LibreSocial: A Peer-to-Peer Framework for Online Social Networks

Abstract

Distributed online social networks (DOSNs) were first proposed to solve the problem of privacy, security and scalability. A significant amount of research was undertaken to offer viable DOSN solutions that were capable of competing with the existing centralized OSN applications such as Facebook, LinkedIn and Instagram. This research led to the emergence of the use of peer-topeer (P2P) networks as a possible solution, upon which several OSNs such as LifeSocial.KOM, Safebook, PeerSoN among others were based. In this paper, we define the basic requirements for an P2P OSN. We then revisit one of the first P2P-based OSNs, LifeSocial.KOM, that is now called LibreSocial, which evolved in the past years to address the challenges of running a completely decentralized social network. Over the course of time, several essential new technologies have been incorporated within LibreSocial for better functionalities. In this paper we describe the architecture and each individual component of LibreSocial and point out how LibreSocial meets the basic requirements for a fully functional distributed OSN.

Bridging separate communities with common interest in distributed social networks through the use of social objects

“…Finally, centralized OSNs can suffer from other problems such as limited scalability and high maintenance costs to manage the data of so many users. In DOSNs, shifting to the user both the implementation of the infrastructure and the privacy and security control effectively reduces the operational cost [29], [30].…”

Content Privacy Enforcement Models in Decentralized Online Social Networks: State of Play, Solutions, Limitations, and Future Directions

“…As concern the scope, DOSNs enable users to create groups in order to either organize their own contacts in a private address book (such as, Safebook [7] or Vis-a-Vis [8]) or to create a community for connecting users among them (such as, groups in LifeSocial.KOM [10], ProofBook [40], or LibreSocial [41]). In the first case, groups are privately defined by the group creator based on the relationship he/she has with the group members (such as, family members, classmates, or colleagues), and the members are not aware of the groups they belong to, they cannot see the other members of the group, and they cannot decide to join/leave them or to publish a content in the group, because these groups are for the exclusive use of the group creator.…”

“…The join operation involves at least the group owner and the users who are being added to the group. It can be either initiated by the group owner or requested by a user who does not yet belong to the [9] community LibreSocial [41] community…”

“…For what concerns the group leave operation, most of the existing DOSNs allow the users removed from a group to still access the contents published prior to the execution of the leave operation (leave without backward secrecy). In a few number of DOSNs (such as PeerSoN [9] and LibreSocial [41]), instead, the group leave operation revokes the access rights to these contents to the removed members (leave with backward secrecy). In this case, although after the execution of the leave operation the DOSN prevents the removed members from accessing such contents anymore, this cannot be really considered as an effective countermeasure for protecting the privacy of such contents.…”

“…Without loss of generality, we can assume that the selected privacy enforcement models allow users to protect the contents they publish by defining the group of users who can access these contents. As a matter of fact, Section 2 shows that a very common solution to express privacy preferences in DOSNs LKH+TGDH [31] Vis-a-Vis [8] LifeSocial.KOM [10] DOSN LKH [28,32] My3 [34] DECENT [43] LKH+OFT [30] DiDuSoNet [36] SocialGate [12] Shi R.H. et al [44] Privacy Policy [38,39] LotusNet [13] ELK [45] Trust [35] Contrail [42] OFT [33] Zeng S. et al [46] ProofBook [40] LKH [29] eXO [47] Safebook [7] DGKD [48] Solid [49] SuperNova [14] Bortoli S. et al [50] LibreSocial [41] BCOSN [51] WebP2P [52] Megaphone [53] SEDOSN [54] ReClaim [55] PSON [56] (and OSNs) is the definition of groups of users. An alternative solution to specify the users who can access a content is the one that expresses privacy preferences through attribute based access control policies.…”