression processing on the uplink data sent by the handover terminal. Corresponding to the method shown in FIG. 1 and FIG. 2, as shown in FIG. 3, the embodiment of the present invention further provides a method for lossless handover, based on the handover terminal, including:

Step 31: Receive data processing rules of service data sent by the target base station and service data compressed according to the data processing rule.

The target base station sends the service data of the handover terminal that is buffered by the source base station during the handover execution to the handover terminal, and ensures that the data of the handover terminal during the handover process is not lost. Moreover, the target base station notifies the switching terminal of the data processing rule used by the data, and the switching terminal decompresses the service data compressed according to the data processing rule to ensure the reliability of the data communication. .

Step 32: Perform decompression processing on the received service data according to the data processing rule.

The method for lossless handover provided by the embodiment of the present invention, the handover terminal may directly receive the data processing rule according to the data processing rule, and perform decompression processing on the received service data. Therefore, when performing lossless handover, the source base station may The data processing rule used by the source station is sent to the target base station, and after the source base station compresses the service data of the handover terminal, the source base station does not need to perform the service data again. The inverse processing such as decompression can directly transmit the data to the target base station, and the target base station does not need to perform compression processing on the received data again, and can directly send the received data to the handover terminal, thereby saving the source base station and The computing resources of the target base station effectively improve the performance of lossless handover.

Further, after the step 32, in the embodiment of the present invention, the communication between the target base station and the handover terminal may be performed according to the data processing rule used by the source base station, that is, after the step 32, the handover terminal will follow the The data processing rule performs decompression processing on the downlink data sent by the target base station, and performs compression processing on the uplink data to be sent to the target base station. Further details are given.

The method for lossless handover in this embodiment is as shown in FIG. 4, where Path O is a data channel between an access service network gateway (ASN-GW) and a source base station SBS (Serving Base Station); Path 1 is the data return channel between the ASN-GW and the target base station TBS (Target Base Station). It exists during the handover process and is removed after the data backhaul is completed. Path 2 is the data return channel between the ASN-GW and the SBS. , exists during the handover process, and is removed after the data backhaul is completed; Path 3 is the data channel between the ASN-GW and the TBS. As shown in FIG. 4, this embodiment includes the following steps:

1 . The mobile terminal MS (Mobile Station) (ie, the handover terminal) that performs the cell handover sends a handover request MOB_MSHO-REQ message to the SBS, and triggers the preparation for handover;

2. The SBS sends a handover request HO_Req message to each candidate TBS through the ASN-GW. If the SBS supports data integrity DI, the HO-Req message indicates the DI capability of the SBS, and if the PHS of the SBS is enabled, the HO-Req message The PHS rule indicating the MS service flow (that is, the data processing rule of the SBS) includes: PHSI, PHSF, PHSM, PHSS, PHSV, PHS Rule Action and the like;

3. After receiving the HO_Req message, the TBS initiates the Path3 data path DP (Data Path) pre-establishment process to the ASN-GW, and sends the data channel pre-establishment to the ASN-GW. Request Path-Prereg-Req message and negotiate DI capability in the process; if TBS can support PHS, Path3 will directly use the PHS rule of SBS; ASN-GW negotiates the capability support information of DI according to SBS, TBS and itself Only three of them support DI, and at least one kind of DI mode that is supported together, the system is judged to support DI;

4. The TBS pre-establishes the response Path-Prereg-Rsp message through the data channel of the ASN-GW to obtain the handover response HO-Rsp message to the SBS through the ASN-GW, and carries the DI negotiation result; the SBS returns the handover response to the MS. Message MOB - BSHO-RSP message;

5, if the negotiation MS has the DI service flow enabled, the TBS initiates a pre-established return data path Pathl to the ASN-GW;

6. If the negotiation service flow is enabled with DI and the pre-registration of the return data channel Path1 is successful, the ASN-GW triggers the establishment of the backhaul tunnel Path2 between the ASN-GW and the SBS to the SBS; the backhaul tunnels Pathl and Path2 are pre-established. Upon successful, the SBS starts to return the air interface data of the cached MS to the TBS. After the data, the TBS can directly forward the backhaul data in the air interface, and does not need to perform PHS compression processing again. The data returned by the SBS first arrives at the ASN-GW through Path2, and is sent to the candidate TBS by the ASN-GW through Path2;

Steps 1 to 6 above are the preparation preparation phase;

7: The MS sends a handover indication MOB_HO-IND message to the SBS, indicating the selected TBS; the SBS sends a handover confirmation HO_Cnf message to the TBS;

It should be noted that the process and steps for the SBS to start transmitting data to the TBS in step 6 can be performed in parallel without affecting each other.

8, the TBS saves relevant information, and sends a handover confirmation HO_Ack message to the SBS;

9. The MS completes the re-entry network at the TBS;

The TBS will send the PHS rule and the corresponding service flow information obtained from the SBS to the MS, so that after the TBS re-enters the network, the MS can still perform the decompression processing on the downlink data according to the new PHS rule, and perform the uplink data on the uplink data. Compression processing 10, TBS, ASN-GW trigger Path3 registration process; ASN-GW stops sending data to SBS, and switches data channel to selected TBS;

Steps 7 to 10 above are the switching execution phase;

After completing the Path3 registration process between the ASN-GW and the TBS, the TBS sends a handover complete HO_Complete message to the SBS, confirming that the MS has entered the network in the TBS;

12. After receiving the HO_Complete message, the SBS returns a handover confirmation HO_Ack message to the TBS, and the SBS waits for the backhaul data transmission to complete, and then clears the context of the MS;

13 . The TBS judges that the data back is over, and initiates a request to the ASN-GW to delete the backhaul data channel Pathl;

14. After receiving the Path 1 deletion request sent by the TBS, the ASN-GW sends a request to the SBS to delete the backhaul data channel Path2; the SBS deletes the related resources of the backhaul data channel Path 2;

After the Path3 registration between the TBS and the ASN-GW is successful, the ASN-GW initiates the deletion of the PathO to the SBS.

The above steps 11 to 15 are the completion stages of the handover.

In the lossless handover method of the embodiment, the SBS sends the PHS rule used by the MS service flow to the TBS through the HO-Req message, so that the SBS does not need to perform inverse processing such as decompression on the service flow, and can directly send data to the TBS. TBS, and the TBS does not need to perform compression processing on the received data again, and can directly send the received data to the MS. Therefore, the computing resources of the SBS and the TBS are saved, and the performance of the lossless handover is effectively improved. Corresponding to the foregoing method, as shown in FIG. 5, an embodiment of the present invention further provides a base station 1 , which may be used as a source base station in a method embodiment, and includes:

The sending unit 101 is configured to send, to the target base station, an indication message of a data processing rule used by the base station 1;

The processing unit 102 is configured to perform compression processing on the service data of the handover terminal according to the data processing rule. The sending unit 101 is further configured to send, to the target base station, the service data that is processed by the processing unit 102 according to the data processing rule.

The base station 1 according to the embodiment of the present invention sends the data processing rule used by the base station 1 to the target base station when performing the lossless handover, and does not perform inverse processing such as decompression on the service data, and directly performs the data processing rule according to the data processing rule. The compressed data is sent to the target base station, so that the target base station does not need to perform processing such as compression on the received data again, and the received data can be directly sent to the handover terminal, thereby saving computing resources of the base station 1 and the target base station. , effectively improve the performance of lossless switching.

Specifically, the data processing rule may include a load header compression PHS rule or a robust header compression ROHC rule.

Optionally, the sending unit 101 is specifically configured to send a handover request message to the target base station, where the switch request message carries a data processing rule used by the base station 1. Corresponding to the foregoing method, as shown in FIG. 6, the embodiment of the present invention further provides a base station 2, which can be used as a target base station in the method embodiment, and includes:

The receiving unit 201 is configured to receive, by the source base station, an indication message of a data processing rule used by the source base station, and receive service data of the handover terminal sent by the source base station, where the service data is processed according to the data The rules are compressed;

The sending unit 202 is configured to send the data processing rule and the service data that is compressed according to the data processing rule to the switching terminal.

The base station 2 provided by the embodiment of the present invention does not need to perform re-compression processing on the service data sent by the received source base station, and directly sends the data processing rule and the data processing rule to the target base station to the handover terminal, so that The data of the handover terminal during the handover process is not lost, and the computing resources of the base station 2 are saved, thereby effectively improving the performance of the lossless handover.

Specifically, the data processing rule may include a load header compression PHS rule or a robust header compression ROHC rule. Optionally, the receiving unit 201 is specifically configured to receive a handover request message sent by the source base station, where the handover request message carries a data processing rule used by the active base station.

Further, as shown in FIG. 7, the base station 2 may further include a processing unit 203, configured to perform compression processing on downlink data to be sent to the handover terminal according to the data processing rule, and send uplink to the handover terminal. The data is decompressed. Corresponding to the foregoing method, as shown in FIG. 8, an embodiment of the present invention further provides a mobile terminal, which can be used as a handover terminal in the method embodiment, and includes:

The receiving unit 301 is configured to receive an indication message of a data processing rule of the service data sent by the target base station, and service data that is compressed according to the data processing rule;

The processing unit 302 is configured to perform decompression processing on the received service data according to the data processing rule.

The mobile terminal provided by the embodiment of the present invention can directly receive the data processing rule of the service data and the service data that is compressed according to the data processing rule, and solve the received service data according to the data processing rule. The compression process is performed. Therefore, when performing the lossless handover, the source base station may send the data processing rule used by the source base station to the target base station. After the source base station compresses the service data of the handover terminal, the source base station does not need to perform the service data again. The inverse processing such as decompression can directly transmit the data to the target base station, and the target base station does not need to perform compression processing on the received data again, and can directly send the received data to the handover terminal, thereby saving the source base station and The computing resources of the target base station effectively improve the performance of lossless handover.

Further, the processing unit 302 is further configured to perform decompression processing on the downlink data sent by the target base station according to the data processing rule, and perform compression processing on the uplink data to be sent to the target base station.

It should be noted that the embodiments of the present invention are particularly applicable to the global microwave interconnection access WiMAX. (Global Interoperability for Microwave Acces) The HO DI function in the network is also applicable to the HO DI function in the Long Term Evolution (LTE) network, and is also applicable to other wireless networks, which is not limited by the present invention. A person skilled in the art can understand that all or part of the process of implementing the above method embodiments may be completed by using computer program related hardware, and the foregoing program may be stored in a computer readable storage medium, when executed, The foregoing steps include the steps of the foregoing method embodiments; and the foregoing storage medium includes: a medium that can store program codes, such as a ROM, a RAM, a magnetic disk, or an optical disk.

The above is only the specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of changes or substitutions within the technical scope of the present invention. It should be covered by the scope of the present invention. Therefore, the scope of the invention should be determined by the scope of the appended claims.

Claims

Claim

A method for lossless switching, comprising:

Transmitting, by the target base station, service data of the handover terminal, where the service data is compressed according to the data processing rule.

The method according to claim 1, wherein the transmitting the indication message of the data processing rule used by the source base station to the target base station comprises:

And sending a handover request message to the target base station, where the handover request message carries a data processing rule used by the active base station.

The method according to claim 1 or 2, wherein the data processing rule comprises: a load head compression PHS rule or a robust header compression ROHC rule.

4. A method of lossless switching, characterized in that it comprises:

Receiving, by the source base station, an indication message of a data processing rule used by the source base station; receiving service data of the handover terminal sent by the source base station, where the service data is compressed according to the data processing rule;

And transmitting the data processing rule and the service data compressed according to the data processing rule to the switching terminal.

The method according to claim 4, wherein the indication message of the data processing rule used by the source base station sent by the source base station comprises:

Receiving a handover request message sent by the source base station, where the handover request message carries a data processing rule used by the active base station.

The method according to claim 4, wherein after the data processing rule and the service data that is compressed according to the data processing rule are sent to the switching terminal, the method further includes :

Compressing the downlink data to be sent to the handover terminal according to the data processing rule And performing decompression processing on the uplink data sent by the handover terminal.

The method according to any one of claims 4 to 6, wherein the data processing rule comprises: a load head compression PHS rule or a robust header compression ROHC rule.

8. A method of lossless switching, comprising:

Receiving data processing rules of the service data sent by the target base station and service data compressed according to the data processing rule;

Decompressing the received service data according to the data processing rule.

The method according to claim 8, wherein after the decompressing the received service data according to the data processing rule, the method further includes:

Decompressing the downlink data sent by the target base station according to the data processing rule, and performing compression processing on the uplink data sent to the target base station.

10. The method of claim 8 or 9, wherein the data processing rules comprise: load head compression PHS rules or robust header compression ROHC rules.

A base station, comprising:

a processing unit, configured to perform compression processing on the service data of the switching terminal according to the data processing rule;

The sending unit is further configured to send, to the target base station, the service data that is compressed according to the data processing rule.

The base station according to claim 11, wherein the sending unit is configured to send a handover request message to the target base station, where the handover request message carries a data processing rule used by the base station .

13. A base station, comprising:

a receiving unit, configured to receive an indication message of a data processing rule used by the source base station by the source base station, and receive service data of the handover terminal sent by the source base station, where the service data is in accordance with The data processing rule performs compression processing; the compressed processed service data is sent to the switching terminal.

14. The base station according to claim 13, wherein:

The receiving unit is specifically configured to receive a handover request message sent by the source base station, where the handover request message carries a data processing rule used by the active base station.

The base station according to claim 13, further comprising a processing unit, configured to perform compression processing on downlink data to be sent to the handover terminal according to the data processing rule, and send the downlink data to the handover terminal The uplink data is decompressed.

16. A mobile terminal, comprising:

And a processing unit, configured to perform decompression processing on the received service data according to the data processing rule.

The mobile terminal according to claim 16, wherein the processing unit is further configured to perform decompression processing on downlink data sent by the target base station according to the data processing rule, and treat the target to the target The uplink data sent by the base station is compressed.