KR101035817B1 - Method for forming internet address of mobile station in wireless internet service - Google Patents

Abstract

The present invention relates to a method for reducing delay due to address formation of an Internet Protocol (IP) when a mobile terminal moves on a mobile network for a wireless Internet service. The new Internet address of the mobile terminal in the external network is formed from the interface identifier identifying the PPP link with the packet data service node being accessed and the prefix value of the packet data service node. After the PPP connection with the mobile terminal, the packet data service node remains fixed without changing the initially selected basic interface identifier. The mobile terminal changes its interface identifier to the interface identifier value received from the packet data service node. After determining the interface identifier in the mobile terminal, the packet data service node provides its prefix value to the mobile terminal. The mobile terminal forms a new internet address with the determined interface identifier and the prefix value of the packet data service node. This invention minimizes the loss of IP packets by reducing the delay that occurs when a MIPv6 mobile terminal forms an IPv6 CoA over a PPP connection.

Mobile IP, MIPv6, PPP, IPv6CP, CoA, Configuration Option

Description

Method of forming internet address of mobile terminal for wireless internet service {METHOD FOR FORMING INTERNET ADDRESS OF MOBILE STATION IN WIRELESS INTERNET SERVICE}             

1 is a diagram schematically illustrating a network structure of mobile IPv6.

2 is a state transition diagram illustrating PPP connection steps for a mobile Internet service.

3 is a message flow diagram illustrating a procedure of forming an IP address by a mobile terminal using MIPv6.

4 is a message flow diagram illustrating a procedure for a mobile terminal using MIPv6 to form an IP address on a PPP link.

5 is a message format of a MIPv6 configuration option in accordance with a preferred embodiment of the present invention.

6A-6C are message flow diagrams illustrating operations when using the MIPv6 configuration option.

7 is a state transition diagram showing a setting option processing operation of a PDSN according to a preferred embodiment of the present invention.

8 is a state transition diagram showing a setting option processing operation of a mobile terminal according to an embodiment of the present invention.

9 is a diagram illustrating an address forming operation according to a preferred embodiment of the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to wireless Internet services, and more particularly, to a method for reducing delay due to address formation of an Internet Protocol (hereinafter referred to as IP) when a mobile terminal moves on a mobile network.

With the miniaturization of computers and the availability of Internet access through small portable terminals, mobility support for this is inevitable. As a result, efforts to support mobility in an IP-enabled Internet environment are being made by the Internet Engineering Task Force (IETF) 's IP routing for Wireless / Mobile Hosts Charter. Since the standard was established, work on mobility support of mobile IPv6 has been made.

Mobile IPv4 (hereinafter referred to as MIPv4) operates when the mobile terminal moves to an external network. When a mobile terminal connected to an external network receives a response to an agent solicitation message or an advertisement message periodically transmitted from an external agent (FA) in the external network, the mobile terminal transmits a message to the external network. It knows that it is connected and obtains a new IP address in conjunction with an external agent. The mobile terminal registers its new IP address with the home agent in association with the external agent. The IP address obtained from the external network is called a care-of-address (CoA). As a result, the home agent determines the location of the mobile terminal and delivers data transmitted to the home address of the mobile terminal to the CoA bound to the home address. In this case, the external agent uses tunneling.

In Mobile IPv6 (hereinafter referred to as MIPv6), a mobile terminal handles the role of an external agent without an external agent, and includes routing optimization by default, Router Solicitation (RS) message or Router Advertisement. Message to know which network the mobile terminal is connected to and uses the automatic address setting function to obtain a CoA. In addition, Mobile IPv6 expresses the IP address in 128 bits, which is greatly increased compared to 32 bits of Mobile IPv4, simplifying the protocol header and supporting QoS. It also supports Authentication Header (AH) and Encrypted Security Payload (ESP) for security.

1 schematically illustrates the network architecture of Mobile IPv6, in which three nodes 22, 24, and 26 are connected to the Internet 10 via three links. Each link is connected to the Internet 10 by a corresponding Access Router (AR) 12, 14, 16. The home agent 26 acts as a proxy while the mobile terminal 22 is out of the home area and is responsible for intercepting and tunneling from the partner node 24 to the mobile terminal 22. 22) to manage the position. Link A, which is connected to the home agent 26, is also called a home link.

In a code division multiple access (CDMA) 2000 system, a mobile terminal is connected to the Internet by a packet data serving node (hereinafter referred to as PDSN). The PDSN serves as both a PPP server and an access router (AR). Whenever the mobile station changes the PDSN during the wireless Internet service, a new IP address, that is, a CoA, is allocated or formed, using a PPP link with the PDSN. The CoA is formed of a combination of a unique interface identifier of a mobile terminal and a prefix value of an access router, that is, a PDSN, connected to the mobile terminal. However, when MIPv6 CoA is formed using PPP in MIPv6, a lot of delay may occur in address formation for the following reasons.

When establishing the PPP link, the mobile terminal and the PDSN on both sides of the PPP link transmit their own basic interface identifiers in the Configure-Request IPv6 control protocol message to negotiate the interface identifiers. Is the same as its own, suggesting a different interface identifier. Since the interface identifier should be single for the PPP link, when the negotiation is completed, different interface identifier values should be selected at both ends of the PPP link. However, if the mobile terminal and the PDSN use different basic interface identifiers in the first place, two IPv6 control protocol messages according to the corresponding interfaces are transmitted to each other, so that it takes time to receive two IPv6 control protocol messages. do. If the first two interface identifiers are the same, the interface identifier negotiation takes longer.

In case of general IPv6 terminal, Internet interface is newly started, so this interface identifier negotiation does not affect service. However, interface identifier performed when IPv6 CoA is formed through new PPP connection in the middle of service like MIPv6. Negotiation causes service delays until the mobile terminal resumes service after movement and causes data corruption due to packet loss.

The mobile terminal uses the following two methods in obtaining a prefix from an access router (AR) or a PDSN. In other words, the first mobile terminal transmits ICMP (Internet Control Message Protocol for IPv6) RS (Router Solicitation) to AR / PDSN to induce ICMP Router Advertisement (AR) of AR / PDSN. Wait for the periodic ICMP RA of the / PDSN. However, both of these methods incur significant delays, which can cause service delays and packet data corruption.

Accordingly, an object of the present invention, which is designed to solve the problems of the prior art operating as described above, is to minimize the loss of IP packets by reducing the delay incurred when the MIPv6 mobile terminal forms an IPv6 CoA through a PPP connection. To provide a way.

Another object of the present invention relates to a method of forming CoA without delay through PPP when maintaining layer 3 connectivity using MIPv6 in a CDMA 2000 system.

It is still another object of the present invention to simplify a procedure of assigning an interface identifier between a mobile terminal and an AR / PDSN, and to use an IPv6 control protocol configuration option for providing a prefix of an AR / PDSN to a mobile terminal through a link control protocol. will be.

In order to achieve the above object, an embodiment of the present invention provides a method for forming an Internet address of a mobile terminal for receiving a wireless Internet service in a mobile communication system in which the mobile terminal accesses the Internet by packet data service nodes. To

A mobile terminal newly accessing a packet data service node, and transmitting a basic interface identifier identifying the link to the packet data service node to form a link with the new packet data service node;

Sending a configuration-acknowledge message to the packet data service node when a configuration-nake message is received from the packet data service node requesting to change the interface identifier;

Sending a setup-request message to the packet data service node including a new interface identifier in response to the setup-nak message;

When a setup-arc message is received from the packet data service node that includes the prefix value of the packet data service node in response to the setup-request message that includes the new interface identifier, the new interface identifier and the prefix value are combined. And forming a new internet address of the mobile terminal.

Another embodiment of the present invention provides a method for providing a wireless Internet service to a mobile terminal by a packet data service node in a mobile communication system in which the mobile terminal connects to the Internet by a packet data service node.

Transmitting a basic interface identifier identifying the link to the mobile terminal to form a link with a mobile terminal that has newly accessed a packet data service node;

When the setup-request message including the interface identifier of the mobile terminal is received from the mobile terminal, comparing the interface identifier of the mobile terminal with the basic interface identifier;

If the interface identifier of the mobile terminal is the same as the basic interface identifier, transmitting a setup-nak message including the new interface identifier selected for the mobile terminal to the mobile terminal;

If the interface identifier of the mobile terminal is not the same as the basic interface identifier, transmitting a setup-acknowledge message including a prefix value of the packet data service node to the mobile terminal;

When the mobile station receives the setup-acknowledgement message, the default interface identifier value is determined to be an interface identifier to be used later.

Hereinafter, with reference to the accompanying drawings will be described in detail the operating principle of the preferred embodiment of the present invention. In the following description of the present invention, detailed descriptions of well-known functions or configurations will be omitted if it is determined that the detailed description of the present invention may unnecessarily obscure the subject matter of the present invention. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

The present invention to be described later largely comprises a mobile terminal and a PDSN to which the mobile terminal makes a PPP connection. The mobile terminal uses MIPv6, and the PDSN serves as both a PPP server and an access router. Since the mobile terminal uses IPv6 as a three-layer protocol, it forms a new Internet address every time it connects to the PDSN. The new IPv6 address, i.e., CoA, of the mobile terminal in the external network is formed from the interface identifier identifying the PPP link with the packet data service node being accessed and the prefix value of the packet data service node. Thus, the PDSN provides the interface identifier and prefix to the mobile terminal through a PPP connection.

2 shows PPP access phases for a mobile Internet service. Here, the PPP connection is divided into five steps, through which the mobile terminal of the PPP end forms a link with the PDSN and is assigned or formed with an IP address.

In the " Dead " step 101, no link is established between the mobile terminal across the PPP and the PDSN. The mobile terminal accesses the new PDSN and transitions to " Establish " step 103 when the link is " UP ".

In step 103, a link is established between the mobile terminal across the PPP and the PDSN. In the " Establish " step 103, link control protocol (LCP) messages are exchanged between the mobile terminal and the PDSN to form a link. If the link is " OPEN ", the " Authenticate " Transition If the link formation fails during the LCP message exchange, the process returns to " Dead "

In step 105, the mobile terminal is authenticated for the PPP connection. This step 105 may not exist in some cases, and if present, the terminal may be referred to as a password authentication protocol (hereinafter referred to as PAP) or a challenge-handshake authentication protocol (hereinafter referred to as CHAP). You will be authenticated using. If the authentication fails, the process transitions to the "Terminate" step 109 to terminate the PPP connection. If the authentication succeeds, the process transitions to the "Network" step 107.

In step 107, a three-layer protocol to be used by the mobile terminal is set. In case of IPv4, an IPv4 address is assigned to a mobile terminal using IP Control Protocol (IPCP). In case of IPv6, a configuration option of RFC 2472 IPv6 Control Protocol (IPv6CP) is used. The "Interface-Identifier" is used to assign an Interface Identifier for IPv6 address formation. The IPv6 control protocol provides two configuration options: "Interface Identifier" and "IPv6 Compression-Protocol." The wireless Internet service of the mobile terminal is made in this step 107. IP packets exchanged between the mobile terminal and the PDSN are exchanged according to the LCP. The " Network " step 107 continues until the mobile terminal terminates the PPP connection with the PDSN or the timer value expires.

In step 109, the PPP connection between the mobile terminal and the PDSN is terminated. In this step 109, the link "UP" in the "Dead" step 101 is "Down".

According to the type of three-layer protocol used by the mobile terminal, PPP provides the mobile terminal with an IP address as follows.

In the case of IPv4, the PDSN assigns a new IPv4 address to a mobile terminal by including a new IPv4 address in a message of a link control protocol in step 107 of the PPP link.

In the case of IPv6, the PDSN transfers the new interface identifier to the mobile terminal by including the new interface identifier in the message of the link control protocol in step 107 of the PPP link. The mobile terminal generates a link-local address using the interface identifier, and automatically forms an IPv6 address using the prefix and the interface identifier of the router advertisement message received from the PDSN. Stateless Address Auto-configuration.

In the case of MIPv4, the mobile station uses an IPv4 address allocated from the PDSN as a new CoA through the same procedure as IPv4, and registers the CoA with the home agent HA using a Registration Request (RRQ) message.

In the case of MIPv6, the mobile terminal acquires an IP address according to the following procedure.                     

3 is a message flow diagram illustrating a procedure of forming an IP address by a mobile terminal using MIPv6. Here, the operation of the mobile terminal independent of the link protocol is shown. Accordingly, the target to which the mobile terminal connects becomes a general access router (AR), and the home agent (HA) and the partner node (CN) participate in the address registration operation of the MIPv6.

In step 201, the mobile terminal moves from the previously accessed access router and accesses the new access router. In step 203, the mobile station transmits an ICMP (Internet Control Message Protocol for IPv6) neighbor solicitation (NS) message to the previous access router and waits for an ICMP NA (Neighbor Advertisement) message from the previous access router. Since the mobile terminal has connected to the new access router, the previous access router does not respond to this. Therefore, if the ICMP NA message is not received for a predetermined time, the mobile terminal determines in step 205 that it has connected to the new access router. (NUD; Neighbor Unreachability Detection)

In steps 207 to 209, the mobile terminal first checks whether its own link-specific address is unique in the access router link to form an IPv6 address for use in the new access router. That is, the mobile terminal multicasts ICMP NS to other terminals and routers on the link using its link-limited address as a source address and receives and inspects an ICMP NA message in response to the same link as its link-limited address. Check if there is a host using a qualified address. (DAD; Duplicate Address Detection)                     

If the uniqueness of the link specific address is confirmed, in step 211 to step 213, the mobile terminal obtains the interface identifier and the prefix value of the access router to form an IPv6 address for use in the new link. Since the interface identifier is unique to the mobile terminal, it is already determined by the interface identifier negotiation in the PPP link establishment procedure with the PDSN. In step 211, the mobile terminal sends an ICMP Router Solicitation (ICMP RS) message for requesting a prefix value to the access router, and the access router to which the mobile terminal is connected returns an ICMP RA message including the prefix value. . In step 213, the mobile terminal acquires the prefix value.

In step 215, the mobile terminal combines the prefix value obtained from the access router with the interface identifier value to form a new IPv6 address. The IPv6 address is used as a CoA when the mobile terminal sends and receives packets on the link of the new access router.

In step 217, the mobile terminal transmits a binding update message including the CoA to the home agent in order to register the CoA with the home agent. The home agent binds and stores the CoA with the home address of the mobile terminal. After that, the packet transmitted to the mobile terminal is delivered to the new CoA through the home agent.

In step 219, the mobile terminal also transmits a binding update message including the CoA to the counterpart node in order to register the CoA to the counterpart node with which it was previously communicating. Thereafter, when the partner node transmits a packet to the mobile terminal using route optimization, the partner node immediately transmits the packet to the new CoA.

4 is a message flow diagram illustrating a procedure for forming an IP address on a PPP link by a mobile terminal using MIPv6 according to the procedure of FIG. 3. Here, an embodiment in which a mobile terminal accesses a PDSN using a PPP connection and receives a wireless Internet service from a CDMA2000 system is shown.

In step 301, the mobile terminal moves from the previous PDSN to which it is connected, and accesses the new PDSN. Since there is no two-layer link between the mobile terminal and the PDSN, in steps 303 to 305, when it is confirmed that the mobile terminal accesses the PDSN, LCP messages are exchanged between the mobile terminal and the PDSN to form a link for communication between both ends. do. This corresponds to the "Establish" phase of the PPP operating state.

When the link of the PPP connection is established, the mobile terminal enters the "Network" step in step 307 to form the interface identifier of the mobile terminal, and transmits the interface identifier value in the link control protocol message to the PDSN. In step 309, the PDSN and the mobile station determine an interface identifier of the mobile terminal through an interface identifier negotiation defined in RFC 2472.

In step 311, the mobile station forms a link-limited IPv6 address using the determined interface identifier value and the well-known link-local prefix FE80 :: 0. As defined in RFC 2472, duplicate check DAD of link addresses is omitted.

In step 313, the mobile station transmits an ICMP RS message for requesting a prefix value to the PDSN for address formation, and in step 315 receives an ICMP RA message including the prefix value from the PDSN to which the mobile terminal is connected. In step 317, the mobile terminal combines the prefix value with the interface identifier value to form a new CoA.

In step 317, the mobile terminal transmits a binding update message including the CoA to the home agent in order to register the CoA to the home agent node, and the home agent binds and stores the CoA with the home address of the mobile terminal. After that, the packet transmitted to the mobile terminal is delivered to the new CoA through the home agent. In step 319, the mobile terminal transmits a binding update message including the CoA to the counterpart node in order to register the CoA to the counterpart node, and the counterpart node transmits the packet using the path optimization to the mobile station. Use

The mobile terminal uses an IPv6 CP configuration option when performing interface identifier negotiation with the PDSN. As proposed in RFC 2472, configuration options are classified into type 1 and type 2, type 1 means an interface identifier, and type 2 means an IP compression protocol (IP-Compression-Protocol). The present invention uses an additional IPv6 control protocol configuration option type 3 for providing the mobile terminal with the prefix of the PDSN via the link control protocol. The message format of the IPv6CP configuration option according to the type 3 is illustrated in FIG. 5.

Referring to FIG. 5, a message of type 3 IPv6CP configuration option is composed of a type field of 1 byte, a length field of 1 byte, a subtype field of 1 byte, and a value field of 8 bytes. The type field is three. The length field indicates the length, in bytes, of a configuration option of type 3, which here is 12. The subtype field has a value of 1 or 2. Subtype = 1 means that the configuration option is used when assigning an interface identifier, and subtype = 2 means that the configuration option is used when assigning a prefix. The value field is the data value that the configuration option wants to convey. When subtype = 1, the value field contains an interface identifier value assigned by the PDSN to the mobile terminal, and when subtype = 2, the value field contains the prefix value of the PDSN.

In the present invention, by using the IPv6CP configuration option as described above, the interface identifier of the PDSN is fixed to the default value without setting both interface identifiers in the interface identifier negotiation process.

6A to 6C compare the operations when using each setting option. 6A and 6B show a case of using a setting option (type 1) for negotiating an interface identifier, and FIG. 6C shows a case of using a setting option (type 2) for using a fixed interface identifier. will be.

Referring to FIG. 6A, in step 501, both the mobile terminal and the PDSN select ID0 as the basic interface identifier, and deliver the selected ID0 in a Configure-Request message to each other. In step 503, the mobile station notifies the configuration-Nak message to change to ID2 since the PDSN selects the same interface identifier. The PDSN likewise carries ID1 in a Configure-Nak message.

In step 505, the mobile terminal and the PDSN transmit their changed interface identifiers ID1 and ID2 in the setup-request message, respectively. In step 507, the mobile station and the PDSN transmit a Configure-Ack message to the other party, indicating that the interface identifier negotiation process is successful because the value of the newly transmitted interface identifier from the other party is different from its current interface identifier. Finally, in step 509, the mobile terminal uses ID1 and the PDSN uses ID2 as the interface identifier.

FIG. 6B illustrates an operation of finally setting different interface identifiers when the mobile terminal and the PDSN initially select the same basic interface identifier and are set to the same interface identifier even after the first negotiation.

Referring to FIG. 6B, in step 511, both the mobile terminal and the PDSN select ID0 as the basic interface identifier, and deliver the selected ID0 in a Configure-Request message to each other. In step 513, the mobile station notifies the configuration-Nak message that the PDSN selects the same interface identifier as its own and replaces it with a new interface identifier ID1. At this time, the PDSN selects ID1 by the same selection algorithm as that of the UE, and delivers the PDSN in a Configure-Nak message.

In step 515, the mobile terminal transfers the new interface identifier ID1 to the setup-request message to the PDSN. At this time, the PDSN also delivers a new interface identifier ID1 to the mobile terminal. The mobile terminal then recognizes that the interface identifier has collided again and informs the PDSN of another new interface identifier ID3 in the setup-nak message in step 517. The PDSN will also pass the new interface identifier ID2 via the setup-nak message. In step 519, the mobile terminal and the PDSN deliver the second proposed interface identifiers ID2 and ID3 to each other through a setup-request message. In step 521, the mobile terminal and the PDSN confirm that the interface identifier transmitted by the mobile station and the interface identifier received from the counterpart are different from each other, and transmit a Configure-Ack message to the other party to inform that the interface identifier negotiation process is successful. Finally, in step 521, the mobile terminal determines that ID2 is used and the PDSN uses ID3 as the interface identifier.

As shown in Fig. 6B, the time for full negotiation increases whenever the interface identifiers at both ends overlap. The probability of duplicate interface identifiers at both ends decreases as the number of duplicates increases.

6C illustrates an operation of changing and setting an interface identifier of a mobile terminal by the PDSN when the mobile terminal and the PDSN initially select the same basic interface identifier according to the present invention.

Referring to FIG. 6C, in step 525, both the mobile terminal and the PDSN select ID0 as the basic interface identifier, and deliver the selected ID0 in a setup-request message to each other. In step 527, since the PDSN selects the same interface identifier as the mobile station, the PDSN notifies to ID1 that it changes to ID1.

In step 529, the mobile terminal sends a setup-acknowledgement message to the setup-request message of the PDSN. In step 531, the PDSN determines ID0 as an interface identifier in response to the setup-acknowledgement message. In step 533, the mobile terminal transfers the changed interface identifier ID1 to the PDSN in the setup-request message. In step 535, the PDSN returns a setup-acknowledge message because the mobile terminal has selected a different interface identifier from the mobile station. At this time, the PDSN transmits its prefix value together with the configuration-acknowledgement message so that the mobile station can form an IPv6 address.

In step 537, the mobile station receives the configuration-acknowledgement message from the PDSN and confirms that ID1 can be used as the interface identifier. At the same time, the mobile terminal acquires the prefix value required for IPv6 address formation.

As described above, the PDSN remains fixed without changing the basic interface identifier initially selected after the PPP connection. When an IPv6 control protocol including a configuration option of type = 3 is received from the mobile terminal, the PDSN operates as follows.

If the interface identifier value of the configuration-request message received from the mobile terminal is the same as the interface identifier value of the configuration-request message which was recently transmitted by the mobile terminal, the other interface value is selected and delivered to the mobile terminal in the configuration-nake message. .

If the interface identifier value of the configuration-request message received from the mobile terminal is different from the interface identifier value of the configuration-request message that was recently transmitted, the prefix value is transmitted to the mobile terminal with the configuration option of the configuration-acre message. do.

When the setup-acknowledgement message is received from the mobile terminal, the interface identifier value of the setup-requirement message which is most recently delivered by the mobile station is selected as the interface identifier to be used later.

When the setup-nak message is received from the mobile terminal, the interface identifier, which has been most recently transmitted, is delivered to the mobile terminal in the setup-request message.                     

7 is a state transition diagram showing a setting option processing operation of a PDSN according to a preferred embodiment of the present invention.

In state 601, when the link of the PPP connection is opened and enters the "Network" phase, the PDSN sends a setup-request message according to the PPP link control protocol. In this case, an IPv6CP message including a type = 3 and a subtype = 1 and a basic interface identifier value of the PDSN is included.

In state 603, the PDSN waits for the establishment-request message of the mobile terminal to be delivered. If the interface identifier value of the mobile terminal included in the mobile terminal's configuration-request message in state 605 is the same as that of the PDSN, the PDSN generates a new interface identifier value and generates a configuration-nak message including the new interface identifier value. Deliver to mobile terminal.

If the interface identifier value of the mobile terminal included in the configuration-request message of the mobile terminal is different from that of the PDSN in state 607, the PDSN transmits its prefix value to the mobile terminal through the configuration-acknowledgement message.

If a setup-acknowledge message has been received from the mobile terminal and a setup-acknowledgement message has also been sent to the mobile terminal, the interface negotiation operation at the PDSN ends at state 609.

In the present invention, the mobile terminal does not change the PDSN's interface identifier even if its interface identifier and the PDSN's interface identifier are the same. Therefore, when receiving the IPv6 control protocol including the configuration option of type = 3 from the PDSN, the mobile terminal operates as follows.

Upon receipt of the setup-request message from the PDSN, the setup-acknowledge message is delivered to the counterpart regardless of the interface identifier value.

Upon receiving the setup-nak message from the PDSN, it changes its interface identifier to the value contained in the setup-nak message, and re-delivers the changed value to the PDSN with the setup-request message.

Upon receipt of the setup-acknowledgement message from the PDSN, the interface identifier value of the most recently delivered setup-request message is determined as the interface identifier to be used later, and the value contained in the setup-acre message's value field is used as a prefix.

8 is a state transition diagram showing a setting option processing operation of a mobile terminal according to an embodiment of the present invention.

In state 701, when the link of the PPP connection is opened and enters the "Network" phase, the mobile terminal sends a setup-request message according to the PPP link control protocol. In this case, an IPv6CP message including type = 3 and subtype = 1 and having a default interface identifier value of the mobile station is included.

In state 703 the mobile terminal waits for an acknowledgment from the PDSN. If the setup-nak message is delivered from the PDSN in state 705, the mobile terminal changes its interface identifier to the value contained in the setup-nak message. The mobile terminal resends the setup-request message including the changed interface identifier value to the PDSN.                     

If a setup-arc message is received from the PDSN in state 707, the mobile terminal sets its prefix to the value contained in the setup-acre message. In state 709, if a setup-request message is received from the PDSN during the interface identifier negotiation process, the mobile station transmits a setup-acre message.

If a setup-acknowledgement message has been sent to the PDSN and a setup-acknowledgement message has also been received from the PDSN, the interface negotiation operation at the mobile terminal ends at state 711.

9 illustrates an address forming operation according to a preferred embodiment of the present invention. Here, an embodiment in which the mobile terminal uses a type 3 IPv6CP configuration option is shown. As shown, the procedure of FIG. 9 according to the preferred embodiment of the present invention forms a new IPv6 address quickly and simply compared to the embodiment of FIG. 4 described above.

Referring to FIG. 9, in step 801, the mobile terminal moves from the previous PDSN to which it is connected, and accesses the new PDSN. After confirming that the mobile terminal accesses the PDSN in step 803, the mobile station exchanges LCP messages with the PDSN. In step 805, a link for communication between both ends is formed. When the link of the PPP connection is established, in step 807, the mobile station exchanges LCP messages by the procedure of FIG. 6c mentioned above to determine the interface identifier value and obtain the prefix value of the PDSN. In step 809, the mobile terminal forms CoA using the determined interface identifier value and the prefix value.

In step 811, the mobile terminal transmits a binding update message including the CoA to the home agent to register the CoA with the home agent node, and the home agent binds and stores the CoA with the home address of the mobile terminal. After that, the packet transmitted to the mobile terminal is delivered to the new CoA through the home agent. In step 813, the mobile terminal transmits a binding update message including the CoA to the counterpart node to register the CoA with the counterpart node, and the counterpart node transmits the packet using the path optimization to the mobile station. Use

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but is capable of various modifications within the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the scope of the following claims, but also by those equivalent to the scope of the claims.

In the present invention operating as described in detail above, the effects obtained by the representative ones of the disclosed inventions will be briefly described as follows.

The present invention minimizes the loss of IP packets by reducing the delay that occurs when a MIPv6 mobile terminal forms an IPv6 CoA over a PPP connection. In other words, it is possible to form an IPv6 address quickly and simply by reducing the delay required to determine an interface identifier value or to obtain a prefix value required to form a new CoA.

Claims (9)

A method of forming an Internet address of a mobile terminal for receiving a wireless Internet service in a mobile communication system in which the mobile terminal accesses the Internet by packet data service nodes, A mobile terminal newly accessing a packet data service node, and transmitting a basic interface identifier identifying the link to the packet data service node to form a link with the accessed packet data service node; If a setup-nak message is received from the packet data service node requesting to change the basic interface identifier, sending a setup-request message to the packet data service node including a new interface identifier in response to the setup-nak message. Process, Combining a new interface identifier with the prefix value upon receiving a setup-arc message containing the prefix value of the packet data service node from the packet data service node in response to the setup-request message comprising the new interface identifier. Forming a new internet address of the mobile terminal. The packet data service of claim 1, wherein when a configuration-request message is received from the packet data service node, the configuration-arc message is transmitted regardless of an interface identifier value included in the configuration-request message received from the packet data service node. Internet address formation method characterized in that the transmission to the node. 2. The method of claim 1, wherein the setup-nak message includes an interface identifier value and the new interface identifier is set to an interface identifier value included in the setup-nak message. The method of claim 1, wherein when a setup-acknowledge message is received from the packet data service node, a new interface identifier value included in the setup-request message is determined as an interface identifier to be used later. The method of claim 1, wherein the mobile terminal uses a configuration option of Mobile Internet Protocol version 6. A method of providing a wireless Internet service to a mobile terminal by a packet data service node in a mobile communication system in which the mobile terminal connects to the Internet by a packet data service node, Transmitting a basic interface identifier identifying the link to the mobile terminal to form a link with a mobile terminal that has newly accessed a packet data service node; When the setup-request message including the interface identifier of the mobile terminal is received from the mobile terminal, comparing the interface identifier of the mobile terminal with the basic interface identifier; If the interface identifier of the mobile terminal is the same as the basic interface identifier, transmitting a setup-nak message including the new interface identifier selected for the mobile terminal to the mobile terminal; If the interface identifier of the mobile terminal is not the same as the basic interface identifier, transmitting a setup-acknowledge message including a prefix value of the packet data service node to the mobile terminal; And receiving the configuration-acknowledgement message from the mobile terminal, determining the default interface identifier value as an interface identifier to be used later, and ending the interface negotiation. The method of claim 6, wherein when receiving a setup-acknowledgement message from the mobile terminal, the interface identifier value included in the most recently transmitted setup-request message is determined as an interface identifier to be used later. . The method of claim 6, wherein, upon receiving a setup-nake message from the mobile terminal, the most recently transmitted interface identifier is included in a setup-request message and transmitted to the mobile terminal. 8. The method of claim 7, wherein the mobile terminal uses a configuration option of Mobile Internet Protocol version 6.

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