WO2008040218A1

WO2008040218A1 - A handover method and a system based on media independent handover technology

Info

Publication number: WO2008040218A1
Application number: PCT/CN2007/070677
Authority: WO
Inventors: Junxiang Guo
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2006-09-12
Filing date: 2007-09-12
Publication date: 2008-04-10
Also published as: CN101146331A; CN101146331B

Abstract

The present invention discloses a handover method and a system based on the media independent handover technology, in which the key is that an operation of avoiding data losing is perform not after handover complete but after receiving handover commit response during handover, so improving the efficient of data forwarding and the efficient of handover, and reducing the time delay of handover. Further more, perfecting the existing media independent handover, the steps can be set optional step not necessary step because the existing part of media accessing technologies do not support the handover complete message transferring between mobile node and candidate network node. But the handover complete message transferring between mobile node and candidate network node is necessary. The present invention enables the existing media accessing technology to completely support media independent handover flow in the case technology altering as small as.

Description

Switching method and system based on media independent switching technology

This application claims priority to Chinese Patent Application No. 200610127555.8, entitled "Switching Method and System Based on Media Independent Switching Technology", filed on September 12, 2006, the entire contents of which are incorporated by reference. In this application.

Technical field

The present invention relates to the field of communication technologies, and in particular, to a handover method and system based on a media independent handover technique.

Background technique

Currently, in order to solve the problem of roaming handover between mobile users in IEEE 802.3/802.11/802.16/3GPP/3GPP2 systems, an IEEE 802.21 working group has been established, which is responsible for formulating a common handover framework for wired and wireless IEEE 802 standards (such as IEEE). 802.3/11/16) and 3G standards, the requirements for switching between different standards and the corresponding switching mechanism.

The purpose of 802.21 (media-independent handover) standard development is to provide a handover process between different types of media, to enhance the user's experience on mobile devices by supporting switching between different types of media, with the goal of eventually enabling mobile devices to roam between networks. It automatically selects the best type of network connection and seamlessly switches the voice path without user intervention.

The media-independent switching solution of 802.21 introduces an architecture that ensures continuity of service switching between different types of media. To achieve seamlessness and continuity of such switching, a set of switching function sets needs to be implemented between network elements. . Configuring these switching function sets in the mobility management protocol stack of the network element forms a new protocol layer called the Media Independent Handover (MIH) protocol layer. The MIH layer protocol stack provides the following services:

1. MIH Event Service (MIH-ES): Provides event classification, event filtering, and event reporting of dynamically changing events on link characteristics, link status, and link quality.

2. MIH Command Service (MIH-CS): Provides MIH user management services, control and link behavior related to handover and mobility.

3. MIH Information Service (MIH-IS): Provides characteristics of the service network and surrounding networks, as well as details of the service. This information is used for effective system access and handover decisions.

The media-independent handover is generally divided into two situations: the terminal, that is, the mobile node (MN, Mobile Node) initiation and the network initiation, which are respectively described below. FIG. 1 is a flow chart of media independent handover initiated by a mobile node according to an existing embodiment. In steps 101 to 104, after the network discovery phase, the MN initiates an MIH acquisition information request (MIH_Get_Information Request) to the information server, and obtains an information response (MIH_Get_Information Response) from the information server. Get the information of the neighbor network around the MN and select the target network.

Steps 105-108, the mobile node sends an MIH initiate handover request (MIH_Handover_Initiate_Request) message to the serving network node (Serving PoS); after receiving the message, the serving network node sends an MIH handover request (MIH_Handover-Prepare Request) message to the Or multiple target network nodes (Candidate PoS) to query the resource status of the target network node, each target network node responds to the result of the resource query through the MIH_Handover_Prepare Response message; the response of the target network node is checked. Afterwards, the serving network node informs the mobile node about the availability of resources at the target network node through the MIH-Handover-Initiate-Request message.

Steps 109-112, the mobile node determines the target network node to be handed over according to the result of the MIH_Handover_Initiate Response message, and sends an MIH Handover Commit Request message to the serving network node to submit a media-independent handover; The serving network node may notify the target network node that the mobile node is to be handed over to the target network through the MIH Handover Commit Request message; the serving network node receives the MIH handover request response (MIH_Handover_Commit Response) message from the target network node, and then passes the MIH. The MIH_Handover-Commit Response message informs the mobile node of the result of the handover execution. Among them, steps 110 ~ 111 are optional steps.

Step 113: The high level performs the switching operation, that is, enters the handover execution phase.

Steps 114-115, after the high-level handover is completed, the mobile node sends a MIH_Handover-Complete Request message to the target network node; and receives a MIH Handover Complete Response message from the target network node.

At this point, the handover process initiated by the mobile node ends.

FIG. 2 is a flow chart of network-initiated media independent handover according to an existing embodiment.

Steps 201-202, the service network node saves or interacts through the message, such as MIH—Get—Information Request/Response, information obtained from the information server to the neighbor network around the mobile node.

Steps 203~204: After the handover condition is triggered, the serving network node sends a MIH_Handover-Prepare Request message to one or more target network nodes (Candidate PoS) to query the resource status of the target network node. The target network node responds to the result of the resource query through the MIH_Handover-Prepare Response message.

Steps 205~206, the serving network node sends an MIH_Handover_Initiate Request message to the mobile node to initiate the handover process. The mobile node sends an MIH_Handover-Initiate Response message to the serving network node in response to its request.

Steps 207~208, the serving network node sends an MIH_Handover_Commit Request message to the target network node, to indicate that the mobile node will switch to the target network, and receives the MIH_Handover-Commit Response message from the target network node. These two steps are optional and may be performed after step 209 210.

Steps 209-210, the serving network node sends an MIH_Handover_Commit Request message to the mobile node, submits a handover request, and receives an MIH_Handover-Commit Response message from the mobile node, in response to the result of submitting the handover request.

Step 211: The high level performs the switching operation, that is, enters the handover execution phase.

Step 212 213, after the high-level handover is completed, the mobile node sends an MIH_Handover-complete Request message to the target network node; and receives the MIH_Handover-Complete Response message from the target network node.

At this point, the network initiated handover process ends.

The above implementation has at least the following problems:

1. There is an inconsistency with the description of the current draft standard numbered P802-21-D01-09.

The current draft standard describes that after the handover is completed, the target network node should notify the original service network node that the handover has been completed, indicating that the original service network node can release the original connection resources in time. However, in the above implementation, the handover complete request message is sent from the mobile node to the target network node. Since in the existing and evolved 3G technologies, the handover complete request message is sent from the target network node to the original serving network node, it does not support the handover complete request message from the mobile node to the target network node, therefore, the pair of 3G Changes to air interface messages are not of practical value. 2. There is no step in the above implementation to avoid data loss, and thus there is data loss in the handover process.

FIG. 3 is a flow chart of media independent handover initiated by a mobile node according to another prior embodiment. The main implementation process is substantially the same as that shown in Figure 1. The difference is that after the handover operation is completed, the target network node sends an MIH_Handover-complete Request message to the service network node; after that, the operation of avoiding data loss is started. For example, data forwarding or bi-cast operation is performed; finally, the serving network node sends an MIH_Handover-Complete Response message to the target network node. That is, steps 311 to 313 in the figure. Moreover, in the embodiment shown in FIG. 3, there is no step in which the mobile node sends an MIH_Handover_complete Request message to the target network node, that is, steps 114 and 115 in FIG. 1 do not exist.

FIG. 4 is a flow chart of network-initiated media independent handover according to another prior embodiment. The main implementation process is substantially the same as that shown in Figure 2. The difference is: After the handover operation is completed, the target network node sends an MIH_Handover-complete Request message to the serving network node; after that, the operation of avoiding data loss is started. For example, data forwarding or bi-cast operation is performed. Finally, the serving network node sends an MIH_Handover-Complete Response message to the target network node. That is, steps 411 to 413 in the figure. Moreover, in the embodiment shown in FIG. 4, there is no step in which the mobile node sends an MIH_Handover_complete Request message to the target network node, that is, steps 212 and 213 in FIG. 2 do not exist.

The other implementation described above has at least the following problems:

The step of avoiding data loss, such as data forwarding, is started after the handover completion request message is sent to the original serving network node. If the efficiency of data forwarding is low, the switching efficiency is low, and when the amount of data to be forwarded is large, the handover may be extended. .

Summary of the invention

The present invention provides a handover method and system based on a media independent handover technique to solve the problem of improving handover efficiency while avoiding data loss.

The technical solution of the present invention includes:

A handover method based on media independent handover technology, including:

The serving network node starts performing an operation of avoiding data loss with the target network node before the handover is performed; The switching process is performed between the user node and the target network node.

A handover system based on media independent handover technology, including a user node, a service network node, and a target network node,

The serving network node includes: means for performing an operation of avoiding data loss with the target network node before starting the handover, and controlling the switching operation between the user node and the target network node.

A communication network, including a monthly service network node and a target network node,

The operation for avoiding data loss of the present invention starts from execution after the handover is completed and starts to be executed before the handover is performed, thereby improving the efficiency of data forwarding while avoiding data loss, improving the switching efficiency, and reducing the handover delay.

DRAWINGS

1 is a flow chart of media independent handover initiated by a mobile node according to an existing embodiment; FIG. 2 is a flowchart of network-initiated media independent handover according to an existing embodiment;

3 is a flow chart of a media independent handover initiated by a mobile node according to another embodiment of the present invention; FIG. 4 is a flowchart of a network-initiated media independent handover according to another embodiment of the prior art; FIG. 5 is a flowchart according to an embodiment of the present invention. A media independent handover flow chart initiated by a mobile node; FIG. 6 is a flow chart of network initiated media independent handover according to an embodiment of the present invention.

detailed description

The invention includes: in the switching process, the operation of avoiding data loss is started after the completion of the handover, and then starts to be executed after receiving the handover submission response, thereby improving the efficiency of data forwarding, thereby improving the switching efficiency and reducing the handover. Delay. Furthermore, the existing media-independent handover procedure is improved. Since the existing partial media access technology does not support the handover completion message being transmitted between the mobile node and the target network node, this step is set as a Choose not a mandatory step. The transfer of the handover completion message between the target network node and the original serving network node is a mandatory step.

The following is a detailed description of the present invention by taking a mobile node as a user node as an example with reference to the accompanying drawings and specific embodiments. FIG. 5 is a flow chart of media independent handover initiated by a mobile node according to an embodiment of the invention.

Step 501: The mobile node acquires information about the neighbor network around the mobile node from the information server by using a message interaction. And one or more target networks to be switched are selected according to the switching policy.

Step 502: The mobile node sends an MIH_Handover_Initiate Request message to the current serving network node.

Step 503: After receiving the message, the serving network node sends an MIH_Handover-Prepare Request message to one or more target network nodes to query the resource status of the target network node.

Step 504: Each target network node responds to the service network node by using a MIH_Handover-Prepare Response message to respond to the result of the resource query.

Step 505: After checking the response of the target network node, the serving network node sends

MIH—Handover—Initiate Response notifies the mobile node of the availability of resources at the target network node. The mobile node determines the target network node to actually switch according to the result of the MIH_Handover_Initiate Response message.

Step 506: The mobile node sends an MIH_Handover_Commit Request message to the serving network node to submit a media-independent handover.

Step 507: The serving network node can notify the target network node that the mobile node is to be switched to the target network by using the MIH_Handover-Commit Request message.

Step 508: The service network node receives the MIH_Handover-Commit Response message from the target network node.

Step 509: The serving network node notifies the mobile node to switch the result of the submission execution through the MIH_Handover-Commit Response message.

Step 510, starting to perform operations for avoiding data loss, such as performing data forwarding or bi-casting operations.

Step 511, starting handover execution between the mobile node and the target node, such as establishing a layer 2 link, layer 3 MIP (Mobile Internet Protocol) registration, and the like.

Step 512: After the high-level handover is completed, the mobile node sends an MIH_Handover-Complete Request message to the target network node. This step is an optional step.

Step 513: The target network node sends an MIH_Handover_Complete Request message to the original serving network node to notify that the handover is completed. Step 514: The serving network node sends an MIH_Handover_Complete Response message to the target network node in response to its request.

Step 515: The target network node sends an MIH_Handover_Complete Response message to the mobile node in response to its request. This step exists with the presence of step 512.

At this point, the handover process initiated by the mobile node ends.

6 is a flow chart of network initiated media independent handover according to an embodiment of the invention.

Step 601: The service network node saves or obtains information about the neighbor network around the mobile node through message interaction.

Step 602: After the handover condition is triggered, the serving network node sends an MIH_Handover-Prepare Request message to one or more target network nodes to query the resource status of the target network node.

Step 603: The target network node responds to the result of the resource query by using an MIH_Handover-Prepare Response message.

Step 604: The serving network node sends an MIH_Handover_Initiate Request message to the mobile node to initiate a handover process.

Step 605: The mobile node sends an MIH_Handover_Initiate Response message to the serving network node in response to its request.

Step 606: The serving network node sends an MIH_Handover_Commit Request message to the target network node to indicate that the mobile node will switch to the target network node.

Step 607: The serving network node receives an MIH_Handover-Commit Response message from the target network node.

The above steps 606 and 607 are optional steps, and they may also be performed after steps 608 and 609. Step 608: The serving network node sends an MIH_Handover_Commit Request message to the mobile node to submit a handover request.

Step 609: The serving network node receives an MIH_Handover-Commit Response message from the mobile node.

So far, the serving network node has received the MIH_Handover-Commit Response message of the target network node and the mobile node respectively.

Step 610, starting an operation to avoid data loss, such as performing data forwarding or bi-casting operations. This step can be started after receiving the MIH_Handover-Commit Response message from the target network node, or after receiving the MIH_Handover-Commit Response message from the mobile node, and can also receive the above two The MIH—Handover—Commit Response message is executed before starting.

Step 611, starting handover execution between the mobile node and the target node, such as establishing a layer 2 link, layer 3 MIP registration, and the like.

Step 612: After the high-level handover is completed, the mobile node sends an MIH_Handover-Complete Request message to the target network node. This step is an optional step.

Step 613: The target network node sends an MIH_Handover_complete Request message to the original service network node to notify that the handover is completed.

Step 614: The serving network node sends an MIH_Handover_Complete Response message to the target network node in response to the request.

Step 615: The target network node sends an MIH_Handover_Complete Response message to the mobile node in response to its request. This step exists with the presence of step 612.

At this point, the network initiated handover process ends.

It can be seen from the foregoing embodiments that the present invention also improves the existing media-independent handover procedure, regardless of the handover initiated by the mobile node or the network-initiated handover, due to the existing partial media access technology. The handover completion message is not supported to pass between the mobile node and the target network node, so this step is set as an optional, not mandatory, step. The transfer of the handover completion message between the target network node and the original serving network node is a mandatory step. In this way, existing media access technologies can fully support media-independent switching processes with minimal technical changes.

It should be noted that, regardless of the handover initiated by the mobile node or the handover initiated by the network, the operation of avoiding data loss may continue the entire handover process, and according to the actual amount of data, the operation of avoiding data loss is performed. It may continue until the service network node sends the MIH_Handover-Complete Response message.

In addition, for the flow shown in FIG. 5, in the actual application, the operation of avoiding data loss, that is, step 510, may be performed after step 509, or may be performed before step 509, or may be performed simultaneously with step 509. That is, there is no strict chronological order between steps 509 and 510. It will be understood that, although the above description uses a sequential description of the steps of the method for ease of understanding, it should be noted that the order of the above steps is not strictly limited. For example, operations that avoid data loss can improve switching efficiency as long as they are started before the switch execution phase. Therefore, operations that avoid data loss can be initiated before the switch commits the response.

The present invention also provides a handover system based on a media independent handover technology, including a mobile node, a service network node, and a target network node, where

The service network node further includes: means for performing an operation of avoiding data loss with the target network node after receiving the handover submission response, and controlling a handover operation between the mobile node and the target network node; wherein the data is avoided Lost operations include: data forwarding operations, or bi-cast operations;

When the handover is initiated by the mobile node, the service network node receives the handover submission response from the target network node; the service network node further includes: means for returning the handover submission response to the mobile node.

When the handover is initiated by the network, the serving network node receives the handover submission response including the handover submission response from the mobile node and the target network node.

The target network node further includes: means, after the handover operation is completed, sending a handover completion request message to the serving network node, and receiving a handover complete response message from the serving network node.

Further, the mobile node further includes: after the handover operation is completed, sending, by the target network node, a handover complete request message; the target network node further includes: after receiving the handover complete response message from the serving network node, sending, to the mobile node, A device that switches the completion response message.

It can be understood that the network entity described in the embodiment of the present invention can be implemented by using hardware or any suitable combination of software and hardware. The method described in this embodiment of the present invention can be implemented by using software, so the present invention can also be implemented by a data carrier or a carrier. The data storage device of the software is implemented. The network entity of the present invention is preferably applied to a mobile communication network, but it can be understood that it can be applied to any type of communication network, such as a wired network, a fixed network, a satellite network, or the like. Correspondingly, the user node of the present invention is not limited to a mobile node, and may be a non-mobile node.

The above description is only the preferred embodiment of the present invention and is not intended to limit the scope of the present invention. Any modifications, equivalents, improvements, etc. made within the spirit and scope of the invention are intended to be included within the scope of the invention.

Claims

Rights request

A handover method based on a media-independent handover technique, comprising: a service network node starts performing an operation of avoiding data loss with a target network node before performing handover execution;

The switching process is performed between the user node and the target network node.

2. The method according to claim 1, wherein the serving network node starts performing an operation of avoiding data loss with the target network node after receiving the handover submission response.

The method according to claim 1 or 2, wherein after the handover is completed, the method further comprises: the target network node sending a handover completion request to the serving network node.

4. The method according to claim 3, wherein the serving network node sends a handover completion response to the target network node after receiving the handover completion request.

The method according to claim 2, wherein when the handover is initiated by a user node, the handover submission response received by the serving network node is from a target network node;

Before or after or simultaneously with the operation of avoiding data loss between the service network node and the target network node, the method further includes: returning a handover submission response to the user node.

6. The method according to claim 2, wherein, when the handover is initiated by a network, the handover submission response received by the serving network node comprises a handover submission response from a user node and/or a target network node.

The method according to claim 3, wherein before the target network node sends the handover completion request to the serving network node, the method further includes: the user node sending the handover completion request to the target network node.

8. The method according to claim 4, wherein the target network node sends a handover completion response to the user node after receiving the handover completion response from the serving network node.

The method according to any one of claims 1 to 8, wherein the operation for avoiding data loss comprises: a data forwarding operation, or a bi-cast operation.

The method according to any one of claims 1 to 9, wherein the user node is a mobile node.

11. A handover system based on media independent handover technology, comprising a user node, a service network node, and a target network node, wherein The serving network node includes: means for performing an operation of avoiding data loss with the target network node before starting the handover, and controlling means for performing a handover operation between the user node and the target network node.

12. The system of claim 11 wherein:

The target network node includes: means for transmitting a handover completion request to the serving network node after the handover operation is completed.

13. The system of claim 12, wherein

The serving network node further includes: means for transmitting a handover completion response to the target network node after receiving the handover completion request.

The system according to claim 11, wherein when the handover is initiated by a user node, the handover submission response received by the serving network node is from a target network node;

The serving network node further includes: means for returning a handover submission response to the user node.

15. The system according to claim 11, wherein when the handover is initiated by a network, the handover submission response received by the serving network node comprises a handover submission response from a user node and/or a target network node.

16. A system according to any one of claims 11 to 13 wherein:

The user node further includes: means for transmitting a handover completion request to the target network node after the handover operation is completed.

The system according to any one of claims 11 to 16, wherein the target network node further comprises: means for transmitting a handover completion response to the user node after receiving the handover completion response from the serving network node.

The system according to any one of claims 11 to 17, wherein the operation for avoiding data loss comprises: a data forwarding operation, or a bi-cast operation.

The system according to any one of claims 11 to 18, wherein the serving network node starts performing an operation of avoiding data loss with the target network node after receiving the handover submission response.

The switching system according to any one of claims 11-19, wherein the user node is a mobile node.

21. A communication network comprising a service network node and a target network node, wherein The serving network node includes: means for performing an operation of avoiding data loss with the target network node before starting the handover, and controlling means for performing a handover operation between the user node and the target network node.

22. The network of claim 21, wherein:

The network according to claim 21 or 22, wherein the serving network node starts performing an operation of avoiding data loss with the serving network node after receiving the handover submission response.