KR20100118730A - Mobile terminal and method for processing handover thereof - Google Patents

Abstract

PURPOSE: A mobile telecommunication terminal and a method for processing handover of mobile communication terminal are provided to additionally include a virtual interface which is available for assigning a plurality of IP address in a interface unit of the mobile telecommunication terminal, thereby providing continuous handover between heterogeneous wireless networks. CONSTITUTION: An interface unit(240) includes interface about a wireless network of a plurality of types and virtual interface available for a plurality of IP(Internet Protocol) address allocation. An interface control unit(250) assigns the virtual interface allocated IP address assigned by connection to the predetermined telecommunication network. The interface control unit(260) assigns virtual IP address to the interface of the predetermined wireless telecommunication network. The routing table management unit updates routing table by using the IP address assigned to the virtual interface.

Description

Mobile communication terminal and handover processing method of mobile communication terminal {MOBILE TERMINAL AND METHOD FOR PROCESSING HANDOVER THEREOF}

The present invention relates to a mobile communication terminal and a handover processing method of a mobile communication terminal, and more particularly, to a mobile communication terminal and a handover processing method for supporting seamless handover between heterogeneous wireless communication networks.

Recently, various types of wireless data services such as wireless LAN, CDMA, WCDMA, and WiBro based on wireless are provided, and researches on infrastructure for ensuring mobility of wireless data services are being actively conducted. In particular, in order to guarantee the mobility of wired / wireless data services, mobile IP and proxy mobile IP (PMIP) have been proposed.

Here, the mobile IP is a standard protocol for supporting the mobility of the IP due to the movement of the terminal, and is a protocol that allows the terminal to seamlessly use the Internet even when the terminal moves out of its network area to another network. In addition, the proxy mobile IP accommodates mobility in a communication network instead of implementing a mobile IP stack in a terminal.

As such, when the mobile IP or the proxy mobile IP is used, the IP address is maintained even when the terminal moves to different subnets or heterogeneous wireless communication networks, thereby correcting connectivity between application programs.

FIG. 1 is a flowchart illustrating a handover processing procedure between heterogeneous wireless communication networks according to the prior art. In particular, FIG.

As shown, the WCDMA network includes a base station (Node-B / RNC / GSN; 110), a GGSN 120, a router (WiBro ACR; 130), a billing server (AAA; 140), and a home agent (HA; 150). It includes, through this, and handles the connection of the terminal 100 is handed over from a heterogeneous wireless communication network.

When the terminal 100 moves from the WiBro network to the WCDMA network, the terminal 100 accesses the WCDMA network through the base station 110 (S110), and then uses the following series of procedures to use user traffic in the WCDMA network. Go through

First, the terminal 100 transmits an Activate PDP context request message to the base station 110 (S112), and the base station 110 sends a PDP context request to the GGSN 120 (create PDP context request). The message is transmitted (S114). Subsequently, the GGSN 120 transmits an access request message to the charging server 140, and the charging server 140 transmits an access response message to the GGSN 120. Subsequently, the GGSN 120 transmits a binding request message to the home agent 150 (S120), and the home agent 150 transmits a binding response message to the GGSN 120. (S122). Subsequently, the GGSN 120 transmits a create PDP context response message to the base station 110 (S124). Subsequently, the base station 110 transmits a message to activate the PDP context response message to the terminal 100.

Through this process, IP-in-IP tunneling is generated between the GGSN 120 and the home agent 150. Through this, the terminal 100 is handed over to the WCDMA network to use user traffic. .

However, according to the prior art as described above, there is a limit in ensuring connectivity between applications for a terminal handed over to a heterogeneous wireless communication network. Looking at this in more detail as follows.

In order to seamlessly support an application program for a terminal handed over to a heterogeneous wireless communication network, that is, for seamless handover processing, an operating system (OS) of the terminal should support it at the stack level.

A terminal supporting a plurality of wireless communication networks includes a physical interface for each of a plurality of wireless communication networks. For example, when a predetermined terminal supports a WiBro network and a WCDMA network, a physical interface and a WCDMA for supporting a WiBro network are provided. It will include all the physical interfaces to support the network. When the terminal accesses the WiBro network, the terminal assigns an IP address assigned by the home agent to the interface of the WiBro network. When the terminal accesses the WCDMA network, the terminal assigns an IP address assigned from the home agent to the interface of the WCDMA network. User traffic of the communication network is used.

Therefore, in order to support seamless handover, the same IP address must be simultaneously assigned to two physical interfaces so that two networks can seamlessly support an application even in an overlapping area. In other words, it should be possible to assign multiple IP addresses to a single physical interface.

For example, suppose that a predetermined terminal moves from a WiBro network to a WCDMA network. When the UE located in the WiBro network moves to an overlapping area of the WiBro network and the WCDMA network, the terminal is assigned an IP address for using user traffic in the WCDMA network from the home agent.

At this time, for smooth communication in the overlapping area, the newly allocated IP address should be simultaneously assigned to the interface of the existing WiBro network as well as the interface of the WCDMA network. In addition, the IP address assigned to the interface of the existing WiBro network should be newly assigned to the WCDMA network. In other words, to support seamless handover, the same IP address must be allocated to both the WCDMA network and the WiBro network.

However, in the case of a conventional terminal using an operating system operated by Make Before Break (MBB), it is not only possible to assign a plurality of IP addresses to one physical interface, but also assign one IP address to a plurality of physical interfaces. It is also impossible to do. Therefore, when the conventional terminal using the operating system operating in the MBB method enters the overlapping area of the WiBro network and the WCDMA network, both the interface of the WiBro network and the WCDMA interface are deactivated, and the application program is disconnected.

This problem is particularly prominent in a terminal using a Windows operating system. The Windows operating system operated by the MBB method has a problem in that seamless handover cannot be provided due to the above-described problems.

Accordingly, in the case of a conventional terminal having an operating system operated by the MBB scheme, both interfaces are deactivated in the process of handover between heterogeneous networks, thereby ensuring connectivity of an application program. To this end, there is a need for a method that can support application programs seamlessly even during handover between heterogeneous wireless communication networks.

The present invention has been proposed to meet the above-described requirements, and an object of the present invention is to provide a mobile communication terminal for providing seamless handover between heterogeneous wireless communication networks using a virtual interface, and a method for processing the handover thereof.

In order to achieve the above object, the present invention provides a mobile communication terminal supporting a plurality of types of wireless communication, the interface unit including an interface for the plurality of types of wireless communication network and a virtual interface capable of assigning a plurality of IP addresses ; And an interface control unit for allocating an assigned IP address to the virtual interface by accessing a predetermined wireless communication network and allocating a virtual IP address to an interface of the predetermined wireless communication network.

The present invention also provides a handover processing method of a mobile communication terminal supporting a plurality of types of wireless communication, the method comprising: detecting a handover of the mobile communication terminal; Receiving an IP address for using the handed over wireless communication network; Allocating the allocated IP address to a virtual interface capable of assigning a plurality of IP addresses and allocating a virtual IP address to an interface of the handed over wireless communication network; And updating the routing table using the IP address assigned to the virtual interface.

According to the present invention, it is possible to provide a seamless handover between heterogeneous wireless communication networks by additionally including a virtual interface capable of assigning a plurality of IP addresses to an interface unit of a mobile communication terminal supporting a plurality of wireless communication types. That is, by allocating a pre-allocated IP address in the previous wireless communication network and a newly allocated IP address in the handovered wireless communication network to one virtual interface, the application can be provided without interruption during handover.

The above objects, features and advantages will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, whereby those skilled in the art may easily implement the technical idea of the present invention. There will be. In addition, in describing the present invention, when it is determined that the detailed description of the known technology related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a block diagram showing the configuration of a mobile communication terminal according to an embodiment of the present invention.

As shown, the mobile communication terminal 200 supporting a plurality of types of wireless communication is the communication unit 210, the handover detection unit 220, the IP address management unit 230, the interface unit 240, the interface control unit 250 ) And the routing table manager 260.

The communication unit 210 performs communication with the base station, other nodes, etc. in the mobile communication terminal 200 performs a procedure of accessing or handing over a wireless communication network. As such, the mobile communication terminal 200 may access the various types of wireless communication networks such as WLAN, CDMA, WCDMA, WiBro, and the like through the communication unit 210 to use the corresponding service.

The handover detector 220 detects a handover according to the movement of the mobile communication terminal 200, and transmits the handover to the IP address manager 220 when the handover of the mobile communication terminal 200 is detected.

The IP address management unit 230 receives and manages an IP address for using user traffic of the corresponding wireless communication network from a home agent when accessing the wireless communication network. In particular, when the handover of the mobile communication terminal 200 is detected by the handover detector 220, a new IP address for using the corresponding wireless communication network is allocated from the home agent.

The interface unit 240 includes a physical interface for each of a plurality of types of wireless communication networks supported by the mobile communication terminal 200 and a virtual interface capable of assigning a plurality of IP addresses.

Here, the virtual interface is to overcome the limitation of the operating system according to the conventional MBB method in which only one IP address is assigned to one physical interface, and is designed to be able to assign a plurality of IP addresses simultaneously. For example, by adding a virtual adapter to a network adapter area of the terminal, a virtual interface capable of assigning a plurality of IP addresses may be generated.

As such, by designing a virtual interface to allow a plurality of IP addresses to be allocated, the virtual interface may be continuously activated even when the mobile communication terminal 200 is handed over to a heterogeneous wireless communication network.

When the mobile communication terminal 200 accesses a predetermined wireless communication network, the interface controller 250 activates the corresponding interface to use user traffic. In particular, the interface controller connects to the predetermined wireless communication network and assigns the allocated IP address to the virtual interface, and assigns the virtual IP address to the interface of the predetermined wireless communication network.

For example, when the terminal 200 accesses the WiBro network, the IP address manager 230 receives an IP address for using the WiBro network from the home agent, and the interface controller 230 receives an IP address assigned from the home agent. Is assigned to the virtual interface. In this case, the interface controller 230 may generate a virtual IP address and assign the virtual IP address to an interface of the WiBro network.

The routing table manager 260 updates the routing table using the IP address assigned to the virtual interface, so that the terminal 200 can normally transmit and receive packets. For example, it is desirable to automatically assign an IP address assigned from a home agent to the default GW of a virtual interface.

According to the present invention as described above, the interface control unit 250 can maintain the connectivity of the application even during the movement, that is, handover of the terminal 200 by assigning the IP address assigned from the home agent to the virtual interface. . That is, seamless handover may be provided, which will be described in more detail as follows.

When the mobile communication terminal 200 is handed over to a heterogeneous wireless communication network, the interface controller 250 allocates an IP address allocated from the handed over wireless communication network to the virtual interface. Therefore, the virtual interface is simultaneously assigned an IP address for the wireless communication network before being handed over and an IP address for the handed over wireless communication network. That is, the virtual interface may be kept active by two IP addresses in an area where heterogeneous wireless communication networks overlap, thereby ensuring connectivity of an application program.

For example, suppose that the mobile communication terminal 200 is handed over from the WiBro network to the WCDMA network. The interface controller 250 allocates both the IP address assigned to access the WiBro network and the IP address assigned to access the WCDMA network to the virtual interface. In addition, a virtual IP address is assigned to the interface of the WiBro network and the interface of the WCDMA network.

As a result, in the process of handover from the WiBro network to the WCDMA network, the virtual interface may be activated in an overlapping area between the WiBro network and the WCDMA network. Therefore, when the user of the mobile communication terminal 200 accesses a predetermined server in the WiBro network and uses the streaming service, the user can seamlessly use the streaming service even when handed over to the WCDMA network.

3 is a flowchart illustrating a procedure of a handover processing method of a mobile communication terminal according to an embodiment of the present invention.

First, when the handover of the terminal 200 is detected by the handover detector 220 (S310), the IP address manager 230 receives an IP address for using the handovered wireless communication network from the home agent (S310). S320).

Subsequently, the interface controller 250 allocates the allocated IP address to the virtual interface of the interface unit 240 (S330). As a result, a plurality of IP addresses, i.e., IP addresses assigned in the wireless communication network before being handed over and IP addresses allocated from the handovered wireless communication network are simultaneously assigned to the virtual interface, thereby enabling seamless handover processing.

In addition, the interface controller 250 generates a virtual IP address and assigns the virtual IP address to the interface of the handed over wireless communication network.

Subsequently, the routing table manager 260 updates the routing table using the IP address assigned to the virtual interface (S340). As a result, the mobile communication terminal 200 can perform normal packet transmission and reception.

The method of the present invention as described above may be embodied as a program and stored in a computer-readable recording medium (such as a CD-ROM, a RAM, a ROM, a floppy disk, a hard disk, or a magneto-optical disk). Since this process can be easily carried out by those skilled in the art will not be described in more detail.

The present invention described above is capable of various substitutions, modifications, and changes without departing from the technical spirit of the present invention for those skilled in the art to which the present invention pertains. It is not limited by the drawings.

1 is a flow chart showing a handover processing procedure between heterogeneous wireless communication networks according to the prior art.

2 is a block diagram showing the configuration of a mobile communication terminal according to an embodiment of the present invention.

3 is a flowchart illustrating a handover processing procedure between heterogeneous wireless communication networks according to an embodiment of the present invention.

Claims (8)

In the mobile communication terminal supporting a plurality of models of wireless communication, An interface unit including an interface for the plurality of wireless communication networks and a virtual interface for assigning a plurality of IP addresses; And An interface control unit for accessing a predetermined wireless communication network, assigning an assigned IP address to the virtual interface, and assigning a virtual IP address to an interface of the predetermined wireless communication network. Mobile communication terminal comprising a. The method of claim 1, Routing table management unit for updating the routing table by using the IP address assigned to the virtual interface Mobile communication terminal further comprising. The method of claim 1, The interface control unit, When the mobile communication terminal is handed over to a heterogeneous wireless communication network, an IP address allocated from the handovered wireless communication network is allocated to the virtual interface. Mobile communication terminal. The method of claim 3, wherein The mobile communication terminal, Seamless handover processing by assigning a plurality of IP addresses to the virtual interface Mobile communication terminal. The method of claim 4, wherein The plurality of IP addresses, IP address assigned from the wireless network before handover and IP address assigned from the handed wireless network. Mobile communication terminal. In the handover processing method of a mobile communication terminal supporting a plurality of models of wireless communication, Detecting handover of the mobile communication terminal; Receiving an IP address for using the handed over wireless communication network; Allocating the allocated IP address to a virtual interface capable of assigning a plurality of IP addresses and allocating a virtual IP address to an interface of the handed over wireless communication network; And Updating a routing table using an IP address assigned to the virtual interface Handover processing method of a mobile communication terminal comprising a. The method of claim 6, The mobile communication terminal, Seamless handover processing by assigning a plurality of IP addresses to the virtual interface Handover processing method of a mobile communication terminal. The method of claim 7, wherein The plurality of IP addresses, IP address assigned from the wireless network before handover and IP address assigned from the handed wireless network. Handover processing method of a mobile communication terminal.

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