JP4074623B2 - Data transmission relay system and data transmission relay method - Google Patents

Description

  In particular, the present invention relates to a data transmission relay system and a data transmission relay method used for connecting terminals belonging to different communication networks via a telephone network.

Terminals belonging to different communication networks are connected to each other, and the terminals belonging to one communication network, for example, perform remote diagnosis and remote monitoring of terminals belonging to the other communication network via a public communication network such as a telephone network. Technology is required. Conventionally, as a technique for connecting terminals belonging to different communication networks as described above, there is one disclosed in Japanese Patent Laid-Open No. 2003-224580. The network system described in this publication is a system for allowing a connection destination terminal belonging to a private communication network to connect from a connection source terminal outside the private communication network via the Internet network. This system includes a network address translation device at the boundary between a private communication network using a private address and an Internet network using a global address. By this device, a private address and a global address of destination information stored in an IP packet are provided. Are mutually converted to enable data transmission between different IP networks.
JP 2003-224580 A

  However, since this type of private communication network employs a unique IP address system and is individually operated, there may be cases where duplicate network addresses are used in each private communication network. If you want to connect to multiple private networks that do not guarantee uniqueness of such network addresses, you cannot specify the connection destinations centrally. The connection could not be established smoothly and smooth data transmission could not be performed.

  Therefore, an object of the present invention is to provide a data transmission relay system and a data transmission relay method that enable smooth data transmission to a plurality of different communication networks.

  The data transmission relay system according to the present invention includes a first terminal belonging to a first communication network and a second terminal belonging to each of a plurality of second communication networks different from the first communication network. Is a data transmission relay system that connects via a network and relays data transmission between a first terminal and a second terminal, the first transmission existing at the boundary between the first communication network and the telephone network And a plurality of second transmission devices respectively present at the boundary between each second communication network and the telephone network, and the first transmission device is a virtual allocated to each second transmission device. A telephone number table storage means for storing a telephone number table in which a transmission apparatus address and a telephone number in the telephone network of the second transmission apparatus are associated with each other, and transmission data received from the first terminal and included in the transmission data Based on the virtual address of the destination Address calculating means for calculating the virtual transmission device address of the second transmission device that relays the transmission data, and a second relay device that relays the transmission data by referring to the telephone number table based on the calculated virtual transmission device address. A connection between the telephone number selection means for selecting the telephone number of the transmission apparatus and the second transmission apparatus that relays transmission data based on the selected telephone number is established via the telephone network, and the transmission data is A first data transfer means for transferring to the second transmission device, and the second transmission device existing between the second communication network and the telephone network is the second data belonging to the second communication network. Address table storage means for storing an address table in which the virtual address of the second terminal and the local address of the second terminal in the second communication network are associated with each other, and transmission from the first data transfer means An address for selecting the local address of the second terminal, which is the destination terminal, by referring to the address table based on the data receiving means for receiving the data and the virtual address of the destination terminal included in the received transmission data It has a selection means and a second data transfer means for transferring transmission data to a second terminal corresponding to the local address based on the selected local address.

  The data transmission relay method according to the present invention includes a first terminal belonging to the first communication network and a second terminal belonging to each of a plurality of second communication networks different from the first communication network. A data transmission relay method for connecting data via a telephone network and relaying data transmission between a first terminal and a second terminal, wherein the first transmission network exists at the boundary between the first communication network and the telephone network. Each of the transmission devices has a virtual transmission device address assigned to a plurality of second transmission devices existing at the boundary between each second communication network and the telephone network, and a telephone number in the telephone network of the second transmission device. Is stored in the telephone number table, and the transmission data from the first terminal is received, and the transmission data is relayed based on the virtual address of the transmission destination terminal included in the transmission data. Calculate the virtual transmission device address of the transmission device Based on the received virtual transmission apparatus address, the telephone number table is referred to, the telephone number of the second transmission apparatus that relays transmission data is selected, and the transmission data is relayed based on the selected telephone number. A connection with the second transmission device is established via the telephone network, the transmission data is transferred to the second transmission device, and the second transmission device is connected to the second terminal belonging to the second communication network. Stores an address table in which a virtual address and a local address of a second terminal in the second communication network are associated with each other, receives transmission data from the first transmission device, and receives the received transmission data The address table is referenced based on the virtual address of the destination terminal included in the destination terminal, the local address of the second terminal that is the destination terminal is selected, and based on the selected local address, Characterized by transferring the transmit data to the second terminal corresponding to the local address.

  In the data transmission relay system and the data transmission relay method, the first transmission device that receives the transmission data from the first terminal has the virtual transmission device address allocated to each second transmission device and the second transmission device. Stores a telephone number table associated with telephone numbers. The first transmission device receives the transmission data from the first terminal, and based on the virtual address of the destination terminal included in the transmission data, the first transmission device relays the transmission data. Calculate the transmission device address. Then, a telephone number corresponding to the calculated virtual transmission apparatus address is selected from the telephone number table, a connection with the second transmission apparatus is established based on the telephone number, and the transmission to the second transmission apparatus is performed. Transfer data. The second transmission device that receives the transmitted transmission data stores an address table in which the virtual address of the second terminal and the local address of the second terminal are associated with each other. The second transmission apparatus selects a local address corresponding to the virtual address of the destination terminal included in the received transmission data, and transfers the transmission data to the second terminal corresponding to the local address. As described above, according to the data transmission relay system and the data transmission relay method, the second terminal belonging to each second communication network can be centrally designated as the connection destination using the virtual address. . Therefore, it is possible to smoothly establish a connection from the first terminal to the first communication network and the second communication network, and smooth data transmission between the first terminal and each second terminal. Is possible.

  According to the data transmission relay system and data transmission relay method of the present invention, smooth data transmission to a plurality of different communication networks becomes possible.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of a data transmission relay system according to the present invention will be described in detail with reference to the drawings.

  In the communication network group to which the data transmission relay system 1 shown in FIG. 1 is applied, a plurality of personal computers 3p belong to the in-house LAN (first communication network) 3 of company Z, and the in-house LAN (first 2 communication network 5, company B's internal LAN (second communication network) 7, and company C's internal LAN (second communication network) 9, respectively, a plurality of personal computers 5p and a plurality of network printers 50a. Etc belong. The data transmission relay system 1 is configured such that a personal computer (first terminal) 3p belonging to the in-house LAN 3 of company Z, a network printer (second terminal) belonging to the in-house LAN 5 of company A, the in-house LAN 7 of company B, and the in-house LAN 9 of company C. Terminal) 50a and the like are remotely accessed via the mobile phone network 11. For example, when the printer manufacturer Z performs remote diagnosis and remote monitoring of a printer manufactured by company Z that is used as a network printer in company A, company B and company C, such a data transmission relay system 1 Is useful.

  The data transmission relay system 1 includes a connection-side data transmission device (first transmission device) 31 that exists at the boundary between the in-house LAN 3 and the mobile phone network 11, and a connection that exists at the boundary between the in-house LAN 5 and the mobile phone network 11. A data transmission device (second transmission device) 51 on the front side, a data transmission device (second transmission device) 71 on the connection side existing at the boundary between the in-house LAN 7 and the mobile phone network 11, and the in-house LAN 9 and the mobile phone A data transmission device (second transmission device) 91 on the connection destination side existing at the boundary with the network 11 is provided. Each of the data transmission devices 51, 71, 91 on the connection destination side is assigned a mobile phone number for identifying the data transmission device in the mobile phone network 11, and is connected to the connection source via the mobile phone line. It is possible to establish a connection between the data transmission device 31 on the side and the data transmission devices 51, 71, 91 of the connection source.

  A unique local address in the in-house LAN 3 is assigned to each personal computer 3p connected to the in-house LAN 3, and the in-house LAN 3 is operated using this local address system. For example, each personal computer 3p can transmit data to any other desired personal computer by designating each other's local address under the environment of the in-house LAN 3. The in-house LAN 3 is connected to the mobile phone network 11 via the data transmission device 31 described above.

  A unique local address in the in-house LAN 5 is assigned to each of the personal computer 5p and the network printers 50a, 50b, 50c connected to the in-house LAN 5, and the in-house LAN 5 is operated using this local address system. For example, in the environment of the in-house LAN 5, each personal computer 5p designates a local address assigned to the network printer 50a, 50b, 50c, and transmits data to any desired network printer. Can be printed out. Here, the local address of the printer 50a (192.168.10.1), the local address of the printer 50b (192.168.10.2), and the local address of the printer 50c (192.168.10.3) (See FIG. 3). The in-house LAN 5 is connected to the cellular phone network 11 via the data transmission device 51 described above.

  A plurality of personal computers 7p and three network printers 70a, 70b, 70c are connected to the in-house LAN 7, and are configured and operated in the same manner as the in-house LAN 5 described above. The in-house LAN 7 is connected to the mobile phone network 11 via the data transmission device 71 described above. In addition, a plurality of personal computers 9p and three network printers 90a, 90b, 90c are connected to the in-house LAN 9, which is configured in the same manner as the in-house LAN 5 described above and is operated in the same manner as the in-house LAN 5. . The in-house LAN 9 is connected to the mobile phone network 11 via the data transmission device 91 described above.

  The in-house LANs 3, 5, 7, and 9 are individually operated by the company Z, the company A, the company B, and the company C. The in-house LANs 3, 5, 7, and 9 have their own local addresses. The system is adopted. For this reason, the local addresses assigned to the personal computers and the printers may be duplicated in the entire in-house LANs 3, 5, 7, and 9. Therefore, when it is desired to perform remote diagnosis of any network printer belonging to any of the in-house LANs 5, 7 and 9 from the personal computer 3p belonging to the in-house LAN 3, even if an attempt is made to connect using these local addresses. The destination cannot be specified centrally. Thus, in order to achieve smooth connection to a network printer in which the uniqueness of the address system over a plurality of communication networks is not guaranteed, the data transmission relay system 1 includes a data transmission device 31 and data transmission devices 51, 71, 91 is provided.

  The data transmission device 31 will be described. The data transmission device 31 includes, as functional components, an address calculation unit (address calculation unit) 33, a telephone number selection unit (phone number calculation unit) 35, a data communication unit (first data transfer unit) 37, and a telephone number. A table storage unit (telephone number table storage means) 39 is provided. As shown in FIG. 2, the telephone number table storage unit 39 associates the virtual transmission device addresses of the data transmission devices 51, 71, 91 with the mobile phone numbers of these data transmission devices 51, 71, 91. A telephone number table 39a is stored.

  Here, the virtual transmission apparatus address is an address virtually allocated to the data transmission apparatuses 51, 71, 91 as connection destinations from the in-house LAN 3. In the data transmission relay system 1, the virtual transmission device address of the data transmission device 51 (192.68.1.0/24) and the virtual transmission device address of the data transmission device 71 (192.68.2.0/24) (192.68.3.0/24) is assigned as the virtual transmission device address of the data transmission device 91. This virtual transmission device address is composed of 32 bits, and the lower 8 bits of the 32 bits are set to “0”. Each virtual transmission device address is set so as not to overlap with an address assigned to another device belonging to the in-house LAN 5.

  The address calculation unit 33 receives a packet (transmission data) transmitted from the personal computer 3p to be connected to the network printer 50a or the like, and acquires a virtual address of the destination printer included in the packet. Then, based on the acquired virtual address, a data transmission apparatus that relays transmission of this packet (that is, a data transmission apparatus that exists at the boundary between the internal LAN to which the printer that is the transmission destination of this packet belongs and the cellular phone network 11) ) Is calculated.

  Here, the virtual address is an address virtually allocated to each network printer 50a, 50b, 50c, 70a, 70b, 70c, 90a, 90b, 90c belonging to each in-house LAN. This virtual address is composed of 32 bits, and the upper 24 bits are set to match the virtual transmission device address of the data transmission device existing at the boundary between the in-house LAN to which the printer belongs and the mobile phone network 11. The For example, here, the virtual address of the printer 50a (192.168.1.1), the virtual address of the printer 50b (192.168.1.2), and the virtual address of the printer 50c (192.168.8.1. 3) is allocated (see FIG. 3).

  The telephone number selection unit 35 refers to the telephone number table 39a stored in the telephone number table storage unit 39 based on the virtual transmission device address calculated by the address calculation unit 33, and carries the mobile phone corresponding to the virtual transmission device address. Select a phone number.

  The data communication unit 37 establishes a connection with any of the data transmission devices 51, 71, 91 corresponding to the mobile phone number via the mobile phone network 11 based on the mobile phone number selected by the phone number selection unit 35. In this way, the data transmission device 31 and any one of the data transmission devices 51, 71, 91 are connected by the mobile phone line. And the data communication part 37 transfers the packet from the personal computer 3p to said data transmission apparatus with which the connection was established.

  Next, the data transmission device 51 will be described. The data transmission device 51 includes a data communication unit (data receiving unit) 53, an address selection unit (address selection unit) 55, a data transfer unit (second data transfer unit) 57, and an address table storage unit (address table storage unit). 59. As shown in FIG. 3, the address table storage unit 59 associates the virtual addresses of the network printers 50a, 50b, and 50c belonging to the company LAN 5 with the local addresses of these network printers in the company LAN 5. Is stored.

  The data communication unit 53 is a part that receives a packet from the data transmission device 31 described above. Then, the address selection unit 55 acquires the virtual address of the destination printer included in the packet, refers to the address table 59a, and selects a local address corresponding to the virtual address. The data transfer unit 57 transfers the packet to the network printer corresponding to the local address selected by the address selection unit 55.

  The data transmission device 71 includes a data communication unit 73, an address selection unit 75, a data transfer unit 77, and an address table storage unit 79. The data transmission device 91 includes a data communication unit 93, an address selection unit 95, a data transfer. Unit 97 and an address table storage unit 99. Since the data transmission devices 71 and 91 are configured in the same manner as the data transmission device 51, description thereof is omitted.

  In the data transmission relay system 1 as described above, the personal computer 3p belonging to the in-house LAN 3 to any one of the network printers 50a belonging to any of the in-house LANs 5, 7, 9 (in the following example, the network printer 50b belonging to the in-house LAN 5). Will be described.

  First, as shown in FIG. 4, the personal computer 3p includes a virtual address (192.168.1.2) assigned to the network printer 50b belonging to the in-house LAN 9 of company C as a destination address in the packet. Is transmitted (step S402). This packet is received by the data transmission device 31, and the address calculation unit 33 adds 8 bits indicating “0” after the upper 24 bits (192.168.1. 1) of the virtual address included in the packet, and The virtual transmission device address of the data transmission device as the transmission destination is calculated (step S404). Here, (192.168.1.0/24) is calculated as the virtual transmission device address, and this virtual transmission device address is the link between the in-house LAN 5 and the cellular phone network 11 to which the network printer 50b that is the packet transmission destination belongs. This corresponds to the virtual transmission device address of the data transmission device 51 existing at the boundary.

  The telephone number selection unit 35 refers to the telephone number table 39a (step S406), and the cellular phone number “090-AAAAA-” corresponding to the calculated virtual transmission device address (192.168.1.0/24). “AAAA” is selected (step S408). This mobile phone number corresponds to the mobile phone number of the data transmission device 51. Subsequently, the data communication unit 37 transmits a connection signal based on the selected mobile phone number “090-AAAAA-AAAA” (step S410). In this way, the connection by the TCP / IP between the data transmission device 31 and the data transmission device 51 (that is, the in-house LAN 3 and the in-house LAN 5) is established via the mobile phone network 11 (step S412). And the data communication part 37 transmits said packet toward the data transmission apparatus 51 by which the connection was established (step S414).

  The data communication unit 53 of the data transmission apparatus 51 receives the above packet via the mobile phone network 11. The address selection unit 55 acquires the virtual address (192.168.1.2) of the destination printer included in this packet, refers to the address table 59a (step S414), and selects the local address corresponding to this virtual address. The address (192.168.10.2) is selected (step S418). This local address corresponds to a local address assigned to the network printer 50b in the in-house LAN 5. Then, the data transfer unit 57 rewrites the virtual address of the transmission destination included in this packet with the selected local address (192.168.10.2). Then, the data transfer unit 57 transmits this packet to the network printer 50b corresponding to the local address in the in-house LAN 5 (step S420), and the network printer 50b receives this packet. Through the above processing, transmission of packet data from the personal computer 3p to the network printer 50b is relayed.

  According to the data transmission relay system 1 and the data transmission relay method described above, the personal computer 3p belonging to the in-house LAN 3 uses the virtual address of the network printer 50a and the like as the local address in the in-house LAN 3 without being aware of the mobile phone network 11. Can be handled. In addition, even in the case where there is an overlap in the local address allocated to each network printer 70a or the like in each of the in-house LANs 5, 7, and 9, the destination printer can be designated centrally using this virtual address. Can do. Therefore, the personal computer 3p can establish a smooth connection via the mobile phone network 11 to the network printers 50a, 70a, 90a, etc. belonging to the in-house LANs 5, 7, 9 which are different communication networks.

It is a block diagram which shows one Embodiment of the data transmission relay system which concerns on this invention. It is a figure which shows an example of a telephone number table. It is a figure which shows an example of an address table. It is a sequence diagram which shows the process for connecting with the network printer of another communication network from a personal computer, and transmitting a packet.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Data transmission relay system, 3 ... In-house LAN (1st communication network), 3p ... Personal computer (1st terminal), 5, 7, 9 ... In-house LAN (2nd communication network), 50a, 50b, 50c , 70a, 70b, 70c, 90a, 90b, 90c... Network printer (second terminal), 11... Cellular phone network, 31... Data transmission device (first transmission device), 33. , 35... Telephone number selection section (phone number selection means), 37... Data communication section (first data transfer means), 39 a... Telephone number table, 39... Telephone number table storage section (phone number table storage means) 51, 71, 91 ... Data transmission device (second transmission device), 53, 73, 93 ... Data communication unit (data receiving means), 55, 75, 95 ... Address selection unit (address selection means), 5 , 77,97 ... data transfer unit (second data transfer means), 59a, 79a, 99a ... address table, 59,79,99 ... address table storage section (address table storage means).

Claims (2)

A first terminal belonging to a first communication network and a second terminal belonging to each of a plurality of second communication networks different from the first communication network are connected via a telephone network, and the first terminal A data transmission relay system for relaying data transmission between the second terminal and the second terminal,
A first transmission device existing at a boundary between the first communication network and the telephone network;
A plurality of second transmission devices respectively present at the boundary between each of the second communication networks and the telephone network;
The first transmission device includes:
Telephone number table storage means for storing a telephone number table in which a virtual transmission device address allocated to each second transmission device and a telephone number of the second transmission device in the telephone network are associated with each other;
Address calculation means for receiving transmission data from the first terminal and calculating a virtual transmission device address of the second transmission device that relays the transmission data based on a virtual address of a transmission destination terminal included in the transmission data When,
Based on the calculated virtual transmission device address, telephone number selection means for referring to the telephone number table and selecting the telephone number of the second transmission device that relays the transmission data;
Based on the selected telephone number, a connection is established with the second transmission device that relays the transmission data via the telephone network, and the transmission data is transferred to the second transmission device. Data transfer means, and
The second transmission device existing between the second communication network and the telephone network is:
Address table storage means for storing an address table in which the virtual address of the second terminal belonging to the second communication network is associated with the local address of the second terminal in the second communication network; ,
Data receiving means for receiving the transmission data from the first data transfer means;
Address selection means for referring to the address table based on the virtual address of the destination terminal included in the received transmission data and selecting the local address of the second terminal that is the destination terminal;
And a second data transfer means for transferring the transmission data to the second terminal corresponding to the local address based on the selected local address. A first terminal belonging to a first communication network and a second terminal belonging to each of a plurality of second communication networks different from the first communication network are connected via a telephone network, and the first terminal A data transmission relay method for relaying data transmission between the second terminal and the second terminal,
A first transmission device existing at a boundary between the first communication network and the telephone network;
A virtual transmission device address assigned to each of a plurality of second transmission devices existing at a boundary between each of the second communication networks and the telephone network, and a telephone number of the second transmission device in the telephone network; , Stores the phone number table associated with
Receiving transmission data from the first terminal, and calculating a virtual transmission device address of the second transmission device that relays the transmission data based on a virtual address of a transmission destination terminal included in the transmission data;
Based on the calculated virtual transmission device address, refer to the telephone number table, select the telephone number of the second transmission device that relays the transmission data,
Establishing a connection with the second transmission device that relays the transmission data based on the selected telephone number via the telephone network, transferring the transmission data to the second transmission device,
The second transmission device is
Storing an address table in which the virtual address of the second terminal belonging to the second communication network is associated with the local address of the second terminal in the second communication network;
Receiving the transmission data from the first transmission device;
Based on the virtual address of the destination terminal included in the received transmission data, refer to the address table, select the local address of the second terminal that is the destination terminal,
A data transfer relay method, wherein the transmission data is transferred to the second terminal corresponding to the local address based on the selected local address.

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