Cost-Benefit Tradeoffs of Content Sharing in Personal Cloud Storage

Personal Cloud Storage (PCS) is a very popular Internet service. It allows users to backup data to the cloud as well as to perform collaborative work while sharing content. Notably, content sharing is a key feature for PCS users. It however comes with extra costs for service providers, as shared files must be synchronized to multiple user devices, generating more downloads from cloud servers. Despite the increasing interest in this type of service, a thorough investigation on the costs and benefits of PCS for service providers and end users has not been conducted yet. To that end, we propose a model to analyze cost-benefit tradeoffs for both parties. We develop utility functions that capture, in an abstract level, the satisfaction of the service provider and users in various scenarios. Then, we apply our model to evaluate alternative policies for content sharing in PCS. We consider two alternative policies for the current PCS sharing architecture, which count on user collaboration to reduce providers' costs. Our results show that such policies are advantageous for providers and users, leading to 39% utility improvements for both parties, while requiring low commitment of resources from participating users.