中文摘要：

对于广域网下的文件传输和管理,云存储系统提供Web Service API、基于文件的API、基于Block的API和其他的API,通常需要在客户端安装特定程序调用这些API实现云存储功能,测试发现如果多人同时访问,传输文件失败率较高。设计了基于Web Service、HTTP和Flash技术的文件传输协议VCFTP,开发了基于虚拟主机集群的云存储系统VCloudStorage。首先建立SaaS服务模型,利用HTTP数据流存储技术,建立虚拟主机存储接口;接着建立虚拟主机传输能力、存储能力和价格能力数学模型,结合用户的传输请求建立文件传输整数规划数学模型及最优化算法,最终以此为基础设计了文件传输控制协议VCFTP。VCFTP利用Flash跨平台和富客户端技术特点,无需在客户端部署其他程序;授权的用户根据传输请求、存储要求、服务水平和当前虚拟主机状态等条件,以传输能力最优化的方式进行文件传输。实验结果表明VCFTP具有较高的性能和稳定性,VCloudStorage总吞吐量、平均传输率和文件传输成功率均优于微软SkyDrive存储、腾讯QQ邮箱存储和单虚拟主机存储。本文提出的VCFTP增强了文件传输性能和稳定性,是提高广域网网络存储系统性能的一条有效途径。

英文摘要：

Cloud storage systems provide Web Service API,file-based API,block-based API and other API to transfer and manage file over the WAN.But it＇s necessary to install client programs to call the API.It was found that if many people transferred files at the same time,failure rate was higher in the experiments.This paper designed the file transfer protocol VCFTP based on Web Service,HTTP and Flash technology,and realized VCloudStorage,a cloud storage system based on virtual host.First of all,SaaS service model was established,and virtual host storage interfaces were created by the HTTP data stream storage technology.And it established the model of virtual host transmission,storage and price capacity,then created integer programming model and presented optimization algorithm based the virtual host transmission model and users transmission requests.Finally,transmission control protocol VCFTP was created.Using Flash＇s cross-platform and rich client technology features,VCFTP could transfer and manager files without installing other programs in the client.Authorized users could transfer files by optimization transmission capacity way in accordance with the transmission request,the storage requirements,service levels and the virtual host current state,etc.The experimental results showed that the VCFTP have high performance and stability,and total throughput,average transmission rate and file transmission success rate of VCloudStorage is superior to Microsoft＇s SkyDrive storage,Tencent QQ mailbox store and a single virtual host storage.The VCFTP protocol enhances file transmission performance and stability,and is an effective way that improves the performance of storage system in WAN.