JP2003198636A - Security system for network and its security method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high level security system and method for preventing the illegal access of an internal network connectable through a wide area network to the outside to electronic equipment. <P>SOLUTION: As long as proper access from an external network to the prescribed electronic equipment of an internal network is required, the security device of the internal network generates a connection instruction, and a switch means set on a network line connecting the electronic equipment to the side area network establishes the physical connection of the network line according to the connection instruction. When any access is not required, the switch means holds the connection of the network line in the physically released state. Thus, it is possible to provide a high level security system and method capable of preventing any illegal access by a hacker or the like. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a security system and a security method for preventing unauthorized access to electronic equipment in an internal network connected to a wide area network.

[0002]

2. Description of the Related Art Conventionally, a company's network is an internal network closed within the company (LAN or other dedicated line)
, Which has been constructed with a secure network that is not exposed to outside users or connections from unspecified users. However, due to the development and popularization of wide area networks (Internet and other computer networks that cover almost the entire world) in recent years, from the internal network to the outside (home, business trip destinations, remote offices and other internal networks) via the wide area network. It has become common to connect to a certain communication base) or to connect to the internal network from the outside.
Also, in general households, various services such as the use of electronic mail, the exchange of various information, and the remote control of information appliances can be used by connecting to the outside via the Internet.

However, by connecting to the outside through a wide area network, communication for the purpose of acquisition, provision, exchange and the like of information resources becomes possible and the convenience of the network is improved, while computer virus infection and hackers are made. The so-called network crimes due to the unauthorized access of the above have frequently occurred, and the problem of insufficient security for countering such crimes has become remarkable. As countermeasures against these, for example, firewalls, encryption techniques, access control systems, and antivirus software have been developed. In particular, the problem of unauthorized access by a hacker or the like is important because it may cause serious damage due to leakage, falsification, loss, etc. of confidential data of a company or the like, and many means for preventing these have been proposed. For example, Japanese Patent Laid-Open No. 2001-519
In Japanese Patent Publication No. 48, access to the access permission content specified by the user from an electronic device or service on an external electronic device network under different management is accessed only when the permission condition specified by the user is satisfied in the electronic device network. There is disclosed an access control system for generating an access acceptance program for accessing an access destination by accepting and relaying the request in response to a request from the user.

Here, an example of a network security system in the prior art will be described. FIG. 5 is a block diagram showing an outline of a security system configuration according to a conventional technique. In the figure, the internal network 51 is
It is connected to the wide area network 50. Usually, a plurality of electronic devices 54a-54n to be accessed from the outside are connected to the internal network 51, and each remote user (including electronic devices used by the user) 52a-52.
n is a computer network (not shown) to which it is connected, a wide area network 50, and an internal network 5.
It is possible to communicate with each of the electronic devices 54a-54n via 1 or the like. The access control device 53 controls each remote user 52a-5.
Wide area network 50 to control access from 2n
And the internal network 51 are connected to each other. The access control device 53 also controls the remote users 52a-52.
Access is accepted only when the access request of n satisfies the access permission condition designated in advance. Therefore, when the legitimate users 52a-52n require access from the outside, access is possible under predetermined access permission conditions, while unauthorized access that does not satisfy the access permission conditions is denied. Access is properly controlled.
In order to improve the security level regarding particularly important corporate information, the access permission conditions here are similar to those in other related arts, rather than relatively simple ones such as simple authentication of a user or a sender. Rather, there are many that include extremely complicated procedures.

[0005]

However, in such a conventional technique, it is considered that access can be restricted and constant unauthorized access can be suppressed by setting various access permission conditions or performing complicated procedures. However, it is a countermeasure (hereinafter referred to as logical security) that uses only a logical (soft) method, and the physical (hardware) network line is always connected. It is considered that the environment is still accessible if you carry it. In addition, in these logical security, the procedure of access permission becomes very complicated in order to improve the security level, and the constituent devices of the system for realizing the complicated procedure are required to have various functions. Cost tends to increase.

In order to solve these problems, the present invention provides an internal connection between an electronic device and a wide area network only when an appropriate external access to the specified electronic device in the internal network is required. It is an object of the present invention to provide an advanced security system that can prevent unauthorized access by hackers by connecting network lines. In addition, an object of the present invention is to make the device configuration of the security system relatively simple and to realize it at low cost.

[0007]

In order to achieve the above object, the security system of the present invention provides an internal network including an electronic device capable of communicating with the outside via a wide area network, and a signal between the electronic device and the outside is transmitted. A security system for transmission and reception, which is security for outputting a connection signal or a release signal to the switch means provided on an internal network line for connecting an electronic device and a wide area network A device, the switch means being in an on state (that is, a switch closed state) in response to a connection signal and being in an off state (that is, a switch open state) in response to a release signal. .

Also, the security device receives a connection request for an electronic device from a remote user via a wide area network, and generates a connection signal only when the connection request satisfies a predetermined connection permission condition. It is characterized by having a control unit.

Alternatively, the security device has a security program for repeatedly generating a connection signal and a release signal.

Therefore, only when the connection is required, the physical connection of the internal network line connecting the wide area network and the desired electronic device is established, and the user accesses the electronic device to execute the intended task. can do. In addition, since the state of establishing and releasing the physical connection to each electronic device by the switch means cannot be predicted by a hacker or the like, the difficulty of unauthorized access is significantly improved, and access with high flexibility and high security level is achieved. Control is realized.

The present invention is also a security method for transmitting and receiving signals between an electronic device and the outside in an internal network including the electronic device capable of communicating with the outside via the wide area network. A step of providing a switch means on the internal network line for connecting the electronic device and generating a connection signal for establishing a connection between the electronic device and the wide area network;
A process of turning on the switch means in response to the connection signal, a process of generating a release signal for releasing the connection between the electronic device and the wide area network, and an off state of the switch means in response to the release signal. There is provided a network security method including the following steps.

Further, the process of generating the connection signal is executed only when a connection request to the electronic device is received from a remote user through the wide area network and the connection request satisfies a predetermined connection permission condition. It is characterized by being done.

Alternatively, the step of generating the connection signal is performed according to a security program for repeatedly generating the connection signal and the release signal.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a block diagram showing the outline of the configuration of a security system 19 according to an embodiment of the present invention. In FIG. 1, the internal network 11 is connected to the wide area network 10 so as to be able to communicate with the outside. The electronic devices 14a and 14b are objects to be accessed by an external remote user.
Computers, monitors and printers in corporate offices, control devices and sensors in production lines, etc., host computers and database servers thereof,
Examples include information home appliances in general households and other electric appliances having a communication function. Here, the equipment sequencer 14a and the line monitoring device 14b in the network of the production system are shown. Here, the term “user” in the present specification is not limited to so-called human operators, but also includes any electronic device that is automatically controlled and is capable of network communication. In the security device 13, as will be described later with reference to FIG. 2, a connection control unit that generates a connection signal (in some cases, a release signal) relating to an electronic device in response to a request from a user, and normally, a connection signal and a release signal are normally and repeatedly generated. And a security program having a predetermined connection / disconnection signal generation condition for performing. The connection signal and the disconnection signal can be generated temporarily or continuously depending on the type of the switch means on the receiving side. Further, the security device 13 may additionally have a gateway function. In this embodiment, the security device 13
1 is located in the vicinity of the connection to the wide area network 10 and the internal network 11 as shown in FIG. 1, but it can be installed at any place as long as it can communicate with a remote user via the wide area network. Further, in the network line 15 constituting the internal network, the line route is shown so that the electronic device can be accessed from the outside without passing through the security device 13.
Like the access control device shown in FIG.
It is also possible to configure the electronic device to be accessed via the device 3 once and add a further access control function to the security device.

Switch means 16a, 16b respectively provided on the internal network lines connecting the equipment sequencer 14a and the line monitoring device 14b to the wide area network.
Can receive the connection signal output from the security device 13 and physically connect the internal network line. In some cases, the switch means 16a, 16b can also receive the release signal from the security device 13 to physically release the network line. Examples of the switch means include a general-purpose relay regardless of whether it is a contact type or a non-contact type, and a switch that operates in response to a predetermined input signal to control an electric circuit. Here, a normally open type contact is used. Each of the photo MOS relays having the configuration is shown. The photo-MOS relay is suitable because it has features such as long life and low drive input, and has no moving parts or contact parts, so that problems of wear do not occur. Further, by making the contact structure a normally open type, it is possible to normally keep the network connection released and establish the connection only when a connection signal is received from the security device 13.

Although the case where one switch means is provided corresponding to each electronic device as the simplest configuration is shown here, a plurality of switches are provided on the internal network line connecting the wide area network and the electronic circuit. It is also possible to arrange means and combine them to establish and release the connection.

FIG. 2 shows the security device 1 shown in FIG.
It is a block diagram of 3. The security device 13 includes a connection control unit 21 that can receive a connection request from a remote user to a predetermined electronic device, determines whether the connection to the electronic device is appropriate based on a predetermined connection permission condition, and makes a connection request. Generates a connection signal for the electronic device when the connection permission condition is satisfied. Here, the connection permission conditions include, for example, user identification information including a password, sender identification information,
It includes conditions related to access target designation and execution task content, and a legitimate user can send a connection request so as to satisfy these conditions. The connection control unit 2
As for the function 1 and the connection permission condition, a simpler function can be applied as compared with the function and the access permission condition of the above-described logical security access control device, but the function and the connection permission condition are limited to those mentioned in this specification. However, it is possible to use, for example, those well-known to those skilled in the art, which are used for network access control including conventional techniques.

In addition, the security device 13 has a connection / disconnection predetermined by the administrator of the security system to generate a connection signal and a release signal for the electronic device.
Security program 22 having release signal generation condition
And generating a connection signal or a disconnection signal relating to a predetermined electronic device according to the connection / release signal generation condition.
The connection / release signal generation condition includes, for example, the identification number of the electronic device to be accessed, the connection timing, and the connection holding time, and the connection permission of the user based on the connection adequacy determination by the connection control unit as described above. Be done.

In one connection operation, a connection signal (in some cases, a release signal) is generated in accordance with either the connection control unit 21 or the security program 22 described above. However, the two do not necessarily have to be operations in separate access. For example, the administrator of the security system presets the priority between the security program and a predetermined user, so that the priority of the two is high. It is also possible for one to interrupt the operation of the other and to intervene. Hereinafter, FIG. 3 shows an access procedure including a connection signal generation process by the connection control unit 21, and FIG. 4 shows an access procedure including a connection signal generation process according to the security program 22.

FIG. 3 is a flowchart showing an access procedure to the internal network including the security system according to the embodiment of the present invention. In step 101,
The security device receives a connection request from a remote user to an electronic device to be accessed. In step 102, the security device determines whether or not the connection request satisfies a predetermined connection permission condition, and if so, the process proceeds to step 103 to generate a connection signal for the electronic device. In step 104, the switch means installed on the internal network line between the wide area network and the electronic device to be accessed receives the connection signal,
The physical connection of the network line is established according to the connection signal. In step 105, the user accesses the electronic device to perform the desired task. The tasks here include input / output of various commands to / from electronic devices and transmission / reception of information such as data, voice, and images. After completion of the task, in step 106, the security device receives a release request from the user to the electronic device and generates a release signal for the electronic device. Finally, in step 107, the switch means receives the release signal of the security device, releases the connection of the network line connecting the wide area network and the electronic device in accordance with the release signal, and the series of access procedures ends.

Regarding the disconnection of the internal network line, the normally open type photo M shown in FIG.
When an OS relay or the like is used as the switch means, the connection signal is stopped after the task is completed (for example, when the task is completed, the electronic device has a function of signaling the security device to complete the task, so that the connection signal is generated. Since it can be stopped), the state is released at the same time, and therefore the generation and process of the release signal by the release request as shown in step 106 can be omitted. Further, although not shown in the present embodiment, a general user authentication means may be provided in the electronic device for the remote user's access to the desired electronic device after the network connection is established.

FIG. 4 is a flow chart showing an access procedure to an internal network including a security system in another embodiment of the present invention. In step 201, the administrator of the security system prepares a security program including a predetermined connection / release signal generation condition for generating a connection signal relating to the electronic device to be accessed. In step 202, the security device generates a connection signal according to the connection / release signal generation condition of the security program. Steps 203 and 204 are similar to steps 104 and 105 of FIG. 3, respectively, but step 2
In 04, the user needs to execute the task in accordance with the connection / disconnection signal generation condition of the security program. Therefore, when a remote user accesses, for example, an electronic device that is under the same security management as the access target and is automatically controlled to execute a task in accordance with a predetermined connection / release signal generation condition of a security program Can be used. This is a case where, for example, production systems of one company that are separated from each other communicate with each other, and an electronic device in the internal network as shown in FIG. 1 is connected to an external electronic device having a similar configuration in a wide area network. This corresponds to the case of systematically communicating via.
The disconnection of the internal network line is the same as in the case of FIG. 3 described above.

The present invention is not applied to the use of the Internet by ordinary households in which constant connection is the basic form of network connection, but rather the constant connection of exchange of various information resources in enterprises and home appliances for remote control of ordinary households. Is suitable for connection to an internal network that does not necessarily require. For example, in a company that has offices and production bases all over the world, they communicate with each other via a wide area network as needed, which corresponds to this, and it is possible to exchange information at a high security level. It is also useful for management and analysis of production data in the management department, and for equipment diagnosis and remote maintenance in the equipment department.

While we have described specific embodiments of the present invention, it will be apparent to those skilled in the art that numerous other embodiments can be constructed using the principles of the invention.

[0026]

As described above, according to the present invention, the electronic device and the wide area network are switched by the switch means only when appropriate access is required from the outside to the predetermined electronic device in the internal network through the wide area network. While physically connecting the internal network line that connects with, if the connection is unnecessary, it is possible to reliably prevent unauthorized access by hackers by physically disconnecting the network line, It is possible to provide an advanced security system and security method. In addition, according to the present invention, the security level can be improved without requiring a complicated procedure for access from the outside, so that the system configuration becomes relatively simple and high security can be realized at low cost.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a system according to an embodiment of the present invention.

FIG. 2 is a diagram showing the configuration of the security device shown in FIG.

FIG. 3 is a flowchart showing a procedure of accessing an electronic device of an internal network in an embodiment of the present invention.

FIG. 4 is a flow diagram showing a procedure of accessing an electronic device of an internal network according to another embodiment of the present invention.

FIG. 5 is a block diagram showing an outline of a configuration of a network security system in a conventional technique.

[Explanation of symbols]

Wide area network 11,51 Internal network 13 Security device 14a, 14b Electronic device 15,55 network lines 16a, 16b switch means 19 Security system 21 Connection control unit 22 Security Program 52a-52n Remote user 53 Access control device 54a-54n Electronic equipment

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 5B085 AE00 BC00                 5B089 GA04 KA17 KB13 KG10                 5K030 GA15 HD01 HD06 LD20                 5K033 AA08 CB08 DA06 DB18

Claims (8)

[Claims] 1. A security system against exchange of signals between an electronic device and the outside in an internal network including an electronic device capable of communicating with the outside via a wide area network, the electronic device and the wide area network. A switch device provided on the internal network line to connect the switch and a security device that outputs a connection signal or a release signal to the switch device, wherein the switch device responds to the connection signal. A network security system, which is turned on and turned off in response to the release signal. 2. The security device receives a connection request to the electronic device from a remote user via the wide area network, and generates a connection signal only when the connection request satisfies a predetermined connection permission condition. The network security system according to claim 1, further comprising a connection control unit that performs the connection control. 3. The network security system according to claim 1, wherein the security device has a security program including a connection / release signal generation condition for repeatedly generating the connection signal and the release signal. . 4. The network security system according to claim 1, wherein the switch means has a normally open contact structure. 5. A security method for transmitting and receiving signals between an electronic device and the outside in an internal network including an electronic device capable of communicating with the outside via a wide area network, the wide area network and the electronic device A switch means is provided on the internal network line to connect the switch and the switch means for generating a connection signal for establishing a connection between the electronic device and the wide area network; And a step of generating a release signal for releasing the connection between the electronic device and the wide area network, and a step of turning off the switch means in response to the release signal. Network security method characterized by. 6. The process of generating the connection signal is executed only when a connection request to the electronic device is received from a remote user via the wide area network, and the connection request satisfies a predetermined connection permission condition. The network security method according to claim 5, wherein: 7. The method according to claim 5, wherein the step of generating the connection signal is executed according to a security program including a connection / release signal generation condition for repeatedly generating the connection signal and the release signal. Network security methods. 8. The network security method according to claim 5, wherein the switch means has a normally open contact structure.