JPH1051499A - Satellite channel connection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a satellite channel connection device in which communication with a server equipment is attained for a terminal equipment by using one channel for a public network and the satellite channel. SOLUTION: A terminal connection section 32 sends an information request signal sent from a terminal equipment 1 to a protocol conversion section 38. The protocol conversion section 38 converts the communication protocol of a data link layer of the information request signal from the communication protocol of a terminal equipment 1 into a communication protocol of a public network and sends the protocol to a public network connection section 36. The public network connection section 36 sends the information request signal to the public network. On the other hand, a satellite channel connection section 40 sends an information signal sent from a receiver 8 of the satellite channel to the protocol conversion section 38. The protocol conversion section 38 converts the communication protocol of the data link layer of the information signal from the communication protocol of the satellite channel into the communication protocol of the terminal equipment 1 and sends it to the terminal connection section 32. The terminal connection section 32 sends the information signal to the terminal equipment 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a satellite line connection device used in a communication system in which a server device storing information and a terminal requesting the information are connected via a public network and a satellite line. is there.

[0002]

2. Description of the Related Art FIG. 4 is a block diagram showing a configuration example of a communication system using a satellite line connection device according to the prior art. In this figure, reference numeral 2 denotes a server device storing information,
1 is a terminal for extracting information of the server device 2, and 10 is a terminal 1.
The external input / output unit 3 is provided with a public network connection server 3 for receiving a connection via the public network from the terminal 1 and terminating the protocol C of the data link layer of the public network, a router 5, a router 4, and a public network and the terminal 1 , A transmitting device for converting the protocol of the server device 2 into protocol B and transmitting the protocol B to the satellite line, and a satellite line connecting device 6 for terminating the protocol B and connected to the terminal 1.

The terminal 1 and the server device 2 use UDP or TCP for the transport layer and I / O for the network layer.
Communication is performed using P. The protocol of the data link layer is the protocol B (for example, ATM) in the section of the satellite line from the transmission device 7 to the satellite line connection device 6.
The protocol of the data link layer is the protocol C (for example, PPP) in the section of the public network from the public network connection server 3 to the terminal 1 via the modem 4. The protocol of the data link layer is Protocol A (for example, Ethernet) in the section between the satellite line connection device 6 and the terminal 1 and in the section between the public network connection server 3 and the transmission device 7 and the server device 2.

In the system shown in FIG. 4, when the terminal 1 retrieves information of the server device 2, the terminal 1 transmits an information request signal to the server device 2 via a public network. Upon receiving the information request signal from the terminal 1, the server device 2 transmits the information to the terminal 1 via a satellite line. In this system, information transmitted from the server device 2 is transmitted to the terminal 1 using a wideband satellite line. Therefore, when the amount of information is large, the information is transmitted through a narrowband public network. Compared with, there is a feature that the information transfer time is short.

FIG. 5 is a block diagram showing an example of the configuration of a satellite line connection device according to the prior art. The satellite line connection device shown in this figure includes a satellite line connection unit 12, a protocol conversion unit 14, and a terminal connection unit 16. Here, the satellite line connection unit 12 receives the information via the satellite line transmitted from the server device 2 using the protocol B. The protocol conversion unit 14 converts a protocol (protocol B) of the information received by the satellite line connection unit 12 into a protocol A. The terminal connection unit 16 transmits the information converted to the protocol A to the terminal 1
Send to

[0006]

However, the above-mentioned conventional satellite line connection device only processes information via a satellite line, and cannot process information via a public network. Therefore, in the system shown in FIG. 4, the terminal needs to support the protocol of the data link layer for the satellite link section and the public network section,
In addition, there is a disadvantage that it is necessary to provide two external input / output units in order to connect the satellite circuit section and the public network section, respectively. In addition, since the two data link layers are terminated by the same terminal, there is a disadvantage that the processing load on the central processing unit (CPU) of the terminal increases. Further, since the IP address and the address of the data link layer are not associated with each other, a plurality of terminals cannot be connected to the satellite line connection device.

In order to solve the above problems, the present invention enables communication with a server device using a public network and a satellite line by one line without making a terminal aware of a communication path, and It is an object of the present invention to provide a satellite line connection device capable of reducing the communication protocol processing of a terminal.
Another object of the present invention is to provide a satellite line connection device to which a plurality of terminals can be connected by associating an IP address with an address of a data link layer.

[0008]

According to the first aspect of the present invention,
In computer communication performed using UDP / IP and TCP / IP technologies, a server device storing information and a terminal requesting the information are connected via a public network and a satellite line, and information from the terminal to the server device is transmitted. The request signal passes through the public network, the information signal from the server device to the terminal passes through a satellite line, and the satellite line and the public network use a communication protocol different from the data link layer or lower communication protocol used by the terminal. And a satellite line connection device used in a communication system in which the communication protocol of the data link layer of the satellite line and the data link layer of the public network are different, a satellite receiving device receiving a signal of the satellite line, a modem connecting to the public network, and Terminal connection means connected to the terminal for transmitting and receiving signals to and from the terminal, satellite line connection means for receiving a signal from a satellite receiver, Characterized by comprising a public network connection means for transmitting and receiving beam signal, and a protocol conversion means for converting each communication Putorokoru each other. According to a second aspect of the present invention, there is provided a communication system according to the first aspect, wherein
As a communication protocol of a data link layer for transmitting and receiving packets, a public network section uses PPP (point-to-point protocol), and a satellite line section uses a satellite line used for communication using an ATM protocol. Terminal connection means for transmitting and receiving signals to and from the terminal, satellite line connection means for receiving signals from a satellite receiver, public network connection means for transmitting and receiving signals to and from a modem, and ATM filtering means for extracting cells addressed to the terminal from the received ATM cells, and PPP
Protocol conversion means for terminating an IP protocol and an ATM protocol;
Filtering means, wherein the protocol conversion means converts a communication protocol of a data link layer on the terminal side into a PPP of a public network;
It has a function of converting a TM protocol into a data link layer protocol on the terminal side, and further has a function of controlling an output destination of a signal input from each of the connection units. According to a third aspect of the present invention, in the communication system according to the first aspect, there is provided a satellite line connection device used when performing communication using the communication protocol of the data link layer according to the second aspect. Terminal connection means connected to a plurality of terminals by connection, for transmitting and receiving signals to and from the plurality of terminals, satellite line connection means for receiving signals from a satellite receiver, and public network connection means for transmitting and receiving signals to and from a modem ATM filtering means for extracting cells destined for the terminal from ATM cells received via a satellite line;
Protocol conversion means for terminating a P protocol and an ATM protocol; managing destination addresses of the data link layers of the plurality of terminals; extracting only IP packets addressed to the plurality of terminals; Address management means for associating the destination address.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. §1. First Embodiment FIG. 1 is a block diagram showing a configuration example of a satellite channel connection device according to a first embodiment of the present invention. This figure is
This corresponds to claim 1. In this figure, the satellite line connection device comprises a terminal connection unit 32, a satellite line connection unit 40, a public network connection unit 36, and a protocol conversion unit 38, which are connected by an internal bus.

Here, the terminal connection unit 32 transmits and receives information to and from the terminal 1. The satellite line connection unit 40 receives information from the satellite line receiving device 8. Public network connection unit 36
Transmits information to the public network via the modem 4. The protocol converter 38 converts the communication protocol of the data link layer of the terminal 1 into the communication protocol of the data link layer of the public network, and converts the communication protocol of the data link layer of the satellite line into the data of the terminal 1. It has a function of converting to a link layer communication protocol. Further, the protocol conversion unit 38 has a function of controlling an output destination of a signal input from each of the connection units (the terminal connection unit 32, the satellite line connection unit 40, and the public network connection unit 36). Each of the above-described components can be realized by a CPU (Central Processing Unit) that executes software that describes the operations described below, or a communication-specific LSI.

In such a configuration, when an information request signal is transmitted from the terminal 1, the terminal connection unit 32 receives the information request signal and transmits it to the protocol conversion unit 38 via the internal bus. The protocol conversion unit 38 converts the communication protocol of the data link layer of the received information request signal from the communication protocol of the data link layer of the terminal 1 to the communication protocol of the data link layer of the public network, via the internal bus. To the public network connection unit 36. The public network connection unit 36 transmits the received information request signal to the server device 2 via the modem 4 and the public network.

On the other hand, when an information signal is transmitted from the satellite line receiving device 8, the satellite line connection unit 40 receives the information signal and transmits it to the protocol conversion unit 38 via the internal bus. The protocol conversion unit 38 converts the communication protocol of the data link layer of the received information signal from the communication protocol of the data link layer of the satellite link to the communication protocol of the data link layer of the terminal 1 and via the internal bus. , To the terminal connection unit 32. The terminal connection unit 32 transmits the received information signal to the terminal 1 side.

In the case of this embodiment, the terminal 1 supports only a communication protocol between the terminal 1 and the satellite line connection device as a communication protocol of the data link layer, and one terminal between the terminal 1 and the satellite line connection device. Is maintained, communication with the server device 2 is possible without being aware of via a satellite line and a public network.

§2. Second Embodiment FIG. 2 is a block diagram showing a configuration example of a satellite channel connection device according to a second embodiment of the present invention. This figure is
This corresponds to claim 2. In this figure, the satellite line connection device includes a terminal connection unit 52, a satellite line connection unit 60, a public network connection unit 56, an ATM filtering unit 62, an IP filtering unit 63, and a protocol conversion unit 58. The public network connection unit 56, the ATM filtering unit 62, and the protocol conversion unit 58 are connected by an internal bus.

Here, the terminal connection unit 52 transmits and receives information to and from the terminal 1. The satellite line connection unit 60 receives information from the satellite line receiving device 8. Public network connection unit 56
Transmits information to the public network via the modem 4. AT
The M filtering unit 62 receives the A
From the TM cell, the terminal connected to this device (hereinafter, referred to as
A cell addressed to “accommodating terminal”) is taken out. The IP filtering unit 63 holds the IP address of the accommodation terminal and extracts an IP packet addressed to the accommodation terminal. The protocol conversion unit 58 converts a communication protocol of the data link layer on the terminal 1 side into a public network PPP, and
It has a function of converting the ATM protocol of the satellite line into the communication protocol of the data link layer on the terminal 1 side. Further, the protocol conversion unit 58 has a function of controlling an output destination of a signal input from each of the connection units (the terminal connection unit 52, the satellite line connection unit 60, and the public network connection unit 56). Each of the above-described components can be realized by a CPU (Central Processing Unit) that executes software that describes the operations described below, or a communication-specific LSI.

In such a configuration, when an information request signal is transmitted from the terminal 1, the terminal connection unit 52 receives the information request signal and transmits it to the protocol conversion unit 58 via the internal bus. The protocol conversion unit 58 converts the communication protocol of the data link layer of the received information request signal from the communication protocol of the terminal 1 to the communication protocol PPP of the public network, and via the internal bus, the public network connection unit 5
Send to 6. The public network connection unit 56 transmits the received information request signal to the server device 2 via the modem 4 and the public network.

On the other hand, when an information signal (ATM cell) is transmitted from the satellite line receiving device 8, the satellite line connection unit 60
Receives the information signal and sends it to the ATM via the internal bus.
The data is transmitted to the filtering unit 62. The ATM filtering unit 62 selects only the ATM cells addressed to the accommodation terminal from the received information signals (ATM cells), and outputs the selected information signals (ATM cells) via the internal bus to the protocol conversion unit 58. Send to The protocol conversion unit 58
After assembling the received information signal (ATM cell) into an IP packet, one end is transmitted to the IP filtering unit 63. The IP filtering unit 63 selects an IP packet addressed to the accommodation terminal based on the held IP address, and transmits the selected IP packet to the protocol conversion unit 63 again. The protocol conversion unit 63 converts the communication protocol of the data link layer of the received information signal from the ATM protocol of the satellite line to the communication protocol of the data link layer on the terminal 1 side. 52. The terminal connection unit 52 transmits the received information signal to the terminal 1 side.

In the case of this embodiment, since the IP filtering unit 63 performs filtering based on the held IP address, even if the IP packet and the ATM cell do not uniquely correspond to each other, the IP address other than the one addressed to the accommodation terminal is used. No packet is transmitted from the satellite line connection device to the terminal.

§3. Third Embodiment FIG. 3 is a block diagram showing a configuration example of a satellite channel connection device according to a third embodiment of the present invention. This figure is
This corresponds to claim 3. In this figure, the satellite line connection device includes a terminal connection unit 72, a satellite line connection unit 70, a public network connection unit 76, an ATM filtering unit 80, a protocol conversion unit 78, and an address management unit 83. The public network connection unit 76, the ATM filtering unit 80, and the protocol conversion unit 78 are connected by an internal bus.

Here, the terminal connection section 72 transmits and receives information to and from a plurality of terminals. The satellite line connection unit 70 receives information from the satellite line receiving device 8. Public network connection unit 7
6 transmits information to the public network via the modem 4. A
The TM filtering unit 80 extracts cells addressed to the accommodation terminal from the ATM cells received via the satellite line. The protocol converter 78 converts the communication protocol of the data link layer on the terminal 1 side into a public network PPP, and
It has a function of converting the ATM protocol of the satellite line into the communication protocol of the data link layer on the terminal 1 side. Further, the protocol conversion unit 78 has a function of controlling an output destination of a signal input from each of the connection units (the terminal connection unit 72, the satellite line connection unit 70, and the public network connection unit 76). The address management unit 83 holds an IP address and a data link layer destination address for a plurality of connected accommodation terminals. Then, the address management unit 83 transmits the IP
Based on the address, an IP packet addressed to the accommodation terminal is extracted, and the destination address of the IP packet is associated with the destination address of the accommodation terminal in the data link layer. Each of the above-described components can be realized by a CPU (Central Processing Unit) that executes software that describes the operations described below, or a communication-specific LSI.

In such a configuration, when an information request signal is transmitted from the terminal 1, the terminal connection section 72 receives the information request signal and transmits the information request signal to the protocol conversion section 78 via the internal bus. The protocol conversion unit 78 converts the communication protocol of the data link layer of the received information request signal from the communication protocol of the terminal 1 to the communication protocol PPP of the public network, and via the internal bus, the public network connection unit 7
Send to 6. The public network connection unit 76 transmits the received information request signal to the server device 2 via the modem 4 and the public network.

On the other hand, when the information signal (ATM cell) is transmitted from the satellite line receiving device 8, the satellite line connection unit 70
Receives the information signal and sends it to the ATM via the internal bus.
It is sent to the filtering unit 80. The ATM filtering unit 80 selects only the ATM cells addressed to the accommodation terminal from the received information signals (ATM cells), and outputs the selected information signals (ATM cells) via the internal bus to the protocol conversion unit 78. Send to The protocol conversion unit 78
After assembling the received information signal (ATM cell) into an IP packet, one end is transmitted to the address management unit 83.

The address management unit 83 stores the IP
An IP packet addressed to the accommodation terminal is selected based on the address, a destination address of the selected IP packet is associated with a destination address of the data link layer of the accommodation terminal, and the selected I packet is selected.
The P packet is transmitted again to the protocol conversion unit 78 together with the corresponding data link layer destination address. The protocol conversion section 78 converts the communication protocol of the data link layer of the received information signal into the communication protocol of the data link layer of the terminal 1 based on the destination address notified from the address management section 83, and sets the internal bus. Via,
It is transmitted to the terminal connection unit 72. The terminal connection unit 72 transmits the received information signal to the terminal 1 side.

In the case of this embodiment, even when a plurality of terminals are connected to the satellite line connection device, each terminal receives only packets addressed to its own terminal and does not receive packets addressed to other terminals. .

Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to the embodiments, and changes in design and the like may be made without departing from the gist of the present invention. The present invention is included in the present invention.

[0026]

As described above, according to the present invention, the terminal
Support one data link layer communication protocol,
By maintaining only one line, communication with the server device can be performed using the public network and the satellite line, without being aware of the communication path, and sending packets other than the own terminal to the terminal. Therefore, the effect of reducing the load on the terminal can be obtained. Further, since the destination address of the IP packet is associated with the destination address of the data link layer between the terminal and the satellite line connection device, a plurality of terminals can be connected to the satellite line connection device.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration example of a satellite channel connection device according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration example of a satellite channel connection device according to a second embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration example of a satellite channel connection device according to a third embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration example of a communication system using a satellite line connection device according to a conventional technique.

FIG. 5 is a block diagram showing a configuration example of a satellite line connection device according to a conventional technique.

[Explanation of symbols]

1 ... terminal, 4 ... modem, 8 ... receiving device, 3
2, 52, 72 ... terminal connection part, 36, 56, 76 ...
... Public network connection unit, 38, 58, 78 Protocol conversion unit, 40, 60, 70 Satellite line connection unit, 62, 80
... ATM filtering unit, 63 ... IP filtering unit, 83 ... Address management unit

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Hiroshi Nakajima 3-19-2 Nishishinjuku, Shinjuku-ku, Tokyo Nippon Telegraph and Telephone Corporation

Claims (3)

[Claims] 1. UDP (User Datagram Protocol) / IP (Internet Protocol), TCP
(Transmission Control Protocol) /
In computer communication performed using the IP technology, a server device storing information and a terminal requesting the information are connected via a public network and a satellite line, and an information request signal from the terminal to the server device is transmitted through the public network. The information signal from the server device to the terminal passes through a satellite line, and the satellite line and the public network use a communication protocol different from the communication protocol below the data link layer used by the terminal, and A satellite line connection device used in a communication system in which a communication protocol of a data link layer of a public network is different, a satellite receiver for receiving a signal of a satellite line, a modem connected to a public network, and connected to the terminal, Terminal connection means for transmitting / receiving signals to / from the terminal; satellite line connection means for receiving signals from a satellite receiver; A satellite network connection device comprising: a public network connection means for performing communication; and a protocol conversion means for mutually converting each communication protocol. 2. The communication system according to claim 1, wherein
As a communication protocol of a data link layer for transmitting and receiving IP packets, a public network section uses PPP (point-to-point protocol), and a satellite line section uses ATM.
A satellite line connection device used when performing communication using a protocol, a terminal connection means for transmitting / receiving a signal to / from the terminal, a satellite line connection means for receiving a signal from a satellite reception device, and a modem Public network connection means for transmitting and receiving signals, ATM filtering means for extracting cells addressed to the terminal from ATM cells received via a satellite line, protocol conversion means for terminating PPP and ATM protocols, and IP address for the terminal An IP filtering unit for extracting a packet, wherein the protocol conversion unit converts a communication protocol of a data link layer on the terminal side into a public network PPP.
A satellite that has a function of converting an ATM protocol of a satellite line into a data link layer protocol on the terminal side, and further has a function of controlling an output destination of a signal input from each of the connection units. Line connection equipment. 3. The communication system according to claim 1, wherein
A satellite line connection device used when performing communication using the communication protocol of the data link layer according to claim 2, wherein the device is connected to a plurality of terminals by a bus-type connection, and transmits and receives signals to and from the plurality of terminals. Connection means for receiving signals from a satellite receiver, a public network connection means for transmitting and receiving signals to and from a modem, and a cell destined for the own terminal from an ATM cell received via a satellite line. ATM filtering means for extracting, protocol converting means for terminating PPP and ATM protocols, managing destination addresses of the plurality of terminals in the data link layer, extracting only IP packets addressed to the plurality of terminals,
A satellite line connection apparatus comprising: address management means for associating a destination address of a P packet with a destination address of a data link layer.