CN101800649A - Physical isolation card - Google Patents

Physical isolation card Download PDF

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Publication number
CN101800649A
CN101800649A CN 201010124645 CN201010124645A CN101800649A CN 101800649 A CN101800649 A CN 101800649A CN 201010124645 CN201010124645 CN 201010124645 CN 201010124645 A CN201010124645 A CN 201010124645A CN 101800649 A CN101800649 A CN 101800649A
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CN
China
Prior art keywords
main control
control unit
unit
network
physical isolation
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Pending
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CN 201010124645
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Chinese (zh)
Inventor
胡必雄
肖继红
刘焕宗
厉义民
王平
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WUHAN HUAYUAN ELECTRIC POWER GROUP CO Ltd
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WUHAN HUAYUAN ELECTRIC POWER GROUP CO Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Priority to CN 201010124645 priority Critical patent/CN101800649A/en
Publication of CN101800649A publication Critical patent/CN101800649A/en
Pending legal-status Critical Current

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Abstract

The invention discloses a physical isolation card, which comprises a main control unit, a power interface unit, a cable network switching unit, a disk switching unit, a communication unit and a radio control unit. The main control unit receives an external instruction through the communication unit and generates a control signal according to the instruction, and the power interface unit supplies electricity to the main control unit; the cable network switching unit performs inside-outside network switching on a cable network according to the control signal of the main control unit; the disk switching unit selects a disk corresponding to the inside-outside network according to the control signal of the main control unit; the radio control unit controls the on-off state between a wireless local area network card and a computer according the signal of the main control unit; and an input end of the radio control unit is connected with the main control unit, and an output end is connected between a communication interface for interconnecting the computer and the wireless local area network card. The physical isolation card not only supports the cable network, but also supports the wireless network, so that physical isolation between an inside network and an outside network is realized; and the structure is simple and application and arrangement cost is low.

Description

Physical isolation card
Technical field
The present invention relates to the network information security technology field, relate in particular to a kind of network security physical isolation card.
Background technology
Current electronic information technology development is swift and violent, and Computer information network has covered each field of society.On the one hand, network provides resource-sharing, has improved the reliability of system, has improved operating efficiency by the load of spreading the work, and has had expandability.On the other hand, also increased the fragility and the complexity of network security, resource-sharing has increased the possibility that network is compromised and attack.Malicious attacker can adopt various means to carry out destructive activity, information security has been constituted great threat, particularly in enterprises and institutions such as office, government, banks, its internal information or to relate to secret, secret data be not wish to be stolen by the user of outer net, in case the information security accident takes place, will can produce huge negative benefit socially, lead to the heavy losses of enterprise even national interests.
Because features such as the complexity of computer network architectures and opening thereof, the safety of the network equipment and data become the major issue that influences the normal operation of network.Up to the present, also without any a kind of Network Security Device of the logic mechanism safety of guarantee information system fully independently.In this case, the physical isolation technology is arisen at the historic moment.So-called physical isolation is meant that the terminal use can use in-house network and the Internet simultaneously, adopts network to switch back internal lan and external the Internet isolation, does not promptly have physical path between local area network (LAN) and the Internet, thereby really guarantees the safety of network.Inside and outside network physical is isolated a link in the security assurance information system as a whole, and it is to solve classified network at present and public network is isolated from each other, and avoids the safest, the effective method of information leakage.
Existing physical isolation technology mainly comprises following two kinds:
1) adopts the dual network system.Promptly dispose two and overlap independently network system, wherein a cover is in-house network, connects inner computer, realizes internal data, information sharing etc.; Another set of is extranets, with Internet connection.Simultaneously, at user terminal configuration two computers, this situation investment is excessive.
2) special network isolating device is installed on subscriber computer, is realized the physical isolation of inside and outside net by this network isolating device.As the patent No. is that the Chinese patent of 200520057156.X discloses a kind of network isolating device based on pci bus, and it is by switching the cable network port and selecting corresponding with it hard disk to realize the physical isolation of intranet and extranet.
Existing computer physics spacer assembly all is to isolate at cable network, along with further developing of network technology, the application of wireless network more and more widely only can not have been satisfied the inside and outside network physical isolation of prior art development with the computer physics spacer assembly of aforementioned type.Therefore, demand providing a kind of urgently and have the physical isolation card of wireless network isolation features to overcome above-mentioned defective.
Summary of the invention
The technical problem to be solved in the present invention is to provide a kind of physical isolation card, this physical isolation card not only supports cable network to isolate, also possess the wireless network isolation features, thereby can effectively realize the physical isolation of intranet and extranet, it is simple in structure and the application deployment cost is low.
In order to solve the problems of the technologies described above, the invention provides a kind of physical isolation card, it comprises main control unit, power interface unit, cable network switch unit, hard disk switch unit, communication unit and wireless energy control units.Described main control unit is used to receive external command and produces control signal according to the instruction that receives.Described power interface unit is used to described main control unit power supply.Described cable network switch unit is used for according to the control signal of described main control unit cable network being carried out intranet and extranet and switches.Described hard disk switch unit is used for selecting and the corresponding hard disk of intranet and extranet according to the control signal of described main control unit.Described communication unit is used to realize the mutual of described main control unit and computer.Described wireless energy control units is used for according to the control signal control wireless network card of described main control unit and connection or the disconnection between the computer, the input of described wireless energy control units is connected with described main control unit, the output of described wireless energy control units be connected be used for and the communication interface and wireless network card of computer interconnection between.
Compared with prior art, physical isolation card of the present invention not only supports cable network to isolate, and also possesses the wireless network control function, thereby can effectively realize the physical isolation of intranet and extranet, and it is simple in structure and the application deployment cost is low.
As the preferred embodiments of the present invention, described communication unit comprises and is used for MINIUSB interface that links to each other with the computer USB interface and the USB extended chip that links to each other with described MINIUSB interface, described USB extended chip expands at least two with USB interface, described USB extended chip expands at least two with USB interface, one of them changes serial port chip by described USB and links to each other with main control unit, another links to each other with the output of described wireless energy control units, and described power interface unit also is used to described USB extended chip power supply.Main control unit communicates by USB interface and host computer, and wireless network card also communicates by USB interface and computer, and is simple in structure, be easy to realize.By the USB extended chip USB interface of computer is expanded to two-way at least, wherein one the tunnel connects wireless network card, and another road connects main control unit, can reduce the volume of physical isolation card.In addition, use USB to change serial port chip, further reduced the size of product.
Preferably, described power interface unit comprises pci interface and voltage stabilizing chip, and described USB extended chip links to each other with pci interface by described voltage stabilizing chip.Pci interface is the computer general-purpose interface, from the computer-internal power taking, can guarantee that the power consumption of product is no more than the voltage that each pin provides on the PCI slot, the limit value of electric current, has guaranteed the safety of product electricity consumption, has also guaranteed the safety of computer itself.
Concrete, described hard disk switch unit comprises power supply transfer mouth and hard disk diverter switch, one road input of described power supply transfer mouth is connected with computer power supply, the two-way output links to each other with two hard disks by the output of described hard disk diverter switch, the input of described hard disk diverter switch links to each other with described main control unit, described hard disk switch unit has guaranteed to have only a hard disk energising, has guaranteed the safety of computer power supply.
Preferable, described main control unit comprises that reset signal is monitored subelement, current network state is obtained subelement and control sub unit.Described reset signal monitoring subelement is used for obtaining computer reset signal from described pci interface.Described current network state is obtained subelement and is used to obtain current place network.Described control sub unit is used to receive switching command, and after described reset signal monitoring subelement receives computer reset signal, obtain the described cable network switch unit of current place network control, hard disk switch unit and the wireless energy control units that subelement obtains according to described current network state.This main control unit has guaranteed to carry out change action after computer resets, thereby realizes protection hard disc of computer and the effect of self.
Further, described main control unit can also comprise the authentication subelement, is used to verify whether the user possesses the authority of handover operation, guarantees the safety of data.
Further, described main control unit can also comprise the switching command verification unit, described switching command check subelement is used for check and receives to such an extent that whether switching command is effective, thereby guaranteed not to be disturbed by the data that hash or other program are sent out, and prevented misoperation.
Preferably, described cable network switch unit, hard disk switch unit and wireless energy control units all adopt relay, its reliable in action, long service life.
Preferably, physical isolation card of the present invention can also comprise the hardware switch unit, and described hardware switch unit comprises key switch, and described key switch links to each other with described main control unit.Use described key switch, can under the state that computer is not started shooting, carry out network and switch.
Preferably, physical isolation card of the present invention can also comprise outernal display unit, is used for showing network state current or that switch next time according to the signal of described main control unit.When carrying out handover operation with key switch under the situation of not starting shooting, can show the network state of current or next switching at computer.
By following description also in conjunction with the accompanying drawings, it is more clear that the present invention will become, and these accompanying drawings are used to explain embodiments of the invention.
Description of drawings
Fig. 1 is the structured flowchart of an embodiment of physical isolation card of the present invention.
Fig. 2 is the structured flowchart of another embodiment of physical isolation card of the present invention.
Fig. 3 is the workflow diagram of physical isolation card of the present invention.
Embodiment
With reference now to accompanying drawing, describe embodiments of the invention, the similar elements label is represented similar elements in the accompanying drawing.As mentioned above, the invention provides a kind of physical isolation card, realize intranet and extranet isolation truly with wireless network isolation features.
Elaborate the technical scheme of the embodiment of the invention below in conjunction with accompanying drawing.As shown in Figure 1, the physical isolation card of present embodiment comprises main control unit 11, power interface unit 12, cable network switch unit 13, hard disk switch unit 14, communication unit 15 and wireless energy control units 16.Described main control unit 11 is used to receive external command and produces control signal according to the instruction that receives.Described power interface unit 12 is used to described main control unit 11 power supplies.Described cable network switch unit 13 is used for according to the signal of described main control unit 11 cable network being carried out the intranet and extranet switching.Described hard disk switch unit 14 is used for selecting and the corresponding hard disk of intranet and extranet according to the signal of described main control unit 11.Described communication unit 15 is used to realize the mutual of described main control unit 11 and computer.Described wireless energy control units 16 is used for according to the signal controlling wireless network card of described main control unit 11 and connection or the disconnection between the computer, the input of described wireless energy control units 16 is connected with described main control unit 11, the output of described wireless energy control units 16 be connected be used for and the communication interface and wireless network card of computer interconnection between, in the present embodiment, this communication interface is a USB interface.
Concrete, described main control unit 11 is minimum Single Chip Microcomputer (SCM) system, described power interface unit 12 can link to each other with the computer-internal power supply, also can link to each other with external power source.Described communication unit 15 can adopt serial communication or and port communications.Described hard disk switch unit 14 can adopt the mode that power supply switches, data are switched or both combine that hard disk is switched.
The physical isolation card of present embodiment not only has the cable network isolation features, also possesses the wireless network control function, thereby can effectively realize the physical isolation of intranet and extranet, and it is simple in structure, lower deployment cost is low.
Fig. 2 is the structural representation of another embodiment of physical isolation card of the present invention.As shown in Figure 2, the physical isolation card of present embodiment comprises that physical isolation card comprises main control unit 21, power interface unit 22, cable network switch unit 23, hard disk switch unit 24, communication unit 25 and wireless energy control units 26.Described power interface unit 22 is used to described main control unit 21 power supplies.Described cable network switch unit 23 is used for according to the signal of described main control unit 21 cable network being carried out the intranet and extranet switching.Described hard disk switch unit 24 is used for selecting and the corresponding hard disk of intranet and extranet according to the signal of described main control unit 21.Described communication unit 25 is used to realize the mutual of described main control unit 21 and computer.Described wireless energy control units 26 is used for according to the signal controlling wireless network card of described main control unit 21 and connection or the disconnection between the computer, the input of described wireless energy control units 26 is connected with described main control unit 21, the output of described wireless energy control units 26 be connected be used for and the communication interface and wireless network card of computer interconnection between.
Concrete, described main control unit 21 comprises that reset signal is monitored subelement 213, network state is obtained subelement 213 and control sub unit 211.In the present embodiment, described reset signal monitoring subelement 213 is used for obtaining computer reset signal from described pci interface 221, i.e. the high-low level of pci interface pin.Described current network state is obtained subelement 212 and is used to obtain current place network.Described control sub unit 211 is used to receive switching command, and after described reset signal monitoring subelement 213 detects computer reset signal, obtain the described cable network switch unit 23 of current place network control, hard disk switch unit 24 and the wireless energy control units 26 that subelement 212 obtains according to described current network state.Described main control unit 21 can be single-chip minimum system, comprises single-chip microcomputer and necessary crystal oscillator and electric capacity, and aforementioned subelement all is included in the described single-chip microcomputer.
Preferable, described main control unit 21 can also comprise and is used to verify whether the user possesses the authentication subelement of the authority of handover operation (figure does not show), further guarantees safety of data.Described main control unit 21 can also comprise switching command check subelement (figure does not show), and whether described switching command check subelement is used to check the switching command that receives effective.Thereby guaranteed not to be disturbed, prevented misoperation by the data that hash or other program are sent out.
Concrete, described communication unit 25 comprises and is used for changeing serial port chip 253 with computer USB interface (figure does not show) the MINIUSB interface 251 that links to each other, the USB extended chip 252 that links to each other with described MINIUSB interface 251 and USB, described USB extended chip 252 expands at least two USB interface with USB interface of computer, one of them links to each other with the control sub unit 211 of main control unit 21, another links to each other with the output 26 of described wireless energy control units, and described power interface unit 22 also is used to described USB extended chip 252 power supplies.Main control unit 21 communicates by USB interface and host computer, and wireless network card 29 also communicates by USB interface and computer, and is simple in structure, be easy to realize.And by the USB extended chip USB interface of computer is expanded to two-way at least, connect main control unit 21 and wireless network card then, make that the physical isolation card volume is little, cost is low and efficient.In addition, use USB to change serial port chip 253, further reduced the size of product, make the product compactness attractive in appearance.
Preferably, the physical isolation card of present embodiment adopts the computer-internal power supply, and is safe and reliable.Concrete, described power interface unit comprises pci interface 221 and voltage stabilizing chip 222, described pci interface 221 is plugged on the computer general-purpose PCI slot, its 3.3V pin is 21 power supplies of described main control unit, and described voltage stabilizing chip 222 links to each other with the 5V pin of PCI slot and is converted into behind the 3.3V voltage and powers for described USB extended chip 252.Pci interface 221 is the computer general-purpose interface, from the computer-internal power taking, can guarantee that the power consumption of product is no more than the voltage that each pin provides on the PCI slot, the limit value of electric current, has guaranteed the safety of product electricity consumption, has also guaranteed the safety of computer itself.
In the present embodiment, described hard disk switch unit 24 adopts power supply to switch, and it comprises power supply transfer mouth 242 and hard disk diverter switch 241.One road input of described power supply transfer mouth 242 adopts the general parallel port of 4 pins hard disk power line to be connected with computer power supply, obtain the computer-internal power supply, the two-way output adopts the general parallel port of 4 pins hard disk power line output and two hard disks by described hard disk diverter switch 241, be that hard disk 29a links to each other with hard disk 29b, the input of described hard disk diverter switch 241 links to each other with the control sub unit 211 of described main control unit 21.Described hard disk switch unit 241 has guaranteed to have only a hard disk energising, has guaranteed the safety of computer power supply.
Concrete, described network switch unit 23 includes spider lines diverter switch 231 and two Ethernet interfaces 232,232, and wherein Ethernet interface 232 is connected with outer net, and Ethernet interface 233 is by netting twine and computer network card connection.
Preferably, aforementioned cable network switch unit 23, hard disk switch unit 24 and wireless energy control units 26 all adopt relay control, its reliable in action, long service life.
Preferably, physical isolation card of the present invention can also comprise hardware switch unit 27, and described hardware switch unit 27 comprises key switch, and described key switch links to each other with the pin of the single-chip microcomputer of described main control unit 21, by the high-low level signal triggering.
Preferably, physical isolation card of the present invention can also comprise outernal display unit 28, is used to show network state current or that switch next time, and described display unit 28 is connected with described main control unit 21.Described outernal display unit can comprise blue red two light-emitting diodes, and their light on and off situation shows two kinds of network states of intranet and extranet.
The workflow of physical isolation card of the present invention is described below in conjunction with Fig. 2 and Fig. 3.
At first, after powering on, after promptly computer resetted, the firmware program in the single-chip microcomputer of main control unit 21 can initialization single-chip microcomputer register and pin setting, while initialization USB extended chip 252 and USB commentaries on classics serial port chip 253.Subsequently, network state is obtained the network state that subelement 212 obtains needs switching, and returns to host computer, can show on the computer display interface that current state is Intranet, outer net or wireless.
Whether described control sub unit 211 monitorings have received switching command.This instruction can be from host computer, also can be from the key switch of hardware switch unit 27.If receive the switching command of host computer from USB interface, then whether the switching command that receives by the check of described switching command check subelement is effective, and then whether the detection computations machine resets, if invalidly then data are emptied, waits for again receiving data.If key switch is pressed, then whether the detection computations machine resets.
Concrete, the step whether the detection computations machine resets is: the reset signal monitoring subelement 213 of described main control unit 21 obtains reset signal from pci interface 221.After getting access to computer reset signal, carry out handover operation.

Claims (10)

1. a physical isolation card comprises
Main control unit is used to receive external command and produces control signal according to the instruction that receives;
The power interface unit is used to described main control unit power supply;
The cable network switch unit is used for according to the control signal of described main control unit cable network being carried out intranet and extranet and switches;
The hard disk switch unit is used for selecting with intranet and extranet hard accordingly according to the control signal of described main control unit
Dish; And
Communication unit is used to realize instructing to receive external control alternately of described main control unit and computer;
It is characterized in that: also comprise wireless energy control units, be used for according to the control signal control wireless network card of described main control unit and connection or the disconnection between the computer, the input of described wireless energy control units is connected with described main control unit, the output of described wireless energy control units be connected be used for and the communication interface and wireless network card of computer interconnection between.
2. physical isolation card as claimed in claim 1, it is characterized in that: described communication unit comprises that being used for the MINIUSB interface that links to each other with the computer USB interface, the USB extended chip that links to each other with described MINIUSB interface and USB changes serial port chip, described USB extended chip expands at least two with USB interface, one of them changes serial port chip by described USB and links to each other with main control unit, another links to each other with the output of described wireless energy control units, and described power interface unit also is used to described USB extended chip power supply.
3. physical isolation card as claimed in claim 2 is characterized in that: described power interface unit comprises pci interface and voltage stabilizing chip, and described USB extended chip links to each other with pci interface by described voltage stabilizing chip.
4. physical isolation card as claimed in claim 3, it is characterized in that: described hard disk switch unit comprises power supply transfer mouth and hard disk diverter switch, one road input of described power supply transfer mouth is connected with computer power supply, the two-way output links to each other with two hard disks by the output of described hard disk diverter switch, and the input of described hard disk diverter switch links to each other with described main control unit.
5. physical isolation card as claimed in claim 4 is characterized in that: described main control unit comprises
Reset signal monitoring subelement is used for obtaining computer reset signal from described pci interface;
Network state is obtained subelement, is used to obtain current place network; And
Control sub unit, be used to receive switching command, and after described reset signal monitoring subelement receives computer reset signal, obtain the described cable network switch unit of current place network control, hard disk switch unit and the wireless energy control units that subelement obtains according to described current network state.
6. physical isolation card as claimed in claim 5 is characterized in that: described main control unit also comprises the authentication subelement, is used to verify whether the user possesses the authority of handover operation.
7. physical isolation card as claimed in claim 6 is characterized in that: described main control unit also comprises switching command check subelement, is used for check and receives to such an extent that whether switching command is effective.
8. all adopt relay as each described cable network switch unit of claim 1-7, hard disk switch unit and wireless energy control units.
9. physical isolation card as claimed in claim 8 is characterized in that: also comprise the hardware switch unit, described hardware switch unit comprises key switch, and described key switch links to each other with described main control unit.
10. physical isolation card as claimed in claim 9 is characterized in that: also comprise outernal display unit, be used for showing network state current or that switch next time according to the signal of described main control unit.
CN 201010124645 2010-03-03 2010-03-03 Physical isolation card Pending CN101800649A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102890619A (en) * 2011-07-18 2013-01-23 吴慧敏 Novel desk computer hard disk selector
CN109144830A (en) * 2018-09-06 2019-01-04 山西警察学院 A kind of acquisition of data fails to report supervision and is switched fast the method and system of network environment
CN109309674A (en) * 2018-09-19 2019-02-05 广州市图文科技有限公司 A kind of simple and safe practical dual net physical isolation automatic switchover technology

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2771917Y (en) * 2005-01-10 2006-04-12 北京太极英泰信息科技有限公司 Computer safety control module
US20060104200A1 (en) * 2004-11-18 2006-05-18 Samsung Electronics Co., Ltd. Terminal for automatically changing operating mode and wireless network system having the same, and method thereof
CN2790051Y (en) * 2005-04-18 2006-06-21 梁雁文 Network isolation device based on PCI bus

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060104200A1 (en) * 2004-11-18 2006-05-18 Samsung Electronics Co., Ltd. Terminal for automatically changing operating mode and wireless network system having the same, and method thereof
CN2771917Y (en) * 2005-01-10 2006-04-12 北京太极英泰信息科技有限公司 Computer safety control module
CN2790051Y (en) * 2005-04-18 2006-06-21 梁雁文 Network isolation device based on PCI bus

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102890619A (en) * 2011-07-18 2013-01-23 吴慧敏 Novel desk computer hard disk selector
CN109144830A (en) * 2018-09-06 2019-01-04 山西警察学院 A kind of acquisition of data fails to report supervision and is switched fast the method and system of network environment
CN109309674A (en) * 2018-09-19 2019-02-05 广州市图文科技有限公司 A kind of simple and safe practical dual net physical isolation automatic switchover technology

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Open date: 20100811