The Research And Realization Of Net Gap System Based On Memory Exchange

With the development of network technology, network applications become more and more important in many crucial fields. But there emerge many network attacks when we communicate with network, and the attacks damage the information system seriously, so network security technology has become the important research topic for many governments and organizations. As a high-level security equipment, Net Gap makes up the shortage of the other products, and implements the Gap Technology. The Net Gap' s function is to cut the protocol of the net communication and to isolate trustworthy inner net and unauthentic outer net in physics and to complete the data exchange between nets under the precondition that ensuring the intranet in safe.The Net Gap Based on Memory Exchange is the subproject of "industrialization of the godson CPU" . This paper' s content is the design and research of the project. The Net Gap had past the test and been adopted by the Beijing BHL Networks Technology Co., Ltd. After loading the Godson CPU, there will be a network security system with complete IP.At first, the paper expatiates the background of the project, analyses the security problem in network and the correlative recovery technology. Then the paper introduces impolder process of the PCI interface and the ATA interface, analyses the simulate wave in Modelsim. As the emphasis of the project, the process of the Net Gap card is introduced amply, which includes the system architecture and the layout. At last, the paper discusses a new architecture design of Net Gap.