Content sharing in cloud storage leads to multiple downloads of the same content when users synchronize devices. These downloads contribute to bandwidth waste and increase server workloads. Here, the authors investigate traffic generated by Dropbox and use data collected from four networks to show that a large fraction (57-70 percent) of downloads generated by Dropbox users is associated with content shared among multiple devices. They present an alternative synchronization architecture that

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... s caches to offload storage servers from such downloads. Their experiments show that the approach costeffectively avoids most repetitive downloads, benefiting service providers, the network, and end users.