摘要 : The unpredictable growth of data in the current digital world requires more data storage space, which reduces the performance and improves the cost for the backup tremendously. The data generated from real time sensor applications... 展开 The unpredictable growth of data in the current digital world requires more data storage space, which reduces the performance and improves the cost for the backup tremendously. The data generated from real time sensor applications have more duplicates than other applications. Data storagewith duplicate copies increases access time and processing cost. The de duplication process removes the duplicate data has been used for long time archival and backup storage. Several methods are proposed to purge replica at the file level, at the chunk level. This paper reviewed the existingde duplication methods DARE and LBP based de-duplication. The performances of the methods are analyzed to measure the efficiency of the de-duplication and also present some of the key issues need to be focused in the future. 收起