Take Back your Friends with DCS: A Decentralized Connectivity Service for Private Social Communication Apps

Abstract

Our friends and whom we associate with in our personal and working lives is a fundamental part of our identity. On the Internet, this part of our identity is in the hands of others. People rely on a variety of VoIP/chat/instant messaging and other applications to socialize, inform and collaborate with others. To use these centralized services, users must either hand over their full list of associations or have their associations tracked over time by the centralized service. This results in lack of user privacy, lock-in of users who cannot easily switch to another service, and a general stifling of application innovation. In this paper, we propose decoupling such applications from the list of associations. We present the Decentralized Connectivity Service (DCS), a privacy-preserving blockchain-based connectivity service for distributed social communication applications. DCS puts control of a user's interactions with others, back in the hands of the user and allows users to establish point-to-point connections with other users, without the use of a centralized party. DCS consists of a set of DHT nodes and a local Contact Management Service that resides on the user's local device that, together, facilitate social communication applications running on edge devices to establish connectivity. A user's associations (i.e., contacts/friends-list) never leave the user's personal device without user permission and thus, remain under the user's control. We present the design of DCS and show how we leverage the use of a smart contract to provide monetary incentives for users to participate in the system.