Design And Impelmentation Of Network Hard Disk Based On NFS And SATA Protocol

Since the twentieth century, with the rapid development of science andtechonology and growth of information, people’s requesting of the convenienceand quickness of information storage was becoming increasing, the convenienceand quickness information storage rely on network is required. Against thisbackground, network hard disk technology was born and developed quickly. Atpresent, various types based on B/S mode network drives exists already, butthere are some limitations, which contains the client cannot operate files onlineand in real-time; client who want to read, write and modify the files mustdownload the files first; in addition, the existing network hard disks have otherproblems, for example, the limitation size of a single file, and a single video filewhich out of the limitation cannot be played.Aimming at the problems referred, this paper designed and implemented aC/S mode network hard disk based on NFS and SATA, it enables users to accessremote files as same as to access local files, and it has no limitation of the filesize, the system designed on the platform linux virtual machines and FGPA,using hardware and software co-design. The step of software part design is: first step, analyze the code of NFS client and server-side from Linux kernel andthe FAT32file system code; second step, design FAT32file system, NFSsystem,drivers with C language, then compile and verify them on virtualMachine. The hardware part SATA hard disk used VHDL hardware descriptionlanguage to design, it designed in ISE, and package it as a IP core based on PLBbus; at last, verification it on the development board XUPV5_LX110T. The laststep, integrated the software part to the operate system image, download thehardware bit stream and operate system to the development board, then verifiedit.To meet the modern society requirements of processing speed, the paperoptimized the designed system. Firstly, described the ACL mechanism, designACL as a appilication program, add it to the NFS server pplication programs list,then add multi-threaded design with thread pool technology, finally designedmulti-client applications with using of the technology multi-threaded and ACLmechanism, and describes solution to the conflict of multi-client access.Verification results show that this design can achieve the basic function ofnetwork hard disk to access remote files, and users can access online, with highsafety and reliability.