Design And Implementation Of A Cloud-Oriented File Sync Service System

Currently, with the development of socio-economy and IT industry, more and more individuals have multiple computing devices. Meanwhile, the number of individuals who own more than one such device like a desktop, laptop, smart phone and etc, will be continuously increasing owing to the new digital product launch. The utility of multiple devices brings users convenience in daily work and life, while it also challenges the personal data management. The issue of how to maintain the consistency of the personal data collections stored on multiple devices as well as other issues must be resolved for multiple devices users urgently.The cloud-oriented file sync service (FSS), which synchronizes the personal data collections stored on multiple devices automatically and supplies the cloud storage service through a cloud computing business model, is an efficacious solution for the above challenges. In this thesis, an autonomous FSS system named EaSync is designed and implemented based on the research and analysis of the current related products of FSS systems. And the main works are focused on the research and implementation of a consistency protocol toward the personal data collections and the related storage architecture which is appropriate for our FSS system. The main works accomplished in this thesis are as following:1) A new concept of user-view was proposed in this thesis to solve the core issue—how to maintain the consistency of personal data collections in FSS. The user-view is defined as a file abstraction layer toward multiple devices users, which represents all the files and their metadata in a collection and can simplify the design and implementation of the consistency protocol.2) Types of FSS system models were analyzed and summarized in this thesis, and a user-view based FSS system model was proposed without any technical details of the FSS products from their suppliers. Then our user-view based FSS system architecture was constructed according to the model.3) A user-view based consistency protocol was designed and implemented in this thesis, which efficaciously maintains the consistency of collections stored on multiple devices including the FSS storage center. And all the sync operations and conflict handling are automatically completed in the process of the interaction between the clients and server of our FSS system, and all the operations are transparent to users.4) This thesis also researched the storage technology for the FSS storage center according to the storage requirements in FSS, then proposed the storage architecture appropriate for our FSS system and optimized it.5) A prototype system also named EaSync was designed and implemented for the proposed FSS system architecture, and its feasibility and performance were evaluated in this thesis. The actual running of EaSync in the LAN environment has proved the validity of our works. Meanwhile, this thesis measured the time consumption of each synchronous operation on EaSync and compared it with iFolder, which is an open source implementation of a FSS system. The results show that EaSync outperforms iFolder and has a high practical value.