JP2004208053A - Communication system using global ip address, and method for securing communication - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a system and a method for solving the problems in the Mobile IP by directly transmitting data to a base station accommodated on the route at the time of an incoming call to a mobile terminal. <P>SOLUTION: A server for managing the location of the terminal in a network, namely, to which access node the terminal belongs is provided. The access node detects to which access node the mobile terminal belongs, and registers it to the server. A tag which is a combination of an IP address which is fixedly allocated to the mobile terminal and an identifier of the access node to which the mobile terminal belongs is managed. Transmission data is directly transmitted to the access node to which the mobile terminal is accommodated. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a communication system using a global IP address and a method for securing communication.
[0002]
[Prior art]
At present, in mobile communication, particularly in data communication using a mobile phone, an IP address is not fixedly assigned to the mobile phone terminal itself. For this reason, it is not possible to identify the mobile phone terminal that is the communication partner by the IP address.
[0003]
For this reason, outside the mobile communication carrier, the mobile communication terminal cannot be used on a carrier other than the carrier used by the mobile communication to be used, and the IP address is used from the beginning. Also, it was impossible to communicate (especially, communication using the Internet).
As for communication means using an IP address, there is Mobile IP as a solution for communication that is transparent to move (communicable while moving).
[0004]
However, regarding the communication in the incoming direction to the mobile terminal, since it is always sent to the home agent and then sent to the foreign agent where the mobile terminal is present, a loss due to route selection occurs. In practice, the more the number of hops increases, the more the overhead corresponding to the distance between the home agent and the foreign agent becomes. For example, if a communication terminal is “Tokyo” as a home agent, and this communication terminal is used between other communication terminals in Hokkaido, for example, in Hokkaido, this communication terminal is bothersome. First, communication is performed with the home agent in Tokyo, which is the home area of the terminal, and this agent is connected to a terminal in Hokkaido that wants to communicate via a base station or the home agent of the terminal that wants to communicate in Hokkaido. There is a situation where communication is finally established. In other words, since the home agent system is always informed and communicated, communication between terminals where both the transmitting terminal and the receiving terminal are located in Hokkaido is performed from the terminal (transmitting side) located in Hokkaido to Tokyo. The connection to the home agent, the communication from this home agent to the securing of the communication to Hokkaido (reception side) requires at least two large hops, and the location is extreme between the terminal of the calling party and the terminal of the other party However, while the distance is about 1 km, there is a situation where communication is performed at a distance exceeding 1000 km.
[0005]
Similarly, mobility transparency (so that existing sessions and services can be used irrespective of movement without change and mobile communication terminals moving on the network can be identified by an identifier that does not change). There is LIN6 as a communication means. However, in this method, there are restrictions on the configuration of the LIN6 general-purpose ID and the LIN6 address.
[0006]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2000-253068 [Patent Document 2]
JP-A-10-303981
[Problems to be solved by the invention]
The present invention has been made in view of the problems of the related art, and solves the problem included in Mobile IP by directly transmitting to an accommodated base station on a path at the time of an incoming call to a mobile terminal. The point that we can focus on. An object of the present invention is to provide a method of performing communication using an IP address fixedly assigned to a mobile terminal capable of communication.
[0008]
[Means for Solving the Problems]
The invention described in claim 1 is a communication system using an IP address fixedly assigned to a mobile terminal.
[0009]
According to a second aspect of the present invention, in a mobile communication, a global IP address is fixedly assigned to a mobile terminal, and communication is enabled using the global IP address without being restricted to a carrier of the mobile communication. A communication system characterized by the following.
[0010]
According to a third aspect of the present invention, in the first or second aspect, an access node that accesses the mobile terminal to a network via an IP address fixedly assigned to the mobile terminal, a gateway, and A communication system comprising: a tag management server that manages a fixedly assigned IP address and an identifier of the access node.
[0011]
According to a fourth aspect of the present invention, in the communication system according to the third aspect, the mobile terminal registers an IP address to be fixedly assigned via the access node and belongs to the communication system. is there.
[0012]
According to a fifth aspect of the present invention, in the third aspect, when the mobile terminal issues a TAG resolution request to secure communication with another mobile terminal, the tag management server transmits the TAG resolution request to the other mobile terminal. A tag, which is a combination of a fixedly assigned IP address of the other mobile terminal to reach the other mobile terminal and an identifier of an access node for causing the other mobile terminal to belong to the communication system, is stored in the database of the access node. And secures communication between the mobile terminal and the other mobile terminal.
[0013]
According to a sixth aspect of the present invention, in the fifth aspect, after securing the communication between the mobile terminal and the other mobile terminal, at least one of the mobile terminal or the other mobile terminal is connected to the mobile terminal. Requesting a tag addition request to newly add the tag to an access node other than the access node in which the tag is registered, and securing communication between the mobile terminal and the other mobile terminal. It is a communication system.
[0014]
According to a seventh aspect of the present invention, in any one of the third to sixth aspects, when the mobile terminal having a different carrier and the mobile terminal secure communication with each other, the gateway moves the mobile terminal having a different carrier. A communication system characterized in that communication is secured by holding a tag of a body terminal.
[0015]
The invention according to claim 8 provides an access node for accessing the network of the mobile terminal via an IP address fixedly allocated to the mobile terminal, a gateway, and a fixed IP address of the mobile terminal. A tag management server that manages an address and an identifier of the access node, the method comprising: securing a communication using a communication system, wherein the mobile terminal communicates with another mobile terminal. When the TAG resolution request is issued to secure the other mobile terminal, the tag management server sends the other mobile terminal a fixedly assigned IP address to reach the other mobile terminal and the other mobile terminal. A tag, which is a combination of the identifiers of the access nodes for causing the access node to belong to the communication system, is stored in the database of the access node It is a way to ensure communication characterized by Rukoto.
[0016]
The invention according to claim 9 is that, after securing communication between the mobile terminal and the other mobile terminal, at least one of the mobile terminal or the other mobile terminal has a tag registered. 9. The communication between the mobile terminal and the other mobile terminal by securing a tag addition request to newly assign the tag to an access node other than the access node that has performed the communication. This is a method of securing communication.
[0017]
According to a tenth aspect of the present invention, in the eighth or ninth aspect, when the mobile terminal having a different carrier and the mobile terminal secure communication with each other, the gateway sets the mobile terminal having the different carrier. 10. The method for securing communication according to claim 8, wherein the communication is secured by holding a tag.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
The present invention is based on a W-CDMA system in which the same frequency band is used in a mobile phone in mobile communication, especially in an adjacent base station / cell, and relates to a handover between base stations. Further, the present invention is a takeover method for allowing a mobile terminal such as a PDA to continue communication seamlessly between hot spots which are base stations of an open wireless LAN.
[0019]
<First embodiment>
FIG. 1 is an example (model network) for explaining the configuration of the present invention. Each access node (Access Node) 11 to 12, 21 to 22, and 31 to 32, which are network components in the present invention, a gateway (GW) 21, a tag management server (hereinafter, referred to as TMS) 31 And a mobile terminal to which a unique global IP address is assigned (a mobile terminal to which only one global IP address is assigned to one terminal).
[0020]
The access nodes 11 to 32, the GW 21, and the TMS 31 are connected using an IP network (Internet protocol network: for example, a public line), and perform communication using an IP address of each device (each mobile terminal).
In the access nodes 11 to 32 and the GW 21, IP addresses of TMS are registered in advance.
In the present invention, the TMS 31 manages the location of the terminal in the network, that is, which access node the terminal belongs to, and manages a tag (TAG) used for communication between the devices. is there. The TMS receives a TAG registration request from a mobile terminal via each access node, and identifies a mobile terminal identification number (IP address assigned to the terminal) and an access node identification number (IP address assigned to the access node). Is stored in the database (in the TMS).
[0021]
The combination of the mobile terminal identification number and the access node identification number is used as a TAG in the communication system of the present invention. After this registration, when a TAG resolution request is received from any of the network constituent devices, the mobile terminal identification number on the signal is extracted, and the corresponding access node identification number (identifier) is searched from the database. The TAG resolution request is returned to the network component device that sent the request. At this time, if a plurality of access node identification numbers are registered for one mobile terminal identification number, all registered access node identification numbers are returned as a TAG list.
[0022]
The access nodes 11, 12, 21, 22, 31, and 32 are devices that terminate the radio of each mobile terminal and relay communication. Detecting the affiliation of each mobile terminal to the network (at which access node the mobile terminal is terminated) and registering a TAG in the TMS, and as each mobile terminal moves, this mobile terminal When a certain access node becomes out of the management target, the TAG is deleted (the access node can request the TMS, and the access node where the TAG exists deletes the TAG existing in this access node itself. be able to). Also, when each mobile terminal tries to communicate and there is no access node accommodating the communication partner of each mobile terminal, and the mobile terminal without the access node wants to communicate with a certain communication partner , (Or outside the carrier) wants to communicate with a communication partner (a mobile terminal that is controlled by an access node because a tag is present at the access node) in the system, A TAG is notified between a mobile terminal having no access node (or a mobile terminal outside a carrier) and the GW to establish a communication path.
[0023]
The GW plays a role of a bridge between the network and the outside when the communication is not within the same mobile communication providing carrier, that is, when performing communication with the outside.
A mobile terminal A and a mobile terminal B exist in this model network. The mobile terminal B terminates its own radio as it moves. That is, the accommodated access node changes as needed. These nodes are represented by B1, B2, and B3, respectively, in FIG. That is, it is assumed that the mobile terminal B first accesses the terminal from the access node 21 and then the access node to be terminated changes to 22, 32 due to the movement of the mobile terminal B. ing.
[0024]
<Operation of First Embodiment>
FIG. 2 shows a sequence until the mobile terminal is recognized as belonging to the network.
As shown in FIG. 2, when the mobile terminal tries to belong to a specific network, the mobile terminal periodically sends a TAG registration request until it confirms that the terminal belongs to a specific network. Transmission is continued (step T1 → step T2). Although the mobile terminal itself generally does not know from which access node, when a certain access node (for example, the access node 11) makes a registration request to the TMS, the TMS registers this request by ( Step T3), the TAG registration completion report is received by the certain access node 11 of this network, via the access node, indicating that the TAG registration has been completed (step T5). Thus, the procedure in which the mobile terminal A belongs to this network is completed. FIG. 2 illustrates an example in which mobile terminal A has performed a TAG registration procedure with Access Node 11. However, the mobile terminal does not recognize with which access node it is performing wireless signal exchange. Completion of the TAG registration means that the corresponding mobile terminal has been registered in the TMS. At this time, the mobile terminal belongs to the network. The mobile terminal may be configured to recognize which access node it is accessing, or to display (on the mobile terminal itself).
[0025]
FIG. 3 shows that the mobile terminal A has already been terminated at the access node 11 and the mobile terminal B has been terminated at the access node 21 by the procedure belonging to the network. On the premise that the communication between the two mobile terminals is started. When the mobile terminal A makes a call to perform communication with the mobile terminal B (step S1), the access node 11 receives this signal and makes an inquiry to the TMS for tag resolution (step S2). In order to presuppose such recognition, the TMS may be set to have a monitoring function. In some cases, this function may be provided to the GW.
[0026]
As a result, a tag for reaching mobile terminal B is notified as “B-21”, and the destination is transmitted as access node 21 from this TAG. Here, the access node 11 stores its own TAG “A-11” and the other TAG “B-21” in its own database (step S3). The access node 21 accommodating the mobile terminal B via the public IP network receives the connection request, and stores its own TAG "B-21" and the other TAG "A-11" in its own database (access). It is stored in the node 21) (step S4), and a series of connection sequences (steps S4 to S) as shown in FIG. 3 are processed. Thus, a communication path is established. After step S4, in the two-way communication, the access node sets the TAG of the own side / the other side and exchanges signals, so that the terminal A and the terminal B perform end-to-end communication. Is performed.
[0027]
FIGS. 4 and 5 describe a TAG solution method when the mobile terminal B moves away from the access node 21 and moves toward the access node 22. FIG. That is, as shown in FIG. 1, a case where the position is moved from the position B1 to the position B2 is shown. When the mobile terminal B detects that the radio quality has deteriorated with the access node, that is, the mobile terminal B has separated from the access node (step S100), the mobile terminal B performs an operation to resolve the radio quality by connecting to another access node. Do. Until the radio quality is resolved, the tag addition request including the identification number of the currently-communicating mobile terminal and the identification number of the own mobile terminal is continuously transmitted (step S101). Even if the access node 21 receives and recognizes the tag addition request, it is determined that the access node 21 itself has already operated the communication of the mobile terminal B (continuation (continuation) or deterioration of radio quality deterioration: The determination is performed using a known method, for example, when the communication level becomes lower than a certain threshold, it is determined to be worse.) Accordingly, the access node 21 discards the tag addition request. The access node 22 detects the reception of the tag addition request in accordance with the approach of the mobile terminal B (that is, for example, when a threshold is set in the communication level and the threshold is equal to or exceeds this threshold), and is controlled by the own node as network belonging information. The presence of the mobile terminal B is registered in the TMS (step S102). When the registration for TMS is completed, the tag resolution of the mobile terminal A which is the communication partner of the mobile terminal B is performed (steps S104 to S105). As a result, the access node 11 accommodating the mobile terminal A is Then, it notifies that the number of communication paths for the mobile terminal B has increased by a partner tag addition request (steps S106 and S107). The subsequent steps are as shown in FIG. That is, the access node 11 additionally registers “B-22” as a partner tag in association with the self-side tag “A-11” (step S108). Is reported in the tag addition notification. The mobile terminal A recognizes, by the tag addition notification, that the number of communication paths on the partner side has increased, and allows diversity reception. Thereafter, the mobile terminal B performs communication with a plurality of communication paths as a handover transition period.
[0028]
FIG. 6 shows that the mobile terminal B having two communication paths further comes closer to the access node 22 by having two access nodes 21 and 22 and disconnects communication with the access node 21. And a sequence for completing the handover. The mobile terminal B releases the other communication path when it determines that one of the communication paths has sufficient wireless quality in a state in which two communication paths are held, that is, in a handover transition period. The mobile terminal B transmits a communication path release request to the access node 21 (Step S211). In the example illustrated in FIG. 6, since the communication node moves away from the access node 21 and moves toward the access node 22, the communication path release request is made to the access node 21. A TAG deletion request is issued to the TMS to delete the “B-21” TAG from the tag management on the network (step S212), and the “B-21” tag is also sent to the access node 11 using this tag. To delete. When this series of sequences is completed, the handover of the mobile terminal B is completed, and the mobile terminal B belongs to this network only via the access node 22 (steps S211 to S217).
[0029]
FIG. 7 shows a case where the mobile terminal A performs communication with a carrier other than the carrier used by the mobile terminal A. The TMS provides a GW tag (where?) When it is required to resolve an IP address a that cannot be managed by itself. An access node (in FIG. 7, access node 11: in the following description of FIG. 7, an example in which the access node 11 is used will be described) is conscious of whether the tag of the destination is an access node or a GW. Without (basically not recognizing), a connection request is made using the tag provided from the TMS, that is, for the GW (step S304). The GW returns a response to the connection request to the access node 11 that has transmitted the connection acceptance (step S305). Thereafter (steps S307 to S310), communication is performed between the mobile terminal and a communication partner outside the carrier using this communication path. Upon receiving a communication event from the outside, the GW extracts the destination IP address, that is, the mobile terminal identification number, and transmits it to the mobile terminal using the tag corresponding to the destination IP address. As described above, when performing communication with a terminal or the like outside the carrier, the GW has both functions as an access node and a defense function (such as a firewall).
[0030]
FIG. 8 shows a case where communication with the mobile terminal from outside the carrier occurs outside the system being communicated on the same carrier as shown in FIG. The GW receives a communication event from outside the carrier (step S401). If the GW does not have the TAG of the destination mobile terminal identification number, the GW issues a tag resolution request to the TMS (step S402). Thereafter, as in the case between the two access nodes, the tags are exchanged between the GW and the access node according to the connection request, and communication is performed (steps S404 to S415). In this case, since the GW communicates with a terminal or the like outside the carrier, the GW functions as an access node as in FIG. 7, and the GW has both functions of a defense function (firewall and the like) to the outside. Become.
[0031]
<Second embodiment>
Although the present invention assumes a mobile phone as a mobile terminal, the present invention can be applied to an open wireless LAN in addition to a WAN as shown in FIG. 1 by replacing an access node with a hot spot.
Further, the public IP network is taken as an example of the backbone network (communication line). However, the protocol of the backbone network is not particularly limited as long as the tag can be resolved. For example, if ATM (asynchronous transfer mode) is used for the backbone, VPI / VCI may be applied as a tag as a means for reaching each device.
[0032]
【The invention's effect】
In the present invention, the mobile terminal, the access node corresponding to the base station, and the TMS that provides a means for reaching each mobile terminal are exclusively constructed, and a public IP network is used, which is equivalent to W-CDMA. (Communication whose quality can be guaranteed) can be realized, and communication using the IP address to which each mobile terminal is fixedly assigned can be performed as it is. Such communication can be made communicable with each country (across borders) with a quality equivalent to that of an Internet telephone by a method completely different from that of an Internet telephone. That is, in the present invention, the communication method is a communication equivalent to (communication whose quality can be guaranteed) equivalent to W-CDMA and has a function of integrating two communication of the Internet telephone.
[0033]
The present invention can solve the problem included in Mobile IP because it is directly transmitted to the accommodated base station on the path at the time of arrival at the mobile terminal.
In the present invention, since the IPv6 address is assigned to each of the network constituent device and the mobile terminal as it is, tunneling is performed between the network constituent devices, and the IP address of the mobile terminal is transferred as it is, the 128-bit address space is used without restriction. Can do things.
[Brief description of the drawings]
FIG. 1 is a diagram showing an example of a model network for explaining a configuration of the present invention.
FIG. 2 is a sequence diagram until a mobile terminal belongs to a network and is recognized.
FIG. 3 is a sequence diagram from when the mobile terminal A is already terminated at the access node 11 and the mobile terminal B is terminated at the access node 21, and the communication between the two mobile terminals is started.
FIG. 4 is a sequence diagram illustrating a process of TAG resolution when mobile terminal B moves away from access node 21 and moves toward access node 22;
FIG. 5 is a sequence diagram illustrating a TAG solution method when the mobile terminal B moves away from the access node 21 and moves toward the access node 22;
FIG. 6 is a diagram illustrating a mobile terminal B having two communication paths due to having two access nodes 21 and 22. The mobile terminal B disconnects from the access node 21 when the mobile terminal B approaches the access node 22 and performs handover. FIG. 7 is a sequence diagram up to the completion of FIG.
FIG. 7 is a sequence diagram showing a case where the mobile terminal A performs communication with a carrier other than the carrier used by the mobile terminal A.
FIG. 8 is a sequence diagram showing a case where communication from outside the carrier to a mobile terminal occurs.
[Explanation of symbols]
TMS Tag Management Server 11, 12, 21, 22, 31, 32 Access Node GW Gateway

Claims (10)

A communication system using an IP address fixedly assigned to a mobile terminal. A communication system wherein a global IP address is fixedly assigned to a mobile terminal in mobile communication, and communication is enabled using the global IP address without being restricted to a carrier of mobile communication. An access node for accessing the mobile terminal via a network via an IP address fixedly assigned to the mobile terminal;
A gateway,
A tag management server that manages a fixedly assigned IP address of the mobile terminal and an identifier of the access node;
The communication system according to claim 1, further comprising: The communication system according to claim 3, wherein the mobile terminal registers an IP address that is fixedly assigned via the access node and belongs to the communication system. When the mobile terminal issues a TAG resolution request to secure communication with another mobile terminal, the tag management server sends a fixed request to the other mobile terminal to reach the other mobile terminal. A tag, which is a combination of the IP address assigned to the access node and the identifier of the access node for causing the other mobile terminal to belong to the communication system, is stored in the database of the access node, and The communication system according to claim 3, wherein communication with the mobile terminal is secured. After securing the communication between the mobile terminal and the other mobile terminal, at least one of the mobile terminal or the other mobile terminal is connected to an access node other than the access node whose tag is registered. The communication system according to claim 5, wherein a communication between the mobile terminal and the other mobile terminal is secured by requesting a tag addition in order to newly add a tag. The mobile terminal having a different carrier and the mobile terminal, when securing communication, the gateway holds a tag of the mobile terminal having a different carrier to secure communication. 7. The communication system according to any one of 6. An access node for accessing the mobile terminal to the network via an IP address fixedly assigned to the mobile terminal; a gateway; a fixedly assigned IP address of the mobile terminal and an identifier of the access node. And a tag management server to manage, using a communication system comprising:
The method comprises:
When the mobile terminal issues a TAG resolution request to secure communication with another mobile terminal, the tag management server transmits a fixed TAG of the other mobile terminal to reach the other mobile terminal. And storing a tag, which is a combination of an IP address assigned to the access node and an identifier of an access node for causing the other mobile terminal to belong to the communication system, in a database of the access node. After securing the communication between the mobile terminal and the other mobile terminal, at least one of the mobile terminal or the other mobile terminal is connected to an access node other than the access node whose tag is registered. The method for securing communication according to claim 8, wherein the communication between the mobile terminal and the other mobile terminal is secured by requesting a tag addition to newly add a tag. Further, when the mobile terminal having a different carrier and the mobile terminal secure communication, the gateway holds the tag of the mobile terminal having the different carrier to secure the communication. 10. The method for securing communication according to 8 or 9.

Images