KR20100061000A - Method for performing handover in heterogenous wireless networks based media independent handover - Google Patents

Abstract

PURPOSE: An inter-heterogeneous handover performance method MIH-based is provided to provide IP portability of a terminal PMIP(Proxy Mobile IP)-based without interlocking between AAA(Authentication, Authorization and Accounting) server and a service provider in an inter-heterogeneous wireless network vertical handover. CONSTITUTION: An MME(Mobility Management Entity) unit(110) grasps neighbor network information of a mobile terminal(100). The MME(Mobility Management Entity) unit determines a handover target network based on service quality decision result. A terminal ID management unit(120) manages IP address of the mobile terminal. A MIH(Media Independent Handover) control unit(130) acquires information elements through the MIH message between the mobile terminal and network. An IP management device driver(140) watches IP set up procedure of the mobile terminal according to IP allocation protocol information.

Description

Method for Performing Handover in Heterogenous Wireless Networks Based Media Independent Handover}

The present invention relates to a method for performing handover, and more particularly, to a method for performing handover between heterogeneous networks based on a media independent handover (hereinafter, referred to as 'MIH').

Mobile IP, mobile IPv6, or mobility protocols based on them must support the mobile IP stack at terminals and routers.

PMIPv6 and PMIPv4 are protocols under standardization in IETF to provide network-based IP mobility in IPv4 and IPv6 networks, respectively, and require the implementation of protocols to support IP mobility only in the network, and separate management for IP mobility management at terminals. Does not require implementation of the protocol.

Proxy Mobile IP (hereinafter referred to as 'PMIP') is a protocol for supporting IP mobility to a user by introducing a mobility protocol stack into a network infrastructure without changing a terminal's IP stack.

In other words, PMIP does not require the implementation of a protocol stack for providing IP mobility to mobile terminals. The mobile terminal has two network interface cards (hereinafter referred to as 'NIC') for vertical handover.

Therefore, when implementing PMIP, the mobile station should be able to allocate the same IP to different NICs for PMIP-based mobility support between heterogeneous networks.

However, the conventional Microsoft Windows-based operating system has a problem that it is impossible to assign the same IP to different NICs and cannot provide PMIP-based IP mobility between heterogeneous networks without modifying terminals.

In order to solve such a problem, the present invention is to provide a method for performing handover between heterogeneous networks of a mobile terminal based on MIH when applying PMIP.

According to an aspect of the present invention, a method for performing handover according to an aspect of the present invention includes (a) an information message for obtaining peripheral network information, wherein the peripheral network information includes IP mobility protocol type information and IP allocation protocol information. Exchanging with an information server to obtain the neighbor network information; (b) transmitting a query message for inquiring whether the UE can guarantee the quality of service during handover to neighboring networks through the currently connected first proxy mobile agent, and grasping the service quality determination result from the neighboring networks. step; (c) determining a handover target network among the neighboring networks according to the service quality determination result, and using the first proxy mobile agent currently connected to the command message indicating a handover schedule, determining the handover target network; Sending to the 2 proxy mobile agent; (d) If a handover is allowed from the second proxy mobile agent, perform a link connection, and then generate a first IP allocation packet for allocating an IP according to the IP allocation protocol information, and transmit it to the second proxy mobile agent. Making; (e) if it detects transmission of the first IP assignment packet, detecting that a new network interface card is to be allocated an IP and deleting the IP assigned to the existing network interface card; And (f) allocating IP to the new network interface card when receiving a second IP allocation packet indicating the IP allocation from the second proxy mobile agent.

According to an aspect of the present invention, a method for performing handover includes (a) exchanging an information message with an information server to obtain peripheral network information, wherein the peripheral network information includes IP mobility protocol type information and IP allocation protocol information. Obtaining neighbor network information; (b) transmitting a query message for inquiring whether the UE can guarantee the quality of service during handover to neighboring networks through the currently connected first proxy mobile agent, and grasping the service quality determination result from the neighboring networks. step; (c) determining a handover target network among the neighboring networks according to the service quality determination result, and using the first proxy mobile agent currently connected to the command message indicating a handover schedule, determining the handover target network; Sending to the 2 proxy mobile agent; (d) If a handover is allowed from the second proxy mobile agent, perform a link connection, and then generate a first IP allocation packet for allocating an IP according to the IP allocation protocol information to the second proxy mobile agent. Transmitting; And (e) detecting the reception of the second IP allocation packet indicating the IP allocation from the second proxy mobile agent and deleting the IP allocated to the existing network interface card for a predetermined time, and then deleting the second IP allocation packet. Receiving and assigning an IP to the new network interface card.

According to an aspect of the present invention, a method for performing handover includes (a) a mobile station-free handover to obtain peripheral network information, wherein the peripheral network information includes IP mobility protocol type information and IP allocation protocol information. Exchanging a Media Independent Handover message with an information server to identify the neighbor network information; (b) transmitting a second intermediary irrelevant handover message to neighbor networks to ensure a quality of service based on the neighbor network information; (c) The proxy mobile agent of the handover target network is determined through a third medium irrelevant handover message, which determines a handover target network based on the service quality guarantee among the neighboring networks and indicates that the handover target network has been determined. Transmitting to; And (d) if handover is allowed from the proxy mobile agent, performing IP management by monitoring an IP setting process of the mobile terminal according to the IP allocation protocol information.

By the above configuration, the present invention provides the IP mobility of the PMIP-based terminal without interworking between the AAA server, operators in the vertical handover between heterogeneous wireless networks.

The present invention supports seamless IP mobility for real-time multimedia service applications without modification of a protocol or application service for separate network mobility.

The present invention provides compatibility by following the same procedure as the existing PMIP in an environment that does not support MIH-PMIP interworking.

The present invention can be expected to provide a mobile terminal having a Windows-based operating system to provide a PMIP-based IP mobility technology.

The present invention can be expected to be able to quickly and easily introduce a method of performing a handover.

The present invention can be expected to use the reserved field of the MIH information element to ensure the effect of ensuring compatibility with the network implemented MIH.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

Throughout the specification, when a part is said to "include" a certain component, it means that it can further include other components, without excluding other components unless specifically stated otherwise. In addition, the terms “… unit”, “… unit”, “module”, “block”, etc. described in the specification mean a unit that processes at least one function or operation, which is hardware or software or a combination of hardware and software. It can be implemented as.

1 is a broadband code division multiple access (Wideband Code Division Access) in a Wibro network in a network in which PMIP and MIH are applied to a 3G / Wireless Broadband Internet (Wibro) network to which the present invention is applied. Hereinafter, a structure diagram showing an example in which handover is performed through a WCDMA network).

For convenience, the proxy mobile agent (hereinafter referred to as PMA) of the network to which the mobile terminal 100 is connected is called a PMA (old PMA) 200 to which the terminal is currently connected, and is connected by handover. The PMA of the network is called a new PMA 300 or a PMA 300 of the target network.

The home agent (hereinafter referred to as 'HA') 400 receives a packet received from a partner node 600 through a tunnel between the HA 400 and the PMA to establish a PMA 200. , 300). Subsequently, the PMAs 200 and 300 transmit the packet to the mobile terminal 100 through the wireless network.

On the contrary, the packet transmitted from the mobile terminal 100 is transmitted to the HA 400 through the tunnel through the PMAs 200 and 300, and is transmitted from the HA 400 to the CN 600.

The PMA / HAs 200, 300, and 400 at both ends of the tunnel remove the outer header of the tunneled packet and transmit the packet to the external Internet network or the mobile terminal 100.

When the mobile terminal 100 moves from the Wibro network to the WCDMA network, the new PMA 300 detects the new mobile terminal 100 and generates a PRRQ (Proxy Registration Request) message and transmits it to the HA 400. The HA 400 performs user authentication through an authentication server (AAA), creates a tunnel between the HA / PMAs (200, 300, and 400), and generates a PRRP (Proxy Registration Reply) message in response to the PRRQ message. Send to the new PMA (300).

2 is a block diagram schematically showing the internal configuration of the packet monitoring-based mobile terminal 100 according to an embodiment of the present invention, Figure 3 is a packet delay-based mobile terminal 100 according to an embodiment of the present invention It is a block block diagram which shows the structure briefly.

Packet monitoring-based mobile terminal 100 according to an embodiment of the present invention includes a mobility management unit 110, a terminal ID management unit 120, MIH control unit 130 and IP management device driver 140.

Packet delay based mobile terminal 100 according to an embodiment of the present invention is a mobility management unit 110, a terminal ID management unit 120, a modified Dynamic Host Configuration Protocol (hereinafter referred to as 'DHCP') stack ( 150) and a modified Point-to-Point Protocol (PPP) stack 160.

The mobility manager 110 exchanges the first MIH message with the information server 500 to obtain the neighbor network information in the mobile terminal 100 to identify the neighbor network information. Here, the neighbor network information includes the extended information element for the present invention, that is, the IP mobility protocol type information of the target network and the IP allocation protocol information together with the neighbor network information including the radio access technology of the neighbor network.

The mobility manager 110 transmits a second MIH message to neighbor networks to ensure service quality based on the neighbor network information, and receives a service quality determination result from the neighbor networks.

The mobility manager 110 determines the handover target network based on the service quality determination result and transmits the information indicating that the handover target network has been determined to the PMA of the handover target network through the third MIH message.

The terminal ID manager 120 manages an IP address such as an International Mobile Subscriber Identity (MAC), a MAC address, etc. of the mobile terminal 100.

The MIH controller 130 supports a general MIH protocol, delivers link layer information such as handover warning or completion of handover to a higher layer, and obtains various information elements through a MIH message between the terminal 100 and the network. .

The IP management device driver 140 monitors the IP setting process of the mobile terminal 100 according to the IP allocation protocol information and notifies the mobility management unit 110 that the handover is imminent.

The modified DHCP stack 150 and the modified PPP stack 160 delay the packet for confirming the final IP configuration for a predetermined time according to the IP allocation protocol information, and notify the mobility management unit 110 that the handover is imminent.

4A and 4B are diagrams for explaining signal flow when the mobile terminal 100 performs vertical handover from a WCDMA network to a Wibro network according to an embodiment of the present invention.

The link / physics layer of the mobile terminal 100 detects a handover based on the currently connected link quality, generates a link going down event through the MIH control unit 130, and transmits it to the mobility management unit 110. (S100).

The mobility management unit 110 obtains the neighbor network information through the transmission of the MIH_Get_Information Request message and the MIH_Get_Information Response message with the information server 500 (S102). Here, the MIH_Get_Information Response message includes the neighbor network information.

Subsequently, the mobility manager 110 generates a MIH_MN_HO_Candidate_Query Request message to the currently connected PMA (old PMA) 200 to inquire whether neighboring networks can guarantee quality of service (QoS) when the UE hands over. It transmits (S104). Here, the MIH_MN_HO_Candidate_Query Request message includes the terminal ID to be used in the target network. The target network refers to a neighbor network to which the mobile terminal 100 moves by handover.

Subsequently, the currently connected PMA 200 transmits the terminal ID to be used in the target network to the PMA 300 of neighbor networks through the MIN_N2N_Query_Resources Request (S106).

The PMAs 300 of neighboring networks determine whether QoS can be guaranteed for the mobile terminal 100, and include the QoS determination result in the MIN_N2N_Query_Resources Response to transmit to the currently connected PMA (old PMA) 200 ( S108).

The currently connected PMA 200 transmits the QoS determination result and the terminal ID to be used in the target network to the mobility management unit 110 through the MIH_MN_HO_Candidate_Query Response message (S110).

The mobility management unit 110 determines a handover target network among neighbor networks capable of guaranteeing QoS through a policy-based handover algorithm (S112). In the embodiment of the present invention, it is assumed that the Wibro network is selected.

The mobility manager 110 generates a MIH_MN_HO_Commit Request and transmits it to the currently connected PMA 200 (S114).

The currently connected PMA 200 generates a MIH_N2N_HO_Commit Request and transmits it to the PMA 300 of the target network (S116). The PMA 300 of the target network receives a terminal ID according to a wireless access network technology that the terminal is going to handover through the MIH_MN_HO_Commit Request and the MIH_N2N_HO_Commit Request and can determine the terminal in the target network with the current IP address of the mobile terminal 100. . Here, the PMA 300 of the target network means the PMA of the network determined as the handover target network among the PMAs of the neighboring network.

The mobility manager 110 drives a Wibro network interface card (hereinafter referred to as 'NIC') through MIH_Link_Action.Request when handover is allowed from the PMA 300 of the target network through the MIH_MN_HO_Commit Response and MIH_N2N_HO_Commit Response. To perform a link access process (S118, S120, S122).

When the connection process of the link layer is completed, the mobile terminal 100 generates an NDIS_STATUS_MEDIA_CONNET Indication of a network driver interface specification (hereinafter referred to as NDIS) (S124).

The operating system operates the IP address assignment protocol by the IP address assignment method set for each NIC.

As shown in FIG. 4, when DHCP is used, the DHCP client 170 generates and broadcasts a DHCP discover message (S126).

The PMA 300 of the target network receiving the DHCP discover message creates a tunnel through the transmission and reception of the PRRQ / PRRP message with the home agent 400 (S128), and generates a DHCP offer message to transmit the DHCP client 170 to the DHCP client 170. The mobile terminal 100 informs the mobile terminal 100 of the IP address already used in the network before the handover (S130).

The mobile terminal 100 confirms that the IP will be used as the PMA 300 of the target network again through a DHCP request because DHCP is a protocol made on the assumption that there are a plurality of DHCP servers in the broadcast access network. Thereafter, the PMA 300 of the target network finally allocates an IP address to the terminal through the DHCP Ack.

In the embodiment of the present invention, an IP address allocation method is exemplified by DHCP for convenience of description, but various IP address allocation methods such as an Internet Protocol Control Protocol (hereinafter referred to as 'IPCP') of a 3G network may be used. You can choose.

In the case of vertical handover in the PMIP-based heterogeneous wireless network environment, the IP address management method of the mobile terminal 100 is divided into A and B methods.

A method is a method in which a UE monitors a packet involved in an IP allocation procedure such as DHCP discover / offer / request / ack and IPCP configure-request / configure-Ack.

The mobile terminal 100 knows that the IP mobility protocol of the handover target network is PMIP through the MIH (that is, the MIH_Get_Information Response message) and that the IP allocation protocol of the network is DHCP.

If the DHCP client 170 receives the DHCP offer message after step S130, that is, the DHCP client 170 generates a DHCP request to allocate an IP to the new NIC 190 and transmits the generated DHCP request to the DHCP server of the target network (S132a).

At this time, when detecting the transmission of a specific IP allocation packet such as a DHCP request, the IP management device driver 140 transmits information indicating that handover is imminent to the mobility management unit 110 (S134a and S136a). Subsequently, the mobility manager 110 deletes the IP address assigned to the old NIC 180 (S138a).

When the DHCP client 170 receives the DHCP ack from the DHCP server 300 of the target network, the DHCP client 170 allocates an IP to the new NIC 190 according to the IP allocation protocol (S140a and S142a).

Method B is a method of delaying a predetermined time without transmitting the packet to the terminal operating system when receiving a packet that finally allocates IP such as DHCP ack and IPCP Configure-Ack, and notifying the mobility management unit 110 that the handover is imminent. .

 When the DHCP client 170 receives the DHCP offer message, the DHCP client 170 generates a DHCP request and transmits the generated DHCP request to the DHCP server 300 of the target network (S132b).

The modified DHCP stack 150 delays the DHCP ack for a predetermined time and transmits the information indicating that the handover is imminent to the mobility management unit 110 (S134b and S136b). Subsequently, the mobility manager 110 deletes the IP address assigned to the old NIC 180 (S138b).

The modified DHCP stack 150 successfully deletes the IP of the old NIC 180, and then transmits a DHCP ack to the DHCP client 170 (S140b).

Subsequently, when the DHCP client 170 receives the DHCP ack from the DHCP server 300 of the target network, the DHCP client 170 allocates an IP to the new NIC 190 according to the IP allocation protocol (S142b).

The method B used the modified DHCP stack 150 as a method of delaying the packet, but may delay the packet through the IP management device driver 140.

The aforementioned old NIC 180 may be represented by NIC1 180 and new NIC 190 may be represented by NIC2 190.

5 is a diagram for explaining an extended information element of MIH according to an embodiment of the present invention.

The field proposed in the present invention is added to the information element of the data format for the IP configuration of the MIH standard.

Specifically, the extended information element is applied to information elements having the names IE_NET_MOB_MGMT_PROT, IE_NET_IP_CFG_METHODS in “Access Network Specific Information Elements” of the information elements of the MIH.

First, the PMIP part is indicated using one bit of reserved bits 7 to 15 of the IP_MOB_MGMT field 700 indicating the IP mobility support protocol to indicate that the MIH of the UE supports the PMIP.

In addition, the reserved bit 4 of the IP_CFG_MTHDS 710 specifies that the IP allocation method of the handover target network is IPCP.

The aforementioned extended information element is included in the MIH_Get_Information Response message to inform the mobile station 100 of the IP mobility protocol type information and IP allocation protocol information of the neighbor network.

6 is a diagram illustrating an extended MIH_Candidate_Query related service primitive and a MIH message format according to an embodiment of the present invention, and FIGS. 7A and 7B are a diagram illustrating a MIH_HO_Commit related service primitive and a MIH message format according to an embodiment of the present invention. .

Service primitives such as MIH Candidate Query have been extended to include terminal ID lists 720 and 730 for delivery of terminal IDs available in the target network for admission control in the target network.

In addition, the MIH HO Commit related service primitive has been extended to include the terminal ID (740, 750, 760) available in the handover target network.

The embodiments of the present invention described above are not implemented only by the apparatus and / or method, but may be implemented through a program for realizing functions corresponding to the configuration of the embodiment of the present invention, a recording medium on which the program is recorded And such an embodiment can be easily implemented by those skilled in the art from the description of the embodiments described above.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

FIG. 1 is a structural diagram illustrating an example in which a UE performs a handover from a Wibro network to a WCDMA network in a network in which PMIP and MIH are applied to a 3G / Wibro network to which the present invention is applied.

2 is a block diagram schematically illustrating an internal configuration of a packet monitoring-based mobile terminal according to an embodiment of the present invention.

3 is a block diagram schematically illustrating an internal configuration of a packet delay based mobile terminal according to an embodiment of the present invention.

4A and 4B are diagrams for explaining signal flow when a mobile terminal performs vertical handover from a WCDMA network to a Wibro network according to an embodiment of the present invention.

5 is a diagram for explaining an extended information element of MIH according to an embodiment of the present invention.

6 is a diagram illustrating an extended MIH_Candidate_Query related service primitive and MIH message format according to an embodiment of the present invention.

7A and 7B illustrate MIH_HO_Commit related service primitives and MIH message formats according to an embodiment of the present invention.

Claims (10)

(a) exchanging an information message with an information server to obtain peripheral network information, wherein the peripheral network information includes IP mobility protocol type information and IP allocation protocol information; (b) transmitting a query message for inquiring whether the UE can guarantee the quality of service during handover to neighboring networks through the currently connected first proxy mobile agent, and grasping the service quality determination result from the neighboring networks. step; (c) determining a handover target network among the neighboring networks according to the service quality determination result, and using the first proxy mobile agent currently connected to the command message indicating a handover schedule, determining the handover target network; Sending to the 2 proxy mobile agent; (d) If a handover is allowed from the second proxy mobile agent, perform a link connection, and then generate a first IP allocation packet for allocating an IP according to the IP allocation protocol information, and transmit it to the second proxy mobile agent. Making; (e) when detecting transmission of the first IP allocation packet, detecting that a new network interface card is to be allocated an IP and deleting the IP assigned to the existing network interface card; And (f) assigning an IP to the new network interface card when receiving a second IP allocation packet indicating the IP allocation from the second proxy mobile agent; How to perform a handover comprising a. According to claim 1, The query message or the command message includes a terminal ID that can be used in the handover target network. (a) exchanging an information message with an information server to obtain peripheral network information, wherein the peripheral network information includes IP mobility protocol type information and IP allocation protocol information; (b) transmitting a query message for inquiring whether the UE can guarantee the quality of service during handover to neighboring networks through the currently connected first proxy mobile agent, and grasping the service quality determination result from the neighboring networks. step; (c) determining a handover target network among the neighboring networks according to the service quality determination result, and using the first proxy mobile agent currently connected to the command message indicating a handover schedule, determining the handover target network; Sending to the 2 proxy mobile agent; (d) If a handover is allowed from the second proxy mobile agent, perform a link connection, and then generate a first IP allocation packet for allocating an IP according to the IP allocation protocol information, and transmit it to the second proxy mobile agent. Making; And (e) Detecting the reception of the second IP allocation packet indicating the IP allocation from the second proxy mobile agent and deleting the IP assigned to the existing network interface card for a predetermined time delay, and then deleting the second IP allocation packet. Receiving and assigning an IP to the new network interface card How to perform a handover comprising a. The method of claim 3, The query message or the command message includes a terminal ID that can be used in the handover target network. A method for performing handover in a network providing IP mobility, (a) exchanging a first media independent handover message with an information server to obtain peripheral network information in the mobile terminal, wherein the peripheral network information includes IP mobility protocol type information and IP allocation protocol information. Identifying the surrounding network information; (b) transmitting a second intermediary irrelevant handover message to neighbor networks to ensure a quality of service based on the neighbor network information; (c) The proxy mobile agent of the handover target network is determined through a third medium irrelevant handover message, which determines a handover target network based on the service quality guarantee among the neighboring networks and indicates that the handover target network has been determined. Transmitting to; And (d) if handover is allowed from the proxy mobile agent, performing IP management by monitoring an IP setting process of the mobile terminal according to the IP allocation protocol information; How to perform a handover comprising a. 6. The method of claim 5, In step (d), (e) delaying the packet confirming the final IP setting according to the IP allocation protocol information, deleting the set IP of the network where the mobile terminal is located, and processing the IP setting of the handover target network; The handover performing method further comprising. 6. The method of claim 5, In step (b), Mapping a terminal ID using a neighbor network access technology obtained from the neighbor network information; Transmitting the terminal ID to a first proxy mobile agent currently connected through the second medium unrelated handover message; Transmitting, by the first proxy mobile agent, the terminal ID to the neighbor networks; Performing handover admission control based on the terminal ID in the neighboring networks; And Informing the mobile station whether the handover acceptance control is performed through the second medium unrelated handover message. How to perform a handover comprising a. 6. The method of claim 5, In the step (d), Monitoring the IP setting process of the mobile terminal to determine that IP allocation will be made to a new network interface card; Deleting an IP from an existing network interface card when the IP allocation is imminent; And Allocating an IP to the new network interface card when an IP allocation packet indicating the IP allocation is received; How to perform a handover comprising a. The method according to claim 6, In the step (e), Modifying the stack of IP allocation protocol information or managing a packet for confirming the final IP setting through a device driver to delay IP allocation to a new network interface card; Notifying the mobile station of information that the IP allocation is delayed; And After deleting the IP of the existing network interface card in the mobile terminal, transmitting a packet confirming the final buffered IP setting to the new network interface card. How to perform a handover comprising a. 6. The method of claim 5, The first medium unrelated handover or the second medium unrelated handover message includes a terminal ID that can be used in the handover target network.

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