This section provides the description of the main security and privacy components of the proposed framework. Unlike the current Internet, IoT interaction patterns are often based on short and volatile associations between entities without a previously established trust link. However, given the dynamic and distributed nature of IoT, it is necessary to consider more flexible data sharing models in which some information can be shared with a group of entities or a set of unknown receivers and, consequently, not addressable a priori. In addition, the way in which this information is disseminated must consider contextual data in which sharing transaction is going to be performed, due to the pervasive character of the envisioned IoT scenarios.