Maurer, FelixLabitzke, SebastianMüller, PaulNeumair, BernhardReiser, HelmutRodosek, Gabi Dreo2017-07-262017-07-262014978-3-88579-625-1Years ago, the World Wide Web (WWW) began as a system for publishing interlinked hypertext documents. While the protocols on top of which the WWW is built are almost still the same, the usage, as well as the content have changed significantly. Simple delivery of hypertext documents has been expanded by operations, such as uploading, sharing, and commenting on pieces of content. Online Social Networks (OSNs) and other IT services provide aggregated views on these pieces of content. However, the services are often implemented as vendor specific applications on top of common web technologies, such as HTTP, HTML, JavaScript and CSS. Moreover, users are locked into these applications of dedicated providers, which prevents sharing of content across applications and limits the control users have over their data. Most existing approaches that overcome these issues focus on defining a common HTTP API or prefer solutions based on peer-to-peer networks. In this paper, we start by discussing related work and identifying essential requirements for an appropriate solution. Furthermore, we outline the concept and implementation of a Federated Object Sharing Protocol (FOSP), i.e., a different approach to support today's common operations on social content already on a protocol level. We show that services built on top of this protocol can be federated by default, i.e., users registered with different providers can easily interact with each other. Finally, we provide an evaluation and discussion on the proposed approach.enText/Conference Paper1617-5468