KR100700887B1 - Handoff Control Method between Mobile LAN Protocol Based LAN Network and CDM Network - Google Patents

Abstract

The present invention relates to a handoff control method between a mobile Internet protocol based WLAN network and a CDMA network, and can simultaneously perform session management for an access router (AR) of a WLAN network and a packet data serving node (PDSN) of a CDMA network. By setting the AR / PDSN to the same network so that only the L2 (Layer 2) connection is established when the WLAN network and the CDMA network are moved, a separate link-local address is formed during vertical handoff. However, since no global address is formed, the mobile node (MN) can improve service quality by reducing handoff delay and packet loss when moving between two networks.

IPv6, WLAN, CDMA, Layer 2, Layer 3, Vertical Handoff

Description

Method for vertical handoff between WLAN and CDMA based on Mobile Internet Protocol

1 is a logical network configuration for roaming,

2 is a network configuration diagram at the time of handoff;

3 is a view conceptually illustrating a process of generating a global address by setting a stateless automatic address;

4 is a flowchart illustrating a process of processing a mobile IPv6 signal;

5 is a flowchart illustrating a process of handing off from a WLAN network to a CDMA-1x network according to an embodiment of the present invention;

6 is a flowchart illustrating a handoff process from a CDMA-1x network to a WLAN network according to an embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

1: MN (Mobile Node)

2: CN (Corresponding Node)

3: AP (Access Point)

4: BTS (Base Transceiver Station)

5: AR / PDSN (Access Router / Packet Data Serving Node)

6: HA (Home Agent)

7: AAA (Authorization, Authentication and Accounting) server

8: BSC / PCF (Base Station Controller / Packet Control Function)

The present invention relates to an Internet protocol (IP) based handoff control method, and more specifically, to set up a mobile IPv6-based WLAN network and a CDMA network to the same network by connecting only L2 (Layer 2) when moving between two networks. A handoff control method between a mobile internet protocol based WLAN network and a CDMA network which reduces handoff delay and packet loss.

Efforts have been made to apply fixed mobile Internet and multimedia environments that have been applied to homes or offices to mobile systems such as vehicles. In other words, common technologies and basic technologies for performing high quality mobile services based on mobile communication networks and high-speed Internet networks have been studied. In addition, in order to solve the handoff problem due to the feature of moving, technology development is being made to provide various information services stably using wireless communication while moving.

Recently, the above-mentioned efforts have made it possible to perform high quality services in a wireless environment including mobile and internet. This is based on the development of a mobile terminal capable of accessing different IP-based networks used in the mobile network and the Internet network, and when the IP is used, a user using the mobile terminal independently uses the link layer independently. It is based on technology that can continue the service that was used. The mobile terminal includes a personal digital assistant (PDA), a laptop, and a mobile communication terminal using various access networks such as a cellular system including a wireless local area network (WLAN). Using the above IP also solves the problem of global roaming, the IETF's Mobile IP Working Group is working to standardize appropriate protocols to address the deployment of mobile IP and its shortcomings.

Meanwhile, as the number of users using the wireless Internet increases, the existing IPv4 addressing system cannot satisfy the increasing IP address requirements. Therefore, the Internet Protocol version 6 (IPv6), which is attracting attention as the next generation Internet protocol, is intended to provide mobility. Research is being actively conducted. IETF's mobile IPv6 technology is expected to be used as a standard technology for supporting mobility in the future when the Internet's IP protocol is transitioned to IPv6.

However, when the IP protocol is switched to IPv6, the control process for session establishment is described. For example, in case of WLAN and CDMA-1x, an access router (AR) and a CDMA-1x MN that accommodate WLAN MNs are described. As packet data serving nodes (PDSNs) are installed in different devices, the session management is performed separately, resulting in the delay of packet processing and the duplication of resource management during handoff. There was an inefficient disadvantage.

In addition, when a mobile node (MN) moves between WLAN and CDMA-1x, that is, heterogeneous manganese, handoff occurs in L3 (Layer 3), which takes at least 2 to 3 seconds. There was a problem that loss occurs.

Accordingly, an object of the present invention is to solve the above-mentioned problems of the prior art, and when a mobile IPv6 roaming service is performed using a WLAN network and a CDMA-1x network, the AR of the WLAN network and the PDSN of the CDMA-1x network are the same. If the MN is connected, IP configuration performs Stateless Address Auto Configure, and when the access network changes, the MN connects to L2 (Layer 2). By performing only the configuration, the MN provides a handoff control method between a mobile Internet protocol based WLAN network and a CDMA network, which improves the quality of service by reducing handoff delay and packet loss when moving between two networks.

One aspect for achieving the above object of the present invention, AR / PDSN to the same network to perform the session management for the access router (AR) of the WLAN network and the packet data serving node (PDSN) of the CDMA network at the same time The method relates to a handoff control method between a mobile internet protocol-based WLAN network and a CDMA network, wherein only a L2 (Layer 2) connection is established when the WLAN network and the CDMA network move.

Another aspect for achieving the above object of the present invention is a. Setting the access router (AR) and the packet data serving node (PDSN) to the same network to simultaneously perform session management for the access router (AR) of the WLAN network and the packet data serving node (PDSN) of the CDMA network. ; b. The mobile node forming a Link-Local Address and an IPv6 address of Layer 3, which are initially set at the same time as the Power On; c. When the access network changes, the mobile node freezes a management session of Layer 3 and performs only Layer 2 connection establishment; And d. A method for controlling handoff between a mobile internet protocol based WLAN network and a CDMA network comprising the step of performing a change between a WLAN interface and a CDMA interface in a mobile node.

Another aspect for achieving the above object of the present invention is a WLAN in an Internet protocol compatible network that performs session management for an access router (AR) in a WLAN network and a packet data serving node (PDSN) in a CDMA network together. Applied to a handoff control method between a network and a CDMA network, the mobile node checks the signal strength from an access point (AP) of a WLAN network to which the mobile node is connected and connects to the CDMA network network when the signal strength is less than or equal to a preset threshold. Attempting to establish a traffic channel between the mobile node and the CDMA network to allocate a physical channel for transmitting IP traffic; When the mobile node and the base station control period connection are established, the packet data serving node PDSN moves in response to the RP Registration Request message transmitted from the packet controller PCF of the base station controller to the packet data serving node PDSN. Registering a node number and session information to complete an RP session establishment between a packet controller (PCF) and a packet data serving node (PDSN); Attempting a link control protocol negotiation including a CHAP authentication option between a mobile node and an access router (AR) / packet data serving node (PDSN); In response to the CHAP Challenge message sent from the access router (AR) / packet data serving node (PDSN) to the mobile node, the mobile node's own ID and password are assigned to the access router (AR) / packet data serving node (PDSN). Transmitting to; Performing authentication by transmitting an ID and password to an AAA server at the AR / packet data serving node (PDSN); If authentication is successful, checking whether the mobile node is connected to and managed by the existing WLAN network and performing packet transmission to the existing WLAN interface at the same time as the buffering when the mobile node has an existing session; Sending a CHAP success message from the access router (AR) / packet data serving node (PDSN) to the mobile node; Generating a link-local address by performing an IP Control Protocol (IPCP) negotiation process between the mobile node and the access router (AR) / packet data serving node (PDSN); In response to a Router Solicitation message sent from the mobile node to the access router (AR) / packet data serving node (PDSN), the router environment (Router) from the access router (AR) / packet data serving node (PDSN) to the mobile node Transmitting an Advertisement message; And if the mobile node has the same network prefix as the previous access router in the transmitted router environment, the mobile node copies the IP configuration information of the WLAN interface to the IP configuration information of the CDMA-1x interface. It relates to a handoff control method between a base WLAN network and a CDMA network.

Another aspect for achieving the above object of the present invention is a WLAN in an Internet protocol compatible network that simultaneously performs session management for an access router (AR) in a WLAN network and a packet data serving node (PDSN) in a CDMA network. Applied to a handoff control method between a network and a CDMA network, when the mobile node communicates with the CDMA network and scans a beacon signal from a WLAN access point, the WLAN is corresponding to a WLAN signal exceeding a preset threshold. Transmitting and receiving an Association Response message between the access point and the mobile node; Performing an Extensible Authentication Protocol (EAP) authentication process between the mobile node and the WLAN access point; Transmitting a RADIUS Access Challenge message from the AAA server to the access point in response to the RADIUS Access Request message transmitted from the WLAN access point to the AAA server; Delivering the transmitted challenge value to a mobile node using an EAP Request message; Forwarding an EAP Reply / Credentials message between WLAN access points at the mobile node; Performing authentication by transmitting an ID and a password to the AAA server at the WLAN access point; If authentication succeeds, performing data encryption using a Wired Equivalent Privacy (WEP) algorithm, and defining to use the fixed state by sharing the encryption key; When requesting the use of the WEP to the mobile node, transmitting the WEP key to the mobile node by including a WEP key in an EAPOW Wireless Key (EAPOW Key) message at a WLAN access point; When the connection is complete, the mobile node at the access router (AR) / packet data serving node (PDSN) in response to a Router Solicitation message sent from the mobile node to the access router (AR) / packet data serving node (PDSN). Delivering a Router Advertisement message to the router; And if the mobile router has the same network prefix as the previous access router in the transmitted router environment, the mobile node copies the IP configuration information of the CDMA interface to the IP configuration information of the WLAN interface. A handoff control method between a protocol based WLAN network and a CDMA network is provided.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

1 is a logical network diagram for roaming. Referring to FIG. 1, a system in which the present invention is implemented includes a mobile node (hereinafter referred to as “MN”) 1, a counterpart node (hereinafter referred to as “CN”) 2, Access Point (Access Point (hereinafter referred to as "AP")) (3), Base Station (Base Transceiver Station (hereinafter referred to as "BTS") (4), Access Router / Packet Data Serving Node ; Hereinafter referred to as "AR / PDSN" (5), Home Agent (hereinafter referred to as "HA") (6), Authentication Server (Authorization, Authentication and Accounting; hereinafter referred to as "AAA Server" (7), a base station controller / packet control function (hereinafter referred to as "BSC / PCF") (not shown).

The Mobile Node (MN) 1 refers to a mobile node that provides mobile IPv6 client functionality.

CN (Corresponding Node) (2) means the communication node of the other side of the MN (1).

The AP 3 refers to a WLAN device that connects a wired LAN to a wireless LAN.

The base transceiver station (BTS) 4 refers to a base station located between the MN 1 and the BSC / PCF 8 to provide a mobile communication service to the MN 1. Here, the radio section interface between the BTS 4 and the MN 1 conforms to the IS-2000 standard.

The unique function of the access router (AR) is a node functioning as a default router of the MN 1, and the MN 1 attempts a Layer 3 handoff when the default router is changed. In addition, the unique function of the Packet Data Serving Node (PDSN) serves as a PPP access server in a CDMA-1x network, provides an R-P interface that is a connection interface with a PCF, and performs R-P session management. The AR (Access Router) and PDSN (Packet Data Serving Node) provided by the present invention are configured as an integrated device, and the integrated AR / PDSN 5 performs the unique functions of the AR and the PDSN together. The function of the AR / PDSN 5 will be described in detail later.

The home agent (HA) 6 is a router on a home link that registers and manages a care of address (CoA) of the MN 1. IP mobility management is performed for the MN 1 when it is away from the home link of the MN 1. The CoA means an IPv6 address set on the outer link while the MN 1 is on the outer link. On the other hand, HoA (Home Address) is an IPv6 address assigned to the MN 1 in the home link means a fixed address that does not change from a power on time to a power off time.

On the other hand, L2 (Layer 2) handoff refers to a process of changing an existing link layer connection to another link layer connection when the MN 1 moves. For example, the layer 2 handoff is when the MN 1 changes the AP 3 in the WLAN or the MN 1 changes the BTS 4 in CDMA-1x.

When the AR is changed in the WLAN during L3 (Layer 3) handoff, the MN 1 performs an address auto configuration, and then performs a binding update to the HA 6. In the case of L3 (Layer 3) handoff, in CDMA, the PDSN is changed and performed, and the binding update is performed to the HA 6 in the same manner as the WLAN.

A handoff control method between the mobile Internet protocol based WLAN network and the CDMA network of the present invention configured as described above will be described.

First, in order to carry out the present invention, the present invention is carried out under the following conditions.

1. To implement mobile IPv6 roaming service using WLAN network and CDMA-1x network, implement AR of WLAN network and PDSN of CDMA-1x network as the same equipment, and simultaneously manage sessions through this equipment. To be set.

In this state, when the MN (1) makes a connection, the IP configuration performs Stateless Address Auto Configure, and when the access network is changed, the MN (1) only establishes the L2 (Layer 2) connection, and L3. (Layer 3) Omit the setting process. It provides fast and low packet loss mobile IPv6 service by omitting L3 (Layer 3) process which takes at least 2-3 seconds. That is, in case of roaming service using WLAN network and CDMA-1x network, even if MN (1) moves between two networks by setting AR of WLAN network and PDSN of CDMA-1x network to same network, L2 (Layer 2) ), Only the connection setting is made and the connection setting of L3 (Layer 3) is omitted. In this way, the MN 1 can improve the quality of service by reducing handoff delay and packet loss when moving between two networks.

2. As described above, even if the AR / PDSN 5 implemented in the same equipment has a handoff, the management session of L3 (Layer 3) is not changed. In other words, when changing from WLAN interface to CDMA-1x interface or vice versa for handoff, MN 1 changes interface without generating address and performing DAD (Duplicate Address Detection).

3. Prefix information of the AR / PDSN 5 included in the Router Advertisement message is the same.

4. The MN 1 simultaneously mounts the WLAN interface and the CDMA-1x wireless modem interface, and simultaneously scans the AP 3 signal and the BTS 4 signal for handoff. When moving two heterogeneous manganese, only L2 (Layer 2) handoff is performed and L3 (Layer 3) handoff is not performed.

5. The WLAN network shall be included in the coverage of the CDMA-1x network.

6. In case of moving heterogeneous manganese, MN (1) switches network interface and AR does not perform L3 (Layer 2) handoff but only L3 (Layer 3) handoff. Change the packet transmission.

2 is a network configuration diagram at the time of handoff. Referring to FIG. 2, the solid line means an upward vertical handoff, which communicates in a WLAN area, and the signal strength of the AP 3 is determined by a certain threshold. This means that handoff is performed to the CDMA-1x network when it falls below the threshold.

On the other hand, the dotted line means Downward Vertical Handoff, which means downlink Vertical Handoff, when communicating in a CDMA-1x network and entering a WLAN service area, that is, a Hot Spot area. do.

3 is a diagram conceptually illustrating a process of generating a global address by using a conventional stateless automatic address setting. FIG. 3 is a diagram illustrating a process of forming an IPv6 address of the MN 1, and in IPv6, the MN 1 generates a link-local address used only in the same subnet while activating a network interface. To perform the DAD. Here, DAD (Duplicate Address Detection) means a process of verifying whether another node is using an address formed by another node after the address of MN 1 is formed.

As such, the DAD process broadcasts its own link-local address to all hosts on the same subnet to determine if there is a host using a link-local address that is duplicated with itself. do.

If there is no response for a certain period of time, it is assumed that there is no node using the same link-local address as its own, and a link-local address is generated.

On the other hand, for CoA formation in mobile IPv6, that is, in IPv6, MN (1) is created with 64 bits of Network Prefix and its Layer 2 address in Router Advertisement message received from AR for address generation. The IEEE EUI 64-bit format is combined to form a 128-bit address.

As shown in FIG. 3, when the MN 1 does not receive a Router Advertisement message transmitted by an AR for a certain period of time or a Network Prefix is needed immediately, the MN 1 sends an AR Router Solicitation message to the AR. Send immediately to (S1).

After receiving the Router Solicitation message, the AR includes its network prefix in the Router Advertisement message and sends it to the MN 1 (S2).

The MN 1 forms an IPv6 address by combining the network prefix and the IEEE EUI 64 format formed by its link-layer address (S3).

In this way, a global address is formed by stateless address autoconfiguration. In the stateless automatic address setting, the MN 1 combines the network prefix transmitted by the router and its link-layer address to form its own Layer 3 IP address.

As described above, the handoff control method between the mobile Internet protocol based WLAN network and the CDMA network of the present invention is a separate link-local address at the time of the vertical handoff. It is unnecessary to form an address or form a global address. This is because only the handoff of Layer 2 proceeds and no handoff of Layer 3 occurs.

For this reason, considering that the handoff of the layer 3 generally takes about 2 to 3 seconds, the present invention shortens the overall handoff time by avoiding the handoff process of the layer 3, and prevents packet loss during the handoff. It can be seen that it can be almost prevented.

4 is a flowchart illustrating a conventional mobile IPv6 signal processing process. Referring to FIG. 4, the MN 1 sends a Router Solicitation message to the AR when it does not receive a Router Advertisement message for a certain period of time or wants to receive it quickly (S10).

Accordingly, the AR includes a network prefix in the Router Advertisement message and sends it to the MN 1 (S11).

If the network prefix received by the MN 1 is different from the previous one, the MN 1 generates a link-local address and then performs a DAD (S12).

After performing the DAD, the MN 1 generates a CoA (S13). The DAD for CoA is optional.

Subsequently, the MN 1 sends a binding update message to the HA 6 to inform the HA 6 to update the table combining its CoA with its HoA (S14).

The HA 6 responds to the MN 1 when the update is completed (S15).

As a result, the CN 2 and the MN 1 perform communication. At this time, HA 6 intercepts the packet going from CN 2 to MN 1 and delivers it to MN 1 (S16 to S17). That is, only the packet first transmitted from the CN 2 is delivered to the MN 1 via the HA 6.

On the other hand, if it is determined that the routing optimization is necessary in the CN (2), sends a binding request (Binding Request) message to the MN (1) and requests to send a binding update (Binding Update) message to the CN (S18) (S18). .

The MN 1 sends a binding request message to the CN 2 and registers it with the CN 2 (S19).

When this process is completed, MN (1) and CN (2) communicates directly without going through the HA (6) until the handoff occurs (S20).

3 and 4, a handoff control method between the mobile Internet protocol based WLAN network and the CDMA network will be described.

5 is a flowchart illustrating a process of handing off from a WLAN network to a CDMA-1x network. As shown in FIG. 5, first, the MN 1 detects that the strength of a signal coming from the currently accessed AP 3 or another AP 3 falls below a preset threshold (S30).

If the threshold is less than or equal to the set value, the MN 1 attempts to access the CDMA-1x network by sending an Origination message to the BSC / PCF 8 via the base station (S31).

Therefore, BSC / PCF (8) sends a base station acknowledgment (Base Station Ack Order) to MN (1), and then a traffic channel is established between MN (1) and BSC / PCF (8) to physically transmit IP traffic. Channel allocation is completed (S32).

When the connection between the MN (1) and the BSC / PCF (8) is completed, the BSC (PCF) sends a RP Registration Request message to the PDSN (AR), and the PDSN (AR) receives the number of the MN (1). After registering the session information and the like, a RP Registration Reply message is transmitted to the PCF (BSC), and the BSC / PCF 8 completes the establishment of the RP session to the AR / PDSN 5 (S33).

Subsequently, PPP is established between the MN 1 and the AR / PDSN 5, and the MN 1 attempts an LCP negotiation (including a CHAP authentication option) with the AR / PDSN 5 (S34). That is, when the AR / PDSN (5) sends a Link Control Protocol (LCP Configure Request) message to the MN (1), if the MN (1) is set to use the Challenge Handshake Authentication Protocol (CHAP) here ) Sends an LCP Configure Noacknowledgement message to the AR / PDSN (5), which in turn sends an LCP Configure Request message with the missing authentication option. In response, the MN 1 sends a link control protocol configuration response (LCP Configure Acknowledgement) message.

Next, the AR / PDSN 5 sends a CHAP Challenge message to the MN 1 (S35). MN 1 sends its ID and password to AR / PDSN 5 (S36).

Subsequently, the authentication process is performed. The AR / PDSN (5) is a RADIUS client of the AAA (Authorization, Authentication and Accounting) server 7 and receives the ID and password information received from the MN 1 as an AAA server ( Send a RADIUS Access Request (RADIUS Access Request) message to deliver to 7) (S37). In response, the AAA server 7 sends a RADIUS Access Accept message to the AR / PDSN 5 (S38).

If the authentication is successful, AR / PDSN (5) checks whether it is MN (1) that is connected and managed by WLAN network. If MN (1) has an existing session, buffering starts. The transmission to the network is simultaneously performed (S39).

Thereafter, the AR / PDSN 5 sends a CHAP success message to the MN 1 (S40).

Next, the MN 1 performs an IPCP protocol negotiation process with the AR / PDSN 5 to generate a link-local address (S41).

Subsequently, the MN 1 sends a Router Solicitation message to the AR / PDSN 5 (S42). In response to the Router Solicitation message to the AR / PDSN 5, a Router Advertisement message is sent to the MN 1 (S43).

The MN 1 copies the IP configuration information of the WLAN interface to the IP configuration information of the CDMA-1x interface if it has the same network prefix as the previous AR. At this time, the mobile IPv6 related session information is maintained as it is. At this time, the DAD process does not exist. If it does not have the same network prefix as the previous AR, the mobile IPv6 handoff procedure is performed as it is (S44).

The MN 1 then sends a Switch Interface Request message to the AR / PDSN 5 (S45). In response to the Switch Interface Request message, the AR / PDSN 5 sends a Switch Interface Reply message to the MN 1 (S46). The AR / PDSN 5 transmits the buffered data to the CoA of the MN 1 (S47).

6 is a flowchart illustrating a process of handing off from a CDMA-1x network to a WLAN network. Referring to FIG. 6, the MN 1 continuously scans a beacon signal transmitted by the WLAN AP 3 while communicating through a CDMA-1x interface (S50).

Through the scanning, it is detected whether a signal transmitted by the WLAN AP 3 is greater than or equal to a preset threshold (S51).

At this time, when a signal above the preset threshold is detected, the MN 1 selects the WLAN AP 3 with the strongest beacon signal and sends an association response message (S52). ). The WLAN AP 3 responds to the MN 1 in an association response message (S53).

Thereafter, the user authentication process is performed. First, the MN 1 sends an EAPOL (Extensible Authentication Protocol over LAN) Start message to the WLAN AP 3 for EAP (Extensible Authentication Protocol) authentication (S54). . In response, the WLAN AP 3 transmits an EAP Request / Identity (EAP Request) message to the MN 1 (S55), and the MN 1 transmits its ID to the EAP Response / ID (EAP Reply / It responds to the WLAN AP 3 as an Identity) message (S56).

Subsequently, the WLAN AP 3 sends a RADIUS Access Request message to the AAA server 7 (S57). In response, the AAA server 7 sends a RADIUS Access Challenge message to the AP 3 (S58).

The WLAN AP 3 transmits the challenge value received in step S58 to the MN 1 using an EAP Request message (S59). The MN 1 sends an EAP Reply / Credentials message to the AP 3 for authentication (S60).

Subsequently, the WLAN AP 3 sends a RADIUS Access Request message to the AAA server 7 in order to transfer the received user ID and password to the AAA server 7 (S61). In response, the AAA server 7 transmits a RADIUS Access Accept message to the WLAN AP 3 when the MN 1 is successfully authenticated (S62). Next, the WLAN AP 3 sends an EAP Success message to the MN 1 indicating the successful authentication (S63).

In the IEEE 802.11 standard, data encryption is performed using a WEP (Wired Equivalent Privacy) algorithm, and the encryption key is defined to be shared and used in a fixed state.

On the other hand, when requesting the use of the WEP to the MN (1), the WLAN AP (3) sends to the MN (1) including the WEP key in the EAPOW (EAPOW (EAP over Wireless) Key) message (S64). When the connection is completed, the MN 1 sends a Router Solicitation message to the AR / PDSN 5 (S65).

The AR / PDSN 5 sends a Router Advertisement message to the MN 1 (S66). At this time, the MN 1 copies the IP setting of the CDMA-1x interface to the WLAN interface if the network prefix of the target AR / PDSN 5 is the same as before (S67).

In response, the MN 1 sends a Switch Interface Request (SIRQ) message to the AR / PDSN 5 (S68). In response to the Switch Interface Request message, the AR / PDSN 5 responds to the MN 1 as a Switch Interface Reply (SIRP) message upon receiving the SIRQ message (S69). Simultaneously with the step S69, the PDSN sends a packet destined for the MN 1 to the WLAN interface (S70).

The present invention is not limited to the above-described embodiments, and it will be apparent that many modifications are possible by those skilled in the art within the technical spirit of the present invention.

As described above, the method for controlling handoff between a mobile Internet protocol-based WLAN network and a CDMA network according to the present invention may include forming a separate link-local address or vertical at the time of vertical handoff. It is possible to shorten the overall handoff time and to prevent packet loss due to the handoff, by eliminating the need for an address (Global Address) to avoid the handoff process of Layer 3, which takes about 2 to 3 seconds.

Claims (14)

delete A handoff control method between a WLAN network and a CDMA network in an Internet protocol compatible network, a. Setting the access router (AR) and the packet data serving node (PDSN) to the same network to simultaneously perform session management for the access router (AR) of the WLAN network and the packet data serving node (PDSN) of the CDMA network. ; b. The mobile node forming a Link-Local Address and an IPv6 address of Layer 3, which are initially set at the same time as the Power On; c. When the access network changes, the mobile node freezes a management session of Layer 3 and performs only Layer 2 connection establishment; And d. Performing a change between a WLAN interface and a CDMA interface at the mobile node A handoff control method between a WLAN network and a CDMA network in an Internet protocol compatible network, comprising: a. The method of claim 2, wherein b. The steps are, Generating a link-local address used only in the same subnet while activating a network interface when the mobile node connects to a WLAN network or a CDMA network; And The Mobile Node sends a Router Solicitation message to the AR / PDSN to receive its Network Prefix and Router Advertisement messages to the AR / PDSN to receive the Network Prefix and itself. Forming an IPv6 address of Layer 3 by combining the IEEE EUI 64 format formed by the link-layer address of A handoff control method between a WLAN network and a CDMA network in an Internet protocol compatible network, characterized in that consisting of. The method of claim 3, wherein the prefix information of the AR / PDSN included in the Router Advertisement message is the same. . The method of claim 2, wherein the mobile node, Equipped with a WLAN interface and a CDMA wireless modem interface simultaneously; A method for controlling handoff between a WLAN network and a CDMA network in an internet protocol compatible network, comprising simultaneously scanning an access router signal and a base station signal to perform a handoff between the WLAN network and the CDMA network. 3. The method of claim 2, wherein the WLAN network is included in the coverage of the CDMA network. The method of claim 2, wherein the mobile node performs network interface switching when moving between heterogeneous networks in the same subnet, and the access router transmits a packet to the mobile node to the selected interface. Handoff Control Method between WLAN Network and CDMA Network in WLAN. A method for controlling handoff between a WLAN network and a CDMA network in an internet protocol compatible network which performs session management for an access router (AR) in a WLAN network and a packet data serving node (PDSN) in a CDMA network, The mobile node and the CDMA network traffic channel are established by checking the signal strength from the access point (AP) of the WLAN network to which the mobile node is connected and attempting to access the CDMA network when the signal strength is less than or equal to a preset threshold. Allocating a physical channel for transmitting IP traffic; When the mobile node and the base station control period connection are established, the packet data serving node PDSN corresponds to a RP Registration Request message transmitted from the packet controller PCF of the base station controller to the packet data serving node PDSN. Registering the number and session information of the mobile node to complete an RP session establishment between a packet controller (PCF) and a packet data serving node (PDSN); Attempting a link control protocol negotiation including a CHAP authentication option between the mobile node and an access router (AR) / packet data serving node (PDSN); In response to the CHAP Challenge message transmitted from the access router (AR) / packet data serving node (PDSN) to the mobile node, the mobile station owns its ID and password to the access router (AR) / packet data serving node ( Transmitting to PDSN); Performing authentication by transmitting an ID and password to an AAA server at the AR / packet data serving node (PDSN); If the authentication is successful, checking whether the mobile node is connected to and managed by the existing WLAN network and performing packet transmission to the existing WLAN interface simultaneously with buffering when the mobile node has an existing session; Sending a CHAP success message from an access router (AR) / packet data serving node (PDSN) to the mobile node; Generating a link-local address by performing an IPCP protocol negotiation between the mobile node and an access router (AR) / packet data serving node (PDSN); A router environment from an access router (AR) / packet data serving node (PDSN) to the mobile node in response to a router solicitation message sent from the mobile node to an access router (AR) / packet data serving node (PDSN). Transmitting a Router Advertisement message; And If the mobile router has the same network prefix as the previous access router in the transmitted router environment, the mobile node copies IP configuration information of the WLAN interface to IP configuration information of the CDMA-1x interface; A handoff control method between a WLAN network and a CDMA network in an Internet protocol compatible network, characterized in that. The method of claim 8, wherein before an authentication process for delivering the ID and password, Sending a RADIUS Access Request message to the AAA server at an access router (AR) / packet data serving node (PDSN), which is a RADIUS client of the AAA server; Sending a RADIUS Access Accept message from the AAA server to the Access Router (AR) / Packet Data Serving Node (PDSN). A method for controlling handoff between a WLAN network and a CDMA network in an Internet protocol compatible network, further comprising: 9. The method of claim 8, wherein in the transmitted router environment does not have the same network prefix as the previous access router, The mobile node sending a switch interface request message to an access router (AR) / packet data serving node (PDSN); Sending a Switch Interface Reply message from an access router (AR) / packet data serving node (PDSN) to the mobile node in response to the Switch Interface Request message; And An access router (AR) / packet data serving node (PDSN) transmitting the buffered data to a care of address (CoA) of the mobile node; A method for controlling handoff between a WLAN network and a CDMA network in an Internet protocol compatible network, characterized by A handoff control method between a WLAN network and a CDMA network in an internet protocol compatible network which simultaneously performs session management for an access router (AR) of a WLAN network and a packet data serving node (PDSN) of a CDMA network, When the mobile node communicates with the CDMA network and scans a beacon signal from the WLAN access point and the beacon signal is greater than or equal to a preset threshold, an association response between the WLAN access point and the mobile node. Sending and receiving a message; Proceeding with an Extensible Authentication Protocol (EAP) authentication process between the mobile node and a WLAN access point; Transmitting a RADIUS Access Challenge message from the AAA server to the access point in response to the RADIUS Access Request message transmitted from the WLAN access point to the AAA server; Delivering the transmitted challenge value to the mobile node using an EAP Request message; Forwarding, by the mobile node, an EAP Reply / Credentials message between WLAN access points; Performing authentication by transmitting an ID and a password to the AAA server at the WLAN access point; If authentication succeeds, performing data encryption using a Wired Equivalent Privacy (WEP) algorithm, and defining to use the fixed state by sharing the encryption key; Sending a request to the mobile node to include the WEP key in an EAPOW key (EAP over Wireless Key) message at a WLAN access point; When the connection is completed, the access router (AR) / packet data serving node (PDSN) responds to a router solicitation message sent by the mobile node to the access router (AR) / packet data serving node (PDSN). Delivering a Router Advertisement message to the mobile node; And If the mobile router has the same network prefix as the previous access router in the transmitted router environment, the mobile node copies the IP configuration information of the CDMA interface to the IP configuration information of the WLAN interface; A handoff control method between a WLAN network and a CDMA network in an Internet protocol compatible network, comprising: a. The method of claim 11, wherein the EAP authentication process between the mobile node and the WLAN access point comprises: Sending an EAPOL Extensible Authentication Protocol over LAN Start message from the mobile node to a WLAN access point; Sending an EAP Request / Identify (EAP Request) message to the mobile node at a WLAN access point; And Responding to the WLAN access point from the mobile node with its ID in an EAP Reply / Identity message A handoff control method between a WLAN network and a CDMA network in an Internet protocol compatible network, characterized in that consisting of. The method of claim 11, wherein before the authentication process for ID and password transfer in the authentication process between the WLAN access point and the AAA server, Forwarding a RADIUS Access Request message from the WLAN access point to the AAA server; Sending a RADIUS Access Accept message from the AAA server to the WLAN access point if authentication is successful; And Sending an EAP Success message from the WLAN access point to the mobile node A method for controlling handoff between a WLAN network and a CDMA network in an Internet protocol compatible network, further comprising: 12. The method of claim 11, wherein in the transmitted router environment does not have the same network prefix as the previous access router, The mobile node sending a switch interface request message to an access router (AR) / packet data serving node (PDSN); Sending a Switch Interface Reply message from an access router (AR) / packet data serving node (PDSN) to the mobile node in response to the Switch Interface Request message; And An access router (AR) / packet data serving node (PDSN) transmitting the buffered data to a care of address (CoA) of the mobile node; A method for controlling handoff between a WLAN network and a CDMA network in an Internet protocol compatible network, characterized by

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