JP2000059416A - Gateway - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a gateway that transfers a request packet addressed to a server and arrived from a client and allows the server to receive this request packet. SOLUTION: A private address of a server 103 is registered in a private address registration section 108 and a global address for access to the server 103 is registered to a through-address registration section 109. An address comparator section 110 compares the address of a received packet with an address registered in the through-address registration section 109 and when the address is the same, the comparator section 110 gives the address to an address conversion section 111, where the address of the received packet is converted into an address, that is registered in the private address registration section 108. With this configuration, a packet is transmitted from a client in a global address network to a server of a private address network.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a gateway device.

[0002]

2. Description of the Related Art Conventionally, IP (global) addresses used in Internet Protocol (IP), which is an Internet protocol, are being depleted, and in order to solve the problem, use of private IP addresses is progressing. . However, there is a problem that a private address network cannot directly communicate with a global address network. In order to solve this problem, a technology has been developed in which an address translation router for translating between a private address and a global address is installed to enable mutual communication. The technology related to this is disclosed in, for example, Japanese Patent Application Laid-Open No. 7-30575.

[0003] Also, RF, which is a rule of the Internet.
It is also defined in C1631 (Network Address Translator).

In such a technique, when a client in a private address network transmits a request packet to a server in a global address network, the gateway device performs address conversion. By storing the private address of the client at that time, when the response packet returns from the server, it is converted to the stored address. Thus, the packet can be transmitted from the server to the client.

[0005]

However, according to the above-mentioned prior art, a client on a global address network cannot access a server on a private address network. This is because the client cannot know the private address of the server. Even if the private address of the server can be known, a packet with the private address cannot be transmitted to the global address network.

The present invention has been made in view of the above problems, and provides a gateway device capable of transferring a request packet addressed to a server arriving from a client and allowing the server to receive the request packet from the client. With the goal.

[0007]

The present invention adopts the following constitution in order to solve the above problems.

The gateway device of the present invention registers an address of a server having a private address, registers a global address for a client to access the server, and transmits / receives a packet to / from a global address network and a packet to / from a private address network. . The address of the received packet is compared with the registered address, and if they are the same, the packet is converted to the registered address and transmitted.

With this configuration, it is possible to transmit a packet from a client on the global address network to a server on the private address network by registering the address of the server in advance and converting the address of the request packet.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention relating to a gateway device according to claim 1 is a gateway device connected to a global address network connected to a client and a private address network connected to a server, and has a private address. A private address registration unit for registering a server address, a through address registration unit for registering a global address for a client to access the server, a global address I / F for transmitting / receiving packets to / from a global address network, and a private address network A private address I / F for transmitting and receiving packets and a received packet address are compared with an address registered in a through address registration unit.
If they are the same, an address comparing unit that transmits to the address translating unit, an address translating unit that translates the address of the received packet into an address registered in the private address registering unit, and transmits the address to the private address I / F,
Is adopted.

With this configuration, it is possible to transmit a packet from a client on the global address network to a server on the private address network by pre-registering the address of the server in the gateway device and converting the address of the request packet. Becomes

According to the second aspect of the present invention, a configuration is adopted in which a request packet from a client on the global address network can be transferred to a server on a private network registered in advance.

According to a third aspect of the present invention, there is provided a gateway device connected to a global address network connected to a client and a private address network connected to a server. A private address registration unit for registration, a global address I / F for transmitting / receiving packets to / from the global address network, a private address I / F for transmitting / receiving packets to / from the private address network, and a port number used by the gateway device A port registration unit for registering the port number, and checking whether the port number of the packet received from the global address I / F is included in the port number registered with the port registration unit. If not, a port comparing unit for sending to a subsequent address converting unit, the address converting unit for converting the address of the received packet to an address registered in the private address registering unit, and transmitting the address to the private address I / F; Is adopted.

According to this configuration, by transmitting only a request packet of a port number not used by the gateway device to the server, the global address of the gateway device can be shared between the gateway device and the server device, and only one global address is transmitted. Addresses allow both the gateway device and the server to process requests from clients.

According to a fourth aspect of the present invention, a request packet addressed to a port number not used by the gateway device can be transferred to a server.

According to a fifth aspect of the present invention, there is provided a gateway device connected to each of a global address network connected to a client and a private address network connected to a server. A private address registration unit for registration, a global address I / F for transmitting / receiving packets to / from the global address network, a private address I / F for transmitting / receiving packets to / from the private address network, and a port number used by the gateway device A port registration unit for registering a port, a remote port registration unit for registering a port used by the server and a private address, and a port for a packet received from the global address I / F. If the port number is not included in the port number registered in the port registration unit and is included in the port number registered in the remote port registration unit, a port comparison unit that sends a packet to the address translation unit; Is converted to an address registered by the remote port registration unit and transmitted to the private address I / F.

With this configuration, the server registers the port number to be used in the remote port registration unit. The registration is realized by transmitting a packet including a port number and a server address. The remote port registration unit manages servers and their port numbers in a remote port management table. In the remote port management table, a plurality of servers can be registered by registering a plurality of port numbers and server addresses.

According to the present invention, the port number of the request packet received from the client is checked.
A configuration is adopted in which transfer can be made to a server waiting on that port number.

Next, a gateway device according to an embodiment of the present invention will be described in detail with reference to the drawings. 1 to 5 are diagrams for explaining a configuration according to an embodiment of the gateway device of the present invention.

(Embodiment 1) FIG. 1 is a system block diagram to which a gateway device according to Embodiment 1 of the present invention is applied.

In FIG. 1, a system to which the present gateway device is applied includes a client 101 for transmitting a request packet, a global address network 102, a server 103 for processing the request packet, a private address network 104, and a request from the client transferred to the server. It is configured by a gateway device 105 that performs the communication.

The gateway device 105 is subdivided into a global address I / F 106 for receiving a packet from a global address network, a private address I / F 107 for transmitting a packet to a private address network, and a private address registration for registering a server address. Unit 108, a through address registration unit 109 for registering a through address, an address comparison unit 110 for comparing the address of a packet received from the global address I / F, an address conversion unit 111 for converting a packet address, and a communication protocol of the gateway device itself. It is configured by the unit 112.

The operation of the gateway device configured as described above will be described below.

The user uses the through address registration unit 109 to register a global address (or a through address) for the client 101 to access the server 103. This address needs to be different from the address used by the gateway device 105 itself. Further, the user registers the private address of the server 103 using the private address registration unit 108.

Next, the client 101
To the through address.
The request packet is sent to the global address network 10
The request packet arrives at the global address I / F 106 of the gateway device 105 via the communication device 2, and the request packet is sent to the address comparing unit 110.

The address comparing unit 110 compares the address registered by the through address registering unit 109 with the address of the request packet.
Sent to If they are not the same, it is a request packet to the gateway device 105 itself, so that the communication protocol unit 1
12 is sent.

The address conversion unit 111 stores the address of the received request packet in the private address registration unit 1
In step 08, the address is converted into the private address of the registered server and passed to the private address I / F 107. The private address I / F 107 can transmit the packet to the server via the private address network 104.

As described above, the address of the server 103 is registered in the gateway device 105 in advance, and by converting the address of the request packet, the packet is transmitted from the client 101 on the global address network to the server 103 on the private address network. Can be sent.

(Embodiment 2) FIG. 2 is a block diagram showing a configuration of a gateway device according to Embodiment 2 of the present invention. In FIG. 2, the same functional blocks as the configuration blocks shown in FIG.
It has the same sign.

In FIG. 2, a gateway device 205 according to the second embodiment includes a port registration unit 201 for registering a port number used by the gateway device 205, a port number of a packet and a port number used by the gateway device. And a port comparison unit 202 for comparing Other components are the same as those of the first embodiment.

The operation of the gateway device 205 configured as described above will be described below with reference to the block diagram of FIG.

First, as in the first embodiment, the user uses the private address registration unit 108 to
03 address is registered. In addition, the communication protocol unit 1
12 registers the port number used by the gateway device 205 in the port registration unit 201. When the communication protocol is TCP / IP and the WWW server is operated by the gateway device, the gateway device 205 generally uses the port number 80.
Register 0.

Unlike the first embodiment, the client 101 transmits a request packet to the server 103 when transmitting the request packet to the server 103. At this time, the global address I / F 106 of the gateway device 205
Receives the request packet and sends it to the port comparison unit 202. If the port number of the request packet is included in the port number registered in the port registration unit 201, the port comparison unit 202 compares the request packet with the communication protocol unit 1.
If it is not included in the address, the address is sent to the address conversion unit 111.

Address conversion section 111 performs address conversion in the same manner as in the first embodiment, and transmits a request packet to server 103.

As described above, by transmitting only the request packet of the port number not used by the gateway device 205 to the server 103, the global address of the gateway device 205 can be shared between the gateway device 205 and the server device. The request from the client can be processed by both the gateway device 205 and the server 103 with only one global address.

(Embodiment 3) FIG. 3 is a block diagram showing a configuration of a gateway device according to Embodiment 3 of the present invention. 3, the same reference numerals are given to the same functional blocks as those shown in FIGS. 1 and 2 applied to the first and second embodiments.

In FIG. 3, the gateway device 305 according to the third embodiment includes a server 30 for processing a request packet.
1. It has a remote port registration unit 302 for registering a port number used by the server, and an address conversion unit 303 for converting the address of a packet. Other components are the same as those of the first or second embodiment.

The operation of the gateway device configured as described above will be described below with reference to the block diagram of FIG.

FIG. 4 shows a remote port registration packet format according to the third embodiment. Also, FIG.
15 shows a configuration example of a remote port management table according to the third embodiment.

First, the server 301 registers the port number to be used in the remote port registration unit 302. Registration is
This is realized by transmitting a packet including a port number and a server address as shown in FIG. The remote port registration unit 302 manages servers and their port numbers in a remote port management table as shown in FIG. By registering a plurality of remote port management tables with a set of a port number and a server address, a plurality of servers can be registered.

When the client sends a request packet to the server, the request packet is sent to the global address of the gateway device. At this time, the port number is the port number used by the server.

The request packet has a global address I /
The processing reaches the port comparison unit 202 through F106. If the port number of the request packet is a port number not registered in the port registration unit 201, the port comparison unit 202 passes the request packet to the address conversion unit 303. Otherwise, it is passed to the communication protocol unit 112.

The address conversion unit 303 retrieves the port number of the request packet from the one registered in the remote port registration unit 302, converts the address of the request packet into a private address of the corresponding server, and converts the address of the request packet into a private address I / F. Through to the corresponding server.

As described above, the server registers the port number to be used in the remote port registration unit, and the address translation unit translates the address in accordance with the port number of the request packet. To the request packet.

[0045]

As is apparent from the above description, according to the gateway apparatus of the present invention, a client registers a global address for accessing a server, and transmits and receives packets to and from a global address network and a private address network. Perform
The address of the received packet is compared with the registered address, and if they are the same, the packet is converted to the registered address and transmitted.

Therefore, by registering the address of the server in advance and converting the address of the request packet, it becomes possible to transmit the packet from the client on the global address network to the server on the private address network.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a gateway device according to Embodiment 1 of the present invention.

FIG. 2 is a block diagram showing a configuration of a gateway device according to a second embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a gateway device according to a third embodiment of the present invention.

FIG. 4 shows a remote port registration packet format according to the third embodiment of the present invention.

FIG. 5 is a configuration example of a remote port management table according to the third embodiment of the present invention.

[Explanation of symbols]

 101 client 102 global address network 103 server 104 private address network 105, 205, 305 gateway device 106 global address I / F 107 private address I / F 108 private address registration unit 109 through address registration unit 110 address comparison unit 111 address conversion unit 112 Communication protocol unit 201 Port registration unit 202 Port comparison unit 301 Server 302 Remote port registration unit 303 Address conversion unit

Claims (6)

[Claims] A private address registration unit for registering an address of the server having a private address, the gateway device being connected to each of a global address network connected to a client and a private address network connected to a server; A through address registration unit for registering a global address for the client to access the server; a global address I / F for transmitting and receiving packets to and from the global address network; and a private address for transmitting and receiving packets to and from the private address network The I / F compares the address of the received packet with the address registered in the through address registration unit, and if the addresses are the same, the address transmitted to the address conversion unit. A comparison unit, and an address conversion unit that converts an address of the received packet into an address registered by the private address registration unit and transmits the address to the private address I / F. Gateway device. 2. The gateway device according to claim 1, wherein a request packet from a client on the global address network can be transferred to a server on the private network registered in advance. 3. A private address registration unit for registering an address of a server having a private address, the gateway unit being connected to each of a global address network connected to a client and a private address network connected to a server. A global address I / F for transmitting and receiving packets to and from a global address network; a private address I / F for transmitting and receiving packets to and from the private address network; and a port registration unit for registering a port number used by the gateway device. It is checked whether the port number of the packet received from the global address I / F is included in the port number registered with the port registration unit. A port comparison unit that sends the packet to the translation unit; and an address translation unit that translates the address of the received packet into an address registered in the private address registration unit and transmits the address to the private address I / F. A gateway device characterized by being performed. 4. The gateway device according to claim 3, wherein a request packet addressed to a port number not used by the gateway device can be transferred to the server. 5. A private address registration unit for registering an address of the server having a private address, the gateway device being connected to each of a global address network connected to a client and a private address network connected to a server. A global address I / F for transmitting and receiving packets to and from the global address network; a private address I / F for transmitting and receiving packets to and from the private address network; and a port registration unit for registering a port number used by the gateway device. A port used by the server and a remote port registration unit for registering a private address; and a port number of a packet received from the global address I / F is registered in the port. If the port number is not included in the port number registered in the recording unit but is included in the port number registered in the remote port registration unit, the port comparison unit that sends the packet to the address conversion unit; A gateway for converting the address registered by the port registration unit and transmitting the address to the private address I / F. 6. The gateway device according to claim 5, wherein a port number of the request packet received from the client is checked, and transfer is possible to a server waiting at the port number.