WO2008089671A1

WO2008089671A1 - Method, system and terminal for reducing handover delay

Info

Publication number: WO2008089671A1
Application number: PCT/CN2008/070010
Authority: WO
Inventors: Liang Gu; Meng Liang
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2007-01-23
Filing date: 2008-01-03
Publication date: 2008-07-31
Also published as: CN101232698A; CN101232698B

Abstract

A method, system and terminal for reducing handover delay are provided, and the method comprises: the terminal receiving a message sent from a network side, the message including an indication which indicates a need of performing network-layer handovers, or including the indication which indicates the need of performing network-layer handovers and a new care of address generated for the terminal by the network side; the terminal performing the network-layer handovers by using the new care of address generated by itself or by using the new care of address generated by the network side.

Description

Method, system and terminal for shortening handover delay

This application claims priority to Chinese Patent Application No. 200710002706.1, entitled "Methods, Systems and Terminals for Shortening Switching Delay", filed on January 23, 2007, the entire contents of which are incorporated by reference. In this application.

Technical field

The present invention relates to a handover technique for a wireless metropolitan area network, and more particularly to a method, system and terminal for shortening handover delay.

Background technique

Worldwide Interoperability for Microwave Access (WiMAX) is a wireless metropolitan area network technology based on the IEEE 802.16 standard. Referring to Figure 1, the WiMAX network mainly includes a client (MSS/SS, Mobile Subscriber Station/Subscriber). Station), Access Service Network (ASN) and Connectivity Service Network (CSN), the Rl interface is an airborne wireless interface, which mainly provides physical layer and link layer connection functions. The terminal connects to the base station through the interface; the R3 interface is a transmission interface in the ASN and the CSN network, and provides a connection function of the terminal network layer, and the ASN network is interconnected through the R3 interface and the CSN network.

The client is a mobile user device, and the user uses the device to access the WiMAX network. The Mobile Internet Protocol version 6 (IPv6, IP version 6) enables the mobile user device to maintain movement between different access routers (ARs, Access Routers). The original IP connection is not interrupted.

When a mobile user equipment switches from one access router to another, it is unable to receive and send data packets for a period of time. This period is called handover delay. The handover delay includes a handover delay of the link layer and a handover delay of the network layer, where the handover delay of the network layer depends on the network layer mobility detection, the configuration of the new care-of address (NCoA, New Care-of Address), and The mobile IP (MIP, Mobile IP) binding update time is longer than the switching delay of the link layer, and the network layer has a long handover delay. This delay is unacceptable for real-time services.

The prior art 1 provides a network layer switching method caused by terminal mobility. Referring to FIG. 2, the method includes:

Step 201: After the terminal moves to complete the ASN handover process, the target access service network gateway (Target ASN-GW) initiates a network layer handover to the anchor access gateway (ASN-GW). Request message.

Step 202: The anchor ASN-GW sends a handover response message to the target ASN-GW, where the message carries the R3 context information of the terminal.

Step 203: The target ASN-GW sends a router advertisement (RA, Router Advertisement) message to inform the terminal of the new access router (AR, Access Router) information.

Step 204: The terminal acquires a new care-of address, and performs necessary address conflict detection (DAD, Duplicate Address Detection) on the address, where the new care-of address can be a network prefix in the terminal and the own interface identifier. The state mode is generated, or the new care-of address can be obtained through the Dynamic Host Configuration Protocol (DHCP).

Step 205 to step 206: The terminal sends a binding update message to the home agent (HA, Home Agent) or other communication node (CN, Corresponding Node) for binding update, and the home agent sends a binding confirmation message to the terminal to indicate that the binding update has been carry out.

Step 207: The target ASN-GW sends a handover confirmation message to the anchor ASN-GW, to notify the anchor ASN-GW terminal that the handover at the network layer has been completed.

Step 208: Optionally, if there is a data channel between the serving ASN-GW and the anchor ASN-GW, the anchor ASN-GW releases the data channel after receiving the handover confirmation message.

The prior art 2 provides a network layer switching method caused by resource optimization. Referring to FIG. 3, the method includes:

Step 301: The anchor ASN-GW initiates a network layer handover request message to the serving ASN-GW, where the message carries the R3 context information of the terminal.

Step 302: The serving ASN-GW sends a handover response message to the anchor ASN-GW.

Step 303: The service ASN-GW sends a router broadcast message to inform the terminal of the new access router information.

Step 304: The terminal acquires a new care-of address, and performs necessary address conflict detection on the address, where the new care-of address may be generated by the terminal in a stateless manner according to the network prefix and the interface identifier in the AR information, or may be passed. DHCP gets the new care-of address.

Step 305 to step 306: The terminal sends a binding update message to perform binding update with the home agent or other communication node, and the home agent sends a binding confirmation message to the terminal to indicate that the binding update is completed.

Step 307: The serving ASN-GW sends a handover confirmation message to the anchor ASN-GW to notify the anchor. The handover of the ASN-GW terminal at the network layer has been completed.

Step 308: After receiving the handover confirmation message, the anchor ASN-GW releases the data channel between the anchor ASN-GW and the serving ASN-GW.

The above two prior technologies are all MIP-based handover schemes. The prior art is to acquire the network prefix in the AR information after the terminal switches to the target ASN-GW, and then generate a new care-of address, and then The address performs address conflict detection. Finally, the terminal initiates a MIP binding message to complete the binding update process of the home agent and other communication nodes. Similarly, in the prior art, the new care-of address is configured after the terminal switches to the serving ASN-GW, and then the address conflict detection is performed on the address.

The above two existing technologies are configured to configure an NCoA address when the terminal performs network layer switching, and then perform address conflict detection on the address, which causes the network layer migration switching delay to be too long. In addition, when the terminal performs the mobile IP binding update, the peer processing entity of the binding message is the terminal and the home agent or other communication node, and the access router does not process, therefore, the access router cannot know that the mobile IP binding update is completed. After the instruction, the subsequent processing after the binding update cannot be completed, such as resource release. Finally, the above two prior art technologies consider that a network layer handover is required as long as the terminal receives the RA message sent by the new AR, provided that one terminal is only interconnected with one AR. When the terminal is interconnected with multiple ARs, if a new AR connection is sent and an RA message is sent, the terminal is still connected to the original AR, and the existing network layer mobility detection method causes the terminal to mistake the network. The layer needs to be switched to cause mis-switching, so that the IP service is affected. At the same time, the development of the wireless network will inevitably cause the base station to be shared by multiple ARs, and even the network-like interconnection structure between the base station and the AR is present, so the network layer moves. Sex detection methods are not conducive to the development of subsequent wireless networks.

Summary of the invention

The embodiments of the present invention provide a method, a system, and a terminal for shortening a handover delay, which can reduce a handover delay of a terminal at a network layer.

An embodiment of the present invention provides a method for shortening a handover delay, where the method includes:

Receiving, by the terminal, a message sent by the network side, where the message carries an indication that network layer handover needs to be performed, or carries an indication that network layer handover needs to be performed, and a new handover address generated by the network side for the terminal;

The terminal uses the new care-of address generated by itself or the new care-of address generated by the network side. Network layer switching.

The embodiment of the present invention further provides a system for shortening a handover delay. The system includes: a network side device, configured to generate a new care-of address for the terminal, and send an indication to the terminal that the network layer needs to be handed over, and a new care-of address or Information used to generate a new care-of address; and

The terminal is configured to acquire a new care-of address from the network side device, or obtain information for generating a new care-of address, and generate a new care-of address according to the information used to generate the new care-of address, and receive the need for the network-side device to send The network layer switching is performed by using the new care-of address when the indication of the network layer handover is performed.

In addition, an embodiment of the present invention further provides a terminal, where the terminal includes:

An obtaining unit, configured to acquire a new care-of address, or obtain information for generating a new care-of address and generate a new care-of address according to the information;

And a switching unit, configured to perform network layer switching by using the new handover address when receiving an indication that network layer handover is required.

The embodiment of the present invention further provides a terminal, including a receiving unit, further comprising: an acquiring unit, configured to acquire a new care-of address, or obtain information for generating a new care-of address and generate a new care-of address according to the information;

And a switching unit, configured to perform network layer switching by using the new care-of address when the receiving unit receives an indication that network layer handover is required.

The foregoing technical solution can be seen that, before the terminal receives the indication that the network side needs to perform network layer handover, that is, the terminal generates a new care-of address for the terminal or provides the terminal for the terminal before performing the network layer handover. The information of the new care-of address is generated, and then the network switch is performed by using the new care-of address or the new care-of address generated by the terminal. Compared with the prior art, the embodiment of the present invention avoids the configuration of the terminal when performing network layer handover. The delay caused by the new care-of address or the information used to generate the new care-of address, thereby reducing the handover delay of the terminal at the network layer, thereby reducing the overall handover of the terminal from one access router to another access router. Delay.

DRAWINGS

1 is a schematic diagram of a prior art WiMAX network;

2 is a flow chart of network layer switching in prior art 1;

3 is a flowchart of a network layer handover of the prior art 2; 4 is a flowchart of a method for shortening a handover delay according to Embodiment 1 of the present invention;

5 is a flowchart of a method for shortening a handover delay according to Embodiment 2 of the present invention;

6 is a schematic diagram of a system for shortening a handover delay according to Embodiment 3 of the present invention;

Figure Ί is a schematic diagram of a system for shortening handover delay according to Embodiment 4 of the present invention;

8 is a schematic diagram of a terminal according to Embodiment 5 of the present invention;

FIG. 9 is a schematic diagram of a terminal according to Embodiment 6 of the present invention.

detailed description

The embodiments of the present invention provide a method and a system for shortening the handover delay. The technical solutions of the embodiments of the present invention are described in detail below with reference to the accompanying drawings.

Embodiment 1

This embodiment describes how to reduce the network layer switching network layer handover delay caused by terminal mobility. Network layer switching delay = network layer mobility detection delay + new care-of address configuration delay + MIP binding update delay, if the network layer mobility detection delay, the new care-of address configuration delay and MIP tie are respectively reduced The update delay is delayed, which reduces the handover delay of the terminal at the network layer.

The delay caused by the terminal mobility causing the network layer handover can be reduced by reducing the network layer mobility detection delay and the new care-of address configuration delay, and avoiding the MIP binding update delay. When the terminal moves, the network layer firstly passes through the air interface link layer switching process of the terminal itself. During the air interface link layer switching process, the network side configures a new care-of address for the terminal and performs DAD detection on the new care-of address. This prevents the terminal from configuring the new care-of address and performing DAD detection on the new care-of address after the network layer switchover, thereby avoiding the delay caused by the configuration and collision detection of the new care-of address. In addition, the terminal does not need to detect whether there is a new AR sending router broadcast message to perform network layer mobility detection, but the handover indication initiated by the network side informs the terminal whether network layer handover is needed, thereby avoiding network layer mobility. The delay caused by the detection of the sex also avoids the problem of mis-migration caused by the terminal connecting multiple ARs. Finally, the terminal continues to use the old care-of address to maintain the original IP service connection before the MIP binding update is completed. After the terminal re-enters the network under the new AR, the MIP binding can be sent and received before the MIP binding update, thus avoiding the MIP binding. Update the issue of latency.

Referring to FIG. 4, FIG. 4 is a flowchart of Embodiment 1 of the present invention. The implementation manner is a network layer handover caused by terminal mobility, and specifically includes the following steps: Step 401: The terminal acquires a base station identifier (BSID, Base Station Identifier) of one or more neighboring base stations by using a territorial broadcast message (MOB_NBR-ADV) sent by the serving base station SBS, and forms the base station identifiers into a base station identifier list.

In addition, the terminal may obtain a Base Station Identifier (BSID) of one or more neighboring base stations through a Scanning process, and form the base station identifiers into a base station identifier list.

Step 402: The terminal searches the obtained neighboring base station identifier list to save the AR information of the ASN-GW connected to the base station. If yes, the terminal continues to save the corresponding access router information, otherwise, sends a message to the anchor ASN-GW, requesting If the AR information of the one or more base stations is required, step 403 is performed. For example, the terminal sends a router request proxy (RtSolPr, Router Solistation Proxy) message to the anchor ASN-GW to request the required AR information of one or more base stations. , where the RtSolPr message carries a list of BSIDs that require a request.

Step 403: After receiving the router requesting proxy message of the terminal, the anchor ASN-GW informs the terminal of the requested AR information, or the anchor ASN-GW periodically informs the terminal of the information of the neighboring AR. The AR information of the anchor ASN-GW may be pre-configured or previously obtained. For example, if the anchor ASN-GW has the AR information, the anchor ASN-GW sends a proxy router broadcast message (PrRtAdv, Proxy Router Advertisement) to the terminal, and carries the AR information requested by the terminal in the PrRtAdv message; if the anchor ASN-GW does not have For these AR information, the anchor ASN-GW also needs to obtain these AR information through the assistance of other entities on the network side, and then inform the terminal. The AR information includes one or more of a link layer address, an IP address, and a network prefix of the AR interface connected to the BS.

Step 404 to step 406, the terminal initiates a handover request (MOB MSHO-REQ) message to the serving base station (SBS, Serving BS), and the message is sent to the anchor ASN-GW through the SBS and the serving ASN-GW, where the handover request message is sent. Includes one or more target base stations (TBS, Target BS) lists.

Step 407: The anchor ASN-GW sends a handover request message to all the candidate target ASNs. If the anchor ASN-GW determines the network layer migration, the switch request message carries the NCoA address or the terminal local used to generate the NCoA address. Interface identifier.

Optionally, the embodiment of the present invention may also send a handover request message to all candidate target ASN-GWs by using the serving ASN-GW. If the service ASN-GW determines the network layer migration at this time, The handover request message carries an NCoA address or a terminal local interface identifier (IID, Interface ID) for generating an NCoA address.

Optionally, if the network layer migration is determined by the target ASN-GW, the target ASN-GW also needs to obtain an NCoA address or a terminal local interface identifier for generating an NCoA address from the anchor ASN-GW or the serving ASN-GW.

The NCoA address is an anchor ASN-GW or a serving ASN-GW or a target ASN-GW, and the network prefix of the local interface identifier and the target AR information of the terminal is generated by a standard stateless manner or a DHCP protocol or a mobile IP registration. The protocol has state generation.

Step 408 to step 409: The target ASN-GW sends a handover request message to the TBS, and then the TBS sends a handover response (MOB_BSHO-RSP) message to the target ASN-GW.

Step 410: After receiving the handover response message, the target ASN-GW performs address conflict detection according to the NCoA address carried in the request message, and carries the detection result in the handover response message to notify the anchor ASN-GW. If the address conflicts, indicating that the NCoA is used in the target ASN-GW, the target ASN-GW reassigns the new care-of address NCoA', and sends the NCoA to the anchor ASN-GW through the handover response message, if the address does not occur. The collision carries the NCoA to the anchor ASN-GW through the handover response message.

In addition, in order to ensure data integrity, the anchor ASN-GW can pre-establish the data channel (DP, data-path) with the target ASN-GW at this stage. After the DP is established, the anchor ASN-GW does not immediately go to the target ASN- The GW sends the data packet, and the current data packet continues to be sent to the serving ASN-GW.

Step 411 to step 413: The anchor ASN-GW sends a handover response message to the terminal through the serving ASN-GW and the SBS.

In addition, the serving ASN-GW sends a handover response message directly to the terminal through the SBS.

Step 414: The terminal sends a handover indication (MOB_HO-IND) message to the SBS. If the handover indication message does not carry any target base station identifier or explicitly indicates that the handover cancels or rejects the handover, step 415 is performed, if the terminal is in the handover indication message. If the selected TBS or the explicit handover indication information is carried, step 419 is performed.

Step 415: The SBS sends a handover cancel (HO-Cancel) message to the serving ASN-GW. Step 416 to step 418, the serving ASN-GW sends a handover cancel message to the TBS through the anchor ASN-GW and the target ASN-GW, and the SBS, the anchor ASN-GW, the target ASN-GW, and the TBS receive the handover. After canceling the message, release all resources allocated to the terminal before the handover preparation phase, such as pre-allocated

The NCoA address, etc., the switching process ends here.

Step 419: After receiving the handover indication message, the SBS sends a handover confirmation (HO-Confirm) message to the service ASN-GW.

Step 420: The serving ASN-GW sends a handover confirmation (HO-Confirm) message to the anchor ASN-GW, and the anchor ASN-GW stops forwarding data to the serving ASN-GW after receiving the handover confirmation message, and forwards the downlink data of the terminal to the target. ASN-GW, the target ASN-GW caches all data of the terminal.

After receiving the handover confirmation message, the anchor ASN-GW sends a network layer handover indication FBack message to the terminal, where the message carries a network layer handover indication. The terminal determines whether the message carries a new care-of address or information for generating a new care-of address. If the message does not carry a new care-of address or information for generating a new care-of address, the terminal receives the network layer handover indication message. ^^ The NCoA address is generated stateless according to the AR information connected to the previously saved TBS. The stateless generation of the NCoA address refers to the generation of the NCoA address according to the specified method by using the AR information and the information of the terminal itself. Generally, the NCoA is generated according to the network prefix of the AR information and the local link interface identifier of the terminal, and the terminal generates the NCoA. The NCoA and the anchor ASN-GW are the same as the NCoA generated by the terminal. Therefore, the NCoA address generated by the terminal and the anchor ASN-GW are the same as the NCoA address generated by the terminal and requested to be DAD.

Before this, the FSH message needs to be sent to the serving ASN-GW and the target ASN-GW at the same time, and the serving ASN-GW and the target ASN-GW respectively send FBack messages to the SBS base station and the TBS to prevent the mobile terminal from moving too fast. Go to the target network and re-enter the network.

Step 421 to step 422: The anchor ASN-GW sends a HO-Confirm message to the target ASN-GW, and the target ASN-GW sends a HO-Confirm message to the TBS.

Optionally, the handover confirmation message is sent to the target ASN-GW directly through the serving ASN-GW. Step 423: The terminal moves to the TBS to perform network re-entry, and establishes a link layer connection.

Step 424: Optionally, after the terminal performs network re-entry, the target ASN-GW determines that the network layer handover needs to be performed or receives an indication that the network layer handover is to be performed, or the target ASN-GW has not received the network from the terminal before. A layer connection indication message, such as a Fast Neighbor Advertisement (FNA) message, or a network layer connection indication message is received but the terminal needs to re-allocate the CoA, and the AR in the target ASN-GW actively sends a router broadcast message to inform the terminal. The AR served for it has changed, in which it carries an indication that network layer handover is required, and may also carry a new care-of address or target AR information for generating a new care-of address. If the terminal has not received the FBack message, the terminal performs step 425 after receiving the message, otherwise the route broadcast message may be ignored.

Step 425: The terminal needs to send a fast neighbor broadcast when performing network layer handover (FNA, Fast)

Neighbor Advertisement ) The message indicates that the target ASN-GW has sent the cached data, and the terminal continues to use the old care-of address (PCoA, Previous CoA) to send and receive data packets, and the network layer connection has been established.

Step 426: The terminal uses the new care-of address to perform the MIP rebinding. The binding process includes the MIP rebinding of the terminal and the HA, the binding update of the terminal and other CNs, and the completion of the MIP binding update CN or HA, that is, It can communicate with the new care-of address used by the terminal.

Step 427: After all the MIP binding updates are completed, the terminal sends an FNA message to the target ASN-GW or the anchor ASN-GW, indicating that the MIP binding update is completed, and the target ASN-GW or the anchor ASN-GW initiates the target ASN-GW and The data channel tunnel release process of the R4 between the anchor ASN-GW, maintaining the terminal-related context, and thus the fast mobile IP handover process is completed.

Embodiment 2

This embodiment describes how to reduce the network layer switching delay in network layer handover caused by network resource optimization. Similarly, network layer handover delay = network layer mobility detection delay + NCoA address configuration delay + MIP binding update delay, if network layer mobility detection delay, NCoA address configuration delay, and MIP binding update are respectively reduced Delay, then it will reduce the switching delay of the entire network layer.

The network layer switching caused by network resource optimization reduces the network layer handover delay by reducing the network layer mobility detection delay and the NCoA address configuration delay, and avoiding the MIP binding update delay. When the network layer is switched, the terminal does not move, and there is no link layer handover process. Therefore, before the network layer initiates the network layer handover, the network side entity needs to interact and actively configure the terminal in the service ASN-GW. The NCoA to be used, and the DAD detection is performed in advance, thus avoiding the delay caused by the configuration of the NCoA address and the DAD detection when the network layer switching occurs; in addition, the network layer switching caused by the network resource optimization is initiated by the network side. No need for the terminal to perform network layer mobility detection by detecting whether a new AR sends a router broadcast message, but prepares on the network side. After the NCoA, the handover indication initiated by the network side informs the terminal that the network layer handover needs to be initiated, thereby reducing the total network layer handover delay and avoiding the mis-migration problem caused by the terminal connecting multiple ARs. At the same time, the terminal continues to use the old CoA address to maintain the original IP service connection before the MIP binding update is completed. After the terminal re-enters the network in the new AR, the terminal can send and receive data before the MIP binding update is completed, thus avoiding the MIP. Bind the issue of update latency.

Referring to FIG. 5, FIG. 5 is a flowchart of Embodiment 2 of the present invention. The implementation manner is a network layer handover caused by network resource optimization, and specifically includes the following steps:

Step 501: The anchor ASN-GW prepares to perform network layer switching caused by network side resource optimization. In this step, the service ASN-GW is ready to perform network layer handover, and the service ASN-GW sends a network layer handover request message to the anchor ASN-GW to request network layer handover.

Step 502: The anchor ASN-GW sends a message to the serving ASN-GW, where the message carries an indication that the network layer handover needs to be performed, and a new care-of address or a terminal local interface identifier used to generate a new care-of address.

Optionally, the anchor ASN-GW receives the network layer handover request message from the serving ASN-GW, and then sends an indication to the serving ASN-GW that the network layer handover needs to be performed, and the new care-of address or the terminal used to generate the new care-of address. The message identified by the local interface.

Step 503: The service ASN-GW receives the handover indication message, and directly generates the NCoA for the terminal according to the stateless address generation mode by using the new care-of address provided by the anchor ASN-GW or the network prefix and the received IID information according to the subnet. And performing DAD detection; if the new service ASN-GW does not allow the use of a stateless address to generate a care-of address or address conflict, the serving ASN-GW re-assigns the NCoA to the terminal.

Step 504: The serving ASN-GW sends a handover response (R3_Relocation.Rsp) message to the anchor ASN-GW.

Step 505: The serving ASN-GW sends an RA message to the terminal, and informs the terminal of the new AR information, where the message carries the network layer handover indication, the new care-of address or the AR information used to generate the new care-of address, and whether the new care-of address has been completed. An indication of DAD detection. There is no sequence relationship between step 504 and step 505.

Step 506: The terminal initiates a MIP binding update message, and completes binding with the HA or other CN. New process. Before all binding updates are completed, the terminal still uses the PCoA address, and the CN that has not been bound and updated still uses the PCoA address for communication, and the CN that has been bound and updated can communicate using the NCoA address.

Step 507: The HA sends a message to the terminal to confirm that the binding update is completed.

Step 508: The terminal releases the old care-of address and the context associated with the address, and the anchor

The ASN-GW or the service ASN-GW sends an FNA message indicating that the MIP binding update has been completed. The FNA message encapsulation carries a Fast Binding Updata (FBU) message indicating the binding lifetime=0.

Step 509: After receiving the FNA message, the anchor ASN-GW or the serving ASN-GW initiates an R4 tunnel release process between the anchor ASN-GW and the serving ASN-GW, and the fast mobile IP handover process is completed.

It can be seen from the above two embodiments that the new care-of address carried in the handover request is generated by the network side by a standard stateless method instead of the terminal. In addition, the new care-of address configured for the terminal can be generated in a stateful manner, such as by way of a DHCP protocol or a Mobile IP registration protocol to generate a new care-of address.

Embodiment 3

According to the method embodiment of the network layer handover caused by the terminal mobility, the third embodiment of the present invention provides a system for shortening the handover delay. As shown in FIG. 6, the system includes the terminal 601 and the network side device 602.

The terminal 601 is configured to acquire the neighboring base station identifier, and retrieve whether the neighboring base station identifier has the AR information connected thereto, and send the AR information required for the message request to the network side device 602 when there is no AR information connected thereto; For example, the Router Request Broker (RtSolPr, Router Solistation Proxy) message is used to obtain an AR message, where the RtSolPr message carries a BSID list.

The terminal 601 acquires a new care-of address from the network-side device 602, or acquires information for generating a new care-of address from the network-side device 702, such as access router information, and generates a new stateless manner according to the information for generating a new care-of address. The care-of address, and the network layer switching is performed by using the new care-of address when receiving an indication that the network side device 602 needs to perform network layer handover.

The network side device 602 includes:

The anchor accesses the monthly network gateway 603, and is configured to generate a new care-of address for the terminal 601, and then send a handover request message carrying the new care-of address to the target access service network gateway 604. Usually, the anchor access service The network gateway 603 generates a new care-of address in a standard stateless manner according to the network prefix of the terminal 601 local interface identifier and the AR information. In addition, the NCoA address configured for the terminal can be generated in a stateful manner, for example, through a dynamic host configuration protocol ( DHCP, Dynamic Host Configuration Protocol) or Mobile IP Registration Protocol has a state to generate a new care-of address.

The target access service network gateway 604 is configured to perform address conflict detection on the new care-of address sent by the anchor access service network gateway 603, and send the new care-of address and the indication that needs to perform network layer handover when the address does not conflict. The terminal 601, and when the address conflicts, re-assigns the new care-of address to the terminal 601, and then transmits the newly-assigned new care-of address and the indication that network layer handover is required to the terminal 601.

In this embodiment, the anchor access service network gateway 603 generates a new care-of address, and in addition, the addressable access router information and the terminal 601 information, and the target access service network gateway 604 reuses the anchor access service network gateway. The information provided by 603 generates a new care-of address in a stateless manner. In addition, the terminal can be directly assigned a new care-of address through a Dynamic Host Configuration Protocol or a Mobile IP Registration Protocol.

Embodiment 4

According to the method embodiment of the network layer switching caused by the network resource optimization, the fourth embodiment of the present invention also provides a corresponding system. As shown in FIG. 7, the system includes a terminal 701 and a network side device 702.

The terminal 701 includes information for acquiring a new care-of address from the network-side device 702, or acquiring information for generating a new care-of address from the network-side device 702, for example, access router information, and then generating a new care-of address. The information generates a new care-of address in a stateless manner, and performs network layer switching using the new care-of address when receiving an indication sent by the network-side device 702 that a network layer switch is required.

The network side device 702 includes:

The anchor access service network gateway 703 is configured to send an indication to the service access service network gateway 704 that a network layer handover is required and terminal 701 information for generating a new care-of address, such as an interface identifier (IID).

The service access service network gateway 704 is configured to generate a new care-of address for the terminal 701 according to the information of the terminal 701, and perform address conflict detection on the new care-of address, and when the address does not conflict, the The new care-of address is sent to the terminal 701, and the new care-of address is re-allocated to the terminal 701 when the address conflicts, and the re-allocated address is sent to the terminal 701, or the access router information for generating the new care-of address is transmitted to the terminal 701. . The service access service network gateway 703 generates a new care-of address in a standard stateless manner according to the local interface identifier of the terminal 701 and the network prefix of the AR information. In addition, the new care-of address configured for the terminal can be generated in a stateful manner. The new care-of address is obtained, for example, through a Dynamic Host Configuration Protocol or a Mobile IP Registration Protocol.

In addition, the service access service network gateway 704 sends a message carrying the new care-of address to the anchor access service network gateway 703, and sends an RA message to the terminal 701 to inform the terminal of the new AR information, where the message carries the network layer handover. An indication of whether the indication, the new care-of address, and the new care-of address have completed DAD detection.

Similarly, this embodiment can also generate a new care-of address by the anchor access service network gateway 703.

The detailed process of performing the network layer switching by the system for shortening the handover delay of this embodiment is consistent with the description in the foregoing method of the embodiment of the present invention, and will not be further described herein.

Embodiment 5

The embodiment of the present invention also provides a terminal. As shown in FIG. 8, the terminal includes an obtaining unit 801, a switching unit 802, and a releasing unit 805.

The obtaining unit 801 is configured to acquire a new care-of address, or obtain information for generating a new care-of address and generate a new care-of address according to the information.

The switching unit 802 includes:

The receiving unit 803 is configured to receive an indication that a network layer handover is required.

The binding unit 804 is configured to use the new care-of address obtained or generated by the obtaining unit 801 to perform binding update when receiving the indication that the network layer handover is required, and use the old handover before performing the mobile internet protocol binding. The address establishes a connection at the network layer.

The releasing unit 805 is configured to release the context corresponding to the old care-of address and the old care-of address after the binding unit 804 is updated.

The embodiment of the present invention further provides a terminal. As shown in FIG. 9, the terminal includes a receiving unit 901, an obtaining unit 902, and a switching unit 903. The terminal further includes a storage unit 904 and a releasing unit 905.

The receiving unit 901 is configured to receive a message from the network side, and the acquiring unit 902 is configured to acquire a new care-of address according to the message received by the receiving unit 901, or obtain a new care-of address for generating a new care-of address. And generating a new care-of address according to the information; the switching unit 903 is configured to perform network layer handover by using the new care-of address when the receiving unit 901 receives an indication that the network layer handover is required.

The storage unit 904 is configured to store neighbor access router information, including the physical address of the router port, the network prefix and the IP address. The obtaining unit 902 may acquire the information for generating a new care-of address from the storage unit 904; or obtain the information for generating a new care-of address from a message received by the receiving unit 901.

In order to complete the network layer switching, the switching unit 903 includes: a binding unit 9031, configured to perform binding update by using the new care-of address; and a connection establishing unit 9032, configured to use the old handoff before the binding unit 9031 performs binding update. The address establishes a connection at the network layer.

After the binding unit 9031 completes the binding update, the release unit 905 releases the old care-of address and the context corresponding to the old care-of address.

The AR information in the foregoing embodiments refers to one or more pieces of link layer address, IP address, and network prefix of the AR interface connected to the BS.

According to the embodiment of the foregoing method and system, before the terminal receives the network layer handover indication sent by the network side, the network side generates a new care-of address for the terminal or provides the terminal with information for generating a new care-of address. Then, the network layer switching is performed by using the new care-of address sent by the network side or the new care-of address generated by the terminal. Compared with the prior art, the embodiment of the present invention prevents the terminal from configuring a new care-of address or acquiring for the network layer handover. The delay caused by the information of the new care-of address is generated, so that the handover delay of the terminal at the network layer can be reduced, thereby reducing the entire handover delay of the terminal from one access router to another access router.

Further, in the embodiment of the present invention, the terminal performs DAD detection on the generated new care-of address before performing network layer handover, thereby avoiding the delay caused by the address conflict detection, thereby reducing the handover delay of the terminal at the network layer. .

Further, the terminal of the embodiment of the present invention does not need to detect whether there is a new AR sending router broadcast message to perform network layer mobility detection, but the switching indication initiated by the network side notifies the terminal whether network layer switching is required, thereby The delay caused by the network layer mobility detection is avoided, thereby reducing the handover delay of the terminal at the network layer, and also avoiding the problem of mis-migration caused by the terminal connecting multiple ARs.

Further, since the terminal of the embodiment of the present invention continues to use the old handover before the MIP binding update The address maintains the original IP service connection, so that after the terminal re-enters the network under the new AR, the MIP can send and receive data before the binding is updated, thereby avoiding the problem of MIP binding update delay, thereby reducing the terminal at the network layer. Switch delay.

Further, the embodiment of the present invention sends the message to the target base station and the serving base station before sending the network layer handover indication message to the terminal, where the message carries an indication that network layer handover needs to be performed, and a new care-of address or is used for The access router information of the new care-of address is generated, so that the terminal can receive an indication that network layer handover is required when the terminal moves.

Finally, after the MIP binding update is completed, the terminal also sends an FNA message to the network side to notify the access router that the binding update has been completed, so that the access router can perform subsequent processing after the binding update is completed. , such as resource release.

The foregoing detailed description of the method, system, and terminal for shortening the handover delay provided by the embodiments of the present invention is only for helping to understand the technical solution of the present invention. Meanwhile, for those skilled in the art, according to the present invention, The present invention is not limited by the scope of the present invention.

Claims

Rights request

A method for shortening a handover delay, the method comprising:

The terminal performs network layer switching by using a new care-of address generated by itself or the new care-of address generated by the network side.

2. The method for shortening a handover delay according to claim 1, wherein the message sent by the network side further comprises: information for generating a new care-of address;

The method further includes the terminal generating a new care-of address based on the information used to generate the new care-of address.

3. The method of shortening a handover delay according to claim 1, wherein the method further comprises:

The terminal generates a new care-of address in a stateless manner according to the acquired access router information and its own information.

The method for shortening the handover delay according to claim 3, wherein the obtaining, by the terminal, access router information comprises:

The terminal sends an access router information request to the network side, where the request carries one or more base station identifiers;

The terminal receives access router information that is connected by the base station and sent by the network side.

The method for shortening handover delay according to claim 3, wherein the access router information comprises one or any combination of the following: a link layer address, an IP address, and an interface of an interface connecting the base station, Network prefix.

6. The method of shortening a handover delay according to claim 1, wherein the method further comprises:

The network side generates a new care-of address for the terminal according to the terminal local interface identifier.

7. The method of shortening a handover delay according to claim 1, wherein the method further comprises:

The network side generates a new care-of address for the terminal; The network side performs address conflict detection on the new care-of address;

When the new care-of address has been used in the network, a new care-of address is generated for the terminal.

8. The method of shortening handover delay according to claim 7, wherein:

The address is used for address conflict detection.

The method for shortening the handover delay according to claim 1, wherein the receiving the message sent by the network side before the terminal further comprises:

The terminal sends a handover request to the network side;

The anchor access service network gateway or the service access service network gateway on the network side sends a handover request to all the candidate target access service network gateways, where the handover request carries the new care-of address generated by the network side for the terminal or is used for Generates the terminal local interface ID of the new care-of address.

The method for shortening the handover delay according to claim 9, wherein the receiving the message sent by the network side before the terminal further comprises:

The terminal sends an indication carrying handover rejection or handover cancellation to the network side, and each entity on the network side releases all resources allocated for the terminal; or

The terminal sends an indication that does not carry handover rejection or handover cancellation to the network side, and the network side caches all the service data of the terminal.

The method for shortening the handover delay according to claim 10, wherein before the receiving the message sent by the network side, the terminal further includes:

The anchor access network gateway on the network side sends an indication to the target base station and the serving base station that network layer handover is required, as well as a new care-of address or information for generating a new care-of address.

12. The method of shortening a handover delay according to claim 1, wherein the method further comprises:

After the terminal switches to the target network, it sends a network layer connection indication to the target access service network gateway, where the indication carries the new care-of address that the terminal will use for network layer handover.

The method for shortening the handover delay according to claim 1, wherein the method further comprises: The target access service network gateway sends a router broadcast message to the terminal to inform the terminal that the access router served by the terminal has changed. The router broadcast message carries an indication that network layer handover needs to be performed, or carries an indication that network layer handover needs to be performed. And a new care-of address or information used to generate a new care-of address.

The method for shortening a handover delay according to any one of claims 1 to 13, wherein the terminal performs network layer handover by using a new care-of address generated by itself or the new care-of address generated by the network side. :

The terminal uses the new care-of address for binding updates and establishes a network layer connection using the old care-of address before the binding update is completed.

The method of shortening a handover delay according to claim 14, wherein the method further comprises:

After completing the network layer handover, the terminal releases the context related to the old care-of address and the old care-of address, and sends a binding update completion indication to the network side;

The network side releases the associated data channel and context.

The method for shortening the handover delay according to claim 15, wherein the method further comprises:

The cached data is sent to the terminal before the network side releases the associated data channel and context.

17. A system for shortening handover delay, characterized in that it comprises:

a network side device, configured to generate a new care-of address for the terminal, and send an indication to the terminal that a network layer handover is required, and a new care-of address or information for generating a new care-of address; and

18. The system for shortening handover delay according to claim 17, wherein the network side device comprises:

The anchor accesses the service network gateway, and is configured to generate a new care-of address for the terminal, and send the new care-of address, or provide terminal information and access router information for generating a new care-of address; The target access service network gateway is configured to perform address conflict detection on the new care-of address sent by the anchor access service network gateway, or generate a new care-of address according to the terminal information and access router information provided by the anchor access service network gateway, The address is used for collision detection. When the address does not conflict, the new care-of address and the indication for performing network layer handover are sent to the terminal. When the address conflicts, the terminal is assigned a new care-of address and the new address is added. The newly assigned care-of address and the indication that the network layer handover needs to be performed are sent to the terminal.

The system for shortening the handover delay according to claim 17, wherein the network side device comprises:

The anchor accesses the service network gateway, and is configured to send an indication that needs to perform network layer handover, and terminal information and access router information used to generate a new care-of address;

The service access service network gateway is configured to generate a new care-of address for the terminal according to the terminal information and the access router information sent by the anchor access service network gateway, and perform address conflict detection on the new care-of address; when the address does not conflict Sending the new care-of address and the indication that the network layer needs to be handed over to the terminal; when the address conflicts, re-assigning the new care-of address to the terminal, and reassigning the new care-of address and the network layer that needs to be performed The indication of the handover is sent to the terminal.

20. A terminal, comprising:

The terminal according to claim 20, wherein the switching unit comprises: a receiving unit, configured to receive an indication that a network layer handover is required;

a binding unit, configured to use the new care-of address to perform binding update when the receiving unit receives an indication that a network layer handover is required, and establish a network layer by using an old care-of address before performing mobile internet protocol binding Connection.

The terminal according to claim 20 or 21, wherein the terminal further comprises: a releasing unit, configured to release the old care-of address and the context corresponding to the old care-of address after the binding unit update is completed.

A terminal, comprising a receiving unit, further comprising: An obtaining unit, configured to acquire a new care-of address, or obtain information for generating a new care-of address and generate a new care-of address according to the information;

The terminal according to claim 23, wherein the terminal further comprises: a storage unit, configured to store neighboring access router information, including a physical address of the router port, a network prefix and an IP address;

The obtaining unit acquires the information for generating a new care-of address from the storage unit; or acquires the information for generating a new care-of address from a message received by the receiving unit.

The terminal according to claim 23, wherein the switching unit comprises: a binding unit, configured to perform binding update by using the new care-of address;

The connection establishing unit is configured to establish a connection of the network layer by using the old care-of address before the binding unit performs the binding update.

The terminal according to any one of claims 23 to 25, wherein the terminal further comprises:

a release unit, configured to release the old care-of address and the context corresponding to the old care-of address after the binding unit update is completed.