The Research Of Embedded Linux System Network Access Security Based On ARM

Information, intelligence and network hans become today’s society identifier, andthe embedded technology is becoming more and more stable. Embedded systems arewidely applied in all ereas of life, such as: intelligent appliance, automobile electronicsand3G application. Because of its good stability, high reliability, and it is of greattheoretical and practieal significance to study the prineiple of Linux operating system, toport the embedded Linux system and to develop the application programs.The research of this paper is based on the ARM Microprocessor Design andImplementation of Ethernet circuits. Firstly, this paper constructs to achieve the smallestARM systems in peripheral circuits, including SDRAM and FLASH chip access. Then itbuilds a Linux system allows to operate through the target host, through theestablishment of cross-compiler, depending on the target machine U-Boot transplant,transplanting kernel and root file system construction to achieve the Linux operating.And the data transfer between protocol layers is achieved by using the Linux protocolstack, including ARP protocol, ICMP protocol, IP protocol, TCP protocol, UDP protocolas well as the communication mechanism SOCKET. Finally the paper describes how thedata packets transmitted in the network as well as secure gateway to the rationalallocation of traffic, where the data is encrypted using VPN technology in IPSsec andwhere rational distribution of the flow is mainly through the LAN client applicationsoftware to monitor.