The Research And Design Of NICs Redundant And Hot-Standby Hardware Independent On Windows

The demand for information technology in today's society becomes more and more popular, more and more urgent, followed by the network security, reliability and real-time requirements have become more higher. The redundancy hot-standby of network system enhances the reliability of network's transmission. One of the cores that achieve network hot-standby is that achieves the redundancy hot-standby of double network card, that is only primary network card made used of communication. The redundancy hot-standby system of double network card detects primary network card and link real-timely, and then , switches the standby card to primary card to work automatically. Hot-standby switching is nothing with superstratum application, and couldn't affect network communication of application in the process of switching.The paper adopts the communication interface standard NDIS which between Windows and network card driver to realize redundancy hot-standby of double network card without concreting network card hardware. The main contents are as follow:(1) The paper firstly analyzes and compares Windows network architecture, OSI model and TCP/IP protocol, deeply analyzes the realization mechanisms of network communication.(2) Analyzing basic function demand of the redundancy hot-standby system of two NICs, The key processes of the hot-standby switching included mainly: two NICs share one IP address before and after switch, detecting the failure of NIC and link real-timely and hot-standby switching automatically, realizing the bond of double network card, physical address couldn't change in the process of switching. After analyzing, the paper chooses the solution that is capturing and modifying Windows packet to make two NICs share one IP address, which achieves network card switching. Comparing the advantages and disadvantages of network programming in Windows user mode and kernel mode, the paper uses intermedia driver to design the system. The paper analyzes architecture, frame and the data packets operation of intermedia driver.(3) The innovative measure is to use intermediate driver's position to capture and modify data packets received and sended, and realize two network card bound sharing one IP address. Using intermediate driver to bind double network card, and controlling primary and standby relation bound. Using miniport driver to maintain the information of network card, and realizing failure detecting real-timely. Simultaneity using LBFO mechanism provided, the paper realizes switching automatically. After the switching of network card, using the function that query and set the NIC information of miniport driver, the physical address of the new primary network card is seted the value of the original primary network card physical address to reduce the time of rebuild communication line. (4) Using system reliability theory, and analyzing the reliability and security guideline of the redundancy hot-standby network system.