KR100589681B1 - Hierarchical Mobile IP System capable of IP Packet Transmission and IP Packet Transmission Method in the System - Google Patents

Abstract

The present invention relates to a hierarchical mobile IP system capable of efficient IP packet transmission and an IP packet transmission method in the system.

A hierarchical mobile IP system for transmitting an IP (Internet Protocol) packet of a mobile terminal of the present invention includes a home agent (HA) for managing a mobile terminal and controlling IP packets of an internal network and an external network; OAM server (Server) that performs the role of configuration management and operational integrity of the domain network; And a PAR that controls the mobile terminal and performs a foriegn agent (FA) function, and determines whether to reverse tunnel the IP packet based on whether the destination address of the IP packet received from the mobile terminal is within a specified domain reverse tunneling table. Include.

According to the present invention, when the mobile terminal is in the home domain by using the network shape in the domain in the external agent (HA), reverse tunneling is provided only for an IP packet destined for the IP address of the mobile terminal in the same domain. By transmitting to the HA in the domain, it is to provide fast communication between mobile terminal devices while handling user traffic more effectively in a hierarchical mobile IP network.

Hierarchical Mobile IP System, OAM Server, PAR, IP Packet

Description

Hierarchical Mobile IP Packet System for efficiently transmitting IP Packet and IP Packet Transmission method

1 is a block diagram illustrating a user packet flow when general reverse tunneling is performed in a mobile communication network according to the related art.

2 is a block diagram showing the structure of a hierarchical mobile IP packet system capable of efficient IP packet transmission according to an embodiment of the present invention.

3 is a block diagram illustrating a user packet flow when efficient reverse tunneling is performed in a hierarchical mobile IP packet system capable of efficient IP packet transmission according to an embodiment of the present invention.

4 is a flowchart illustrating a hierarchical mobile IP system capable of efficient IP packet transmission and an IP packet related to control messages and reverse tunneling in the system according to an embodiment of the present invention.

5 is a signal flow diagram of an IP packet in a hierarchical mobile IP system capable of efficient IP packet transmission according to an embodiment of the present invention.

The present invention relates to a hierarchical Mobile Internet Protocol (IP) system capable of efficient IP packet transmission and a method for transmitting an IP packet in the system. The present invention relates to a packet access router (PAR) in a hierarchical mobile IP. The present invention relates to an apparatus and method for providing reverse tunneling for an IP (Internet Protocol) destination packet having an IP address as in a home domain.

Mobile IP has been proposed in order to provide IP mobility for a mobile terminal device accessing an Internet network in a mobile communication network.

Republic of Korea Patent Publication No. 10-2002-0068419 "A device and method for providing a mobile IP function of a wireless LAN system and a data transmission method of a node using a mobile IP function" is the AP (Access) Point (hereinafter referred to as AP) describes a technology for providing a mobile IP function.

In general mobile IP, the functions of a home agent (hereinafter referred to as HA) and an external agent (hereinafter referred to as FA) are defined as being simultaneously accepted by one router or present on the same link (subnet). However, in the mobile communication system structure, HA functions as a router that performs location management for mobile subscribers and tunneling of user data. Because of the function of such a router, the structure of the mobile communication system is convenient for management and external attack. A centralized network is adopted to protect against the risks of

In mobile communication networks such as 3GPP, 3GPP2 and portable Internet systems, HA is concentrated and FA is composed of hierarchical mobile IP networks.

In this hierarchical mobile IP network, a mobile terminal device may request communication with not only a host in the external Internet but also with other mobile terminal devices in the internal network. The tunneling method is used.

However, due to the hierarchical mobile IP structure, mobile terminal devices belonging to the same domain always require reverse tunneling when registering mobile IP, and all IP packets transmitted and received with the mobile terminal device always pass through the HA of the mobile terminal.

1 is a block diagram showing a user packet flow when performing normal reverse tunneling in a mobile IP network according to the prior art, wherein a solid solid arrow indicates a general IP packet section and a thick solid arrow indicates a tunneled IP packet section do.

P1 is directed from AT1-1 (10) to AT1-2 (11) when AT1-1 (10) in the home domain (mobile communication domain 1) communicates with AT1-2 (11) homed in the same domain. Shows the flow of IP packets. It is assumed that AT1-1 (10) and AT1-2 (11) are in the home subnet. First, the IP packet transmitted from the AT1-1 10 is received by the AP 20, encapsulated in the PAR1 30, and transmitted to the HA1 40 through the router 30. An IP packet transmitted from an AT (hereinafter referred to as an AT) is encapsulated unconditionally without searching a routing table in the PAR1 30, and the encapsulated IP packet transmitted through the AT may be passed through a general router according to a network structure. Next, HA1 40 decapsulates the encapsulated packet into a general IP packet, searches the visitor table, recognizes that AT1-2 (11) is in PAR2 (31), and has AT1-2 (11). The general IP packet is transmitted to the PAR2 31 through the general IP routing.

On the other hand, P2 indicates an IP packet flow when AT2-1 12 having mobile communication domain 2 as its home domain communicates with external host 60 after handing off to mobile communication domain 1. The IP packet sent from the AT2-1 (12) is encapsulated in the PAR2 (31) and passed through the internal router 70, followed by the HA2 (41) via the external ISP1 (50), the external ISP2 (51) and the external ISP3 (52). Is sent to. Next, in HA2 41, the encapsulated IP packet is decapsulated to make a general IP packet, and then the visitor table is searched, and the destination of the IP packet is not present in the visitor table, and thus is transmitted to the external host 60 using general IP routing. .

In this method, since all IP packets transmitted and received to and from a mobile terminal device in a mobile IP network having a hierarchical structure must always pass through the HA of the mobile terminal device, IP routing becomes inefficient and unnecessary IP is required for the mobile communication network and the Internet network. Increase traffic In addition, all users should perform reverse tunneling on IP packets, which increases the load of encapsulation and reverse encapsulation in FA and HA.

Accordingly, in order to solve the above problem, the present invention provides a mobile terminal apparatus using a network shape in a domain of an OAM (Operations, Administration and Maintenance) server in a hierarchical mobile IP network capable of efficient IP packet transmission. Reverse tunneling is provided only for IP packets destined for the IP address of the mobile terminal device in the domain, such as when it is in a domain, and transmitted to the HA in the domain, thereby handling user traffic more effectively in a hierarchical mobile IP network. A hierarchical mobile IP system providing direct communication between devices and an IP packet transmission method in the system are provided.

In order to solve the above technical problem, a hierarchical mobile IP system for transmitting an IP (Internet Protocol) packet of a mobile terminal according to the first aspect of the present invention,

A home agent (HA) for managing mobile terminals and controlling IP packets of internal and external networks; OAM server (Server) that performs the role of configuration management and operational integrity of the domain network; And control the mobile terminal and perform a Foriegn Agent (FA) function, and whether the destination address of the IP packet received from the mobile terminal is within the specified domain reverse tunneling table-generated based on the information of the domain network received from the OAM server- It includes a PAR for determining whether to reverse tunnel the IP packet based on whether or not.

Here, when the destination address of the IP packet is not in the specified domain inverse table, the PAR is transmitted to the destination address without performing reverse tunneling.

In addition, the domain reverse tunneling table is generated by the information of the domain network received from the OAM server at the time of initialization of the PAR, characterized in that is updated by the OAM server whenever the information of the domain network is updated.

 According to a second aspect of the present invention, a method for transmitting an IP packet by a PAR managing a mobile terminal in a hierarchical mobile IP system,

 a) receiving an IP packet from a mobile terminal; b) determining whether to reverse tunnel based on whether the destination address of the IP packet is within a specified domain reverse tunneling table; And c) if the destination address of the IP packet is not in the specified domain reverse tunneling table, transmitting to the destination address without reverse tunneling for the IP packet.

Hereinafter, a hierarchical mobile IP system capable of efficient IP packet transmission and an IP packet transmission method in the system will be described in detail with reference to the accompanying drawings.

2 is a block diagram showing the structure of a hierarchical mobile IP packet system capable of efficient IP packet transmission according to an embodiment of the present invention.

Referring to FIG. 2, a hierarchical mobile IP packet system capable of efficient IP packet transmission includes an HA 400, an OAM Server 500, a Packet Access Router (PAR) 300, and an AP. It includes an AP 200, AT (Access Terminal; referred to as AT) (100).

The HA 400 provides a management function for mobile terminals and a tunneling function for user data, and selectively decapsulates the encapsulated IP packet transmitted from the PAR 300.

The OAM Server 500 manages the shape of each network in real time, stores information on subnets existing in the mobile communication domains, and plays a role of network shape management and operation maintenance.

 The PAR 300 is a device that controls the APs 200 and performs a FA function. The PAR 300 receives a network shape from the OAM server 500, stores information on subnets existing in the mobile communication domain, and stores a destination of an IP packet. Generates a list of domain reverse tunneling tables used to check addresses and perform encapsulation on registered lists. After retrieving the destination address of the IP packet of the AP 100 received from the AT 200 in the stored domain reverse tunneling table, if the destination address belongs to the home domain, it is encapsulated and transmitted to the HA 400, and the destination address is transferred to the home domain. If it does not belong, it does not perform encapsulation and sends it to the router.

In addition, the PAR 300 generates a mobile IP reverse tunneling table that manages a list of mobile terminal devices that require reverse tunneling when registering a mobile IP location and generates a visitor table that manages information about the address of the visitor IP.

The FA function refers to a router function in which the AT 100 is connected to a wireless mobile communication network connected to each other wirelessly and is in charge of data transmission to the AT 100 in cooperation with the HA 400.

The AP 200 receives the IP packet transmitted from the AT 100 and transmits it to the PAR 300 by wire and controls the AT 100 in a wireless section.

The AT 100 is a mobile terminal device equipped with a multimedia service application such as a laptop equipped with a wireless LAN card, a personal digital assistant (PDA), or a mobile phone Internet access device. A device that provides a mobile terminal function.

The router 600 generally controls the connection flow between the mobile communication domain and the external ISP, and may be replaced by the HA 400.

3 is a block diagram illustrating a user packet flow when efficient reverse tunneling is performed in a hierarchical mobile IP packet system capable of efficient IP packet transmission according to an embodiment of the present invention.

Referring to FIG. 3, a thin solid line arrow indicates a general IP packet section and a thick solid line arrow indicates a tunneled IP packet section. P3 represents the flow of IP packets from AT1-1 (100) to AT1-2 (110) when AT1-1 (100) in the home domain communicates with AT1-2 (110) that homes the same domain. . It is assumed that AT1-1 100 and AT1-2 110 are in the home subnet.

The PAR1 300 and the PAR2 310 receive a network shape at the time of initialization from the OAM server 500 and store information on subnets existing in the mobile communication domain 1.

The IP packet transmitted from the AT1-1 (100) is wirelessly received by the AP 200 and transmitted from the AP 200 to the PAR1 300 by wire. PAR1 (300) retrieves the destination address of the IP packet and if the destination address belongs to the home domain encapsulation and transmits to the HA1 (400). At this time, the encapsulated IP packet transmitted may be via the router 600 according to the network structure. HA1 (400) decapsulates the encapsulated IP packet into a general IP packet, then searches the visitor table, recognizes that there is AT1-2 (110) in PAR2 (310), and then PAR2 with AT1-2 (110). In step 310, the general IP packet is transmitted through the general IP routing.

P4 represents an IP packet flow when the AT2-1 120 having the mobile communication domain 2 as the home domain communicates with the external host 800 after handing off to the mobile communication domain 1. The IP packet sent from the AT2-1 120 searches for the destination address of the corresponding IP packet in the PAR2 310 and thus performs general IP routing because the destination address does not belong to the home domain. After passing through the router, the IP packet is transmitted to the external host 800 via the external ISP1 700.

4 is a flowchart illustrating processing of an IP packet related to control messages and reverse tunneling in a hierarchical mobile IP system capable of efficient IP packet transmission according to an embodiment of the present invention.

Referring to FIG. 4, when the PAR1 300 and the PAR2 310 are driven, shape information about the subnet in the network is received from the OAM server 500 in the domain (S100) and a list of domain reverse tunneling tables is generated (S100). S110).

The PAR1 300 and PAR2 310 receive the changed information from the OAM server 500 whenever the network shape is changed, and change the list of the domain reverse tunneling table based on the received information to change the shape of the network in real time. Save the information.

Hereinafter, the PAR1 300 will be described as an example.

The PAR1 300 receives the IP packet from the AP 200 (S130) and checks whether it is a mobile terminal device that has requested reverse tunneling at the time of mobile IP registration (S140).

The mobile terminal device checking for reverse tunneling when the mobile IP is registered is performed by checking whether the source address of the corresponding IP is the terminal device address registered in the mobile IP reverse tunneling table.

If the terminal device is registered in the mobile IP reverse tunneling table, after performing encapsulation of the HA1 400 as a destination using the reverse tunneling table list (S141), the terminal device transmits the information to the corresponding HA1 400 (S170).

In step S140, if it is not the mobile terminal device registered in the mobile IP reverse tunneling table, it is first checked whether the destination address of the IP packet is registered in the visitor table (S150). It forwards through the registered AP as it is without encapsulation (S170).

If the destination address of the IP packet is not present in the visitor table, it is checked whether it is in the domain reverse tunneling table (S160). ), And transmits to the HA in the home domain in which the destination address exists (S170).

However, if the destination address of the IP packet does not exist in the domain reverse tunneling table, the IP packet is forwarded using the routing table for the received packet without encapsulating the IP packet.

5 is a signal flow diagram of an IP packet in a hierarchical mobile IP system capable of efficient IP packet transmission according to an embodiment of the present invention.

Referring to FIG. 5, the AT2-1 120 is a terminal device hand-offed from another mobile communication domain network to a hierarchical mobile IP network. The AT2-1 120 generates an PAR2 310 by generating an IP packet to access the external host 800. (S200).

The PAR2 310 receives and stores network shape information about subnets in the network from the OAM server 500, and transmits an IP packet based on the list of the domain reverse tunneling table generated based on this (S220). At this time, the AT1-2 120 does not require the mobile IP reverse tunneling, and since the external host 800 that is the communication target is also not included in the domain reverse tunneling table and the visitor table, the AT1-2 120 transmits the IP packet without performing encapsulation.

The router 600 receives the IP packet and transmits it to the external ISP 500 (S230). The transmitted IP packet is transmitted from the external ISP 500 to the external host 800 of another mobile communication domain network.

On the other hand, AT1-1 (100) is a mobile terminal device to establish a connection with the AT1-2 (110) in the hierarchical mobile IP network, and generates an IP packet to access the AT1-2 (110) PAR1 (300) (S240).

Similarly, the PAR1 300 receives and stores shape information about subnets in a network from the OAM server 500, and generates and stores a list of domain reverse tunneling tables based on the shape information. At this time, since the destination address of the AT1-2 (110) is in the domain reverse tunneling table, the PAR1 (300) encapsulates the IP packet and transmits it to the router 600 (S260).

The router 600 receives the encapsulated IP packet and transmits it to the home agent 400 (S270). The home agent 400 decapsulates the encapsulated IP packet into a general IP packet, searches the visitor table, and then retrieves the PAR2 (310). After recognizing AT1-2 (110) belonging to the AT1-2 (110) and transmits the IP packet to the PAR2 (310) with the general IP routing (S280).

The PAR2 310 searches for a corresponding destination of the IP packet in the visitor table, and transmits the IP packet to the searched corresponding terminal device AT1-2 110 (S300).

Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited thereto, and various other changes and modifications are possible.

According to the present invention, when a mobile terminal device is in a home domain by using a subnet network shape in a domain, reverse tunneling is provided only for an IP packet destined for an IP address of a mobile terminal device belonging to the same domain. By providing a high speed network, the user's traffic is handled more efficiently in a hierarchical mobile IP network, and thus, a fast communication is provided between mobile terminal devices.

Claims (11)

In the hierarchical mobile IP system for transmitting an IP (Internet Protocol) packet of the mobile terminal, OAM server (Server) that performs the role of configuration management and operational integrity of the domain network; And A domain reverse tunneling table for controlling the mobile terminal and performing a Foriegn Agent (FA) function, and specifying a destination address of an IP packet received from the mobile terminal, wherein the domain reverse tunneling table is a domain reverse tunneling table of the domain network received from the OAM server. Created based on information—a PAR that determines whether to reverse tunnel the IP packet based on whether it is within Hierarchical mobile IP system comprising a. The method of claim 1, And when the destination address of the IP packet is not within the specified domain reverse table, the PAR transfers the address to the destination address without performing reverse tunneling. The method of claim 2, The domain reverse tunneling table is generated as information on a domain network received from the OAM server at the time of initialization of the PAR, and is updated by the OAM server whenever domain information is updated. system. The method of claim 1, The PAR is a hierarchical mobile IP system including a mobile IP reverse tunneling table for managing a list of mobile terminals that required reverse tunneling when registering mobile IP. In claim 4, The mobile terminal further includes a home agent (HA) for controlling IP packets of an internal network and an external network, The PAR is a hierarchical mobile IP system, if the mobile station that has transmitted the IP packet is included in the list of the mobile IP reverse tunneling table to perform reverse tunneling on the IP packet to deliver to the HA. In a method for transmitting an IP packet by a PAR managing a mobile terminal in a hierarchical mobile IP system, a) receiving an IP packet from the mobile terminal; b) Reverse tunneling based on whether or not the destination address of the IP packet is within the domain reverse tunneling table, where the domain reverse tunneling table is generated based on the information of the OAM server, which is responsible for configuration management and operational integrity of the domain network. Determining; And c) if the destination address of the IP packet is not in the specified domain reverse tunneling table, transmitting to the destination address without reverse tunneling for the IP packet Hierarchical mobile IP packet transmission method comprising a. The method of claim 6, Step b), If the destination address of the IP packet is in the domain reverse tunneling table, performing the reverse tunneling on the IP packet and transmitting the reverse packet to the home agent (HA) of the mobile terminal Hierarchical mobile IP packet transmission method further comprising. The method according to claim 6 or 7, The PAR includes a mobile IP reverse tunneling table that manages a list of mobile terminals that request reverse tunneling when registering mobile IP. Between steps a) and b), Determining whether the mobile terminal that has transmitted the IP packet is in the mobile IP reverse tunneling table list; And If the mobile station is in the mobile IP reverse tunneling table list, performing reverse tunneling on the IP packet and transmitting the reverse packet to the HA of the mobile station; Hierarchical mobile IP packet transmission method further comprising. The method of claim 8, The PAR further includes a visitor table for managing information about the address of the visitor IP, If the mobile terminal is not in the mobile IP reverse tunneling table list, determining whether a destination address of the IP packet is in the visitor table; If the destination address of the IP packet is in the visitor table, transmitting to the destination address of the IP packet without reverse tunneling the IP packet; And If the destination address of the IP packet is not in the visitor table, performing step b) Hierarchical mobile IP packet transmission method further comprising. The method of claim 6, Before step a), Receiving network shape information from the OAM server; And Generating the domain reverse tunneling table based on the received network formation information Hierarchical mobile IP packet transmission method comprising a. The method of claim 10, Updating the domain reverse tunneling table through the OAM server whenever the information of the domain network is updated; Hierarchical mobile IP packet transmission method further comprising.

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