JP3509848B2 - Communication control device and recording medium - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device used for communication between a client device on a global network and a server device on a local area, and a recording medium recording a program therefor.

[0002]

2. Description of the Related Art Conventionally, an NA for mediating communication between a device on a local area and a device on a global net.
A T (Network Address transfer) technique is known. As an example of this, for example, JP-A-11-150566.
An internetwork device described in the publication is cited.
Certainly, according to this device, a client device on the local network can automatically establish a connection with a server device on the global network. The reason is that the IP address and its port number on the global network are publicly available.

On the other hand, when the client device on the global network establishes a connection with the server device on the local network, the IP address and its port number on the local network are disclosed. Since this is not done, it cannot always be done automatically, and the technical disclosure for this is not made in the above publication.

The present invention has been made to solve such a conventional problem, and a client device on a global network automatically establishes a connection with a server device on a local network for communication. An object of the present invention is to provide a communication control device that enables the above and a recording medium recording a program therefor.

In order to achieve the above object, the present invention relates to a device used for communication between a client device on a global network and a server device on a local area, wherein a predetermined device is used from the client device. Before the processing request is issued, in response to the instruction from the server device, the local address of the server device and the port number in the local address are converted into the global address and the port number in the global address. Is stored in association with the local address and the port number in the local address, and when the predetermined processing request from the client device is received, the global address sent and the port in the global address are sent. The number is the information that has been accumulated With reference to the local address and the means for converting the port number in the local address, and the server device, when the predetermined processing is completed, the local address of the server device and the port number in the local address, With reference to the accumulated information, a means for converting a global address and a port number in this global address, and the server
Bar device local address and this local address
Port number in the device and the global address
And the port number in this global address
Is stored in association with the predetermined processing identifier.
And so on.

According to the present invention, before the predetermined processing request is issued from the client device, in other words, before the connection is established, in response to the instruction from the server device, the local address of the server device and this local address are sent. The port number in is converted into the global address and the port number in the global address, and the local address and the port number in the local address are associated and accumulated. Therefore, the subsequent conversion of addresses and port numbers between local and global can be performed automatically. In other words, the connection can be automatically established even for the server device to which the private local address or port number is set. Also, the server device
Local network and global network
Address and port number on both networks
On the local network and on the global network
It is possible to communicate with both devices on the work.
It

[0005]

[0006]

Further, in a computer-readable recording medium in which a program for controlling communication in communication between a client device on a global network and a server device on a local area is recorded, a predetermined processing request is issued from the client device. Before being issued
In response to an instruction from the server device, the local address of the server device and the port number in the local address are converted into a global address and a port number in the global address, and the local address and the local address are converted. Processing for accumulating in association with the port number in the internal address, and when the predetermined processing request from the client device is received, the global address sent and the port number in this global address are accumulated. See the information that
The process of converting the local address and the port number in the local address, and the local address of the server device and the port number in the local address when the server device completes the predetermined process are stored. Referring to have information, the process of converting to the port number of the global address and within the global address, local address of the server device and
Translates these port numbers in this local address
Global address and this global address
The port number in the above is associated with the identifier of the predetermined process.
There is also provided a recording medium in which a program for executing the processing including the processing for storing the information and the processing for storing the information is recorded.

Incidentally, as such a recording medium, RO
M, semiconductor recording medium such as semiconductor IC, DVDROM, C
Examples thereof include an optical recording medium such as DROM, a magnetic recording medium such as a flexible disk, and a magneto-optical recording medium such as MO.

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of a communication system including a communication control device 1 according to an embodiment of the present invention. The communication control device 1 is connected to a global network 2 whose address and its port number are open to the public, and a local network 3 whose address and its port number are normally closed. A client device 4 that requests execution of a predetermined process is connected to the global network 2, while a server device 5 that executes a requested process and responds to a service is connected to the local network 3.

Communication controller 1 having a gateway function
Has a service management device 11 and an address translation device 12. The service management device 11 includes a service name / service identifier registration means 111, a service identifier analysis means 112, a local address notification means 113, a global address reception means 114, a global service identifier creation means 115, and a service name / service identifier. And a storage device 116.

The address translation device 12 also comprises an instruction relay means 121, an address translation means 122, a local address reception means 123, a global address creation means 124, and an address storage device 125.

Service name / service identifier registration means 11
1 is from the server device 5 on the local network,
Before a request for a predetermined process is issued from the client device 4, a registration request for a service name and a service identifier of the process is received. The service identifier is composed of a header part and a data part as shown in FIG. 3, and the header part includes an IP address and a port number. The service identifier analysis unit 112 analyzes the service identifier notified by the service name / service identifier registration unit 111, and extracts the IP address and port number of the local network from the service identifier.

The local address notifying means 113 notifies the address translator 12 of the IP address and port number of the local network. The global address receiving means 114 receives the IP address and port number of the global network from the address translation device 12. The global service identifier creating means 115 replaces the IP address and port number of the local network in the service identifier with the IP address and port number of the global network. The service name / service identifier storage device 116 stores the service name and the service identifier in association with each other.

The command relay unit 121 requests / services a service between the global network and the local network.
Relay the response. The address translation unit 122 translates the address of the IP packet relayed by the address translation device 12. The local address receiving means 123 receives the IP address and port number of the local network from the service management device 11. Global address creating means 12
4 creates and assigns a unique global network IP address and port number to the local network IP address and port number. The address storage device 125 uses the port number of the global network,
The IP address and the port number of the local network are stored in association with each other.

Next, the operation will be described. The IP address of the communication control device 1 itself on the global network is "X" (set in the address translation device 12).
As described below. First, in response to a command from the server device 5, the communication control device 1 activates the service name / service identifier registration means 111 before the client device 4 issues a request for a predetermined process. The service name / service identifier registration means 111 passes the service name and service identifier to the global service identifier creation means 115, and also passes the service identifier to the service identifier analysis means 112. The service identifier analyzing means 112 passes the IP address and the port number on the local network of the server device 5 obtained by analyzing the service identifier to the local address notifying means 113.

The local address notifying means 113 delivers the IP address and port number received from the service identifier analyzing means 112 to the local address receiving means 123 of the address translation device 12. The local address receiving means 123 delivers the IP address and the port number received from the local address notifying means 113 to the global address creating means 124.

The global address creating means 124 interprets the IP address and port number received from the local address receiving means 123 as an address on the local network, and whether the same local address is registered in the address storage device 125. Check whether or not.
If they are not the same, global address creating means 1
24 gives a unique search number (port number in the global address) to the IP address and port number of the local network, and stores them in the address storage device 125 in association with each other.

FIG. 4 is an explanatory diagram of an example of the storage state of the address storage device 125. According to this example, the global address creating means 124 has a unique search number (port number in the global address) "Y" in the IP addresses and port numbers "a" and "b" of the local network. The address storage device 1
It is stored in 25.

Further, global address creating means 124
If there is a match with the local address registered in the address storage device 125, the retrieval number assigned to the local address is retrieved. The global address creating means 124 uses the search number as the port number for the global network (“Y” in FIG. 4).
And The global address creating means 124 notifies the global address receiving means 114 of a combination of the IP address “X” of the address translation device 12 and the port number “Y”.

The global address receiving means 114 delivers the IP address and port number on the local network notified by the global address creating means 124 to the global service identifier creating means 115. The global service identifier creating means 115 receives the IP address and the port number of the server device 5 on the local network notified from the service name / service identifier registering means 111 from the global address receiving means 114. And port number.

Global service identifier creating means 115
Stores the service identifier in which the IP address and the port number are rewritten in the service name / service identifier storage device 116 together with the service name received from the service name / service identifier registration means 111. FIG. 5 is an explanatory diagram showing this storage example, in which the service name “process”, the global address “X”, and the port number “Y” in the global address are stored in association with each other.

Next, the operation when the client device 4 actually issues a request to execute a predetermined process will be described. Client device 4 on the global network
Makes a service request, the service request is relayed by the address translation device 12. Command relay means 1
21 receives the service request and requests the address conversion means 122 to perform address conversion of the service request. The address conversion unit 122 searches the address storage device 125 for an address for the local network using the destination port number of the service request as a key. Then, the address translation unit 122 translates the destination IP address and the port number of the service request into the addresses for the local network that are matched by the search. Specifically, if the service request from the client device 4 includes the information of the global address “X” and the port number “Y”, as shown in FIG. The port number "b" in the local address.

The command relay means 121 sends the service request converted into the address for the local network to the local network 3. When the server device 5 on the local network 3 finishes the process and makes a service response, the service response is relayed by the address translation device 12. Command relay means 121
Receives the service response and requests the address translation means 122 to translate the source address of the service response.
The address conversion means 122 uses the source IP address and port number of the service response as keys to store the address storage device 1.
The port number for the global network is searched from 25. The address conversion unit 122 converts the port number for the global network that matches the search and the IP address of the address conversion device 12 into the IP address and the port number of the transmission source, and transmits the converted IP address to the global network.
Specifically, if the service response from the server device 5 includes the information of the local address "a" and the port number "b", as shown in FIG. 4, this is changed to the global address "X" and the global address. The information is transmitted to the global network 2 as the port number “X” in the above.

Therefore, according to this embodiment, the server device 5 responds to the instruction from the server device 5 before the predetermined processing request is issued from the client device 4, in other words, before the connection is established. 5 local address and port number in this local address,
The global address and the port number in the global address are stored in the address storage device 125 in association with the local address and the port number in the local address. Therefore, the subsequent conversion of addresses and port numbers between local and global can be performed automatically. In other words, the connection can be automatically established even for the server device to which the private local address or port number is set.

Further, as a result, since a unique local address can be specified by using the port number disclosed for the global network as a key, it is not necessary to use a plurality of IP addresses of the global network.

Next, another embodiment will be described. In this embodiment, the global service identifier creating means 115.
Stores the local address and port number from the server device 5 in association with the service name, and also converts these local address and port number into a global address and its port number in association with the service name. It is stored and stored in the service name / service identifier storage device 116. An example of this accumulation is shown in FIG.

Service name / service identifier storage device 11
There are two service identifiers stored in 6 for the global network and the local network. Therefore, when the client device requests the service identifier, the address of the requesting client is determined, and if the request is from within the local network, the service identifier for the local network is used. Returns the service identifier. This allows the client device on the local network to access the server device.

Therefore, according to this other embodiment,
The server device 5 can communicate with both devices on the local network and the global network by using addresses and port numbers on both the local network 3 and the global network 2.

The apparatus shown in FIG. 2 can be realized by storing a program in which the operating procedure is programmed in a ROM or the like and executing this by the CPU.

Although the embodiments of the present invention have been described above, various modifications and changes can be made to the embodiments of the present invention without departing from the scope of the present invention. There are various modifications and changes such as load balancing as a configuration in which the conversion device 12 and the service management device 11 are arranged in separate devices.

As described above, according to the present invention, in response to an instruction from the server device before a predetermined processing request is issued from the client device, in other words, before the connection is established. , The local address of the server device and the port number in this local address are converted into the global address and the port number in this global address, and are stored in association with the local address and the port number in this local address. Therefore, it is possible to automatically establish a connection even for a server device to which a private local address or port number is set.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a communication system including a communication control device of the present invention.

FIG. 2 is a block configuration diagram of a communication control device according to the embodiment of the present invention.

FIG. 3 is an explanatory diagram of service identifiers.

FIG. 4 is an explanatory diagram of contents stored in an address storage device 125.

FIG. 5 is an explanatory diagram of contents stored in a service name / service identifier storage device 116.

FIG. 6 is an explanatory diagram of another embodiment.

[Explanation of symbols]

1 Communication control device 2 Global network 3 local network 4 Client device 5 Server device 11 Service management device 12 Address translator 111 Service name / service identifier registration means 112 Service Identifier Analyzing Means 113 means for notifying local address 114 Global address receiving means 115 Global Service Identifier Creating Means 116 Service name / service identifier storage device 121 Command relay means 122 address conversion means 123 means for receiving local address 124 Global address creation means 125 address storage device

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-8-263413 (JP, A) JP-A-2000-59416 (JP, A) K. Egevang, et. a. , The IP Network Address Translator (NAT), RFC 1631, USA, IETF, May 1994, p2-3P. Srisuresh, et. a. , Road Sharing using IP Network Addition Translation (LSNAT), RFC 2391, IETF, August 1998, p8-9 (58) Fields investigated (Int.Cl. ⁷ , DB name) H04L 12/66 H04L 12 / 28 H04L 29/08

Claims (2)

(57) [Claims] 1. A device used for communication between a client device on a global network and a server device on a local area, wherein an instruction from the server device is given before a predetermined processing request is issued from the client device. In response, the local address of the server device and the port number within this local address are converted into a global address and a port number within this global address,
Means for storing the local address in association with the port number in the local address; and, when receiving the predetermined processing request from the client device, the global address sent and the port number in the global address. With reference to the accumulated information, a means for converting the local address and a port number in the local address, and when the server device completes the predetermined processing, the local address of the server device and the local address A means for converting a port number in a local address into a global address and a port number in the global address by referring to the accumulated information, and a local address of the server device and this local device.
Port numbers in the global address, the translated global address and this glow
The port number in the global address is used to identify the specified process.
Characterized by comprising a means for storing in association with the Besshi, the
A communication control device to. 2. A client on a global network
Communication between the server device and the server device in the local area.
A computer that records a program for controlling communication in
In a computer-readable recording medium , the client device issues a predetermined processing request.
Before responding to the instruction from the server device,
Server device local address and this local address
Port number within the global address and this
Converted to the port number in the global address,
The local address and the port within this local address
A process of storing the data in association with a client number and receiving the predetermined process request from the client device.
If you do, the global address sent to you and this
The port number in the global address and the
Refer to the information you provided to find the local address and this
If the server device completes the process of converting to the port number in the local address and the predetermined process,
Server device local address and this local address
For the port number in the reply, refer to the information accumulated above
The global address and this global address.
Conversion to the port number in the server, the local address of the server device and this local
Port numbers in the global address, the translated global address and this glow
The port number in the global address is used to identify the specified process.
A process that includes the process of associating with another child and storing
A recording medium on which a program for recording is recorded .