KR100926654B1 - A method of routing data packets in a mobile internet system and an access routing agent using the same - Google Patents

Abstract

Disclosed is a routing method of a mobile internet system that can solve a problem of a bypass path and improve security of location information. In the mobile Internet system, each of the mobile terminals corresponds to an access routing agent, and the access routing agents are configured to transmit and receive IP packets on behalf of the mobile terminals. At this time, each of the mobile terminals are identified through a unique IP address, and the location of the current mobile terminals is identified by the address of the access routing agent to which the mobile terminals are connected. In addition, the IP packet transmitted between the terminals is configured to be encapsulated by the access routing agent to be transferred between the access routing agents. By doing so, the problem of bypass routing and the complicated procedures for maintaining and managing tunneling are eliminated, and since the complex processing procedures related to routing are handled at the agent level, each terminal has the location information of the other party. There is no need to learn, so it can have high security for location information.

Mobile Internet, Routing, Agents, Routers

Description

TECHNICAL FIELD OF DATA PACKET ROUTING IN MOBILE INTERNET SYSTEM AND ACCESS ROUTING AGENT USING THE SAME

The present invention relates to a routing method of a mobile internet system and a configuration of an agent for realizing the same. A routing method and an access routing agent using the same.

Mobile IP (mobile internet protocol) technology is a technology for supporting the mobility (mobility) of the terminal connected to the Internet network. Many problems have to be solved in order to keep the terminal always connected to the Internet while moving. Fundamentally, the Internet is made up of several subnets connected through routers, and routers transmit packets based on network prefixes, so mobile nodes move from one subnet to another. It is difficult for MNs (Mobile Nodes) to stay connected to the Internet. That is, the mobile node must be assigned a new IP address in order to communicate on another subnet, but changing the IP address means disconnection in the transport layer, which is a higher layer of the IP protocol. Done. That is, in the conventional Internet technology, since the IP address is information that means not only the identification of the terminal but also the location of the terminal, the mobile terminal cannot deliver a packet to a changing location.

In this environment, as a mobile IP protocol for delivering packets sent to an existing IP address to a location where the terminal has moved, MIPv4 (Mobile Internet Protocol v4) and MIPv6 (Mobile Internet Protocol v6) are provided. The conventional method is to transmit a packet to the mobile terminal by creating a tunnel from the original position (home address), which means the IP address, to the newly moved position (temporary address). That is, all packets delivered to the mobile terminal are sent to a home agent (HA), which is registered with the mobile terminal, and then transmitted from the home agent to the mobile terminal through a tunnel. At this time, a tunnel is established between the home agent and the mobile terminal. In addition, each time the mobile terminal moves, the tunnel is updated from the original position to the newly moved position. Instead, all terminals simply use the existing IP protocol as it is and make a packet with a send / receive IP address and deliver it to the router.

However, whenever a mobile terminal changes its location, it must manage location registration and tunnel generation for delivering packets from the fixed IP location to the terminal at the current location. Since the mobile terminal is burdened to maintain its own home address and tunnel creation, a proxy mobile internet protocol (PMIP) that recently provides a protocol for supporting mobility at the network level instead of the terminal. Protocol technology has been devised. It is a mobility management protocol that handles tasks that need to be handled at the receiving end, such as mobile location registration and fixed IP location to current location, by proxy. The proxy component in the network takes care of this without the terminal having to establish a home address and tunnel to update the location or forward the packet.

However, the above-described schemes must deliver all packets destined for the mobile terminal to the pre-specified original location (home agent) regardless of the current location of the mobile terminal and the home agent is delivered to the terminal or proxy through tunneling to the mobile terminal. There is a limit to that. Therefore, there is a problem in that triangular routing occurs, in which a linear connection between a sender and a receiver is not always performed and a bypass is always made through a repeater.

In order to solve the above problems, a method for directly sending a packet to a moved terminal requires a method of identifying and sending the position of the moved terminal before the terminal sends the packet. In this way, a method using a dynamic domain name server (DNS) exists. In this method, the terminal finds the IP address currently located from the name of the receiver using the dynamic domain name server protocol. Similar to the existing cellular mobile communication, it receives the IP location information currently located from the recipient name and wraps the information with this IP location information before sending it. The receiving terminal releases the wrapped IP packet and extracts and processes the original packet. However, this method should register with the domain name server every time the terminal moves and notify the other terminal when there is a call so that it can change the connection settings. When the terminal moves, the change of location information should be recorded in the server and provided to the required terminal. In this case, the location information of the receiver is exposed to the terminal, which is vulnerable to security, and the inter-terminal compatibility may be a problem because the terminal should be responsible for all mobility management and processing.

An object of the present invention for solving the above problems, in the mobile Internet system, by using the access routing agent component that indirectly handles the problem of the Internet connection and routing of the mobile terminal, the bypass path through the home agent It is an object of the present invention to provide an agent based routing method of a mobile Internet system that can solve the problem of triangular routing and complicated procedures for maintaining a tunnel between a mobile terminal and a home agent.

Another object of the present invention for solving the above problems is, in the mobile Internet system, the problem of the triangular routing through the home agent and the complex procedure for maintaining the tunnel between the mobile terminal and the home agent The present invention provides an access routing agent that can indirectly address the problem of Internet access and routing of a mobile terminal.

The present invention for achieving the above object is, a mobile terminal to which the IP address is assigned, a home server that manages the routing of the subnet to which the mobile terminal belongs, a first access routing agent wirelessly connected to the mobile terminal, the mobile terminal A data packet routing method of a mobile internet system, comprising a source station for sending a data packet for the purpose of communication and a second access routing agent corresponding to the source station, the data packet sent by the source station for the purpose of the mobile terminal. A receiving step received by a second access routing agent, wherein the second access routing agent is configured to group an IP address of the mobile terminal or an IP address of the mobile terminal in a routing cache of the second access routing agent; Access Routing Agent Specific An inquiry step of inquiring an address for specifying the first access routing agent by an IP address grouping an IP address of the mobile terminal or an IP address of the mobile terminal through the home server, and the second access. A transmission step of transmitting the data packet to the first access routing agent without passing through the home server using an address specifying the first access routing agent queried by the routing agent and received by the first access routing agent It provides a routing method of a mobile Internet system comprising the step of delivering a data packet to the mobile terminal.

Here, the first access routing agent and the second access routing agent may have an address that uniquely specifies each, and the address specifying the first access routing agent and the second access routing agent may be an IP address. .

Herein, the first access routing agent and the second access routing agent have an address that uniquely specifies each, and the address specifying the first access routing agent and the second access routing agent is an Ethernet address. Can be.

Here, the first access routing agent and the second access routing agent have an address that uniquely specifies each, and the address specifying the first access routing agent and the second access routing agent may be a telephone number. have.

The routing cache of the second access routing agent may specify an access routing agent corresponding to an IP address of at least some IP addresses or at least some IP addresses grouped among mobile terminals existing in the mobile Internet system. It can be configured to associate and store addresses. In this case, in the querying step, when the IP address of the mobile terminal or the IP address of the IP address of the mobile terminal is grouped through the home server, the address specifying the first access routing agent is inquired. 1 may be configured to associate an IP address of the mobile terminal with an address specifying an access routing agent and to record it in the routing cache.

Herein, the data packet is an Internet protocol packet (IP packet), and the forwarding step includes specifying the first access routing agent inquired in the inquiry step to an IP packet sent by the originating station for the mobile terminal. It may be configured to deliver an encapsulized data packet by adding an addressed header. At this time, the first access routing agent, by using the packet decapsulated the encapsulated IP packet and the encapsulated data packet, to identify the IP address of the originating station and the address specifying the second access routing agent And associate the IP address of the originating station with the address specifying the second access routing agent and write it to the routing cache of the first access routing agent. At this time, when a data packet for the originating station is generated from the mobile terminal, in the routing cache of the first access routing agent, the second access routing agent to which the originating station is connected is identified using the IP address of the originating station. Query the address, and transmit the data packet to the second access routing agent without passing through the home server.

Here, the first access routing agent to identify the mobile terminal belonging to the coverage area, the IP address of the identified mobile terminal or the IP address of the identified mobile terminal grouped by the first access routing agent Recording the IP address of the identified mobile terminal or the IP address of the identified mobile terminal and recording the IP address of the identified mobile terminal and the first access routing agent. Associating a specified address, and writing to a binding database of the home server at a predetermined period and / or at the request of the first access writing agent, wherein the querying step is performed from the second access routing agent. Bar above with respect to By using a coding database query an address for identifying a first access routing agent it may be configured to transfer to the second access routing agent.

Here, the first access routing agent to identify the mobile terminal belonging to the coverage area and the IP address of the identified mobile terminal or the IP address of the identified mobile terminal group and the first access routing agent Associating an address specifying an address with the first access routing agent, and writing to a binding database of the home server at the request of the first access routing agent, wherein the querying step is performed in response to a request from the second access routing agent. It may be configured to look up an address specifying the first access routing agent using a binding database and forward it to the second access routing agent.

In this case, the binding database of the home server associates an IP address of at least some IP addresses or at least some IP addresses of mobile terminals existing in the mobile Internet system with an address specifying an access routing agent corresponding to each other. Can be configured to store.

Here, when the first access routing agent to which the mobile terminal is currently connected changes due to the movement of the mobile terminal, a new first access to a data packet for the mobile terminal received by the existing first access routing agent. It may be configured to forward through tunneling to the routing agent.

Here, when the first access routing agent to which the mobile terminal is currently connected changes due to the movement of the mobile terminal, an existing first access routing agent or a new first access routing agent is transferred from the originating station to the second access routing agent. Analyzing the data packet transmitted through the agent to identify the address specifying the second access routing agent, and the information corresponding to the new first access routing agent to the mobile terminal to the routing cache of the second access routing agent. It can be configured to request an update.

Here, when the first access routing agent to which the mobile terminal is currently connected changes due to the movement of the mobile terminal, the new first access routing agent receives information related to the mobile terminal from the routing cache of the existing first access routing agent. It can be configured to copy to the routing cache of.

Here, the first access routing agent to which the mobile terminal is currently connected may be configured to share information associated with the mobile terminal recorded in the routing cache with adjacent access routing agents.

One aspect of the present invention for achieving the above another object is a mobile terminal given an IP address, a home server that manages the routing of the subnet to which the mobile terminal belongs, a first access routing agent wirelessly connected to the mobile terminal A mobile Internet system comprising a calling station for sending a data packet for the mobile terminal and a second access routing agent corresponding to the calling station, wherein the second access routing agent is a mobile terminal existing in the mobile Internet system. A routing cache that records at least some IP addresses or at least some IP addresses grouped together with an address specifying a first access routing agent to which the mobile terminals are connected, and receives a data packet from an originating station. Data packet receiving unit Determines whether the destination packet of the data packet is a mobile terminal, and if the mobile terminal is a mobile terminal, inquires an address specifying a first access routing agent to which the mobile terminal is connected in the routing cache, or a subnet to which the mobile terminal belongs. The mobile station uses a control unit for querying an address specifying a first access routing agent to which the mobile terminal is connected through a home server that manages routing, and an address for specifying a first access routing agent to which the mobile terminal is currently connected. Provided is an access routing agent including a data packet sender for encapsulating a data packet for a terminal and delivering it to a first access routing agent currently connected to the mobile terminal without passing through the home server.

According to another aspect of the present invention for achieving the above object, an IP addressed mobile terminal, a home server managing routing of a subnet to which the mobile terminal belongs, a first access routing agent wirelessly connected to the mobile terminal A mobile Internet system comprising a source station for sending a data packet for the mobile terminal and a second access routing agent corresponding to the source station, wherein the first access routing agent is at least one mobile station within a coverage area. A mobile terminal discovery unit for identifying the terminal and receiving the identified IP addresses of the mobile terminals, a routing cache recording the identified IP addresses of the mobile terminals, a data packet receiver for receiving data packets from the outside, and a received data packet. Reverse encapsulation to recipient IP A data packet transmitter and a mobile terminal discovery unit which extracts an address and delivers the decapsulated data packet to the mobile terminal corresponding to the receiver IP address among the identified mobile terminals recorded in the routing cache. It provides an access routing agent, characterized in that it comprises a control unit for performing an operation for notifying the home server that manages the subnet to which the mobile terminal originally identified, the IP address of the mobile terminal and the address for identifying itself.

When using the routing method of the mobile Internet system according to the present invention as described above, in order to identify the mobile terminal, an IP address uniquely assigned to the mobile terminal is associated with an address specifying an access routing agent to which the mobile terminal is currently connected. By using it, it is possible to enable fast routing. That is, an IP address uniquely assigned to a mobile terminal is used as information for identifying the mobile terminal, and an IP address, a telephone number, an Ethernet or an optical Ethernet address, etc., assigned to an access routing agent to which the mobile terminal is currently connected. Through the concept of using the information to identify the current location of the mobile terminal can solve the problem caused by the IP address having both the identification information and the location information in the conventional Internet technology.

In particular, in the case of using the routing method according to the present invention, the problem of triangular routing through the home server generated in the conventional mobile Internet protocol is fundamentally solved, and maintaining and managing tunneling problems in the conventional protocol. The complex procedure for this is solved.

In addition, since complex processing procedures related to routing are handled at an agent level called an access routing agent, each terminal does not need to learn the location information of the other party, thereby having high security of the location information. have.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention. In describing the drawings, similar reference numerals are used for similar elements.

Terms such as first, second, A, and B may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component. The term and / or includes a combination of a plurality of related items or any item of a plurality of related items.

When a component is referred to as being "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that other components may be present in between. Should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that there is no other component in between.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

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

Routing method of mobile internet system according to the present invention

1 is a conceptual diagram illustrating a mobile internet system to which a routing method of a mobile internet system according to the present invention is applied.

Referring to FIG. 1, an operating environment of a mobile internet system to which a routing method of a mobile internet system according to the present invention is applied includes a mobile terminal 131 and a home that manages routing of a subnet to which the mobile terminal 131 originally belongs. Data packet sent from the mobile terminal 131 for the purpose of the server 110, the first access routing agent 121 and the mobile terminal 131 to support the mobility of the mobile terminal and provide Internet access Corresponding to the originating station 132 and the originating station 132 to receive the second access routing agent 122 to enable the Internet connection with the mobile terminal can be configured.

Herein, the mobile terminal 131 is a terminal capable of accessing the mobile internet, and is a terminal to which its own IP address is assigned. The terminal (Wibro or Wimax terminal) capable of accessing the mobile internet, a mobile communication terminal (cellular phone; CDMA, GSM, WCDMA, etc.), PDA (Personal Digital Assitance), notebook computer, UMPC (Ultra Mobile Personal Computer) and the like collectively.

In this case, the IP address assigned to the mobile terminal 131 may be IPv4 (32 bits) or IPv6 (128 bits).

The home server 110 is a component that is equivalent to or corresponds to a home agent (HA) defined in the conventional mobile Internet protocol (eg, RFC2002) and the like, and is a server that maintains data related to the mobile terminal, and is also a mobile terminal. Agent 131 is responsible for routing the subnet to which it originally belongs. On the other hand, the home server 110 has a binding database (corresponding to the IP address of the mobile terminal belonging to its own subnet and the address of the access routing agents to which each mobile terminal is currently connected, which will be described later.

In addition, the 'Access Routing Agent (121 or 122)' defined in the present invention is to enable the mobile Internet connection when the mobile terminal 131 is present on at least one side of the originating or receiving side. As a component, indirectly receives a data packet for the mobile terminal 131 and transmits it to the mobile terminal 131, and once receives the data packet sent by the mobile terminal 131 to the target station indirectly intended. It plays a role of sending.

As illustrated in FIG. 1, in the routing method of the mobile Internet system according to the present invention, the access routing agent is a second access routing agent 121 connected to the mobile terminal 131 and a second corresponding to the originating station 132. Access routing agent 122.

That is, the mobile terminal 131 and the originating station 132 are configured to indirectly send and receive Internet packets through the access routing agents 121 and 122.

The mobile terminal 131 and the first access routing agent 121 are wirelessly connected. In this case, there are various methods of wireless communication interface between the first access routing agent 121 and the mobile terminal 131, but Wibro, Wimax, cellular communication networks (CDMA, GSM, WCDMA), WLAN ( Various wireless communication methods such as IEEE802.11 series can be applied. In this case, the meaning that the mobile terminal 131 and the first access routing agent 121 are wirelessly connected is not only when the mobile terminal 131 and the first access routing agent 121 are directly wirelessly connected. It may include a case where the connection is performed as a tunnel including a wireless connection in some intervals.

The connection between the originating station 132 and the second access routing agent 122 may be wired or wireless. In other words, the originating station 132, like the mobile terminal 131, is another mobile terminal type terminal, and may wirelessly connect with the second access routing agent 122, or may be wired with the second access routing agent 122. It may be a terminal connected to. If the originating station 132 and the second access routing agent 122 are connected by wire, in most cases, the originating station 132 will be a terminal having a fixed location without mobility. In this case, the meaning that the originating station 132 and the second access routing agent 122 are wirelessly connected only when the originating station 132 and the second access routing agent 122 are directly wirelessly connected as described above. Rather, it may include a case in which some sections are connected as a tunnel including a wireless connection.

In this case, the first and second access routing agents 121 and 122 may be configured as if the home server 110 described above is an equivalent or corresponding component to the home agent HA defined in the conventional mobile Internet protocol (eg, RFC2002) or the like. It may be a component equivalent to or equivalent to a foreign agent (FA) defined in a conventional mobile internet protocol (eg, RFC2002). That is, the access routing agents 121 and 122 to which the routing method according to the present invention is applied may replace the functions of the external agent defined in the conventional mobile internet protocol, or may be configured as agents having additional functions added to the functions of the conventional external agent. Can be. In addition, the home server 110 and the access routing agents 121 and 122 described above may be implemented in the form of software or hardware additionally added to routers already included in the mobile Internet network.

Meanwhile, in the above-described FIG. 1, the home server 110 and the access routing agents 121 and 122 are distinguished from each other in terms of relative functional classifications assigned to the mobile terminal 131 and the originating station 132 at a specific time according to a situation. In addition, the home server 110 may also function as an access routing agent for other mobile terminals, and the access routing agent may be configured to function as a home server for other mobile terminals.

In addition, the name of the originating station 132 in Figure 1 is a view for explaining the routing method according to the present invention, it is only for explaining the originating station 132 as a subject for transmitting a packet to the mobile terminal 131, The roles of the terminal 131 and the originating station 132 may be varied. For example, the mobile terminal 131 may send a data packet for the purpose of the originating station 132. In this case, when the originating station 132 is also a mobile terminal, the routing method according to the present invention is applied in reverse.

2 is a flowchart illustrating a routing method of a mobile internet system according to the present invention.

Referring to FIG. 2, the routing method of the mobile Internet system according to the present invention may include a receiving step S210, an inquiry step S220, a transmitting step S230, and a delivery step S240. Hereinafter, each step included in the flowchart of FIG. 2 will be described in detail with reference to a conceptual diagram of the mobile Internet system illustrated in FIG. 1.

First, the receiving step (S210) is a step in which the second access routing agent 122 corresponding to the originating station receives the data packet for the mobile terminal 131 from the originating station 132.

That is, the originating station 132 sends the data packet to the second access routing agent 122 corresponding to the originating station by designating the IP address of the mobile terminal 131 that is the reception target as the recipient address. In this case, the 'data packet' may be an IP packet in which an IP address of a receiving target mobile terminal is written in a receiver address field.

Next, the inquiry step (S220) is a second access routing agent 122 corresponding to the originating station is the first that the mobile terminal is connected to the IP address of the mobile terminal 131 in a routing cache (142) When the address specifying the access routing agent 121 is inquired or the address specifying the first access routing agent 121 to which the mobile terminal is connected in the routing cache 142 is not found, the home server 110 may be used. In step 2), an IP address of the mobile terminal is searched for an address specifying the access routing agent 121 to which the mobile terminal is connected.

In this case, the address specifying the access routing agent 121 may be an IP address that uniquely identifies the access routing agent 121. In this case, the IP address may be IPv4 (32 bit) or IPv6 (128 bit). Or it may be an Ethernet address (Ethernet address) that can uniquely identify the access routing agent 121.

That is, various addresses capable of uniquely identifying the access routing agent may be used as an address for specifying the access routing agents 121 and 122. Can be used. For example, if the access routing agents are connected to a public telephone network or a mobile telephone network (IS-95, GSM, UMTS, PCS, etc.), the telephone number that is the address system of the public telephone network or the mobile telephone network specifies the access routing agents 121 and 122. Can be used as an address. For example, when access routing agents are connected through an Ethernet network, an Ethernet address (MAC address) may be used as an address specifying the access routing agent instead of an IP address. In particular, when the access routing agents are connected by an ehernet switch, it may be preferable that the Ethernet address of the access routing agent is used as an address specifying the corresponding access routing agent. On the other hand, when a new type of sub-network (eg, optical Internet) is introduced, an address based on an address system corresponding to the sub-network may be used as an address for specifying the corresponding access routing agent.

In the present invention, the inquiry step S220 may be defined as a MIRP procedure, and the second access routing agent 122 that receives the outgoing data packet from the originating station may receive the mobile terminal 131. Since the current location of the terminal cannot be determined, the first access routing agent 121 to which the mobile terminal 131 to which the reception target is currently connected in the routing cache 142 managed by the second access routing agent 122 itself is identified. Inquiry directly to the address, or through the home server 110 to query the address of the first access routing agent 121 is connected to the mobile terminal.

In this case, the IP address of the mobile terminal 131 and the address of the first access routing agent 121 to which the mobile terminal is currently connected are stored in the routing cache 142 of the second access routing agent 122 in correspondence. In this case, the address of the first access routing agent 121 queried in the routing cache is available. However, if there is no information related to the mobile terminal 121 in the routing cache, the home server 110 is associated with the mobile terminal 121. You will be asked for information.

In this case, when the mobile terminal 131 is connected to the home server 110, the home server 110 returns the IP address of the home server 110 to the second access routing agent 122. However, if the mobile terminal 131 is not connected to the home server 110 and is connected to the first access routing agent 121 instead of the home server 110, the home server 110 may access the first access routing agent 121. The address to be specified is returned to the second access routing agent 122.

In the inquiry step S220 described above, the inquiry request and the inquiry result delivery between the second access routing agent 122 and the home server 110 may be defined by defining a predetermined packet. For example, a predetermined packet form is defined between the second access routing agent 122 and the home server 110 in a form similar to the Internet Control Message Protocol (ICMP) protocol so that the second access routing agent 122 and the home server 110 can be defined. It can be configured to make the inquiry request and the inquiry result delivery between the defined packet form.

On the other hand, the second access routing agent 122 proceeds to the inquiry step (S220) via the home server 110 when the receiver of the data packet received from the originating station in the receiving step (S210) is a mobile terminal. In general, if the receiver is a fixed node rather than a mobile terminal, the data packet may be transmitted directly to the receiver, and there may be no need for indirect packet delivery through an access routing agent corresponding to the receiver. The second access routing agent 122 determines whether the receiver of the data packet received from the originating station is a mobile terminal or a stationary node other than the mobile terminal, for example, an IP address of the receiver included in the header of the data packet. It can be made using.

That is, if the IP address of the receiver is the IP address promised to be given in correspondence with the mobile terminal, the inquiry process is performed through the routing cache 142 or the home server 110, and the IP address of the receiver corresponds to the mobile terminal. In the case of an IP address that is not promised to be granted, a conventional routing procedure is performed without an inquiry step through the routing cache 142 or the home server 110. Alternatively, the access routing agent 122 uses the recipient IP address of the originating data packet itself without the process of determining whether the receiver of the data packet received from the originating station is a mobile terminal or a fixed node. It may be configured to determine whether to proceed with routing through 122 or send the data packet directly to the receiver. In this case, however, the originating terminal has a burden of having to carry out a database for individually determining which IP address is assigned to the mobile terminal or by adding a separate component to the system. . Therefore, it would be desirable to allow the access routing agent 122 maintained mainly by the operator operating the mobile Internet network to perform the above-described determination process in terms of system security or flexibility of maintenance.

On the other hand, in order to perform the above-mentioned inquiry step (S220), the access routing agent needs a space for storing a correspondence between the mobile terminal and the access routing agent, and the mobile terminal belonging to its own subnet also in the home server 110 And a predetermined database that stores the correspondence of the access routing agent to which each of the mobile terminals currently corresponds.

First, in the present invention, a database for performing the object existing in the home server is defined as a 'binding database 111'. That is, the binding database may be defined as a database in which binding information corresponding to IP addresses of mobile terminals registered in a home server and addresses of access routing agents to which terminals are currently connected are recorded.

Here, the term database is used as a generic term, including the case of a simple file-based list without regard to the form of a rigorous database such as relational or object-oriented. Can take the form of. In this case, the binding database prepared on the home server side may be included as a direct component of the home server 110, and may be stored in a separate server connected to the home server 110 by wire or wireless.

Next, in the present invention, a storage space for performing the object existing in the access routing agent includes a 'routing cache; 141 or 142).

As described above, the routing cache moves for the purpose of inquiring the address of the first access routing agent 121 to which the mobile terminal 131 to which data packet received by the second access routing agent 122 is sent. Terminals and mobile terminals need to keep a record of the access routing agents currently connected.

In addition, through the home server 110, the query of the first access routing agent to which the mobile terminal to be received is connected to the address of the first access routing agent, and then, the IP address of the mobile terminal and the first access routing agent to which the mobile terminal is connected. The addresses need to be mapped to the routing cache. That is, when a data packet for the mobile terminal 131 is received from other terminals connected to the originating station 132 and the second access routing agent 122 later, the second access routing agent 122 May directly query the IP address of the first access routing agent 121 to which the mobile terminal 131 is connected in the routing cache 142 without request for inquiry through the home server 110.

Conversely, in case a data packet for the originating station is generated from the mobile terminal, the IP address of the originating station and the address of the access routing agent to which the originating station is connected are matched for quick routing of the data packet to the originating station. You may need to keep a record. For example, the IP address obtained by decapsulating the data packet received by the first access routing agent is used to determine the address of the second access routing agent to which the calling station is connected, and thereafter, the second access routing to which the identified calling station is connected. The address of the agent may be used to transmit the data packet to a connected second access routing agent without passing through the home server. To this end, it may be necessary to record the IP address of the calling station and the address of the access routing agent to which the calling station is connected.

Routing caches 141 and 142 are non-volatile memory devices (NAND or NOR flash memory, etc.) and volatile memory devices (DRAM, SRAM) and hard disks (HDD) present in access routing agents 121 and 122. ) May be stored in a memory device formed of a combination of the above.

As mentioned, the access routing agent stores the routing cache as a repository that associates the IP address of the mobile terminal, which may be the destination of the IP packet, with the address of the access routing agent that governs the subnet to which the mobile terminal is currently connected. Can have On the other hand, the access routing agent needs to have a storage place for identifying and recording the IP address of the mobile terminal currently connected to its own subnet. The routing cache may also be used as such storage space.

Meanwhile, the role and detailed maintenance method of the routing cache and binding database will be described later.

In the transmitting step S230, the second access routing agent 122 to which the originating station is connected uses the address of the first access routing agent 121 to which the mobile terminal is connected to the data packet without passing through the home server. Directly transmitting to the first access routing agent 121.

At this time, the data packet is the IP packet received by the second access routing agent 122 from the originating station 132 in the receiving step (S210), the routing cache 142 or the home server 110 in the inquiry step (S220). From the access routing agent 122 to which the calling station is connected, the mobile station is encapsulized by adding a header including the address of the first access routing agent 121 connected to the receiver address as a recipient address. It may be configured to send to the connected access routing agent 121.

This encapsulation may be configured differently depending on which address is used as the address specifying the access routing agent, as described above. For example, if the access routing agent is specified as an IP address, the IP packet received from the originating station 132 may be encapsulated into an IP packet having the IP address of the first access routing agent 121 added to the header. That is, the encapsulation concept of the IP packet may be applied to the IP-in-IP scheme specified in RFC2003.

For example, if the access routing agent is specified as an Ethernet address, the IP packet received from the originating station 132 may be encapsulated into an Ethernet packet in which the Ethernet address of the first access routing agent 121 is added to the header. In other words, such encapsulation may be defined as Ethernet-in-IP.

Similarly, if the access routing agent is specified as a telephone number, the IP packet received from the originating station 132 includes the telephone number information of the first access routing agent 121 so that the packet suitable for the public telephone or mobile telephone network to which the access routing agents are connected. It may be encapsulated in the form of and transmitted to the first access routing agent 121.

Finally, the transmitting step (S240) is a step of delivering the data packet received by the first access routing agent 121 to the mobile terminal 131.

The first access routing agent 121 to which the mobile terminal 131 is connected decapsulizes the data packet received from the second access routing agent 122 in an encapsulated form in the transmission step S230 to depart the originating station 132. Restores the IP packet originally sent to the second access routing agent 122. Next, the first access routing agent 121 delivers the restored IP packet to the mobile terminal 131 currently connected to it by using the IP address of the receiver mobile terminal recorded in the header of the restored IP packet. .

In the routing method of the mobile Internet system according to the present invention described above, once the second access routing agent 122 knows the address of the first access routing agent 121 through the inquiry step (S220), the calling station (after All IP packets destined for the mobile terminal 131 from the 132 pass directly through the first access routing agent (1) without having to go through the home server 110 or repeat the inquiry step S220 for the home server 110. 121 may be transferred between the second access routing agent 122.

In addition, the routing method of the mobile Internet system according to the present invention, once the IP packet from the originating station is forwarded to the mobile terminal 131 via the first and second access routing agents 121 and 122, and then moves backwards. It may further include a routing method of the IP packet transmitted from the terminal 131 to the originating station 132.

For example, if an IP packet for the originating station 132 is generated from the mobile terminal 131, the IP packet is decapsulated from the IP packet decapsulated data packet received by the first access routing agent 121. The originating station 132 may know the address of the second access routing agent 122 to which it is connected. Subsequently, when a data packet for the identified originating station 132 is generated, it does not pass through the home server by directly using the address of the second access routing agent 122 to which the identified originating station 132 is connected. Or send the data packet directly to the second access routing agent 122 of the originating station.

Accordingly, the IP packet is transferred between the mobile terminal 131 and the originating station 132 by the second access routing agent 122 connected to the originating station of the first access routing agent 121 connected to the mobile terminal through the home server. Once the address is known, it can be configured as direct routing between access routing agents without the need to pass through a home server or create or maintain a tunnel between the home server and the access routing agent, as mentioned in the prior art. have.

As mentioned above, in the present invention, a storage cache in which an access routing agent stores routing information about a mobile terminal is defined as a routing cache, and a database in which a home server stores binding information about mobile terminals belonging to its own subnet. Is defined as the binding database. Hereinafter, a method of maintaining a binding database maintained by a routing cache and a home server in a routing method according to the present invention will be described.

How to Maintain the Routing Cache and Binding Database

In the inquiry step (S220) described above in FIG. 2, in order to respond to the inquiry request when the access routing agent 122 connected to the originating station makes an inquiry request to the home server of the access routing agent 121 to which the mobile terminal is connected. On the home server side, a predetermined binding database should be prepared. In addition, a predetermined routing cache should be prepared in the access routing agent 122.

Meanwhile, in order to maintain a predetermined binding database on the home server side, in the routing method of the mobile Internet system according to the present invention, the access routing agent collects the IP address of the mobile terminal belonging to its coverage area. need.

3 is a conceptual diagram illustrating a method of updating a binding database in a routing method according to the present invention.

Referring to FIG. 3, the access routing agent 121 searches for mobile terminals 131-1, 131-2, and 131-3 existing in its coverage area, and then routes IP addresses of the corresponding mobile terminals to its routing cache. 141 to record and manage. In addition, the home server 110 is the IP address of the mobile terminals originally belonging to its own subnet (in Figure 3 it is assumed that 131-1 and 132-2 belong to the subnet of the home server) and each mobile terminal is present Maintain a binding database 111 that stores addresses of connected access routing agents in association.

4 is a flowchart illustrating a method of updating a binding database in a routing method according to the present invention.

The updating method of the binding database in the routing method according to the present invention generally includes a discovery step in which an access routing agent connected to a mobile terminal identifies a mobile terminal belonging to a coverage area (S310), and the mobile terminal accesses an IP address of the mobile terminal. Recording (S320) the IP address of the mobile terminal recorded in the routing cache with the address of the access routing agent to which the mobile terminal is connected, and recording a predetermined period and / or The method may further include recording (S330) the binding database of the home server at the request of the access routing agent.

First, the step (S310) of the access routing agent identifying the mobile terminal belonging to the coverage area may be performed by a procedure such as agent discovery (discovery), agent registration (registration) of the conventional mobile Internet protocol.

For example, the mobile station 131-1 to 131-3 recognizes the network to which the mobile station belongs, and receives an agent advertisement message that the agents continuously broadcast at regular intervals. By performing registration, the access routing agent 121 can identify mobile terminals belonging to its own subnet.

Alternatively, the mobile terminals 131-1 to 131-3 broadcast a solicitation message without waiting for the advertisement message, and the access routing agent 121 that receives the response message responds to the mobile terminal 131-1 to 131. The access routing agent 121 can identify mobile terminals belonging to its own subnet by -3) knowing the network to which it belongs and proceeding with the registration procedure.

 Next, the access routing agent 121 performs a step (S320) of recording the IP addresses of the mobile terminals identified in the discovery step (S310) to the routing cache managed by the access routing agent. For example, the IP addresses of the mobile terminals 131-1 to 131-3 belonging to the subnet managed by the access routing agent are recorded in the routing cache 141 of the access routing agent 121, and additionally connected to each of the mobile terminals. Information such as type (eg, WiBro, cellular, WLAN, etc.), access time, etc. may be recorded (141-1).

Finally, the access routing agent 121 and the home server 110 checks the IP addresses of the mobile terminals recorded in the routing cache 141 of the access routing agent at a predetermined period and / or a request of the access routing agent or the home server. Transfer to home server and update binding database 111.

In FIG. 3, the mobile terminal 131-1 connected to the access routing agent 121 and the mobile terminal 132-2 connected to the access routing agent 122 belong to a subnet managed by the home server 110. It is assumed to be mobile terminals. Therefore, the IP address (157.153.2.1) of the mobile terminal 131-1 and the address of the first access routing agent 121 (in the case illustrated in FIG. 3, the IP address is used as an address specifying the access routing agent). Assuming, for example, 128.196.3.1 is associated and stored in the binding database 111, the IP address (157.128.1.1) of the mobile terminal 132-2 and the address of the second access routing agent 122 (e.g., In the case illustrated in FIG. 3, the IP address 128.128.5.3 is associated and stored in the binding database 111.

Meanwhile, the first access routing agent 121 transmits a request for directly updating the binding database of the home server, regardless of the step S320 of storing information related to the connected mobile terminal in its routing cache 141. This allows the binding database on the home server to be updated.

That is, omitting the step S320 of writing to the routing cache or irrespective of the progress of the step S320, if the first access routing agent 121 changes to the mobile terminal connected to its own subnet, the home is directly It may be configured to forward the update request of the binding database to the server 110.

At this time, in the case of the former (when updating to the binding database after writing to the routing cache), mobile terminals are not frequently moved, and an application suitable for the case where an immediate binding database update is not necessary is required. Since the communication between the home server and the access routing agent is made less by the cycle and / or the request of the access routing agent, the load of the home server can be reduced.

On the other hand, in the latter case (if updating the binding database irrespective of writing to the routing cache), the binding database update of the home server can be accessed as an application suitable for frequent movement of mobile terminals or immediate database update. Since the routing agent takes place immediately after the change of the mobile terminal existing in its coverage area, there may be a difference in that the load of the home server is increased because the amount of communication between the home server and the access routing agent increases.

Meanwhile, the routing cache 141 of the first access routing agent 121 and the routing cache 142 of the second access routing agent 122 illustrated in FIG. 3 are two parts 141-1 and 141-2, respectively. , 142-1 and 142-2).

The front ends 141-1 and 142-1 of the routing caches 141 and 142 store IP addresses and access information of mobile terminals currently connected to the subnet of the corresponding access routing agent. For example, three access terminals are connected to each of the access routing agents.

The rear end portions 141-2 and 142-2 of the routing caches 141 and 142 correlate and record the IP addresses of terminals identified by each access routing agent and the addresses of the access routing agents to which the terminals are currently connected. It is part. That is, in the inquiry step S220 described with reference to FIG. 2, the second access routing agent 122 identifies the first access routing agent 121 using the recipient IP address of the IP packet received from the originating station 132. The recording portion of the routing cache used for this purpose corresponds to the rear ends 141-2 and 142-2 of the routing caches 141 and 142.

At this time, the rear end portions 141-2 and 142-2 of the routing caches 141 and 142 are the addresses of the access routing agents that are inquired through the home server 110 and the target of the inquiry in the inquiry step S220. The IP address of the receiving station may be stored in association with each other, or the information obtained by inverse encapsulation of the data packet received by the access routing agent may be stored.

Meanwhile, the routing cache and the binding database have been described to record the one-to-one correspondence between the IP address of the mobile terminal and the address specifying the access routing agent. The query for the routing cache or the binding database also includes the IP address of the mobile terminal. It has been described to determine the address of the corresponding access routing agent using.

However, a method of writing IP addresses grouping IP addresses of mobile terminals existing in a coverage area by mapping them to a routing cache or binding database in correspondence with the addresses of the corresponding access routing agents. In this case, it is also possible to query the routing cache or the binding database for an access routing agent corresponding to the corresponding mobile terminals using the IP addresses grouping the IP addresses of the mobile terminals. In this case, a plurality of mobile terminals are described below with reference to FIG. 9A in a convenient manner for mobility support in a case where the mobile terminal is moved in a vehicle or the like.

Processing of Handover in Routing Method According to the Present Invention

On the other hand, in the mobile Internet to which the routing method according to the present invention is applied, the basic premise is to support mobility of a mobile terminal. Therefore, a handover should be made when the access routing agent to which the mobile terminal is connected is changed by the high speed movement of the mobile terminal.

The routing method according to the present invention additionally includes tunneling between the access routing agents, updating the routing cache between the access routing agents, and sharing the routing cache between the access routing agents in order to handle handover by the movement of the mobile terminal. May include selectively or in combination with fast handover support.

5 is a conceptual diagram illustrating tunneling and routing cache update in the handover processing method of the routing method according to the present invention.

Referring to FIG. 5, in the handover processing method of the routing method according to the present invention, the mobile terminal 131-1 connected to the first access routing agent 121-1 moves and the first access routing agent 121-1 moves. The purpose of this is to enable a handover that can prevent loss of data or delay of communication when connecting to 2).

First, when the first access routing agent 121-2 discovers a newly connected mobile terminal 131-1 by the discovery step S310 performed by the first access routing agent 121-2, The information of the mobile terminal 131-1 is recorded in the routing cache of the first b access routing agent 121-2, and the first a access routing agent 121-1 that the mobile terminal 131-1 has previously connected to. Tunneling is performed once between the newly connected 2b access routing agent 121-2.

The 1b access routing agent 121-2 requests the establishment of a tunnel for the 1a access routing agent 121-1 to which the mobile terminal 131-1 was previously connected. On the other hand, the second access routing agent 122, which has previously received a data packet for the purpose of the mobile terminal 131-1 from the originating station 132-3 and transmits it to the first access routing agent 121-1, has been previously established. Similarly, the data packet is transmitted to the 1a access routing agent 121-1. The first access routing agent 121-1 receives the first access routing agent 121-2 by using a tunnel established between the first access routing agent 121-2 and the first access routing agent 121-1. It will retransmit one data packet.

Second, the routing caches managed by the access routing agents 121-1, 121-2, and 122 and the home server 110 and the binding database are updated.

The above-described tunneling method is a temporary measure to prevent the loss of data packets sent from the originating station 132-3 for the purpose of the mobile terminal 131-1. When the tunneling method is repeatedly performed, too much tunneling occurs in the whole system, and problems in maintenance of the generated tunnels are caused. Therefore, in the present invention, tunneling is only used temporarily until the updating of routing caches and binding database managed by the access routing agents 121-1, 121-2, and 122 and the home server 110 is performed.

6A to 6D are conceptual views illustrating updating of a routing cache and a binding database in a routing method according to the present invention.

6A is a conceptual diagram illustrating an example of updating a routing cache of the first access routing agent 121-1 illustrated in FIG. 5.

Referring to FIG. 6A, the routing cache on the left side illustrates the routing cache before the update, and the routing cache on the right side illustrates the routing cache after the update. That is, in FIG. 6A, the mobile terminal 131-1 is connected to the first a access routing agent 121-1, and then moves to the first b access routing agent 121-2. The IP address and access information 201 of 1) are exemplified in the upper part 201 of the routing cache that records the terminals currently connected to the first access routing agent 121-1. However, the IP address of the mobile terminal 131-1 and the newly moved addresses of the access routing agent 121-2 (128.170.2.3) are mapped to each other to route the first a access routing agent 121-1 illustrated in FIG. 6A. 201-1 may be configured to record in addition to the lower end 202 of the cache.

Meanwhile, the routing information 202 existing in the routing cache before the update may be maintained in the routing cache after the update. The routing information 202 is information for mapping IP addresses of the access routing agents corresponding to the mobile terminal existing in the system, and the mobile terminal 131-1 to the first b access routing agent 121-2. This is because the routing information once collected may be used by the remaining terminals currently connected to the 1a access routing agent 121-1.

FIG. 6B is a conceptual diagram illustrating an example of updating a routing cache of the first b access routing agent 121-2 illustrated in FIG. 5.

As in FIG. 6A, the routing cache on the left side illustrates the routing cache before the update, and the routing cache on the right side illustrates the routing cache after the update. As the mobile terminal 131-1 is connected to the 1a access routing agent 121-1 and is moved to the 1b access routing agent 121-2, the IP address of the mobile terminal 131-1 is transmitted. And the connection information 203 is generated in the routing cache after the update.

Meanwhile, routing information 202 previously existing in the first access routing agent 121-1 is transferred to the first access routing agent 121-2 (204). This is because the routing information 202 is mapped to addresses of the access routing agents corresponding to the mobile terminal existing in the system by the mobile terminal 131-1 transferred to the first access routing agent 121-2. This is because it is not only likely to continue to be used in the future, but also may be used by the remaining mobile terminals previously connected to the 1b access routing agent 121-2.

FIG. 6C is a conceptual diagram illustrating an example of updating a routing cache of the second access routing agent 122 illustrated in FIG. 5.

6A and 6B, the routing cache on the left side illustrates the routing cache before the update, and the routing cache on the right side illustrates the routing cache after the update.

As the mobile terminal 131-1 moves from the 1a access routing agent 121-1 to the 1b access routing agent 121-2, the routing cache existing in the second access routing agent 122 is used. The IP address of the mobile terminal 131-1 (the IP address is 157.153.2.1) and the access routing agent to which the mobile terminal is connected should be changed. That is, the portion 205 which records and records the IP address 157.153.2.1 of the conventional mobile terminal 131-1 and the address (for example, IP address 128.196.3.1) of the first access routing agent 121-1. The change is made 206 to reflect the address (eg, IP address 128.170.2.3) of the newly moved and connected 1b access routing agent 121-2.

As illustrated in FIG. 6C, after the routing cache maintained by the second access routing agent 122 to which the originating station 132-3 is connected is updated, the mobile terminal 131-1 from the originating station 132-3 is updated. The data packets sent to may be directly transmitted without using a tunnel between the first access routing agent 121-1 and the first access routing agent 121-2.

Finally, FIG. 6D is a conceptual diagram illustrating an example of updating a binding database of the home server 110 illustrated in FIG. 5.

Also in FIG. 6D, the binding database on the left side illustrates the binding database before the update, and the binding database on the right side illustrates the binding database after the update.

The mobile terminal 131-1 is connected to the 1a access routing agent 121-1, and the mobile terminal 131-1 reflects that the mobile terminal 131-1 is moved to and connected to the 1b access routing agent 121-2. IP address (157.153.2.1) of the 1a access routing agent 121-1 corresponds to the address (128.196.3.1) is recorded (207), the address of the 1b access routing agent 121-2 (128.170.2.3) is changed to correspond to be recorded (208).

Meanwhile, as described above, the updating of the routing cache of the second access routing agent 122 as illustrated in FIG. 6C starts from the originating station 132-3 and the first access routing agent 121-1 and the first cache. 1b In the IP packet transmitted through tunneling between the access routing agents 121-2, the IP address of the originating station 132-3 is checked, and based on this, the second access routing agent connected to the originating station 132-3. By identifying 122 and requesting the second access routing agent to update the routing cache. For example, the mobile terminal 131-1 cancels such an update request during the tunneling process between the currently connected 1b access routing agent 121-2 or the previously connected 1a access routing agent 121-1. 2 may be forwarded to the access routing agent 122.

Conversely, when the mobile terminal 131-1 transmits a packet to the originating station 132-3 via the first access routing agent 121-2, which is a new access routing agent, the mobile station 131-1 transmits the packet to the originating station 132-3. The corresponding second access routing agent 122 may change the routing cache by itself using the IP packet transferred through the first access routing agent 121-2.

Finally, the above-described binding database update may be performed according to a predetermined period by the updating method of the binding database according to the present invention described with reference to FIG. 4, and in the situation in which the mobile terminal moves, the first or first access routing is performed. It may be made at the request of the agents 121-1 and 121-2.

7 is a conceptual diagram illustrating a routing cache sharing technique in the handover processing method of the routing method according to the present invention.

Referring to FIG. 7, the routing cache sharing scheme in the handover processing method of the routing method according to the present invention is the mobile terminal 131 connected to the first access router agent 121-1 as in the case illustrated in FIG. 5. Assume a case where N moves to connect to the first access routing agent 121-2 or the first access routing agent 121-3. In particular, an object of the present invention is to enable a quick handover that can prevent a delay of communication when changing the access routing agent to which the mobile terminal 131-1 is connected.

The mobile terminal 131 is currently connected to the 1a access routing agent 121-1, but can move to an adjacent 1b or 1c access routing agent 121-2 or 121-3 at any time. Accordingly, in the handover processing method of the routing method according to the present invention, in order to handle fast handover, not only the first a access routing agent 121-1 to which the mobile terminal is currently connected, but also the first a access routing agent 121-1. The contents recorded in the routing cache of the access routing agent 121-1 can be copied and shared in the routing cache of the 1a or 1b access routing agent 121-2 or 121-3 adjacent to .

As described with reference to FIG. 5, the handover processing method of the routing method according to the present invention includes a tunneling process and updating a routing cache between an access routing agent connected before the movement and an access routing agent connected after the movement. The process can be done.

Therefore, as illustrated in FIG. 7, when routing cache information is shared between adjacent access routing agents, the time required for packet delivery through temporary tunneling is minimized, and the routing cache information is updated between routing access agents. There is an advantage of minimizing the time it takes.

In addition, sharing routing cache information between adjacent access routing agents has an advantage of lowering the probability that an inquiry request from the access routing agent to the home server 110 occurs in the inquiry step S220 described above with reference to FIG. 2. have. In other words, by gathering routing information about mobile terminals collected from adjacent access routing agents and building mapping information between mobile terminals and access routing agents existing in the system by the access routing agents themselves, the inquiry through the home server is performed. This can have the side effect of reducing the overall system load and enabling fast routing.

Configuration of Access Routing Agent According to the Present Invention

8 is a block diagram showing an example of the configuration of an access routing agent of the mobile Internet system according to the present invention.

Hereinafter, the configuration of the access routing agent according to the present invention illustrated in FIG. 8 will be described in parallel with the conceptual diagram for explaining the routing method according to the present invention illustrated in FIG. 1.

Referring to FIG. 8, when the access routing agent 800 according to the present invention is the second access routing agent 122 corresponding to the originating station 132, the data packet receiver 810, the routing cache 820, and the data packet are provided. The transmitter 830 and the controller 840 may be configured as essential components. In addition, when the access routing agent 800 according to the present invention is the first access routing agent 121 connected to the mobile terminal 131, the mobile terminal discovery unit 850 may be further included.

On the other hand, since the access routing agent may be configured to perform the function of the second access routing agent and the function of the first access routing agent together, the above-described data packet receiver 810, the routing cache 820, and the data packet sender ( 830, the mobile terminal discovery unit 850 and the controller 840 may be configured to include all of them. In this case, the routing cache 820 is configured to simultaneously perform the role of the routing cache of the second access routing agent and the role of the routing cache of the first access routing agent.

Hereinafter, the roles and operations of the components of the access routing agent 800 illustrated in FIG. 8 will be described in the case where the access routing agent operates as the second access routing agent 122 and the access routing agent is the first access routing agent 121. Will be explained together.

When the access routing agent 800 operates as the second access routing agent 122, the data packet receiver 810 is connected to the originating station 132 to receive the data packet transmitted by the originating station. On the other hand, when the access routing agent 800 operates as the first access routing agent 121, the data packet receiver 810 is encapsulated from the originating station 132 and passed through the second access routing agent 122. Act as a component for receiving data packets.

Typically, the data packet receiver 810 is a wireless terminal using the Wibro, WiMax, mobile communication network (GSM, CDMA, WCDMA), WLAN (IEEE802.11) when the originating station 132 is a mobile terminal. The interface is available. When the access routing agent 800 operates as the first access routing agent 121, the data packet receiving unit 810 receives data packets routed and forwarded through the second access routing agent 122 mostly through wires. Will be.

The routing cache 820, when the access routing agent 800 operates as a second access routing agent 122, the IP address and the mobile terminal of at least some of the mobile terminals present in the mobile Internet system A component that associates and records the address of a connected first access routing agent. The information included in the routing cache 820 continuously accumulates the address of the access routing agent queried through the home server 110 and the IP addresses of the mobile terminals in the inquiry step S220 described with reference to FIGS. 1 and 2. It is created through the process.

On the other hand, when the access routing agent 800 operates as the first access routing agent 121, the routing cache 820 is the IP address of the mobile terminals determined to exist in the coverage area of the access routing agent. It will operate as a component that records. The maintenance method of the routing cache 820 is made through the discovery step S310 described with reference to FIGS. 3 and 4 and the step S320 of writing to the routing cache. In this case, when the access routing agent 800 operates as the first access routing agent 121, the mobile terminal discovery unit 850 identifies at least one mobile terminal existing in the coverage area and identifies the identified mobile terminals. A component that receives an IP address. The IP addresses of the mobile terminals identified by the mobile terminal discovery unit 850 are stored in the routing cache 820.

When the access routing agent 800 operates as the second access routing agent 122, the controller 840 determines whether the target receiver is the mobile terminal, and when the mobile terminal is the mobile terminal, the routing cache. In step 800, the address of the access routing agent to which the receiving mobile terminal is connected is inquired, or the IP address of the mobile terminal is accessed through a home server that manages the routing of the subnet to which the receiving mobile terminal belongs. The mobile station searches for the address of the access routing agent to which the mobile terminal is connected. In this case, the data packet transmitter 830 encapsulates the home server by encapsulating a data packet for the mobile terminal by using an address of an access routing agent currently accessed by the mobile terminal inquired through the routing cache or the home server. Rather than via the mobile terminal, the mobile terminal delivers the currently accessed access routing agent.

In addition, when the access routing agent 800 operates as the first access routing agent 121, the controller 840 is a home that manages the subnet to which the mobile terminal originally identified through the mobile terminal discovery unit 850 belongs. The mobile terminal may be configured to notify the server that the home terminal is connected to its own subnet so that the home server may update the binding database. The operation of the controller 840 may be described through the step S330 of recording to the binding database of the home server described with reference to FIGS. 3 and 4.

In this case, when the access routing agent operates as the first access routing agent, the data packet transmitter 830 decapsulates the received data packet to extract the recipient IP address and records the identified movement recorded in the routing cache. The terminal plays a role of delivering the decapsulated data packet to the mobile terminal corresponding to the recipient IP address among the terminals.

Subnet mobility support according to the present invention

When using the routing method of the mobile Internet system according to the present invention it is possible to simply manage the mobility of the subnet consisting of mobile terminals.

For example, when a plurality of mobile terminals form a group, it may be assumed that a plurality of mobile terminals are moved at the same time. That is, when a plurality of mobile terminals are located in a large transportation means such as a bus or a train, the positions of all the mobile terminals are moved at once by moving the bus or train.

In this case, the situation can be largely divided into two situations. First, the access routing agent corresponding to the plurality of mobile terminals is changed by moving the transportation means in which the plurality of mobile terminals are located. In this case, the mobile terminal and the access routing agent are moved together because the access routing agent corresponding to the plurality of mobile terminals and the mobile terminals are located together in the transportation means.

9A is a conceptual diagram for explaining an example of subnet mobility support using a routing method of a mobile Internet system according to the present invention.

Referring to FIG. 9A, an access routing agent 121-1 to 121-2 corresponding to mobile terminals by the first case described above, that is, the plurality of mobile terminals 131-1 to 131-N move at once. Is changed at the same time.

In this case, the plurality of mobile terminals 131-1 to 131-N that are moved at once are grouped to represent IP addresses of the plurality of mobile terminals in a single subnet form, thereby accessing the agents 121-1 and 121-2. If configured to write to the routing cache, mobility management of a plurality of mobile terminals can be simplified based on addresses grouped in this subnet form.

In FIG. 9A, N mobile terminals are located in a means of transportation such as a moving bus, so that N mobile terminals 131-1 to 131-N, 192.243.2.1 to 192.243.2.N, respectively, as the bus moves. It shows the situation that the IP address of) is moved together. In this case, instead of managing the binding database 901 in the home server 110 for each of the N mobile terminals, the binding database 901 manages an address (192.243.2. *) Grouping the N mobile terminals. Can be configured.

For example, the IP address of each of the 20 mobile terminals can be grouped in the form of 192.180.23.X for 20 mobile terminals having IP addresses of 192.180.23.1 to 192.180.23.20 in the binding database of the home server 110. There is no need to manage in, only the address grouped to 192.180.23. * Will be managed in the binding database of the home server 110.

In FIG. 9A, only the binding database 901 managed by the home server 110 is illustrated. However, in the routing cache managed by the access routing agents 121-1 and 121-2, N mobile terminals are grouped with an address (192.243). 2. *), each mobile terminal can be managed as a member of its own subnet. In this case, it is preferable that IP addresses capable of hierarchical grouping be allocated and used for mobile terminals moving in one transportation means. That is, it is preferable that IP addresses of 192.243.2.1 to 192.243.2.N are allocated to mobile terminals carried in one transportation vehicle in order to group the IP addresses of 192.243.2. *.

9B is a conceptual diagram illustrating another example of subnet mobility support using a routing method of a mobile Internet system according to the present invention.

Referring to FIG. 9B, an access routing agent corresponding to the second case described above, that is, the plurality of mobile terminals 131-1 to 131-N and the plurality of mobile terminals 131-1 to 131-N. The case where 121-1 moves together is illustrated. At this time, the access routing agent 121-1 again has an access routing agent 121-3 corresponding to the access routing agent.

That is, the access routing agent 121-1 functions as an access routing agent for the plurality of mobile terminals 131-1 to 131-N, and acts as a mobile terminal for its access routing agent 121-3. It will work. On the other hand, an access routing agent moving with a plurality of mobile terminals may be configured as a dedicated mobility access routing agent, but one of the plurality of mobile terminals moving may serve as an access routing agent. .

In the situation illustrated in FIG. 9B, a process of transmitting a data packet to one of the mobile terminals 131-1 of the plurality of mobile terminals 131-1 to 131-N by the originating station 132-3 is as follows. This can be done through a procedure.

Once the originating station 132-3 generates the data packet with the mobile terminal 131-1 as the receiver and sends it to the access routing agent 122, the mobile terminal 131-1 is connected through the home server. Check the address (128.196.3.1) of the access routing agent (121-1) (902-1), and again to the address (128.196.3.1) of the access routing agent (121-1) of the access routing agent (121-3) Check the address (128.196.3.2) (902-2).

Next, the access routing agent 122 encapsulates the original data packet into the packet to which the address of the access routing agent 121-1 is added, and once again to the packet to which the address of the access routing agent 121-3 is added. Encapsulation is sent to the access routing agent 121-3.

The access routing agent 121-3 extracts the data packet in which the access routing agent 121-1 is set as the receiver by decapsulating the data packet received from the access routing agent 122, and again, the access routing agent 121. Will be sent as -1).

Finally, the access routing agent 121-1 extracts the data packet in which the mobile terminal 131-1 is set as the receiver by decapsulating the data packet received from the access routing agent 121-3. -1).

At this time, the mobility management of the access routing agent 121-1 is the same as the mobility management of the conventional mobile terminal. For example, the access routing agent 121-1 and the mobile terminals 131-1 to 131-N move together to change the access routing agent corresponding to the access routing agent 121-1 (for example, 121-). In the case of 3 to 121-4, only the routing cache of the access routing agents 121-3 and 121-4 and the binding database of the home server 110 need to be changed corresponding to the access routing agent 121-1. .

Although described above with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below I can understand that you can.

1 is a conceptual diagram illustrating a mobile internet system to which a routing method of a mobile internet system according to the present invention is applied.

2 is a flowchart illustrating a routing method of a mobile internet system according to the present invention.

3 is a conceptual diagram illustrating a method of updating a binding database in a routing method according to the present invention.

4 is a flowchart illustrating a method of updating a binding database in a routing method according to the present invention.

5 is a conceptual diagram illustrating tunneling and routing cache update in the handover processing method of the routing method according to the present invention.

6A to 6D are conceptual views illustrating updating of a routing cache and a binding database in a routing method according to the present invention.

7 is a conceptual diagram illustrating a routing cache sharing technique in the handover processing method of the routing method according to the present invention.

8 is a block diagram showing an example of the configuration of an access routing agent of the mobile Internet system according to the present invention.

9A and 9B are conceptual views illustrating an example of subnet mobility support using a routing method of a mobile internet system according to the present invention.

<Description of drawing number for main parts of drawing>

810: packet receiver 820: routing cache

830: packet transmission unit 840: control unit

850: mobile terminal discovery unit

Claims (18)

A mobile terminal to which an IP address is assigned, a home server managing routing of a subnet to which the mobile terminal belongs, a first access routing agent wirelessly connected to the mobile terminal, and a sending station for sending data packets for the mobile terminal. And a second access routing agent corresponding to the originating station, the data packet routing method of the mobile internet system. A receiving step, wherein the second access routing agent receives a data packet sent by the originating station for the mobile terminal; The second access routing agent inquires an address specifying the first access routing agent by an IP address grouping an IP address of the mobile terminal or an IP address of the mobile terminal in a routing cache of the second access routing agent, or An inquiry step of inquiring an address for specifying the first access routing agent by an IP address grouping an IP address of the mobile terminal or an IP address of the mobile terminal through the home server; Transmitting, by the second access routing agent, the data packet to the first access routing agent without passing through the home server using an address specifying the first access routing agent queried; And And forwarding the data packet received by the first access routing agent to the mobile terminal. The method of claim 1, Wherein the first access routing agent and the second access routing agent have an address that uniquely specifies each, and an address specifying the first access routing agent and the second access routing agent is an IP address. Routing method of the Internet system. The method of claim 1, The first access routing agent and the second access routing agent each have an address that uniquely specifies, and the address specifying the first access routing agent and the second access routing agent is an Ethernet address. Routing method of the mobile Internet system. The method of claim 1, Wherein the first access routing agent and the second access routing agent have an address that uniquely specifies each, and wherein the addresses that specify the first access routing agent and the second access routing agent are telephone numbers. Routing method of the Internet system. The method of claim 1, The routing cache of the second access routing agent may include an address specifying an IP address of at least some of the mobile terminals existing in the mobile Internet system or an address grouping at least some IP addresses, and an access routing agent corresponding to the IP address. Routing method of the mobile Internet system, characterized in that stored in association. The method of claim 5, wherein In the querying step, when the IP address of the mobile terminal or the IP address grouping the IP address of the mobile terminal is grouped through the home server, an address specifying the first access routing agent is queried. And routing the IP address of the mobile terminal to an address specifying a routing agent and recording the same in the routing cache. The method of claim 1, The data packet is an internet protocol packet (IP packet), In the forwarding step, the originating station encapsulates an IP packet sent for the purpose of the mobile terminal by adding a header to which an address specifying the first access routing agent queried in the inquiry step is added. Routing method of the mobile Internet system, characterized in that for delivering data packets. The method of claim 7, wherein The first access routing agent is configured to determine an IP address of the originating station and an address specifying the second access routing agent by using the packet obtained by decapsulating the encapsulated IP packet and the encapsulated data packet. And associating an IP address of an originating station with an address specifying the second access routing agent and recording the same in the routing cache of the first access routing agent. The method of claim 8, When a data packet for the originating station is generated from the mobile terminal, In the routing cache of the first access routing agent, an address specifying the second access routing agent to which the calling station is connected is searched by using the IP address of the calling station, and the second access routing agent is not connected to the home server. Routing the data packet to a mobile internet system. The method of claim 1, Identifying, by the first access routing agent, a mobile terminal belonging to a coverage area; Recording the identified IP address of the mobile terminal or the identified IP address of the mobile terminal in a routing gash of the first access routing agent; And The IP address of the identified mobile terminal or the IP address of the identified mobile terminal recorded in the routing gash of the first access routing agent is associated with an address specifying the first access routing agent. Writing to the binding database of the home server at a cycle of and / or at the request of the first access writing agent, The querying step is a mobile Internet system, characterized in that for the request from the second access routing agent using the binding database to look up the address specifying the first access routing agent and to deliver it to the second access routing agent. Routing method. The method of claim 1, Identifying, by the first access routing agent, a mobile terminal belonging to a coverage area; And The IP address of the identified mobile terminal or the identified IP address of the mobile terminal is associated with an address specifying the first access routing agent, and the home server is requested by the first access routing agent. And further writes to the binding database, The querying step is a mobile Internet system, characterized in that for the request from the second access routing agent using the binding database to look up the address specifying the first access routing agent and to deliver it to the second access routing agent. Routing method. The method of claim 10 or 11, The binding database of the home server stores and stores an IP address of at least some of the mobile terminals existing in the mobile internet system or an address specifying an access routing agent corresponding to each of the at least some IP addresses. Routing method of the mobile Internet system, characterized in that. The method of claim 1, If the first access routing agent to which the mobile terminal is currently connected changes due to the movement of the mobile terminal, And routing the data packet for the mobile terminal received by the existing first access routing agent to the new first access routing agent through tunneling. The method of claim 1, If the first access routing agent to which the mobile terminal is currently connected changes due to the movement of the mobile terminal, The existing first access routing agent or the new first access routing agent analyzes the data packet transmitted from the originating station through the second access routing agent to determine an address specifying the second access routing agent, 2. The routing method of the mobile internet system of claim 1, wherein the new first access routing agent updates the corresponding information to the mobile terminal's routing cache. The method of claim 1, If the first access routing agent to which the mobile terminal is currently connected changes due to the movement of the mobile terminal, Copying information related to the mobile terminal from the routing cache of the existing first access routing agent to the routing cache of the new first access routing agent. The method of claim 1, And a first access routing agent to which the mobile terminal is currently connected shares information related to the mobile terminal recorded in the routing cache with adjacent access routing agents. A mobile terminal to which an IP address is assigned, a home server that manages routing of the subnet to which the mobile terminal belongs, a first access routing agent wirelessly connected to the mobile terminal, and a sending station for sending data packets for the mobile terminal. And a second access routing agent corresponding to the originating station, wherein the second access routing agent comprises: A routing cache that records and associates an IP address of at least some IP addresses or at least some IP addresses among mobile terminals existing in the mobile Internet system with an address specifying a first access routing agent to which the mobile terminals are connected. ; A data packet receiver for receiving a data packet transmitted by a calling station; The receiver determines whether the receiver of the data packet is a mobile terminal, and if the mobile terminal is a mobile terminal, inquires an address specifying a first access routing agent to which the mobile terminal is connected in the routing cache, or the mobile terminal belongs. A controller for querying an address specifying a first access routing agent to which the mobile terminal is connected through a home server that manages routing of a subnet; And The first access routing agent to which the mobile terminal currently connects is encapsulated by encapsulating a data packet for the mobile terminal using an address specifying a first access routing agent to which the mobile terminal is currently connected, without passing through the home server. An access routing agent, including a data packet sender that forwards to it. A mobile terminal to which an IP address is assigned, a home server that manages routing of the subnet to which the mobile terminal belongs, a first access routing agent wirelessly connected to the mobile terminal, and a sending station for sending data packets for the mobile terminal. And a second access routing agent corresponding to the originating station, wherein the first access routing agent comprises: A mobile terminal discovery unit for identifying at least one mobile terminal existing in the coverage area and receiving the identified IP addresses of the mobile terminals; A routing cache that records the identified IP addresses of the mobile terminals; A data packet receiver for receiving data packets from the outside; Data packet generation which decapsulates the received data packet to extract the recipient IP address and delivers the decapsulated data packet to the mobile terminal corresponding to the recipient IP address among the identified mobile terminals recorded in the routing cache. priest; And And a control unit configured to notify a home server managing a subnet to which the identified mobile terminal originally belongs to an IP address of the mobile terminal identified through the mobile terminal discovery unit and an address for identifying itself. Routing agent.

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