支援行動內容分享的Upload-on-Demand方法

Abstract

As communication technologies and mobile devices keep improving, mobile content sharing has become one of the most popular mobile applications. The client-server content sharing service architecture can be divided into traditional client-server architecture and proxy-assisted client-server architecture. In the traditional client-server architecture, we need to upload the shared content to the server. In the proxy-assisted client-server architecture, we can utilize the proxy to transfer or receive the shared content. It shows that both of them should upload the whole content to the server. It also reveals that when the uploaded content is not downloaded by other users, this will result in the waste of the network bandwidth. Therefore, how to effectively utilize the network bandwidth when the wireless/ mobile bandwidth is limited will be an important task for providing the mobile content sharing service. The best way to save bandwidth is to avoid uploading unnecessary content. That is, upload the content only when it is requested. Hence, we adopt the concept of Upload-on-Demand (UoD) to create and develop a UoD content sharing method. In the UoD system, the user merely uploads the metadata and the preview of shared content, instead of uploading the whole content. We upload the whole content on the storage of UoD system only when other users request the download of such content. In this way, we can utilize effectively the bandwidth and provide a better content sharing service. In order to analyze the performance of the UoD system, we build a practical network test environment. At first, we study the impact of UoD strategy on the demand of network bandwidth. Secondly, we examine the influence of update frequency on download delay problems. Furthermore, we suggest a new strategy for UoD information update by deciding the best update frequency to satisfy the users' request of download delay and to save the bandwidth.