JP2000330943A - Security system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the system which is inexpensive, easily introduced, and improved in security by generating password key data corresponding to respective terminals and broadcasting a password update request to the respective terminals. SOLUTION: A password control part 48 is made to generate new password key data for each of optical subscriber line terminating devices (ONT). Then a message transmission and reception part 46 is made to generate password request update request messages. The password update request messages are generated for each of all ONTs 201 to 20N and sent out of an optical subscriber line accommodation device (OLT)-PON control part 45. The ONTs 201 to 20N having received them update passwords. Each ONT having received a password transmission request message sends a password to an OLT 21 with a reply message. Each terminal constitutes a password newly on the basis of its terminal number and each piece of password key data to improve the security.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a security system, for example, a security system for improving security in a passive optical network system.

[0002]

2. Description of the Related Art With the recent advances in optical communication technology and information processing technology, provision of multimedia information services such as video on demand (VOD) via a subscriber access network has been put to practical use. Has been reached. As one of communication forms suitable for providing such a multimedia information service, an international telecommunications union telecommunications standardization section (Internationa
l Telecommunication Union-Telecommunication: IT
UT) Recommendation G. 983 “High Speed opticalaccess
systems based on Passive Optical Network (PON) tec
hniques ”(February 1998)-Asynchronous Transform Mode
fer Mode-Passive Optical Network: ATM-PON)
There is a system.

FIG. 7 shows an outline of the configuration of such an ATM-PON system. The ATM-PON system includes an ATM switch 11 connected to an ATM network 10.
When provided with a local switch 12 and a terminal 13 ₁ to 13 _N for each subscriber access network. Are connected by optical fibers to the subscriber exchange 12 and the respective terminals 13 ₁ to 13 _N,
One-to-many connection is made by the star coupler 14. Thus, the communication information from the ATM network 10 is distributed via a star coupler 14 to the terminals 13 ₁ to 13 _N. A
The TM-PON system is thus a Star Coupler 1
4 makes it possible to take an economical communication form.

[0004] Since communication information addressed to each terminal from the ATM network 10 is broadcast to all terminals, security measures are required. The above ITU-T Recommendation G. In 983, it assigns a unique serial number for each terminal 13 ₁ to 13 _N, which can be a password is defined. That is, when the system is started, the password is collated for each terminal, and authentication and start of each terminal are confirmed. Thereafter, the local exchange 12 multiplexes ATM cells as communication information transferred for each destination from the ATM network 10,
Send to all authenticated terminals. At this time, information about each multiplexed and arranged ATM cell is added and transmitted. Each terminal that has received the communication information to which such arrangement information has been added from the local exchange 12 refers to the arrangement information and extracts only the ATM cells addressed to the own terminal.

Techniques for improving security include:
There is a security system to which an encryption technology using an encryption key is applied, which can dramatically improve security. For example, Japanese Unexamined Patent Publication No. Hei 5-347617, "Communication method of wireless communication system", includes a terminal to which confidential information unique to a time apparatus and public information of an exchange are issued, and an exchange to which confidential information of its own apparatus is issued. . The terminal generates authentication information in which the secret information of the own device is applied to the key distribution information obtained by encrypting the random number generated by the own terminal with the public information of the exchange and the random number generated by the exchange. The exchange, to which the key distribution information and the authentication information generated in this way are notified, determines whether or not the random number, the key distribution information, and the authentication information generated by the switching device satisfy a predetermined relationship. Authenticate. A technology related to a security system has been disclosed in which an exchange encryption key is obtained from key distribution information at the time of authentication and secret information of the exchange, and an encryption key of a terminal is obtained from a random number generated by the exchange and public information of a base station. ing.

[0006]

The above-mentioned ATM-PO
In the ITU-T Recommendation G.N. The password based on the serial number of each terminal specified in 983 is retained as it is once the subscriber exchange obtains the password, and is not changed thereafter, thus lowering the reliability in terms of security. I will. In particular, ATM-P
In the ON system, since terminals are installed at each subscriber's house, information such as a serial number and a password is read maliciously from a built-in memory of the terminal, and password data is easily analyzed. There's a problem. In addition, each terminal is frequently turned on and off, and its installation location is moved, so that there is a problem that a decrease in confidentiality cannot be avoided. Furthermore, ITU-T
Recommendation G. 983 specifies that communication information is transmitted and received by encryption using a predetermined channel. However, due to such low confidentiality, communication is subsequently performed with a terminal that is incorrectly authenticated at the time of startup, and even if communication is performed by encryption, the confidentiality may be significantly reduced. . It is conceivable to apply the encryption technique disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 5-347617 for such a decrease in security. However, with the introduction of encryption technology, the processing becomes complicated and the cost of the device increases, and the ITU-T Recommendation G. Since it is necessary to significantly change the specifications specified in 983, a large-scale ATM-PO
There is a problem that application to the N system is impossible.

It is an object of the present invention to provide a security system which can be easily introduced into a conventional system at low cost and improves security.

[0008]

According to the first aspect of the present invention, (a) password key data generating means for generating password key data for each connected terminal, and a password generated by the password key data generating means. A terminal accommodating device having a broadcasting means for simultaneously broadcasting a password update request including key data to the terminal; and (b) transmitting the password key data of the terminal itself from the password update request broadcast by the broadcasting means. A plurality of terminals including a password key data extracting unit to be extracted, and a password updating unit for updating a password based on a terminal number uniquely assigned in advance and the password key data extracted by the password key data extracting unit. Provide security system.

According to the first aspect of the present invention, in a communication system in which a terminal accommodating device and a plurality of terminals are connected in a one-to-many connection, a password key data generating means of the terminal accommodating device has a password corresponding to each terminal. Key data is generated, and the broadcast means simultaneously broadcasts a password update request including the password key data to each terminal. In each terminal receiving this, the password key data extracting means extracts the password key data of the embodiment terminal included in the broadcasted password update request, and the password updating means extracts the terminal number predetermined for the terminal. The password which newly composes the password is updated based on the extracted password key data.

[0010] According to the second aspect of the present invention, (a) password key data generating means for generating password key data for each terminal to be connected, and a password containing password key data generated by the password key data generating means. Broadcasting means for simultaneously broadcasting an update request to terminals, password transmission requesting means for requesting transmission of a password for each terminal, password key data generated by password key data generating means and a terminal pre-assigned to the terminal. Password generating means for generating a password based on the number, and password matching means for matching, for each terminal, a password received from each terminal corresponding to the password transmission requesting means and a password generated by the password generating means for each terminal. And (b) this Password key data extraction means for extracting the password key data of the own terminal from the password update request broadcast by the notification means, a terminal number uniquely assigned in advance and the password key data extracted by the password key data extraction means The security system includes a plurality of terminals including a password updating unit that generates a password based on the password and a password returning unit that returns the password of the terminal itself when the password transmission request unit requests the transmission of the password.

That is, according to the second aspect of the present invention, in addition to the first aspect of the present invention, the password transmission requesting means is made to request the transmission of the password for each terminal. Each terminal that receives the password returns the password of the terminal itself updated by the password updating unit by the password returning unit. On the other hand, in the terminal accommodating apparatus, the password is generated by the password generating means based on the password key data and the terminal number uniquely assigned to the terminal, and the password of the terminal returned as described above is collated. ing.

According to the third aspect of the present invention, in the security system according to the second aspect, when the terminal accommodating device determines that the password received by the collating means and the password generated by the password generating means are inconsistent, It is characterized by comprising transmission stop means for stopping transmission to a terminal whose password is inconsistent.

That is, according to the third aspect of the present invention, in addition to the second aspect of the invention, when the password matching means of the terminal accommodating device determines that the passwords are inconsistent, the password is not matched. Only the transmission to the terminal determined to have been stopped is immediately stopped by the transmission stop means. As a result, confidentiality associated with communication with a terminal that is incorrectly recognized can be further improved.

According to a fourth aspect of the present invention, in the security system of the first to third aspects, the terminal accommodating device includes first timer means for measuring a first cycle time, and the broadcast means includes the first timer means. It is characterized in that a request for updating the password including the password key data corresponding to the terminal is broadcast to the terminal at every cycle time.

That is, in the invention according to claim 4, the terminal accommodating device is provided with a first timer means, and the broadcast means sends a password update request at every first cycle time measured by the first timer means. I decided to broadcast all at once,
For example, even if the data in the memory built in the ONT is analyzed by malicious intent, it is necessary to further analyze the updated password, so that a decrease in confidentiality due to the identified password can be minimized, and security can be reduced. Can be enhanced.

According to a fifth aspect of the present invention, in the security system according to the fourth aspect, the terminal accommodating device includes second timer means for measuring a second cycle time, and the password transmission requesting means includes a second cycle time. Each terminal is required to transmit a password to each terminal.

That is, in the fifth aspect of the present invention, the terminal accommodating device is provided with a second timer means, and the password transmission request means sends the password to each terminal at every second cycle time measured by the second timer means. Since the password transmission request is made, the terminal that is incorrectly authenticated can be recognized even while the system is operating, and the security can be further improved.

According to a sixth aspect of the present invention, in the security system of the fifth aspect, the first and second timer means are provided corresponding to each of the connected terminals.

That is, in the invention according to claim 6, since the first and second timer means are provided corresponding to the terminal to be connected, it is possible to make a request for updating or transmitting a password according to the terminal. Thus, it is possible to configure an optimal system for reducing communication traffic and improving confidentiality. Further, the first terminal is also required for a conventional terminal that cannot respond to a password update request or a transmission request.
In addition, by setting the second cycle time to infinity, it is possible to coexist with a conventional terminal, and to realize a flexible system.

According to a seventh aspect of the present invention, in the security system of the third to sixth aspects, the terminal accommodating device is provided with a display unit for displaying a password update status for each terminal.

That is, according to the invention of claim 7, since the update status of the password can be displayed, the optimum system configuration by the network administrator can be realized as soon as possible, and the recovery in the event of a failure is promptly performed. Can be handled.

According to an eighth aspect of the present invention, in the security system of the first to seventh aspects, the terminal accommodating device and the plurality of terminals perform communication by an asynchronous transfer mode-passive optical network. .

That is, in the invention according to claim 8, a terminal installed on a subscriber side frequently turns on / off a power supply in an access network which is an application field where the security of data security in the terminal cannot be guaranteed. Since there is a high possibility that the password is changed or the installation location is moved, security can be improved by updating or verifying the password.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to embodiments.

FIG. 1 shows an outline of the configuration of an ATM-PON system to which a security system according to an embodiment of the present invention is applied. This security system comprises a plurality of first to N-th optical network units (Optica).
l Network Termination: hereinafter abbreviated as ONT. ) 20 ₁
~ 20 _N and Optical Line Terminator
ation: hereinafter abbreviated as OLT. ) 21.
The ONT20 ₁ ~20 _N and OLT21 first to N, the one-to-many connection via the optical fiber and the star coupler 22 has been performed. ONT20 ₁ ~20 _N of the first to N is assigned in advance unique serial number, respectively,
OLT21 is aware of the serial numbers of all ONT20 ₁ ~20 _N. The OLT 21 specifies the activated ONT by checking the serial number of each ONT at the time of activation. OLT 21 in this embodiment
Can check the password of each ONT based on the serial number and update the password not only at the time of startup but also at predetermined intervals. As a result, the ON that is erroneously recognized at startup is
T and subsequent communication are performed to avoid a significant decrease in the confidentiality of the communication information.

Here, in the ATM-PON system, O
LT21 is connected to the ATM network, each ONT20 ₁ ~20 _N
, A single-core bidirectional time-division multiplexing-time division multiple access (TimeDivision Multiplex-Time Division Multiple Ac
cess: Hereinafter, abbreviated as TDM-TDMA. ) Communication shall be performed. That is, the OLT 21 is provided with an A (not shown).
The ATM cell received from the TM network is multiplexed to generate a communication frame having a predetermined format. At this time, each AT
The arrangement information of the M cell to the frame is added.

FIG. 2 shows the security system shown in FIG.
Of the format configuration of communication frames transmitted and received by the
Is expressed. This communication frame 30 has a predetermined
A plurality of long time slots 31₁~ 31_L-1, 31_L~ 3
1_M(However, L ≦ M).
And two header information time slots 32 for control.
₁, 32_TwoIt has. ONT is an ATM network not shown
ATM cells received from these time slots 31₁
~ 31_MPlaced in one of At that time, the received AT
Referring to the destination information of the M cell,
Information indicating which destination ATM cell was allocated to the
Information to the header information time slot 32₁, 32_TwoPlace in
You. Time slot 32 for header information₁The first to the first
(L-1) ATM cell 31₁~ 31_L-1Corresponding to
Information is filled in. Time slot 32 for header information_Two
Include the L-th to M-th ATM cells 31_L~ 31_MCorresponding to
The arrangement information is entered. In addition, the same
For example, the synchronization bit is used for the time slot for header information.
To 32₁Fill in.

The frame to which such additional information has been added is transmitted to the O
Broadcast to all NT. For each ONT, OLT
The ATM cell addressed to itself is extracted with reference to the additional information added in (1). On the other hand, when transmitting communication information from the terminal to the ATM network, the transmission information assembled in the ATM cell is
In synchronization with the frame received from the LT 21, the transmission is performed at the transmission timing assigned to itself. Each cell transmitted at a different transmission timing from each ONT is
Received by the OLT 21. The OLT 21 transmits the ATM cells separated from the OLT 21 to an ATM network (not shown).
In this manner, one-core bidirectional TDM-TDMA communication is performed.

In the security system according to the present embodiment, the OLT 21 can periodically generate password key data for each ONT, and can transmit these to each ONT. In each ONT, a new password is generated from the received password key data and a pre-assigned unique serial number of each ONT. Hereinafter, the main components of the security system according to the present embodiment will be described with reference to FIG. Here, ONT20 ₁ ~20 _N of the first to N is assumed to have the same configuration, respectively.

[0031] The first of ONT20 ₁ is opposed to OLT2
An ONT-PON control unit 401 for performing PON communication control with the OLT ₁ and a message transmitting / receiving unit 41 ₁ for terminating and generating a message with the OLT 21.
The first ONT20 ₁ has ONT flash memory 42 _1, and is stored in the unique serial number for each pre-allocated ONT. Furthermore, the first ONT2
0 ₁ is the OLT 21 terminating in the message transmitting / receiving unit 41 ₁
Password forming portion 43 ₁ newly composing the password in accordance with the content of the message from a password reading unit 44 ₁ for reading the password stored newly constructed ONT flash memory 42 ₁ by the password forming portion 43 ₁ It has.

ONT-PON control section 40₁Is OLT2
The communication frame shown in FIG.
Detects synchronization bits contained in the frame. And this
Of a frame determined in advance based on the detection timing
Multiple header information tags assigned to a given location
Refer to the placement information entered in the
Time slot from the time slot of
Extract the received information of the user. This extracted reception information is
Message transmitting / receiving unit 41 as a received message ₁Sent to
Is done. Also, the ONT-PON control unit 40₁Is OLT
Based on the synchronization bits contained in the frame received from 21
The transmission timing assigned to the own device in advance
Message transmission and reception in synchronization with the transmission timing
Part 41₁Send outgoing message input from. Me
Message transmitting / receiving unit 41₁Is transmitted from OLT21
Password update request message in a predetermined format
Message or password transmission request message.
Analyze the contents of these request messages and convert them to request messages.
Extract the included information. Password composition unit 43₁Is
Message transmitting / receiving unit 41₁Password received by
Included in this extracted from the update request message.
Word key data and ONT flash memory 42₁
Of the first ONT 20₁Unique serial number
A new password is constructed from the issue number. This newly constructed
The generated password is stored in the ONT flash memory 42.₁
Is accumulated in Password reading unit 44₁Is the message
Transmitting / receiving unit 41 ₁Password sending request message by
Is received, the ONT flash memory 42₁To
Reads the stored password and displays it in a message.
Communication unit 41₁Pass to.

The OLT 21 has the first to Nth ONs facing each other.
Performs PON communication control between the T20 ₁ ~20 _N OLT-
The PON control unit 45, the first to _N ONT20 ₁ ~20 N
And a message transmission / reception unit 46 for terminating and generating a message between them. In addition, OLT 21
It has a LT flash memory 47, the ONT20 ₁ ~2
The password key data corresponding to 0 _N is stored.
The OLT 21 further generates a password key data to be transmitted to each ONT and a password control unit 48 for managing the password key data.
And a timer unit 49 for counting the update period of the password key data. Further, the OLT 21 is connected to a control terminal 50 that performs various settings for ATM-PON system control including setting and confirmation of a password.

The ONT-PON control unit 45 controls each ONT 2
0 ₁ receives each communication frame sent from to 20 _N, when it receives a predetermined reply message passes it to the message transceiver 46, otherwise sent to the ATM network (not shown). The message transmitting / receiving unit 46 is an OLT-PO
The contents of the predetermined reply message notified via the N control unit 45 are analyzed. Further, a password update request message and a password transmission request message which are transmitted at predetermined intervals are generated, and these are generated by the ONT-
This is transmitted to each ONT via the PON control unit 45. The password control unit 48 manages the password key data generated at predetermined intervals, and forms a new password from the serial number of each ONT recognized in advance in the same manner as the password configuration unit of each ONT. You can do it. Then, the password of each ONT notified by the reply message can be collated with the password. The timer unit 49 measures predetermined periods T ₁ and T ₂ , respectively. The password control unit 48 notified of the predetermined cycle by the timer unit 49 generates the password key data at each cycle T ₁ , performs a password transmission request at each cycle T ₂ , and performs password verification. Here, the cycle times T ₁ and T ₂ may be the same cycle time or different cycle times. It is appropriately selected according to the number of ONTs to be connected and the processing capability of the OLT.

In the security system having the above-described configuration, a new password is generated from the pre-assigned unique serial number of each ONT and the password key data generated by the OLT 21. This is OL
By sending a password key data realized by performing the password update request for every predetermined period T ₁ from T21. Furthermore, the ON further in every cycle T ₂ are OLT21
The password is collected by transmitting a password updated at that time from T, and the password is collected and collated with a newly constructed password unique to the OLT 21 to improve security. When it is determined by the comparison that there is no match, the OLT 21 immediately stops communication with the ONT.

The OLT 21 that enables such a password update request and password collation control is provided with a central processing unit (Central Processing Unit:
Abbreviated as U. ) Based on a program stored in a predetermined storage device such as an external storage device such as a magnetic disk or a read only memory (hereinafter abbreviated as ROM) provided separately therefrom. Various controls can be executed.

FIG. 3 shows an outline of the processing contents of the password update request program stored in such a storage device. First, the course of the period T ₁ by the timer section 49 monitors (step S60), when this is detected (step S60: Y), to produce a new password key data for each ONT in the password control unit 48 (Step S61). This may be a random number or a function output corresponding to the current time. Here, it is assumed that for example to produce a "35" as the password key data corresponding to the first ONT20 _1. The password key data generated by the password control unit 48 is
It is stored in the OLT flash memory 47 corresponding to each ONT (step S62). Next, the message transmitting / receiving unit 46 is caused to create a password update request message (step S63). As such a password update request message, a format of a communication message in communication of a normal ATM-PON system is used.

FIG. 4 shows an outline of the format configuration of such a communication message. That is, A
I as a communication message in the TM-PON system
TU-T Recommendation G. The message recommended in 983 includes message type information 66 for identifying the type of the message at a predetermined position of a predetermined message 65.
And an ID that identifies which ONT is involved in the communication
It has information 67 and message contents 68 to be filled in according to the type of message.

Therefore, the password update request message generated in step S63 of FIG.
When generating 20 ₁ addressed, the message type 66 fills a pre-assigned identification information to identify the password update request message. The ID information 67 contains the first O
NT20 ₁ to write the serial number that is unique to the assignment. For the message content 68, the password key data generated by the password control unit 48 is entered in the password update request message. Such password update request message is generated for each full ONT20 ₁ ~20 _N, it sent multiplexed to a communication format shown from OLT-PON control unit 45 in FIG. 2 (step S69). Here, a password update request message is also sent to ONTs that have not been authenticated at the time of system startup.
Authenticate as T. Then, to monitor the course of the period T ₁ again (return).

At step S60, the period T₁Monitor the progress of
If this is not detected (step S60: N),
Period T_TwoIs monitored (step S70). Here around
Period T_TwoIs detected (step S70: Y),
Path corresponding to each ONT to the message transmitting / receiving unit 46
A word transmission request message is created (step S7).
1). As the password transmission request message,
A communication message having the format shown in FIG.
The password transmission request message is transmitted to the first ONT 20 ₁Addressed to
If the message type 66 is generated
The knowledge assigned in advance to identify the transmission request message
Fill in other information. The ID information 67 includes the first ONT 20
₁Enter the serial number that is uniquely assigned.
For message content 68, a password transmission request
Nothing is specified in the message. Such password transmission
The communication request message includes all ONT20₁~ 20_NGenerate for each
The OLT-PON control unit 45 transmits the communication shown in FIG.
The data is multiplexed in the format and transmitted (step S7).
2). Here, ON which was not authenticated at system startup
Send password transmission request message to T
Depending on the password verification result, a new startup ONT
Authenticate as After that, the cycle T₁Monitor the progress of
(Return).

[0041] monitors the elapse of the period T ₁ in step S60, does not detect this (step S60: N), the period T ₂
Monitoring the course of (step S70), when not detecting it: (step S70 N) monitors the elapse of the period T ₁ again (return).

The password update request message and the password transmission request message generated by the OLT 21 are received by each ONT. Each ONT receiving the password update request message updates the password. Each ON that received the password transmission request message
T sends the password to the OLT 21 in the reply message.

The ONT 20 ₁ that enables such control
To 20 _N each have a CPU (not shown),
Various controls can be executed based on a program stored in an external storage device such as a magnetic disk or a predetermined storage device such as a ROM provided separately therefrom. Here, a description will be given first ONT20 ₁ for.

[0044] Figure 5 shows an outline of the processing contents of the message reception processing program in the first ONT20 ₁ stored in such storage devices. First, OL
Monitors the reception of the password update request message from the T21, when receiving this: (step S80 Y) is to read the respective ONT unique serial number stored in the ONT flash memory 42 ₁ (step S8
1), supplied to the password configuration section 43 _1. At the same it is determined that the password update request message by the message transmission and reception unit 41 ₁ at the same time, the password key data generated by the password control unit 48 is extracted as the message content, it is supplied to the password configuration unit 43 _1.
Password component 43 ₁ comprises a first ONT20 ₁ serial number, along with the password key data notified along with the password update request message, constitute a new password (step S82). The configuration method is not limited, and any configuration method can be used as long as the OLT 21 can achieve the same result. Here, for example, it is assumed that the above-mentioned password key data “35” indicates that “the third bit and the fifth bit of the serial number are exchanged”. This is O
A new password is similarly configured in the LT 21. Password configured in this way, the password is updated is stored in the ONT flash memory 42 ₁ (step S83). Thereafter, the reception of the password update request message from the OLT 21 is monitored again (return).

If the reception of the password update request message from the OLT 21 cannot be detected in step S80 (step S80: N), the reception of the password transmission request message from the OLT 21 is monitored (step S84).
When this is detected: (step S84 Y) causes read the password stored in the password reading unit 44 ₁ in the ONT flash memory 42 ₁ (step S8
5). Then, the message transceiver ₄₁₁ to generate a return message format shown in FIG. 4 (step S86). In this reply message, identification information assigned in advance to identify the reply message to the password transmission request message is entered in the message type 66. The ID information 67 to write the serial number assigned to the first ONT20 ₁ specific. The message content 68, to fill the updated in the first ONT20 ₁ should be returned password. ONT-PON control unit 40 _1, a reply message to such password transmission request message, ONT20 advance first the basis of the synchronization bits included in the received information from the OLT21
_It is assigned to ₁ and transmitted to the OLT 21 at the transmission timing (step S87). Then again OLT2
1 to monitor the reception of the password update request message (return).

If the reception of the password update request message is not detected at step S80 (step S80: N), and the reception of the password transmission request message is not detected at step S84 (step S84: N), O is reset again.
The reception of the password update request message from the LT 21 is monitored (return).

A reply message from each ONT to the password transmission request message generated by the OLT 21 is returned to the OLT 21. And OLT21 is
The password included in these reply messages is checked against a password uniquely configured from the serial number provided in the own device. Such OLT 21 is performed according to the password collation program as described above.

FIG. 6 shows an outline of the processing contents of the password verification program stored in the storage device (not shown) of the OLT 21. That is, the OLT 21 is ON
The reception of a reply message to the password transmission request message from T is monitored (step S90: N, return). When this is detected (step S90: Y), the reply message is included in the reply message received by the message transmitting / receiving unit 46. The password is extracted, the password key data stored in the OLT flash memory 47 corresponding to each ONT is read out, and the password is compared with the newly formed password in the password control unit 48 in the same manner as in each ONT. Perform (Step S91). As a result of this collation, when they match, it is determined that they match (step S92: N), and the reception of the next reply message is monitored as it is (return). On the other hand, if the two do not match as a result of the collation, it is determined that they do not match (step S92: Y), and an error message is generated and notified to the OLT-PON control unit 45 (step S93). Then, the OLT-PON control unit 45 notified of the error message stops only data transmission to the ONT in which such a password mismatch has occurred (step S94). Thereafter, reception of the next reply message is monitored again (return).

As described above, in the security system according to the present embodiment, in a communication system in which a plurality of ONTs are connected one-to-many to the OLT and broadcast to each ONT, the OLT is The password key data is generated corresponding to the ONT, and the password is updated for each ONT using the generated password key data. In each ONT, the password key data notified together with the update request and the
A new password is configured based on the serial number uniquely assigned to NT. As a result, each O
As a result of maliciously analyzing the data in the memory incorporated in the NT or the like, it is possible to prevent the security of the communication information from being reduced due to the analysis of the password, thereby improving the security. In addition, the OLT sends a password transmission request message to each ONT at each cycle, and sends a password transmission request message to each ONT.
The password of T was collected and collated. As a result of collation, if there is no match, only transmission to the corresponding ONT is stopped. As a result, the password is updated one after another a plurality of times, so that it becomes difficult to analyze the password by malicious intent, and the security can be further improved.

In the security system according to the present embodiment, the ATM-
The case of application to the PON system has been described.
It is not limited to the TM-PON system.

In the security system according to the present embodiment, the OLT stores the password key data generated for each ONT, and configures a new password only by changing the password key data from a unique serial number. ing. This is because the recovery process at the time of password mismatch is easy. But OL
At T, it is possible to further enhance security by storing a newly constructed password with this password key data and sequentially updating this password based on the previously constructed password.

In the security system according to this embodiment, the control terminal 50 connected to the OLT 21
In many cases, the LT 21 is installed in a remote location different from the installation location. Therefore, it is ON even at the place where the OLT 21 is installed.
The OLT 21 may be provided with a display unit for displaying a timer update cycle or the like for confirming the authentication status of T or the like.

In addition, ITU-T Recommendation G. 983 specifies the numbering method of the ONT serial number as a password at the time of activation, but in the ATM-PON system to which the security system according to the present embodiment is applied, O.
The password is updated at each update cycle of the timer unit provided on the LT side. Therefore, there is no need to use the ONT serial number as the password at the time of startup, and any value may be used as long as the OLT recognizes the password uniquely assigned to each ONT. That is, even if an arbitrary value is set as the password at the time of activation, it is possible to avoid a decrease in confidentiality.

Further, by making the set time of the timer unit 49 infinite, the ITU-T Recommendation G. The present invention can also be applied to a system in which a password is fixed at the time of startup specified in 983.

In the security system according to the present embodiment, the timer unit 49 issues a password update and transmission request to all ONTs every common cycle, but the present invention is not limited to this. For example, the OLT is provided with a timer corresponding to each ONT, and the ONT according to the present embodiment having a password update function and the ITU-T Recommendation G.
Even in a system in which a conventional ONT conforming to 983 is mixed, a password is updated at a password update cycle individually set for each ONT having a password update function, while a timer set time is set for the conventional ONT. It can be easily applied by setting it to infinity. This can be easily set by the control terminal 50 connected to the OLT 21, and the provision of the display means makes it easy to check the update status.

[0056]

As described above, according to the first aspect of the present invention, each terminal uses the password key data for each terminal generated by the terminal accommodating device based on the terminal number of the terminal itself and each password key data. By newly constructing a password, as a result of maliciously analyzing the data in the memory built in each terminal, etc., it is possible to prevent a decrease in confidentiality of communication information due to password analysis and improve security .

According to the second aspect of the present invention, in addition to the effects of the first aspect of the present invention, the terminal password is collected by the terminal accommodating device and collated with the independently generated password, so that an erroneous operation is performed. Accurately recognize terminals due to recognition and maliciousness, and improve the security of the entire system.

Further, according to the third aspect of the present invention, communication with a terminal that is erroneously recognized can be immediately stopped to further improve confidentiality.

According to the fourth aspect of the present invention,
Even if the data stored in the memory included in the ONT is analyzed by malicious intent, it is necessary to analyze the updated password. Therefore, it is possible to minimize the decrease in confidentiality due to the identified password and to enhance the security. be able to.

Further, according to the fifth aspect of the present invention, a terminal that has been erroneously authenticated can be accurately recognized even while the system is operating, and confidentiality is further enhanced.

Further, according to the invention of claim 6, it is possible to make a request for updating or transmitting a password in accordance with the terminal, and to constitute an optimal system for reducing communication traffic and improving confidentiality. be able to. In addition, even for a conventional terminal that cannot respond to a password update request or a transmission request, the first and second cycle times are set to infinity, thereby enabling coexistence with the conventional terminal and flexibility. A certain system can be realized.

According to the seventh aspect of the present invention, the update status of the password can be displayed, so that the optimum system configuration by the network administrator can be realized as soon as possible, and the recovery in the event of a failure can be prevented. Can respond quickly.

Further, according to the invention described in claim 8,
In an access network where the confidentiality of data in the terminal cannot be guaranteed, there is a possibility that the terminal installed at the subscriber side is frequently turned on / off or the location is moved. , The security can be improved by updating or verifying the password.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an outline of a configuration of an ATM-PON system to which a security system according to an embodiment of the present invention is applied.

FIG. 2 is an explanatory diagram showing an outline of a format configuration of a communication frame in the embodiment.

FIG. 3 is a flowchart showing an outline of the contents of a password update request process in the embodiment.

FIG. 4 is an explanatory diagram showing an outline of a format configuration of a communication message in the embodiment.

FIG. 5 is a flowchart showing an outline of the contents of a message receiving process in the embodiment.

FIG. 6 is a flowchart showing an outline of the contents of a password collation process in the embodiment.

FIG. 7 is an explanatory diagram showing an outline of a configuration of a conventional ATM-PON system.

[Explanation of symbols]

201 _{1 to} 20 _N First to Nth ONTs 21 OLT 22 Star coupler 40 ₁ ONT-PON control unit 41 ₁ , 46 Message transmission / reception unit 42 ₁ ONT flash memory 43 ₁ Password configuration unit 44 ₁ Password read unit 45 OLT-PON Control unit 47 OLT flash memory 48 Password control unit 49 Timer unit 50 Control terminal

Claims (8)

[Claims] 1. A password key data generating means for generating password key data for each connected terminal, and a request for updating a password including the password key data generated by the password key data generating means is sent to the terminals simultaneously. A terminal accommodating device having a broadcasting unit for broadcasting, a password key data extracting unit for extracting password key data of the own terminal from a password update request broadcasted by the broadcasting unit, and a terminal uniquely assigned in advance. A security system comprising: a plurality of terminals each including a number and a password updating unit that updates a password based on the password key data extracted by the password key data extracting unit. 2. A password key data generating means for generating password key data for each connected terminal, and a request for updating a password including the password key data generated by the password key data generating means is sent to the terminals simultaneously. Broadcasting means for reporting, password transmission requesting means for requesting transmission of a password for each terminal, and password key data generated by the password key data generating means and a terminal number pre-assigned uniquely to the terminal. Password generating means for generating a password in response to the password transmission request means, and a password matching means for matching the password received from each of the terminals with the password generated by the password generating means for each terminal. Terminal accommodating device Password key data extraction means for extracting the password key data of the own terminal from the password update request broadcast by the means; and a terminal number uniquely assigned in advance and the password key data extracted by the password key data extraction means. A plurality of terminals including a password updating unit for generating a password based on the password, and a password returning unit for returning a password of the own terminal when the transmission of the password is requested by the password transmission requesting unit. Security system. 3. The terminal accommodating device stops transmission to a terminal whose password is inconsistent when it is determined that the password received by the verification unit and the password generated by the password generation unit are inconsistent. 3. The security system according to claim 2, further comprising transmission stop means. 4. The terminal accommodating device includes first timer means for measuring a first cycle time, and the broadcast means includes a password including password key data corresponding to the terminal for each first cycle time. 4. The security system according to claim 1, wherein an update request is broadcast to the terminal. 5. The terminal accommodating device includes second timer means for measuring a second cycle time, and the password transmission request means transmits a password to each of the terminals at every second cycle time. The security system according to claim 4, wherein the request is issued. 6. The security system according to claim 5, wherein said first and second timer means are provided for each of said terminals to be connected. 7. The security system according to claim 3, wherein said terminal accommodating device includes display means for displaying an update status of a password for each terminal. 8. The security system according to claim 1, wherein the terminal accommodating device and the plurality of terminals perform communication by an asynchronous transfer mode-passive optical network.