Developing the Cloud-integrated data replication framework in decentralized online social networks

• This work conducts the quantitative analysis about the storage capacity of a hybrid system combining DOSN and the Cloud.
• This work analyzes and predicts the probabilistic behavior of the friend circle in the DOSN.
• This work develops a data partition scheme in terms of replication techniques.
• This work develops the placement strategy for data replicas to realize the predicted data availability.

Decentralized Online Social Network (DOSN) services have been proposed to protect data privacy. In DOSN, the data published by a user and their replicas are only stored in the friend circle of the user. Although full replication can improve Data Availability (DA), pure DOSNs may not deliver sustainable DA. This paper proposes a Cloud-assisted data replication and storage scheme, called Cadros, to improve the DA in DOSN. This paper conducts quantitative analysis about the storage capacity of Cadros, and further models and predicts the level of DA that Cadros can achieve. The data in Cadros are partitioned in such a way that the overhead caused by storing the data in the Cloud is minimized while satisfying the desired DA. This paper also proposes the data placement strategies to realize the desired DA and improve other performance. Experiments have been conducted to verify the effectiveness of Cadros.