Continuous Data Protection is a data recovery method which can protect file systems against malicious attacks or users’ mistakes. This paper proposes BCFBS (BUPT Continuous File Backup System): a continuous data protection architecture at file level. Compared with other approaches, it uses caching technique to protect the consistence between file versions, thereby speeding up both the backup of file version and space recycling. Furthermore, BCFBS combines techniques of filter the type of file, adjusting the frequency of the backup of file with incremental backup to make up the storage waste default of traditional CDP. Experimental results demonstrate that BCFBS can save storage space by 50%.

Cloud storage, which is composed of a large number storage devices and servers, provides large-scale flexible storage services through Internet. BCSS (Bupt-Cloud-Storage System) based on some cheap irresponsible PCs is designed as a mass storage platform to offer high reliable and available storage services. Meanwhile, it improves performance of data access by providing support of multi-user concurrent control. The experimental results verify efficiency of storage services and the performance of BCSS.