WO2009030152A1

WO2009030152A1 - Method, system and appratus for implementing mobile handover

Info

Publication number: WO2009030152A1
Application number: PCT/CN2008/072158
Authority: WO
Inventors: Xiaoyu Gong; Xianzhen Yang
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2007-08-28
Filing date: 2008-08-27
Publication date: 2009-03-12
Also published as: CN101378588B; CN101378588A

Abstract

The invention discloses a method for implementing mobile handover. Therein when the MN, which has finished the initial attachment in the access network domain, needs to carry out a mobile handover in current access domain, the method includes: selecting a target access router (N-AR) in current access network domain; pre-establishing a connection with the selected N-AR, and modifying the initial attachment information in the process of pre-establishing the connection; completing the process of pre-establishing a connection and performing handover as well as releasing the resources of the previous point of attachment. The embodiment of the invention discloses a system and apparatus for implementing mobile handover at the same time. Seamless handover can be achieved in NGN architecture by adoption of the method, system and apparatus disclosed by the embodiment of the invention.

Description

Method, system and device for realizing mobile switching

The present invention relates to a mobile handover (Handover) technology, and more particularly to a method, system and apparatus for implementing mobile handover in a next generation network. Background technique

The structure of the Next Generation Network (NGN) is defined in the International Telecommunication Union Telecommunication Standardization Sector (ITU-T), which is divided into three layers: the Service Control Layer (SCF), the Transmission Control Layer, and the Transport Layer. Figure 1 is a schematic diagram of the composition of an SCF in an existing NGN architecture. The SCF is mainly composed of a Proxy Call Session Control Function Entity (P-CSCF), a Serving Call Session Control Function Entity (S-CSCF), and a Home Subscriber Server (HSS). Figure 2 is a schematic diagram of the composition of the transport control layer in the existing NGN architecture. The transport control layer mainly includes a network attach control function entity (NACF) and a resource admission control function entity (RACF). The main functional entities included in NACF are as follows: Access Management Function Entity (AM-FE), Transport Layer Authentication Authorization Function Entity (TAA-FE), Transport Layer User Configuration Library Functional Entity (TUP-FE), Network Address Configuration Function Entity ( NAC-FE) and Transport Layer Location Management Functional Entity (TLM-FE). The functional entity mainly included in the RACF is the Policy Decision Function Entity (PD-FE). In practical applications, the problem of moving nodes in the network is often involved. The existing NGN architecture can support a mobile scene, Nomadism, to move the mobile node (MN) from its original location to a new location. However, this method needs to interrupt the original business session during the mobile process, and then re-establish the session after moving to a new place. Obviously, this mobile mode causes inconvenience to the normal development of the service. Therefore, it is desirable to realize the mobile switching in the NGN by means of the existing mobile switching mode applied in other environments, and achieve the purpose of not interrupting the original service or even seamlessly switching.

Currently, there are two main types of mobile handover protocols, one is a SIP-based handover protocol, and the other is a handover protocol based on the Mobile Internet Protocol (MIP). In order to reduce the delay and packet loss of mobile switching, the Internet Engineering Task Force (IETF) has developed a number of mobile standards, such as Fast MIP (FMIP), Hierarchical MIP (HMIP), and Joint MIP (SMIP). Agent MIP (PMIP) and so on.

In the process of implementing the present invention, the inventors have found that existing methods have at least the following disadvantages:

Although the above various handover protocols can achieve uninterrupted mobile handover or even seamless handover to some extent, these handover protocols are only applicable to the Internet mode technology, and do not consider the transport layer and transmission control in the NGN. How to implement handover in the architecture separated by the layer and the service control layer, therefore, the existing handover protocol cannot be simply applied to the NGN architecture. Summary of the invention

Embodiments of the present invention provide a method for implementing mobile handover, which can implement seamless handover within an access network domain in an NGN architecture.

Embodiments of the present invention provide a system for implementing mobile handover, which can implement seamless handover within an access network domain in an NGN architecture.

The embodiment of the invention provides an L-NACF, and the L-NACF can implement seamless handover in the access domain in the NGN architecture.

The embodiment of the invention provides an H-NACF, and the H-NACF can implement seamless handover in the access domain in the NGN architecture.

The embodiment of the invention provides an AM-FE, and the AM-FE can implement seamless handover in the access domain in the NGN architecture.

The technical solution of the embodiment of the present invention is implemented as follows:

A method for implementing mobile handover, when an initial attached mobile node MN has been completed in an access network domain, and needs to be handed over from the current access router P-AR to the target access router N-AR within the access domain, The method includes:

Select the target access router N-AR in the access domain;

Performing connection pre-establishment on the selected N-AR, and modifying the initial attachment information during the connection pre-establishment process;

After the connection pre-establishment is completed, the handover is performed, and the resources of the current access router P-AR are released. A system for implementing mobile switching, the system comprising: a mobile node MN and an NGN a network; the NGN network includes a transport layer control management system located in the core network domain and the access network domain;

The transport layer control management system is configured to access the access network to complete the initial attach; when the MN needs to switch from the current access router P-AR to the target in the access domain When the router is in the N-AR, the target access router N-AR is selected in the access domain, the connection pre-establishment is performed on the selected N-AR, and the initial attachment information is modified in the connection pre-establishment process, and After the connection pre-establishment is completed, the handover is performed to release the resources of the current access router P-AR.

A local network attachment control function entity L-NACF, the L-NACF includes a local mobility management function entity L-MMF of the access domain; the L-MMF further includes: local handover management of the access domain Functional entity L-HMF and local location management function entity L-LMF of the access domain;

The L-HMF is configured to query the candidate AR information in the home network attachment control function entity H-NACF and the neighboring access point L2 detection information reported by the mobile node MN, and select the target access according to the configured selection policy. a router N-AR, which sends the address information of the N-AR to the MN; and instructs the access point mobility management function entity AM-FE to establish a media stream tunnel during the tunnel pre-establishment and execution handover;

The L-LMF is configured to perform location binding update under the indication of the AM-FE. A home network attachment control function entity H-NACF, where the H-NACF includes a mobility management function entity H-MMF of the core domain; the H-MMF further includes: a mobile switching management entity H- of the core domain HMF and core domain home location management function entity H-LMF;

The H-HMF is configured to query, according to the current attachment point physical point information of the current attachment point obtained from the local network attachment control function entity L-NACF, candidate AR information applicable to the mobile handover around the current attachment point;

The H-LMF is configured to save and bind the attachment information provided by the L-NACF. An access management function entity AM-FE, the AM-FE further comprising an access mobility management function entity A-MMF; the A-MMF specifically includes an access attachment point location management function entity A-LMF, and Ingress point control function entity A-ACF and access Attachment point media stream data forwarding function entity A-DTF;

The A-LMF, configured to send, according to the location and identity information of the mobile node MN, the mobile node MN to send a location binding or location update binding message to the local location management function entity L-LMF of the access domain;

The A-ACF is configured to send the Layer 2 L2 link state parameter and the trigger message of the MN to the local handover management function entity L-HMF of the access domain; and receive the L-HMF control instruction. , control L2 switching;

The A-DTF is configured to receive the L-HMF command, and establish a media flow tunnel between the current access router P-AR, the target access router N-AR, and the local anchor router A-AR.

It can be seen that, by using the technical solution of the embodiment of the present invention, the MN initially accesses the network, and completes an initial attach process in the access domain; when the mobile switch in the access domain needs to be performed, first performs N-AR discovery and selection. Then, the connection pre-establishment is performed on the selected N-AR; finally, the handover is performed, and the original attachment point resource is released. The solution of the embodiment of the present invention utilizes the characteristics of layering, fast, and packet loss of the existing handover protocol, and organically integrates with the hierarchical architecture of the NGN to implement seamless handover in the access domain in the NGN architecture. DRAWINGS

1 is a schematic diagram of the composition of an SCF in a service control layer in an existing NGN architecture; FIG. 2 is a schematic diagram of a composition of a transport control layer in an existing NGN architecture;

3 is a schematic diagram of a scenario of a mobile switching mode according to an embodiment of the present invention;

4 is a schematic diagram of an extended NGN architecture in an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of an extended AM-FE according to an embodiment of the present invention; FIG.

6 is a schematic structural diagram of an H-MMF according to an embodiment of the present invention;

7 is a flow chart of an embodiment of a method of the present invention;

FIG. 8 is a flowchart of initial attaching by a MN according to an embodiment of the present invention; FIG.

FIG. 9 is a flowchart of a MN performing full authentication of an initial attachment and establishing an SA according to an embodiment of the present invention;

FIG. 10 is a system on which an MN establishes an application layer service session according to an embodiment of the present invention; Schematic diagram

FIG. 11 is a flowchart of discovering and selecting an N-AR according to an embodiment of the present invention;

12 is a flowchart of establishing an N-AR pre-connection in an embodiment of a method according to the present invention; FIG. 13 is a schematic diagram of direct pre-authentication in an embodiment of the present invention;

14 is a schematic diagram of indirect pre-authentication in an embodiment of the present invention;

15 is a flowchart of implementing pre-authentication in an embodiment of the present invention;

16 is a flowchart of implementing location binding update and resource reservation in an embodiment of the present invention;

FIG. 17 is a schematic diagram of a RACF in a hierarchical structure according to an embodiment of the present invention; FIG. 18 is a flowchart of implementing pre-establishment of a tunnel in an embodiment of the present invention;

FIG. 19 is a flowchart of performing handover and releasing original attachment point resources in an embodiment of a method according to the present invention; FIG.

20 is a schematic structural diagram of a system embodiment of the present invention;

21 is a schematic structural diagram of a structure of an L-NACF according to an embodiment of the present invention;

FIG. 22 is a schematic structural diagram of a structure of an H-NACF according to an embodiment of the present invention. detailed description

The present invention will be further described in detail below with reference to the accompanying drawings.

First, some terms that will be used in the embodiment of the present invention are introduced:

(1) Domain and Access Domain

A domain is a concept of management scope. Each administrative domain has a unique domain name, which is used to identify the administrative domain to which a user belongs. You can use the "user ID + management domain ID, format, ^ port" user@home. Com".

A management domain further includes a core domain (Core Domain) and an access domain, and one core domain may correspond to multiple access domains; and each access domain may include multiple homogeneous or heterogeneous accesses. The access subnet of the technology may include multiple access attachment points in one access network domain, and each access attachment point may correspond to one access subnet. An access network domain is controlled by a local attachment control subsystem, and the MN is in the access network AN domain. When switching between access points, the media stream is switched by the anchor AR (A-AR) in the access domain, and the application layer session is not perceived.

The access domain and the core domain can belong to the same carrier or to different operators.

(2) Current Access Router (P-AR)

P-AR refers to the router (AR) where the MN is currently located at the access point, sometimes referred to as O-AR (Old-AR) or Serving (AR).

(3) Target Access Router (N-AR)

The router selected or designated by the MN to be moved to switch, also referred to as the target AR (Target AR )

(4) Access network domain anchor router A-AR

Within the scope of an access network, the A-AR has a local Home Agent function relative to the MN: The data media stream sent to the MN in the access domain needs to pass through the A-AR to reach the MN. The data media stream sent by the MN needs to be sent through the A-AR. The difference from the HA is that the A-AR is only the media stream forwarding point of the transport layer in the entire AN domain, and does not have the mobility management in the entire access domain. Features.

(5) Local home address (L-HoA) in the access domain

The L-HoA in the access domain is a HoA with local characteristics. When the MN moves within an access domain, the L-HoA is unchanged. Only after the MN moves out of the access domain, the L-HoA will Replaced; L-HoA will be used as the MN's SIP session address when establishing a service session at the application layer.

(6) Local care-of address (L-CoA) in the access domain

When the MN switches between ARs of different attachment points in an access domain, the address of each AR is selected as the L-CoA, and the IP-in-IP can be established between the A-AR and the attachment point AR by using this address. tunnel.

(7) Security Alliance (SA)

The SA only refers to the established security association relationship between the functional entities, such as the mutual trust relationship established between the MN and the DHCP server, AR or AAA Proxy entity; usually, the initial key is generated by both parties; Can effectively confirm the letter Whether the order or data comes from the other entity that has been securely authenticated, thus preventing the occurrence of such phenomena as theft or attack.

As shown in FIG. 3, it is a schematic diagram of a scenario of a mobile switching mode according to an embodiment of the present invention, where the MM1 mobile switching mode refers to mobile across the core network and across carriers; and the MM2 mobile switching mode refers to the same core network, but The mobility between the AN domains of different access networks is also referred to as the handover mode of the Inter-AN; the MM3 mobile handover mode refers to the mobility within the same access domain, also referred to as the Intra-AN handover mode. For both MM2 and MM3 switching modes, it is required to support the implementation of the handover without interrupting the ongoing service, and reduce the delay of the mobile handover during the handover process, and maintain minimal data loss, that is, seamless Switch. In Figure 3, CN is the core domain, AN1-1, and AN1-2 are two different access domains. Within each access domain, multiple access subnets of the same or different access technologies may be included.

In an embodiment of the present invention, when the MN that has completed the initial attachment in the access network domain needs to be handed over from the current access router P-AR to the target access router N-AR within the access domain: First, access The N-AR is selected in the domain, and the selected N-AR is pre-established and the initial attachment information is modified. After the connection pre-establishment is completed, the handover is performed, and the resources of the current access router P-AR are released.

To implement the above solution, you need to first add or extend some functional entities in the existing NGN architecture, as follows:

(1) Home Network Attachment Control Function Entity (H-NACF) and Local Network Attachment Control Function Entity (L-NACF):

FIG. 4 is a schematic diagram of an extended NGN architecture in an embodiment of the present invention. As shown in Figure 4, two levels of NGN attach control function entities, Home NACF and Local NACF, are referred to as H-NACF and L-NACF, respectively, in the core domain and the access domain.

The H-NACF is located in the core network and is a service subscription point. The original authentication data and the transport layer user configuration of the user network transport layer access are saved (User Profile M message; the user initially accesses the access network) In the domain, the user is fully authenticated (Full Authentication), and the subsequently generated SA and User Profile are sent to the L-NACF, so that the L-NACF performs fast pre-authentication on the Handover in the access domain (Fast In addition, the H-NACF can also query and deliver information about candidate ARs that can be used for the Handover around the current attachment point according to the physical identification information of the neighboring access point of the current attachment point reported by the L-NACF.

The L-NACF is used to manage the access attachment process of an access domain, implement mobility management control of the MN in the same access domain, configure an L-HoA address for the attached MN in the access domain, and access the L-HoA address in the access domain. The attached MN performs fast pre-authentication and temporarily suspends the user's transport layer User Profile in the local cache (Cache).

In addition to the above functions, H-NACF and L-NACF each have a hierarchical structure, and the current binding location information of the MN is saved. The L-NACF stores and binds the current location information of the MN in the access domain, including L3 logical location information (L3-CoA), L2 physical location information (L2 Physical Access ID), and L2 logical location information (L2 Logic). Access ID), optionally including geographic location information of the MN. The H-NACF saves and binds the address of the access domain where the MN is currently located, that is, the L-NACF location index. When the MN switches in the Intra-AN mode, only the location binding information of the L-NACF needs to be updated, and the binding location information in the H-NACF does not need to be updated; when the MN switches in the Inter-AN mode, the H-NACF The bound location information needs to be updated.

In this way, when the SCF needs to query the location information of the MN, it only needs to send a query request to the H-NACF, and the H-NACF further queries the corresponding L-NACF and obtains the MN in the access network according to the L-NACF location index of the MN. Detailed location information within the domain.

(2) Hierarchical media stream forwarding point A-AR and core network border gateway

(C-BGF):

In the embodiment of the present invention, a hierarchical media data stream forwarding point is introduced: an A-AR located in the access network domain and a C-BGF located in the core network domain.

The A-AR has a localized local proxy function. When the MN moves within the access domain, the outgoing and received media streams need to pass through the A-AR, and are transmitted through the bidirectional tunnel established by the A-AR and the AR of the attachment point. In an access domain, the A-AR can be statically configured or dynamically generated for different MNs. If it is statically configured, an A-AR is fixed for an access domain, and the address of the A-AR is used. Configure the AR and MN for the attachment point; if the dynamic configuration mode is used, then the MN attaches for the first time in the access domain. At the time, the AR of the first attachment point is dynamically selected by the access domain as the A-AR.

After the initial attachment is completed, the MN establishes a service session through the SIP message, which is selected by the SCF.

A C-BGF acts as the L3 input and output point for the media data stream between the access domain and the core domain. Correspondingly, the forwarding path of the media data stream is:

CN ~> C-BGF ~> A-AR ~> P-AR ~> MN ;

When intra-AN handover occurs, neither C-BGF nor A-AR will change, only P-AR will change; A-AR will change when Inter-AN handover occurs.

(3) Access Management Function Entity (AM-FE), Local Mobile Management Function Entity (L-MMF) of the access domain, and Mobile Management Function Entity (H-MMF) of the core domain: A, AM-FE:

The AM-FE is usually physically located on a physical device with the AR.

AM-FE is mainly used to implement DHCP Relay and PAA functions in the existing NGN architecture. The PAA function refers to the AAA Client function, that is, shielding specific access authentication to remotely authenticate dial-up user services (Radius) or extend Radius ( The protocol is forwarded to the AAA Server/Proxy in the L-NACF to implement the attach authentication process. The function of the embodiment is extended in the embodiment of the present invention, including: in the attach authentication, the SA required by the MN and the related entity is generated; Through the AM-FE interface with the neighboring AR, the pre-connection establishment information of the MN mobile handover is established, and the indirect pre-authentication and the address pre-allocation are implemented by the P-AR to the N-AR.

In order to support the mobility management, a sub-function entity, that is, an access mobility management function entity (A-MMF), is also introduced in the existing AM-FE. As shown in FIG. 5, FIG. 5 is an extended embodiment of the present invention. Schematic diagram of the composition of AM-FE. The A-MMF further includes an access point location management function entity (A-LMF), an access point control function entity (A-ACF), and an access point point media data stream forwarding function entity (A-DTF).

The A-LMF is configured to send a location binding, an update binding, and a debinding message to a local location management function entity (L-LMF) of the access domain according to the location and identity information of the MN; LMF generates and maintains a list of binding information for each MN, as shown in Table 1: A-LMF binding information list

The A-ACF is located between the L2 and the L3 of the access point; the L2 link state parameter and the trigger message of the MN are reported through the interface of the local handover management function entity (L-HMF) of the access domain, and the The L-HMF interface receives the L-HMF control command and controls the L2 switch. The related link parameters and other information are as follows:

Link parameters: low received signal strength, signal-to-noise ration, high frame error rate ...

Event: Link going down , handover completion...

Command: L2 Scan Handover Initiation , Committing...

The A-ACF can partially implement the MIH function specified in IEEE 802.12. For example, the MN and the access router know from the Link going down that the MN is about to be removed from the current attachment point range; similarly, according to the link information, the MN can automatically attach to the new The attachment point.

The A-DTF receives the command from the L-HMF, establishes or tears down the media stream IP tunnel between the P-AR, the N-AR, and the A-AR; the A-DTF is also responsible for mapping the L3 address of the media stream. Hit the L2 address of the client.

B, L-MMF:

The L-MMF in the access domain is a functional entity extended to support the intra-domain Handover, including the L-HMF and the transport layer location management function entity (TLM-FE) in the original NGN NACF with extended performance, now called L -LMF.

The L-HMF is the Handver management and decision point of the MN in the access domain; the Handover decision is made according to the L2 link information of the MN reported by the A-ACF; the L-HMF is also responsible for managing the current connection status of all the MNs in the access domain and In the mobile mode; in addition, the L-HMF is also the issuer of the Handover command, the Link layer event triggering policy is issued, the L2 control command is issued, the L3 media stream tunnel is established and removed, and the L3 switch is performed; The surrounding AR-availability information of the current attachment point that is queried by the core network domain or obtained from the local access domain and the L2 link scan detection information reported by the MN are combined with the local mobility management policy to determine the MN's new attachment. Point N-AR, and trigger the pre-authentication process and the context of the key (Context) transmission; subsequently, the L-HMF can also perform QoS resource query, reservation, etc. of the new attachment point through the interface with the RACF.

An interface with the A-LMF is added to the L-LMF. The A-LMF agent MN and the L-LMF exchange information related to the location binding update information LBU/LBA. The L-LMF is hierarchical with the home location management function entity (H-LMF) of the core domain.

The user-related information of the L-LMF binding is shown in Table 2:

Table 2 L-LMF binding information list

The same is true throughout the access domain;

For IPv6, this is tied to Home-Network-Prefix.

MN- Location: Information about the current location of the mobile node, where:

(L2 Logic Access L2 Logic Access ID: is every mobile node in

ID, access network L2 logical address in the AN domain, L2 logic

L2 Physical Access access information, for example: L2 layer link connection ID of the attachment point, port number, VLAN number, etc., mainly used for resources

L-CoA) admission control performs resource query on the bandwidth topology library.

L2 Physica Access ID: is the L2 physical address of each mobile node in the AN domain of the access network, for example: S S ID, B S ID, etc. of the physical device of the attachment point.

L-CoA: is the L3 address information of each mobile node in the access domain. It is the Care-of-address in the access domain, which is the address of the AR of the attachment point.

Access-Network-Type The access network type of the current attachment point. In the access network type, it includes access technologies for current access, such as Wi-Fi, Wimax, etc.

C, H-MMF:

The original H-LMF and the newly added Handover management entity H-HMF are included in the H-MMF. As shown in FIG. 6, FIG. 6 is a schematic diagram of the composition of the H-MMF in the embodiment of the present invention.

Among them, the H-HMF is the decision maker of the Handover transaction in the core network, the policy and the command issuer; and the query function of the AR information around the current attachment point: The interface with the L-HMF is used to obtain the current P-AR identifier. And by querying the Topologic Location Database and the Geography Location Database, the neighboring ARs are known, and then the information server is accessed. (Information Server) Query the information about these surrounding ARs and send them to L-HMF. If the network Topologic Location Database, Geography Location

Database and Information Server are configured in L-NACF, then the above process can also be done in L-HMF.

As a hierarchical user location management function, H-LMF provides the attachment information shown in Table 3 by L-LMF to bind:

H-LMF binding information list

Among them, L-LMF Addr can be used as an index to query further detailed location.

When the SCF needs to query the current location of the MN, use the L-HoA address or MN

The Identifier goes to the H-LMF lookup; the H-LMF queries the corresponding L-LMF according to the information of the binding, and obtains the detailed L2 physical/logical position information of the MN, and/or the L3 logical position information.

Based on the foregoing description, in the embodiment of the present invention, when the MN initially accesses the network, the initial attach process is first performed in the access network domain; after the initial attach is completed, at a certain time, when the MN needs to perform mobile handover, N-AR discovery and selection, and connection pre-establishment, binding update, resource admission control, and tunnel pre-establishment for the selected N-AR; finally performing handover to release the original attachment point resource.

The solution of the present invention will be further described in detail below by way of embodiments: Figure 7 is a flow chart of an embodiment of the method of the present invention. 4 The AM-FE and the AR in this embodiment are located on the same physical device. As shown in Figure 7, it includes:

Step s701: The MN initially accesses the network, performs an initial attach process in the access network domain, and establishes a SIP-based service session.

FIG. 8 is a flowchart of initial attaching by a MN according to an embodiment of the present invention, including: Step s801: The MN performs a full authentication process of initial attach, and establishes S A.

FIG. 9 is a schematic diagram of the MN performing initial authentication and establishing an SA in the embodiment of the present invention; Flow chart. As shown in Figure 9, it includes:

Step s901: The MN sends an Authentication Request message to the PAA in the AM-FE.

Steps s902 ~ s903: The PAA sends an AAA request message to the H-NACF through the L-NACF.

Step s904: The H-NACF performs authentication, and sends an AAA response message to the L-NACF.

After receiving the AAA request sent by the L-NACF, the H-NACF has its own AAA.

The server authenticates the MN according to the AAA-Key (MK) of the pre-stored MN, and sends an AAA response message to the L-NACF after the authentication is completed, which carries the primary session key (MSK) generated during the authentication process. ), generate the MSK random number Nonce and the MN's User Profile file.

Step s905: The L-NACF saves the User Profile file and the MSK carried in the AAA response message in the cache, and sends an AAA response message to the PAA in the AM-FE, where the MSK and the Nonce are carried, and the PAA obtains the MSK.

Step s906: The PAA sends an authentication response message to the MN, where the Nonce is carried. The MN generates the MSK based on the acquired Nonce and the pre-saved MK. Step s907: An MSK-based authentication relationship is established between the PAA and the MN.

The MSK can be used to build a Bootstrapping SA for subsequent Handovers.

Step s802: The L-NACF configures the initially attached L-HoA address for the MN.

After the authentication is passed, the L-NACF configures the MN to support the address configuration mode supported by the current access domain, such as IPv4, IPv6 stateless, or IPv6 stateful.

If the IPv4 configuration mode is adopted, the MN completes the address configuration through the DHCP v4 configuration process, and can insert the configuration option (Option) by the access physical device with the L2 DPCH Relay to carry the L2 Logic/Physical Access ID and other information.

If the IPv6 Statefull configuration mode is used, the MN obtains the address configuration from the DHCP v6 of the L-NACF by using the DHCP v6 protocol. The specific implementations of the foregoing two configurations are: The MN sends an address request to the L-NACF; and the L-NACF provides the address configuration provided by the MN.

If the IPv6 Stateless configuration mode is used, the MN can generate L-HoA according to the Home-Nextwork-Prefix of the AR and the Media Access Control (MAC) address of the MN.

Step s803: Select A-AR for the MN.

The A-AR in this step can be statically specified or dynamically specified for different MNs. For statically specified cases, a specified A-AR is fixed for different MNs. The MN can be fully authenticated or pre-connected. The address of the designated A-AR is obtained in the authentication process; if dynamically specified, the first attachment point AR of the MN in the access domain will be dynamically designated as the A-AR of the MN in the current access domain.

Step s804 _: Initial position binding is performed in the L-LMF and the H-LMF.

层次 Hierarchical location binding registration, location binding in L-LMF and H-LMF respectively; binding registration is initiated by the A-LMF proxy of the initial attachment point AR.

The A-LMF sends a location binding registration message (LBR/LBU) to the L-LMF. If it is the first registration, it sends an LBR message. If it is a subsequent registration, it sends an LBU message. The information carried in the LBR/LBU includes the following table. The L-LMF further sends an LBR/LBU message to the H-LMF, where the information carried includes the content shown in Table 3. The LBU message may further include a bound Lifetime value, when the value is reached. At the specified time, if the binding has not been updated, the corresponding binding entries in L-LMF and H-LMF will be deleted. Accordingly, the H-LMF and L-LMF loopback binding registration response messages (LBAs).

Step s805: The MN establishes an application layer service session by using a SIP message.

The implementation of this step is based on the system shown in FIG. 10: The MN carries the MN-Identifier and the L-HoA in a SIP Register message, registers with the SCF, and can complete the service layer session authentication of the MN; after that, the MN sends the SCF to the SCF. A SIP Invite message is sent to initiate a session. After receiving the SIP Invite message, the P-CSCF in the SCF initiates an address translation binding to the C-BGF through the RACF. The C-BGF acts as a media stream forwarding proxy. For the MN, the C-BGF represents the CN, and for the CN side, the C-BGF represents the MN; the media stream path that the C-BGF sends to the MN is: CN ~> C-BGF ~> A-AR ~> P-AR - ->匪.

The SIP session uses L-HoA as the session address. When the MN moves in the same access domain, the SIP session address does not change. The SCF can query the C-LMF and L-LMF to detect the change of the MN location.

The C-BGF is a media stream RTP/RTCP Proxy, which performs IP address conversion of the media stream;

The P-CSCF modifies the SDP address information of the SIP according to the address translation binding information provided by the C-BGF, so that the address location information of the MN is shielded from the CN, which satisfies the privacy requirement, and also avoids the L-HoA change of the MN. When the changed L-HoA needs to be notified to the CN.

Step s702: Discover and select the N-AR.

FIG. 11 is a flowchart of discovering and selecting an N-AR according to an embodiment of the present invention. As shown in Figure 11, it includes:

Step si 101: The MN performs L2 scanning, and sends L2 detection 4 Protext to the neighboring AR.

Step sll02: Each AR sends an L2 link Beacon message to the MN, which carries the physical identification information of the access point, such as the SSID and the BSID.

Step sll03: The MN reports the information about the current attachment point of the MN to the L-HMF by using the RtSolPr message through the A-ACF in the A-MMF of the current P-AR, and the RtSolPr message carries the peripheral connection acquired from the Beacon information. The physical ID of the entry point, such as SSID and BSID.

Step s 1104: The L-HMF queries the H-MMF or locally obtains the surrounding available AR of the current attachment point and its related information as an alternative AR.

Step sll05: The L-HMF makes a decision according to the information reported by the A-ACF of the current attachment point of the MN, the candidate AR information, and the configured policy, and selects the N-AR.

Step si 106: The L-HMF sends the information about the IP address and the MAC address of the N-AR to the MN through the A-ACF of the current attachment point of the MN by using the PrRtAdv message.

Since the AM-FE and the AR coexist in one device, the MN is equal to the PAA address of the N-AR, and the PAA of the P-AR also obtains the PAA address of the N-AR.

Step s703: Establish a pre-connection of the N-AR. FIG. 12 is a flowchart of establishing an N-AR pre-connection in an embodiment of a method according to the present invention. As shown in Figure 12, it includes:

Step S1201: Perform an attach pre-authentication process.

The pre-authentication in this step may be direct pre-authentication or indirect pre-authentication. FIG. 13 is a schematic diagram of direct pre-authentication in the embodiment of the present invention. As shown in FIG. 13, in the authentication mode, the MN directly passes the attachment of the N-AR. A pre-authentication request is initiated by the point. FIG. 14 is a schematic diagram of the indirect pre-authentication in the embodiment of the present invention. As shown in FIG. 14, in the authentication mode, the MN forwards the authentication request to the N-AR through the attachment point where the P-AR is located.

When the direct pre-authentication mode is adopted, the MN initiates an L2/L3 layer authentication request to the N-AR through the new access link; the N-AR PAA obtains the saved MSK key from the L-NACF, or passes the P - Secure channel established between AR to obtain MSK.

When the indirect pre-authentication mode is used, the MN initiates an L2/L3 authentication request through the access link of the current P-AR; the PAA in the P-AR forwards the L3 authentication request to the PAA of the N-AR according to the address of the N-AR. The N-AR's PAA obtains the saved MSK key from the L-NACF in a Context Transfer manner, or obtains the MSK through a secure channel established with the P-AR.

During the pre-authentication process, the N-AR also obtains configuration options from the L-NACF or P-AR, such as the IP address configuration mode of the access domain where the N-AR is located. If it is the IPv6 Stateless configuration mode, the N-AR The obtained is Home-Network-Prefix.

FIG. 15 is a flowchart of implementing pre-authentication in an embodiment of the present invention. As shown in FIG. 15, the method includes the following steps: Step sl501: The MN sends an L2/L3 pre-authentication request to the P-AR, where the identifier of the N-AR is carried.

Steps si 502 ~ si 503: The P-AR queries the L-NACF whether the MSK can be sent to the N-AR; the L-NACF sends a response message to the P-AR.

Steps sl504 ~ sl505: If the query result shows that the N-AR is a legal AR, the P-AR transmits the MSK to the PAA of the N-AR through a secure channel established with the N-AR, and the protocol used for the transmission may be 802.1. f; Send a pre-authentication success message to the MN at the same time.

Step si 506: A security association is established between the MN and the N-AR through the MSK.

Step S1202: Perform address pre-configuration. In this step, the pre-configured addresses include L-CoA and L-HoA. The L-CoA address is the address of the N-AR, and the N-AR is equivalent to the foreign agent in the MIPV4.

As for the L-HoA configuration, when the MN moves within an access domain, the L-HoA is unchanged; the L-HoA changes only when moving across the access domain. L-HoA address configuration is performed every time the attachment point is switched, whether it is in the access domain or between the access domains. When the MN moves within the access domain, the L-HoA configured before and after the handover The addresses are all the same. Specifically, in the IPv4 or IPv6 Statefull configuration mode, the DHCP server in the L-NACF configures the same address for each address request from the same MN or MAC address; if it is the IPv6 Stateless configuration mode, N-AR The Home-Network-Prefix sent to the MN is the same as the P-AR, and the MN generates the L-HoA in the same way.

Step sl203: Perform location binding update and resource reservation.

FIG. 16 is a flowchart of implementing location binding update and resource reservation in an embodiment of the present invention. As shown in FIG. 16, the A-LMF proxy MN in the N-AR initiates a location binding update request LBU to the L-LMF; or, the MN initiates a location binding update request LBU directly to the L-LMF via the A-LMF relay. When the L-LMF receives an LBU message, it first queries whether the binding entry with the same name already exists according to the MN-Identifier. If it exists, the L-LMF does not modify the binding entry first, but establishes a temporary binding entry. The existing binding entry corresponds to the attachment location of the P-AR, the temporary binding entry corresponds to the pre-attached location of the N-AR; the resource configuration parameter of the user or service in the transport layer User-Profile item in the temporary binding entry , will be selected or adjusted according to the access technology corresponding to the N-AR.

When the L-LMF establishes a temporary binding entry, the user-related information of the temporary binding entry is pushed to the RACF; the RACF reserves the resource for the temporary entry and locks it, and reports the result to the L-HMF. Specifically, the RACF performs one-way or two-way resource admission reservation and locks between A-AR -> N-AR -> MN according to the information pushed by the L-LMF; after the resource reservation is locked, to the L-NACF The L-HMF in the middle sends a resource admission reservation success message.

Subsequent to the completion of the mobile handover, the L-LMF receives the P-AR pair of the original binding entry. To bind the message, if the value of the Lifetime option of the LBU is set to 0, delete the original P-AR binding entry, and replace the original entry with the temporary binding entry to become the official location binding entry; when L-LMF binds the original When the entry is deleted, the RACF is notified to release the resource corresponding to the original binding.

If the RACF presents a hierarchical structure as shown in Figure 17, it is divided into access domains.

L-RACF and core domain H-RACF, then the L-LMF introduced above pushes the user information to the RACF to point to the L-RACF push user information located in the access domain.

Step S1204: Perform tunnel pre-establishment.

FIG. 18 is a flowchart of implementing pre-establishment of a tunnel in an embodiment of the present invention. The tunnel pre-establishment process in this embodiment is divided into two steps, namely, a tunnel establishment process of P-AR and N-AR, and a tunnel establishment process of A-AR and N-AR. As shown in Figure 18, it includes:

Steps sl801 ~ sl805: The L-HMF sends an instruction to the A-ADT in the P-AR and the A-ADT in the N-AR to establish a media stream transmission tunnel between the two; after the tunnel is established, the P-AR is simultaneously The media stream is forwarded to the MN and the N-AR.

Step si 806 ~ si 810: L-HMF to A-ADT and N-AR in A-AR respectively

The A-ADT issues an instruction to establish a media streaming tunnel between the two.

After the tunnel is established, the N-AR receives the media stream from both the P-AR tunnel and the A-AR tunnel, avoiding packet loss during tunnel switching.

Steps sl811 ~ sl815: After a preset period of time, the L-HMF deletes the P-AR and N-AR tunnels.

Step s704: Perform a handover to release the original attachment point resource.

Figure 19 is a flow diagram of performing a handover and releasing an original attachment point resource in an embodiment of the method of the present invention. As shown in Figure 19, it includes:

Steps sl901 ~ sl903: The MN modifies the default route to the address of the N-AR, and starts to send and receive media streams from the N-AR; according to the L2 link state indication, for example, Link going down, the link connection with the P-AR is cut off.

Step s 1904 ~ s 1907: The P-AR detects that the L2 link is disconnected, and sends a disconnection report to the L-HMF in the L-MMF. After the L-HMF is briefly timed, the A-AR and the P-AR are The tunnel between the two is deleted. The media stream path at this time is: C-BGF -> A-AR -> N-AR -> ΜΝ , and A-AR -> N-AR is an IP tunnel.

Steps sl908 ~ sl909: The A-LMF in the P-AR sends an LBU (De-registration) message to the L-LMF in the L-MMF; the L-LMF deletes the location binding entry of the original P-AR, and uses the N-AR The location binding entry is replaced.

Step s 1910 ~ s 1911: The L-LMF in the L-MMF sends a message to the L-RACF, instructing the RACF to release the relevant resources of the original P-AR; the RACF according to the indication of the L-LMF, to the MN at the N-AR attachment point The resource performs reservation execution and delivery control policies, and releases related resources of the original P-AR attachment point.

It should be noted that the session establishment process used in the foregoing embodiment is based on SIP.

In the case of the IP Multimedia Subsystem (IMS) architecture, for the case of non-IMS and non-SIP sessions, only the specific session establishment process is different, and the other steps are the same as the above embodiments.

Based on the foregoing method, FIG. 20 is a schematic structural diagram of a system embodiment of the present invention. As shown in FIG. 20, the system includes: an MN21 and an NGN network 22; wherein the NGN network 22 further includes a core network domain 221 and an access network domain. 222 transport layer control management system;

The MN21 is configured to access the NGN network 22, and perform mobility switching in the access domain 222 in the NGN network 22; a transport layer control management system, configured to connect the MN21 to the NGN network 22, complete the initial attach process, and When the MN 21 needs to perform the mobile handover in the access domain 222, the N-AR is discovered and selected in the current access domain 222, the connection pre-establishment is performed on the selected N-AR, and the initial attachment information is modified, and Perform a switch to release the original attachment point resource.

The transport layer control management system located in the core network domain 221 further includes a home network attach control function entity H-NACF 2211 and a home resource admission control function entity H-RACF 2212. The transport layer control management system located in the access domain 222 further includes a local Network Attachment Control Function Entity L-NACF 2221, Local Resource Admission Control Function Entity L-RACF 2222;

H-NACF2211, configured to perform full authentication of the MN21 when the MN21 initially accesses the NGN network, and deliver the generated SA and user configuration information to the L-NACF 2221; And querying, according to the physical identification information of the neighboring access point of the current attachment point obtained from the L-NACF 2221, candidate AR information applicable to the mobile handover around the current attachment point;

The L-NACF 2221 is configured to implement management control on the mobile switching of the MN 21 in the access domain 222, and query the information of the candidate AR information in the H-NACF 2211 and the neighboring access point L2 reported by the MN 21 according to the configured information. Select a policy, select N-AR; perform fast pre-authentication based on the SA and user configuration information received from H-NACF2211, configure L-HoA address for MN21, perform location binding update, and during tunnel pre-establishment and execution handover Instructing the AM-FE 2224 to establish or tear down a media stream tunnel;

The L-RACF2222 is configured to receive related user information that is sent after the location binding update is performed by the L-NACF2221, perform resource reservation and locking on the user information, and release the original attachment point resource according to the indication of the L-NACF2221 during the handover process. .

H-RACF2212, used to receive the address binding request sent by the SCF2214, forwarded to the C-BGF2213; the H-RACF2212 can also be used to forward the resource request from the SCF2214 to the L-RACF2222.

The H-NACF2211 saves and binds the address of the access domain where the MN21 is currently located, where

The current access domain address of the MN21 includes the L-NACF2221 location index information; the L-NACF2221 stores and binds the current location information of the MN21 in the access domain;

The NGN network 22 further includes a service layer control management system, and the service layer control management system further includes an SCF 2214 located in the core network domain, configured to query the H-NACF 2211 for location information of the MN 21, and receive the query result returned by the H-NACF 2211; The H-NACF 2211 queries the corresponding L-NACF for the current location information of the access domain where the MN 21 is located according to the saved L-NACF2221 location index information, and sends the query result to the SCF 2214. The SCF 2214 is further configured to: request resources from the H-RACF 2212 in the initial attach process, and initiate address translation binding to the C-BGF 2213 through the H-RACF 2212, so as to implement the conversion of the MN 21 in the access domain 222 address and the core domain 221 address. .

The transport layer of the NGN network 22 access network domain 222 further includes an A-AR 2223 for forwarding the anchor point of the media stream in the current access domain of the MN 21; the A-AR 2223 is a pre-designated fixed AR, or the MN 21 is accessing When the domain is first attached The attachment point AR. The transport layer of the core network domain 221 of the NGN network 22 further includes a C-BGF 2213, which is an L3 input/output point between the core domain and the access domain of the MN21 media data stream. In addition, the access network 222 further includes an AM-FE 2224, and its specific components and functions of the components are as shown in FIG. 5, and details are not described herein again.

FIG. 21 is a schematic structural diagram of a structure of an L-NACF according to an embodiment of the present invention. As shown in FIG. 21, the L-NACF 2221 includes a local mobility management function entity L-MMF2101, an AAA server, and a network address configuration function of the access domain. Entity NAC-FE2103; wherein L-MMF2101 further comprises: a local handover management function entity L-HMF21011 of the access domain and a local location management function entity L-LMF21012 of the access domain;

The L-HMF 21011 is configured to query the candidate AR information in the H-NACF 2211 and the neighboring access point L2 detection information reported by the MN 21, select an N-AR according to the configured selection policy, and select the selected N-AR address. The information is sent to the MN 21; and the AM-FE 2224 is instructed to establish or remove the media stream tunnel during the tunnel pre-establishment and execution handover; L-LMF 21012 is used to perform location binding update under the indication of the AM-FE 2224; AAA Server 2102, It is used to perform fast pre-authentication based on the SA and user configuration information received from the H-NACF2211. The NAC-FE2103 can be used as a DHCP server to configure the L-HoA address and access network configuration parameters for the MN21.

FIG. 22 is a schematic structural diagram of a structure of an H-NACF according to an embodiment of the present invention. As shown in FIG. 22, the H-NACF 2211 specifically includes a mobility management function entity H-MMF2201 and an AAA server Serve2202 of the core domain; the H-MMF 2201 further includes: a mobile switching management entity H-HMF22011 and a core of the core domain. The home location management function entity of the domain H-LMF22012;

AAA Server2202, configured to perform full authentication on the MN21 when the MN21 initially accesses the network, and send the generated SA and user configuration information to the L-NACF2221; H-HMF22011, according to the current obtained from the L-NACF2221 The identification information of the attachment point P-AR is used to query candidate AR information that can be used for mobile handover around the current attachment point. H-LMF22012 is used to save and bind the attachment information provided by the L-NACF2221.

20, 21 and 22 are only examples of the present invention. In practical applications, FIG. Other application entities may also be included in 21 and 22. For details, please refer to FIG. 4, and details are not described herein again.

It should be noted that the solution in the embodiment of the present invention is not only applicable to the network architecture described in the embodiment of the present invention, but also applicable to other network architectures having similar structures, but only within a range that can be predicted by those skilled in the art. The specific implementation details may differ slightly.

It can be seen that, in the technical solution of the embodiment of the present invention, the advantages of fast, packet loss, layering, and small changes to the MN in the existing FMIP, HMIP, SMIP, and PMIP protocols are applied to the extended NGN architecture, and NGN. The hierarchical architecture is organically integrated, thereby achieving seamless switching within the access domain, that is, the Intra-AN mode in the NGN architecture.

In conclusion, the above is only a preferred embodiment of the present invention and is not intended to limit the scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims

Rights request

A method for implementing mobile handover, characterized in that, when an initial attached mobile node MN has been completed in an access network domain, it is required to switch from the current access router P-AR to the target access within the access network domain. When the router is N-AR, the method includes:

Select the target access router N-AR in the access domain;

After the connection pre-establishment is completed, the handover is performed, and the resources of the current access router P-AR are released.

2. The method according to claim 1, wherein the initial attachment specifically comprises:

The MN performs full authentication of the initial attachment, and establishes a security association SA;

Configuring a local home address L-HoA in the initially attached access domain for the MN; selecting a local anchor router A-AR for the MN;

The initial location binding is performed in the local location management function entity L-LMF of the access domain and the home location management function entity H-LMF of the core domain.

The method of claim 2, wherein the selecting the N-AR comprises:

The MN sends an L2 detection message to the neighboring access router AR, receives the response message sent by the neighboring AR, and carries the neighboring AR physical identification information in the response message in the P-AR related information. , the local switching management function entity L-HMF to the access domain;

The L-HMF queries from the mobility management function entity H-MMF of the core domain or obtains the neighboring AR of the P-AR locally as an alternative AR;

The L-HMF selects one of the candidate ARs as the N-AR according to the P-AR related information, the candidate AR information, and the pre-configured policy reported by the MN; the L-HMF will include A message having the N-AR related information is sent to the UI.

4. The method of claim 3, wherein said pair of selected N-ARs The connection pre-establishment is performed, and the initial attachment information is modified during the connection pre-establishment process, which specifically includes:

Attachment pre-authentication, address pre-configuration, location binding update and resource reservation, and tunnel pre-establishment are performed on the N-AR.

The method according to claim 4, wherein the attach pre-authentication is a direct attach pre-authentication or an indirect attach pre-authentication; wherein the direct attach pre-authentication is that the MN directly passes the N-AR The attaching point is located to initiate an authentication request; the indirect attach pre-authentication is that the MN forwards the authentication request to the N-AR through an attachment point where the current access router P-AR is located.

The method according to claim 5, wherein the pre-configured address in the address pre-configuration includes a local home address L-HoA in the access domain and a local care-of address L-CoA in the access domain; The L-CoA is an address of the N-AR.

The method of claim 6, wherein the location binding update and the resource reservation comprise:

The N-AR corresponding access point location management function entity A-LMF, the MN is initiating a location binding update request to the local location management function entity L-LMF of the access domain; or, the MN The A-LMF relay directly initiates a location binding update request to the L-LMF;

The L-LMF queries whether a binding entry with the same name already exists, and if so, the L-LMF establishes a temporary binding entry, where the temporary binding entry corresponds to the pre-attached location of the N-AR;

The L-LMF pushes the user information of the temporary binding entry to the RACF; the RACF performs resource reservation and lock according to the pushed information.

The method of claim 7, wherein the pre-establishing the tunnel comprises:

The L-HMF sends an instruction to the P-AR and the N-AR, respectively, to establish a media stream transmission tunnel between the P-AR and the N-AR;

The L-HMF sends an instruction to the A-AR and the N-AR, respectively, to establish a media stream transmission tunnel between the A-AR and the N-AR; The N-AR simultaneously receives a media stream from a tunnel between the P-AR and a tunnel with the A-AR.

The method according to claim 8, wherein the performing the switching to release the original attachment point resource comprises:

The MN modifies the default route to the address of the N-AR, and disconnects the Layer 2 L2 link with the P-AR from the N-AR transceiver media stream;

The P-AR detects that the L2 link is disconnected, and sends a disconnection report to the L-HMF, where the L-HMF deletes the tunnel between the A-AR and the P-AR;

The P-AR notifies the L-LMF to delete the location binding entry of the original P-AR, and replaces the location binding entry of the N-AR;

And the RACF performs a reservation execution and a delivery control policy on the resource of the MN at the N-AR attachment point according to the indication of the L-LMF, and releases the related resource of the MN at the original P-AR attachment point.

A system for implementing mobile handover, the system comprising: a mobile node MN and a next generation network NGN; the NGN network includes a transport layer control management system located in a core network domain and an access network domain;

The system according to claim 10, wherein the transport layer control management system located in the core domain includes a home network attach control function entity H-NACF; and the transport layer control management located in the access domain The system includes a local network attach control function entity L-NACF and a local resource admission control function entity L-RACF;

The H-NACF, configured to perform the full authentication on the MN when the MN accesses the access domain, and send the generated SA and user configuration information to the L-NACF; According to the current attachment point peripheral access point obtained from the L-NACF Physical identification information, querying candidates for the mobile handover around the current attachment point

The L-NACF is configured to query the candidate AR information in the H-NACF and the L2 detection information of the neighboring access point reported by the MN, and select the N- according to the configured selection policy. The AR performs fast pre-authentication according to the SA and the user configuration information received from the H-NACF, configures the local home address L-HoA in the access domain for the MN, performs location binding update, and pre-establishes the tunnel in the tunnel. The instruction access management function entity AM-FE establishes a media stream tunnel during the handover process;

The L-RACF is configured to receive related user information that is sent after the location binding update is performed by the L-NACF 2221, perform resource reservation and locking on the user information, and according to the L-NACF in the handover process. Indicates to release the resources of the current access router P-AR.

The system of claim 11, wherein the H-NACF is further configured to save and bind an access network address where the MN is currently located, where the MN is currently located in the access network. The domain address includes the L-NACF location index information; the L-NACF is further configured to save and bind current location information of the MN in the access domain; the NGN network further includes a service layer control management system, The service layer control management system includes a service control layer SCF, where the SCF is located in a core network domain, and is configured to query the H-NACF for location information of the MN, and receive a query result returned by the H-NACF;

The H-NACF according to the saved L-NACF location index information, corresponding to

The L-NACF queries the current location information of the access domain where the MN is located, and reports the query result to the SCF.

The system according to claim 12, wherein the transport layer control management system located in the core domain further includes a home resource admission control function entity H-RACF; the NGN network further includes a core network domain and Accessing the transport layer of the network domain, the transport layer located in the core network domain further includes a core network border gateway C-BGF; the SCF is further configured to request resources from the H-RACF during the initial attach process, and pass the The H-RACF initiates address translation binding to the C-BGF, and implements conversion of the MN in the access domain address and the core domain address.

The system according to claim 13, wherein the transport layer located in the access domain further comprises a local anchor router A-AR, and the A-AR is the MN in the current access domain Media stream forwarding anchor point;

The A-AR is a pre-designated AR, or an AR of an attachment point where the MN is attached for the first time in the access domain.

A local network attachment control function entity L-NACF, wherein the L-NACF includes a local mobility management function entity L-MMF of the access domain; the L-MMF further includes: The local handover management function entity L-HMF of the domain and the local location management function entity L-LMF of the access domain;

The L-LMF is configured to perform location binding update under the indication of the AM-FE.

The L-NACF according to claim 15, wherein the L-NACF further includes an AAA server Server and a network address configuration function entity NAC-FE;

The AAA server is configured to perform fast pre-authentication according to the SA and the user configuration information received from the H-NACF;

The NAC-FE is configured to configure, for the MN, a local home address in an access domain.

L-HoA address and access network configuration parameters.

A home network attachment control function entity H-NACF, wherein the H-NACF includes a mobility management function entity H-MMF of the core network domain; the H-MMF further includes: a core network domain a mobile handover management entity H-HMF and a home location management function entity H-LMF of the core domain;

The H-LMF is configured to save and bind the attachment information provided by the L-NACF.

The H-NACF according to claim 17, wherein the H-NACF further includes an AAA server Server;

The AAA server is configured to perform complete authentication on the MN when the MN initially accesses the network, and send the generated SA and user configuration information to the local network attach control function entity L-NACF.

An access management function entity AM-FE, wherein the AM-FE further includes an access mobility management function entity A-MMF; the A-MMF specifically includes an access attachment point location management function. Entity A-LMF, access point control function entity A-ACF, and access point media stream data forwarding function entity A-DTF;