The Research On Key Technologies In Cloud Torage System

Nowadays, characterized by providing services and paying as you go, cloud computing hasreceived a lot of attention from many enterprises and researchers. It has also become one of themost popular terms in emerging technology and service fields. Meanwhile, cloud storage, whichis an extension of the conception and practice of cloud computing, is coming into people’s sights inthe form of the applications that provide services on demand like personal Dropbox、iCloud、GoogleDrive and public cloud storage like Amazon S3and Ali. Howerver, how to optimize the datareplication technology so as to improve the serviceability and reliability of cloud storage systemsremains the crucial problem that need to be resolved.The paper is focused on the data replication technology in cloud storage systems. Firstly, analgorithm of data replica placement is proposed. We build corresponding replica placement model,dynamically adjust the quantity of replicas basing on the data visits and select the optimalplacement node considering synthetically the network topology, the system bandwidth, node loadand many other aspects of factors. And the consumption of network resources is reduced and useraccess latency is shortened. Secondly, an algorithm of consistency preservation of data replica isproposed. We calculate the read and write prevalence rate of data according to historial reading andwriting frequency and further define four data types: read-intensive, write-intensive, read-writesparse and read-write intensive. And eventually be selective about using different consistencypreservation algorithms according to data types. When the reading and writing frequency of datachanges, its consistency preservation algorithm can be adjusted, so we can effectively ensure eachreplica consistency on the condition that not increasing the maintenance cost of the system.Finally, a simple cloud storage system is implemented basing on the Eucalyptus cloudcomputing platform. And the proposed data replica placement and consistency strategy was carriedout in this platform. Related simulations demonstrated that the key technology of data replication isfeasible in practical applications.