JP3431509B2 - Secret communication system and secret device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
Confidential communication using a full-duplex communication line, in which data is transmitted from the sender to the receiver in only one direction (hereinafter referred to as "downlink") and which uses a long-cycle synchronization code. One-to-one between sender and receiver in the system
In contrast to the confidential communication system in which communication is a principle, a confidential communication system that can realize the confidential device on the transmitting side by one unit can be configured, and even if the synchronization is lost due to slip or the like in the transmission section, only terminals that are out of synchronization The present invention relates to a confidential communication system and a confidential communication device having a control line (hereinafter referred to as “uplink”) from the reception side to the transmission side for the confidential communication device so that the resynchronization operation can be performed.

[0002]

BACKGROUND OF THE INVENTION Conventionally, in a multi-location one-system communication system,
There is a secret communication system shown in FIGS. 5 to 7 that employs the full-duplex communication system. The transmission side in the conventional confidential communication system shown in FIG. 5 includes a telephone 2 which is a digital telephone that outputs actual information, a multipoint control device B18 that performs call control and the like on a preset line, The multi-point control device B18 is composed of a general station B17 including a confidential communication device C19 which is provided for each line selected by the multipoint control device B18 and performs a confidential processing.

Further, the receiving side has a terminal station n20 (however, n
Is from 1 to N, and N is different depending on the system), and this terminal station n20 has a confidential device D21 for restoring the concealed information and a telephone 2 for receiving the actual information.
It is composed of and. Then, each of these terminal stations n20
And the central office B17 are connected to each other via a wired exchange network, and the confidential communication information signal oscillated via the confidential communication device C19 of the central office B17 is transmitted to the respective terminal stations via the wired exchange network. It is input to n20.

By the way, the confidential communication device C19 in the conventional confidential communication system includes an arithmetic circuit A as shown in FIG.
7, resynchronization request signal detection circuit 8, resynchronization signal generation circuit 1
1 and an initial information storage circuit 10. Here, when the information is input from the telephone 2, the arithmetic circuit A7 performs the confidential processing on the information and outputs the information on the confidential processing to the initial information storage circuit 10, and resynchronization is performed. The request signal detection circuit 8 detects the presence / absence of a resynchronization request signal from the terminal station n20 which is out of synchronization, discards the received data when there is no resynchronization request signal, and when there is,
This is a circuit that outputs a request signal to the resynchronization signal generation circuit 11.

The initial information storage circuit 10 includes an arithmetic circuit A
7 is a circuit capable of receiving the initial information that has been subjected to the confidentiality processing from 7, and storing the initial information, and outputting the initial information in response to a request from the resynchronization signal generation circuit 11. When the request signal is input from the resynchronization request signal detection circuit 8, the resynchronization signal generation circuit 11 receives the initial information from the initial information storage circuit 10 and is out of synchronization via a predetermined line.
The resynchronization signal is output to.

As shown in FIG. 7, the confidential device D21 has a circuit configuration including a synchronization acquisition circuit 13, a synchronization monitoring circuit 14 and an arithmetic circuit B16. Synchronization acquisition circuit 1
Reference numeral 3 captures synchronization from the input signal, and if synchronization can be captured, an information signal for which synchronization can be captured is output to the synchronization monitoring circuit 1
4 and outputs the information signal for which synchronization cannot be captured to the synchronization monitoring circuit 14.

Alternatively, when there is a resynchronization information signal, the circuit recaptures the synchronization from the input signal and outputs the synchronized information to the synchronization monitoring circuit 14 as in the previous term. When the synchronization monitoring circuit 14 receives the information signal of which the synchronization is captured from the synchronization capturing circuit 13, the synchronization monitoring circuit 14 outputs the arithmetic circuit B16.
Is a circuit for outputting a re-synchronization request signal to the re-synchronization signal generation circuit 11 on the transmitting side when the reception information signal is output to the re-synchronization signal generation circuit 11 and the information signal whose synchronization cannot be captured is input from the synchronization acquisition circuit 13. .

The arithmetic circuit B16 restores the information concealed by the received information signal input from the synchronization acquisition circuit 14 to the original information, and outputs the information signal sent from the control station B17 to the telephone set 2. Circuit.

[0009]

The confidential communication system of the conventional type described above also uses a full-duplex communication line in a multi-site system as in the present invention, and data transmission is performed from the transmission side to the reception side. Is a one-way communication (hereinafter, referred to as “downlink”) and uses a long-period synchronous code, that is, one-to-one communication is basically performed between the transmitting side and the receiving side. The conventional confidential communication device requires the number of registered confidential communication devices on the transmission side, and as the number of registration increases, the device itself increases in size.

Moreover, when the receiving side terminal station is out of synchronization due to various conditions such as the transmission path, the terminal station itself cannot pull in the synchronization because the synchronization code has a long cycle. In order to resynchronize a terminal station that is out of synchronization, a resynchronization signal must be sent from the transmitting side to all terminal stations on the receiving side. The secret device
Since it is not possible to determine whether or not the synchronization could not be pulled in, in order to search for this, the entire communication system including other terminal stations that are out of synchronization must be moved to the resynchronization mode, and the entire system is temporarily I had problems such as stopping at.

The present invention is to solve the above-mentioned problems, and in a confidential communication system in which the confidential device of the central station is one, the confidential devices of a plurality of terminal stations connected to the central station are installed.
Of the terminal, one terminal station's secret talk device and the control station's secret talk device
If the confidential processing between and is out of sync, this out of sync
Only the secret device of one terminal station can be resynchronized.
An object of the present invention is to provide a confidential communication system and an confidential device capable of achieving the following.

[0012]

[Means for Solving the Problems] First, a general station and a terminal station.
And were connected by a full-duplex communication line, and confidential processing was performed.
Data is transmitted only in one direction from the controlling station to the terminal station.
In the confidential communication system, the system is
The confidential device installed and the device installed in the terminal station
That and a scrambler, the scrambler of the control station includes a storage times
And the information to be transmitted to the terminal station,
The initial information on the confidential processing of is stored in the memory circuit.
And the signal sent from the terminal station
Device number and the memory number
Resynchronization required to request retransmission of initial information stored in the path
The resynchronization request signal including
Re-sync request that outputs this re-sync request signal when detected
And a resynchronization request signal from the resynchronization request detection circuit.
Signal is input, it is included in the input resynchronization request signal.
The device number that is rare and the terminal that is connected to its own station
Check whether the device number that identifies the secret device of the station matches.
Device identification times that identify and output the device number if they match
And the device number is input from the device identification circuit,
This device number and initial information stored in the storage circuit
Resync signal generation that generates and sends a resync signal that includes and
And a formed circuit, the scrambler of the terminal station, the control station
The resynchronization signal transmitted is received, and the received resynchronization signal is received.
The device number included in the period signal and the confidential communication device of the own terminal station
Identify whether the device number that identifies
Device identification circuit that outputs the received resynchronization signal
And included in the resynchronization signal from the device identification circuit.
Based on the initial information, the secret communication device of the general station and the secret of the own terminal station
Capture confidentiality synchronization that synchronizes confidentiality processing with the device
Output the initial information contained in the received resynchronization signal
Secure synchronization circuit and the synchronization acquisition circuit
A synchronization monitoring circuit that monitors whether or not捉, the synchronization superintendent
If the visual circuit determines that confidential synchronization cannot be captured,
The device number that identifies the secret device of the terminal station and the secret
Resend the initial information stored in the memory circuit of the speaker
A resync request signal that includes a resync request
And a resynchronization request signal generation circuit for transmitting the signal.

[0013] Second, the scrambler of the terminal station, the same
If it is determined that the secret synchronization has been acquired by the period monitoring circuit,
Based on the initial information from the synchronization acquisition circuit,
Restoration process of confidential information sent from the station
It has an arithmetic circuit for performing processing.

Thirdly, the arithmetic circuit of the secret communication device of the terminal station
Determined that, concealment synchronization can not be caught by the synchronization monitoring circuit
If it is done, the confidential processing
It is configured to stop the restoration process of applied information.
It

Fourthly, it is transmitted from the secret communication device of the general bureau.
The resynchronization signal that is
It will be sent to the terminal station in the format. Fifth, the down
The frame format on the ring line is
In addition to the issue, the secret processing is performed by the arithmetic circuit of the secret communication device of the general bureau.
Contains information that has been applied.

Sixth, device identification of the confidential communication device of the terminal station
The circuit is included in the resync signal sent from the
Device number and the device that identifies the confidential device of the own terminal station
If the numbers do not match, the received resync signal is deleted.
Is configured to.

Seventh, it is transmitted from the confidential communication device of the terminal station.
The resynchronization request signal is a frame on the uplink line.
It is sent to the Bureau in a format.

Eighth, full-duplex communication is performed between the control station and the terminal station.
Connected with a line, the transmission of data that has been encrypted is controlled.
One-way secret communication system from the central station to the terminal station
It is a secret talking device installed in the general bureau of
Synchronization of confidential processing between the confidential device and the confidential device of the own terminal station
A memory circuit initial information is stored for taking the
From the signal transmitted from the terminal station, the confidential device of the terminal station
The device number for identifying the
Resynchronization request including resynchronization request for requesting retransmission of period information
This resynchronization occurs when a signal is detected and a resynchronization request signal is detected.
A resynchronization request detection circuit for outputting a period request signal, the resync
When the resynchronization request signal is input from the synchronization request detection circuit, this
Device number included in the resynchronization request signal input by the
And identify the confidential device of the terminal station connected to its own station
Identify whether the device number to be
If the device identifying circuit which outputs the device ID, the device identification
When the device number is input from the circuit, this device number and the
Resynchronization signal including initial information stored in the memory circuit
And a resynchronization signal generation circuit for generating and transmitting the signal.

Ninth, the full-duplex communication cycle between the control station and the terminal station.
Connected with a line, the transmission of data that has been encrypted is controlled.
One-way secret communication system from the central station to the terminal station
A is installed in the terminal station scrambler, the overall
The resynchronization signal transmitted from the station is received, and this reception
Device number included in the resynchronization signal and the secret story of the own terminal station
Identify whether the device number that identifies the device matches
Device identification circuit and included in the resynchronization signal in the device identification circuit
A device that identifies the device number and the confidential device of the local terminal station
If it is identified that the numbers match, the device identification circuit
Based on the initial information contained in the resync signal received by
The secret communication device between the secret communication device of the own terminal station and the secret communication device of the control station.
And a synchronization capturing circuit for capturing the synchronization of logic
Conceal processing between the confidential device of the own terminal station and the confidential device of the general station
A synchronization monitoring circuit that monitors whether or not the synchronization of
The synchronization monitoring circuit uses the secret talk device of the own terminal station and the secret talk of the general station.
If it is determined that the synchronization of the confidential processing with the device has been acquired,
In this case, the device number that identifies the confidential device of the own terminal station and the
The initial information stored in the memory circuit of the station will be retransmitted.
A resynchronization request signal including the resynchronization request
The resynchronization request signal generation circuit that transmits to the control station.
Have.

[0020]

[0021]

[0022]

[0023]

1 is a block diagram of an embodiment of the present invention. In the figure, the same components as those in FIGS. 2, 3 and 5 are designated by the same reference numerals. The embodiment shown in FIG. 1 is an example in which the transmission-side confidential communication device A3 is one. In FIG.
The transmitting side is indicated by the control station A1, and the control station A1 performs call control and the like on the telephone 2, which is a digital telephone that outputs actual information, the confidential communication device A3 that performs the concealment process, and a preset line. It is configured by a multipoint control device A4.

The receiving side is connected to the terminal station n5 (where n is 1
Up to N, where N is different depending on the system), and all terminal stations n5 have the same configuration. The terminal station n5 is composed of a confidential communication device B6 that restores concealed information and a telephone 2 that receives actual information. The control station A1 and the terminal station n5 are connected to each other by wire via an exchange network.

In the general office A1, the telephone 2 inputs the information signal to be transmitted to the confidential device A3. As shown in FIG. 2, the confidential device A3 has a circuit configuration including an arithmetic circuit A7, a resynchronization request signal detection circuit 8, a device identification circuit A9, a resynchronization signal generation circuit 11, and an initial information storage circuit 10.

In the figure, the same components in FIG. 3 and FIGS. 6 and 7 are designated by the same reference numerals. Here, when the information is input from the telephone 2, the arithmetic circuit A7 is a circuit that performs the confidential processing on the information and outputs the information on the confidential processing to the initial information storage circuit 10.

The resynchronization request signal detection circuit 8 detects the presence / absence of a resynchronization request signal from the terminal station n5 which is out of synchronization, discards the received data when there is no synchronization signal, and when there is any, notifies the device identification circuit A9. Is a circuit for outputting a resynchronization request signal.
By the way, the device identification circuit A9 has the device number of the confidential device B6 used in the system registered therein, and is registered in advance from the resynchronization request signal sent from the terminal station n5 out of synchronization. It is a circuit for identifying whether the device number is a given device number, and if there is a corresponding device number, adds the device number, and if not, adds a special signal and outputs it to the resynchronization signal generation circuit 11.

The initial information storage circuit 10 is a circuit capable of receiving the confidential information subjected to the confidential processing from the arithmetic circuit A7, storing the initial information, and outputting the initial information in response to a request from the resynchronization signal generating circuit 11. Resynchronization signal generation circuit 1
1 receives the initial information from the initial information storage circuit 10 due to the input of the signal from the device identification circuit A9, adds the device number input from the device identification circuit A9 to the initial information, and resynchronizes the line. Is a circuit for outputting.

The transmission signal output from the confidential device A3 is
Through the multipoint control unit A4, the data is transmitted in a frame format as shown in FIG. 4 (a: frame format on the down ring line) to the terminal station n5 connected like a broadcast format. Where FDm and DATAm
(However, m is 1 to M, and M differs depending on the data amount of the transmission signal.) Each data amount differs depending on the system.

Further, the FDm includes a control signal (not used in the confidential device A3 and the confidential device B6) between the transmitting side telephone 2 and the receiving side telephone 2, a normal transmission synchronizing information signal and a resynchronizing information signal. And the DATAm is
It is composed of an information signal that has been subjected to a concealment process. Further, as shown in FIG. 3, the confidential device B6 has a circuit configuration including a device identification circuit B12, a synchronization acquisition circuit 13, a synchronization monitoring circuit 14, a resynchronization request signal generation circuit 15, and an arithmetic circuit B16.

In the figure, the same components as those in FIGS. 6 and 7 are designated by the same reference numerals. Here, the device identification signal B12
When FD1 is sent and when there is no resynchronization information signal in FDm after FD2, FD2 after FD2
When there is a resynchronization information signal in m and the device number included in the resynchronization information signal matches the own device number, the reception signal is output to the synchronization acquisition circuit 13 as it is. If there is a resynchronization information signal in FDm after FD2, and if the device number included in the resynchronization information signal and the own device number do not match, the resynchronization information signal is deleted and other signals are deleted. Is output to the synchronization acquisition circuit 13 as a reception signal.

Further, when there is a resynchronization information signal in the FDm after FD2 and a special number is included, when the resynchronization request signal is output by itself, it is directly sent to the synchronization acquisition circuit 13. It is a circuit that outputs a reception signal to the synchronization acquisition circuit 13 and outputs other signals as a reception signal to the synchronization acquisition circuit 13 when the reception signal is output and the resynchronization request signal is not output.

The synchronization acquisition circuit 13 is a device identification circuit B12.
If there is no re-synchronization information signal in the signal input more, the synchronization is captured from the input signal, and if the synchronization can be captured, the information signal whose synchronization has been captured is output to the synchronization monitoring circuit 14, In addition, the synchronization information signal and the concealed information signal (hereinafter referred to as "reception information signal") are output to the arithmetic circuit B16, and if the synchronization cannot be captured, the synchronization monitoring circuit 14 outputs the information signal for which the synchronization cannot be captured. Output to.
Alternatively, if there is a re-synchronization information signal, the input signal is re-synchronized, and the synchronized information is output to the synchronization monitoring circuit 14 as in the previous term, and the arithmetic circuit B16
It is a circuit that outputs a reception information signal to.

When the synchronization monitor circuit 14 receives the information signal from which the synchronization cannot be captured from the synchronization capture circuit 13, it outputs a signal for outputting the device number to the device identification circuit B12, and the device identification circuit B12 outputs the signal. After the device number is input, the device number and a signal related to the resynchronization request are output to the resynchronization signal generation circuit 15, while a signal for instructing the arithmetic circuit B16 to stop the processing is output.

The re-synchronization request signal generation circuit 15 generates a re-synchronization request signal by adding its own device number which is simultaneously input when a signal related to re-synchronization is input from the synchronization monitoring circuit 14. It is a circuit for outputting a resynchronization request signal FUm (where m is the same as m of FDm) in a frame format as shown in FIG. 4 (b: frame format on the uplink line) to the station A1. .

The arithmetic circuit B16 restores the information concealed by the received information signal input from the synchronization acquisition circuit 13 to the original information, and outputs the information signal sent from the general station A1 to the telephone set 2. When a stop signal is input from the synchronization monitoring circuit 14, the restoration processing is stopped. Next, the operation of this embodiment shown in FIGS. 1 to 3 will be described.

Now, in the system shown in FIG. 1, it is assumed that the number of terminal stations n5 used is N. First, the multipoint control unit A4 sets up a line from the control station A1 to the terminal station n5. After the line is established, communication is started from the telephone 2 of the general office A1, and an information signal is output to the confidential device A3. This information signal is input to the inside of the confidential device A3, and the arithmetic device A7 opposes the FD1 to the confidential device B.
6 adds initial information capable of obtaining confidential synchronization and a control signal used in the telephone 2 (here, resynchronization information is not added),
In addition, after FD2, information that allows the subsequent communication synchronization is added, and the information signal input from the telephone 2 is subjected to a concealment process, and the transmission signal is output to the multipoint control unit A4 by adding it to the frame format.

The arithmetic circuit A7 also outputs the initial information added by the FD1 to the initial information storage circuit 10. The initial information storage circuit 10 stores the initial information.
The transmission signal input to the multipoint control unit A4 distributes the data to N pieces of lines set in advance, and outputs the same signal as the transmission signal input to all the lines. The transmission signal output from the multipoint control unit A4 passes through the transmission line,
It is input to each terminal station n5. The terminal station n5 is the control station A1
The transmission signal from the device is received as a reception signal, and the confidential device B6
The received signal is input to.

This received signal is input to the inside of the confidential device B6 and detected by the device identification circuit B12 by FD1.
The FD1 is input to the synchronization acquisition circuit 13 as it is, and the FD1
Of the initial information signal and the received information signal, the synchronization is captured from the initial information signal, and when the synchronization can be captured, the information signal and the received information signal for which the synchronization can be captured are calculated by the arithmetic circuit B1.
6 and the information signal indicating that the synchronization can be captured to the synchronization monitoring circuit 14.

The arithmetic circuit B16 restores the information concealed by the input received information signal to the original information and outputs the information signal sent from the general bureau A1 to the telephone 2 to enable communication. Become. If the synchronization acquisition circuit 13 cannot acquire the synchronization, the synchronization monitoring circuit 14 outputs an information signal for which the synchronization cannot be acquired. The synchronization monitoring circuit 14 to which the information signal whose synchronization cannot be captured is input requests the device number from the device identification circuit B12 and receives its own device number.

After that, the synchronization monitoring circuit 14 outputs a signal relating to the resynchronization request and its own device number to the resynchronization request signal generation circuit 15, and the resynchronization request signal generation circuit 15 which has received these signals, Frame format F
A resynchronization request signal is output to the control station A1 on Um. The resynchronization request signal input to the confidential device A3 via the multipoint control device A4 of the general station A1 is input to the internal resynchronization request signal detection circuit 8 of the confidential device A3.

The resynchronization request signal detection circuit 8 detects the resynchronization request signal from the FUm, discards the signal if it is not detected, and identifies the device number from the signal if detected. . Resynchronization Then, if the identified device number is the device number registered in the device identification circuit A9, the device number is output to the resynchronization signal generation circuit 11, and if not, the special number is output to the resynchronization signal generation circuit 11.

When the signal is input from the device identification circuit A9, the resynchronization signal generation circuit 11 adds the input device number or special number and receives the initial information from the initial information storage circuit 10, and then FDm Insert a resync signal into
Output to the multipoint control unit A4. After that, it is transmitted to the terminal station n5 via the line. According to the operation of the terminal station n5 from the received signal received by the terminal station n5, the terminal station n5 that outputs the resynchronization request signal performs the resynchronization operation, and the terminal station n5 that does not output the resynchronization request signal resynchronizes. Do not do.

As a result, according to this embodiment, a full-duplex communication line is used in a multi-site system, data is transmitted only in one direction from the transmission side to the reception side, and the transmission side is kept secret. Even when the number of devices is one and the synchronization is lost on the receiving side, the resynchronization operation can be performed only on the terminal which is out of synchronization. Note that the present invention is not limited to the above-described embodiment, and can be applied by adding an A / D conversion circuit to the confidential device when the phone is an analog phone, for example.

When the transmission section is a wireless system, it can be applied by deleting the multipoint control circuit and adding an omnidirectional transceiver to the transmitting side and the receiving side.

[0046]

As described above, according to the present invention,
By adding the device identification circuit, it is possible to prevent re-synchronization operation from being performed on the receiving side device whose synchronization has been captured, and to prevent the entire system from temporarily shifting to re-synchronization operation. Is improved.

In addition, since only one confidential communication device can be used on the transmission side, there is a great effect in terms of cost in system configuration.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a confidential communication system and an confidential communication device according to the present invention.

FIG. 2 is a block diagram showing an embodiment of a confidential communication device in the confidential communication device on the side of the general station shown in FIG.

FIG. 3 is a block diagram showing an embodiment of a confidential communication device on the terminal station side shown in FIG.

4 (a) and 4 (b) are explanatory diagrams showing frame formats on a down-ring and an up-ring line used in a confidential communication system and a confidential communication device according to the present invention.

FIG. 5 is a block diagram showing an embodiment of a conventional confidential communication system and confidential communication device.

6 is a block diagram showing an embodiment of a confidential communication device in the confidential communication device on the control station side shown in FIG.

7 is a block diagram showing an embodiment of a confidential communication device on the terminal station side shown in FIG.

[Explanation of symbols]

A1 Administration Bureau 2 Digital telephone A3 confidential device A4 multipoint control device n5 terminal station B6 Secret device A7 arithmetic circuit 8 Resynchronization request signal detection circuit A9 Device identification circuit 10 Initial information storage circuit 11 Resynchronization signal generation circuit B12 Device identification signal 13 Synchronization acquisition circuit 14 Synchronous monitoring circuit 15 Resynchronization signal generation circuit B16 arithmetic circuit

Claims (9)

(57) [Claims] 1.The control station and terminal station are connected by a full-duplex communication line.
Is the control station transmitting the data that has been
In a confidential communication system that is only one-way from the terminal to the terminal station
hand, The system is a secret talking device installed in the control station,
And a secret communication device installed in the terminal station, The secret talking device of the general bureau is A memory circuit, The information transmitted to the terminal station is subjected to confidentiality processing,
Calculation for storing initial information regarding processing in the storage circuit
Circuit, From the signal transmitted from the terminal station, the secret story of the terminal station
The device number that identifies the device and the value stored in the memory circuit
Resynchronization including a resynchronization request requesting retransmission of initial information
When a request signal is detected and a resynchronization request signal is detected, this
A resynchronization request detection circuit that outputs a resynchronization request signal, A resynchronization request signal is input from the resynchronization request detection circuit.
The device included in this input resynchronization request signal.
Location number and confidential device of the terminal station connected to its own station
Identify whether the device number that identifies
Device identification circuit that outputs the device number, When the device number is input from the device identification circuit, this device is
Including the serial number and the initial information stored in the storage circuit.
Circuit for generating and transmitting a resynchronization signal
Has and The confidential device of the terminal station, Receives the re-synchronization signal sent from the
The device number included in the received resynchronization signal and the own terminal station
Whether or not the device number that identifies the confidential device of
If they match, the device that outputs the received resynchronization signal
A device identification circuit, Initial contained in the resynchronization signal from the device identification circuit
Based on the information, the secret communication device of the control station and the secret communication device of the own terminal station
Confidentiality synchronization that synchronizes confidentiality processing with Capture and receive
Outputs the initial information contained in the received resynchronization signal.
A period acquisition circuit, Monitors whether or not secret synchronization can be captured by the synchronization acquisition circuit
A synchronous monitoring circuit that The synchronization monitoring circuit determines that confidential synchronization cannot be captured.
If the device number that identifies the confidential device of the own terminal station and the
Initial information stored in the memory circuit of the secret communication device of the general bureau
Resynchronization request, including resynchronization request to retransmit
Resynchronization request signal generation circuit that generates and transmits signals
A confidential communication system characterized by: 2.The confidential device of the terminal station, It was judged that the secret synchronization could be captured by the synchronization monitoring circuit.
, Based on the initial information from the acquisition circuit,
Of the confidential information sent from the
Contractor characterized by having an arithmetic circuit for performing restoration processing
The confidential communication system according to claim 1. 3.The arithmetic circuit of the confidential device of the terminal station, The synchronization monitoring circuit determines that confidential synchronization cannot be captured.
In the case of
Configured to stop the restoration of the stored information.
The confidential communication system according to claim 2, wherein: 4. The re-transmission transmitted from the secret communication device of the control station.
The sync signal is the frame format on the down ring line.
The information is transmitted to the terminal station by the Internet.
The confidential communication system described. 5. A frame fork on the down ring line.
The mat is a secret story of the control station in addition to the resynchronization signal.
Contains information that has been subjected to confidential processing by the arithmetic circuit of the device.
The confidential communication system according to claim 4, characterized in that
Mu. 6.Device identification circuit of the secret device of the terminal station
Is The device included in the resynchronization signal transmitted from the control station.
The device number and the device number that identifies the confidential device of the own terminal station
If there is no match, remove the received resync signal
The secret story according to claim 1, wherein the secret story is configured.
Communications system. 7. The re-transmission transmitted from the confidential device of the terminal station.
Synchronization request signal, frame Four on A Ppuringu line
The information is transmitted to the general bureau by Matt.
The confidential communication system according to 1. 8.The control station and terminal station are connected by a full-duplex communication line.
Is the control station transmitting the data that has been
Summary of the confidential communication system that is only one-way from the terminal to the terminal station
It is a secret device installed in the station, Concealment between the secret station of the general station and the secret station of the own terminal station
A memory circuit that stores initial information for synchronizing
When, From the signal transmitted from the terminal station, the secret story of the terminal station
The device number that identifies the device and the value stored in the memory circuit
Resynchronization including a resynchronization request requesting retransmission of initial information
When a request signal is detected and a resynchronization request signal is detected, this
A resynchronization request detection circuit that outputs a resynchronization request signal, A resynchronization request signal is input from the resynchronization request detection circuit.
The device included in this input resynchronization request signal.
Location number and confidential device of the terminal station connected to its own station
Identify whether the device number that identifies
Device identification circuit that outputs the device number, When the device number is input from the device identification circuit, this device is
Including the serial number and the initial information stored in the storage circuit.
Circuit for generating and transmitting a resynchronization signal
The secret talking device of the general bureau characterized by having. 9.The control station and terminal station are connected by a full-duplex communication line.
Is the control station transmitting the data that has been
From a terminal to a terminal station in a confidential communication system that is only unidirectional
It is a secret device installed in the station, When receiving the re-synchronization signal transmitted from the control station,
Device number and own terminal included in the resynchronization signal received by
Check whether the device number that identifies the secret device of the station matches.
A device identification circuit for identifying, Device number included in the resynchronization signal in the device identification circuit
And the device number that identifies the confidential device of the own terminal station match
Resynchronization received by the device identification circuit
Based on the initial information included in the signal, the secret of the own terminal station
Synchronize the confidential processing between the talking device and the secret station of the control station.
Synchronization acquisition circuit, The synchronization acquisition circuit uses the secret talk device of the own terminal station and the secret talk of the general station.
Monitor whether or not the synchronization of the confidential processing with the device has been acquired
A synchronization monitoring circuit, The synchronization monitoring circuit uses the secret talk device of the own terminal station and the secret talk of the general station.
If it is determined that the synchronization of the confidential processing with the device has been acquired,
In this case, the device number that identifies the confidential device of the own terminal station and the
The initial information stored in the memory circuit of the station will be retransmitted.
A resynchronization request signal including the resynchronization request
The resynchronization request signal generation circuit that transmits to the control station.
A secret-talking device for a terminal station, characterized by having.