Biblio

The heart of the Internet of Things (IoT) is data. IoT services processes data from sensors that interface their physical surroundings, and from other software such as Internet weather databases. They produce data to control physical environments via actuators, and offer data to other services. More recently, service-centric designs for managing the IoT have been proposed. Data-centric or name-based communication architectures complement these developments very well. Especially for edge-based or site-local installations, data-centric Internet architectures can be implemented already today, as they do not require any changes at the core. We present the Virtual State Layer (VSL), a site-local data-centric architecture for the IoT. Special features of our solution are full separation of logic and data in IoT services, offering the data-centric VSL interface directly to developers, which significantly reduces the overall system complexity, explicit data modeling, a semantically-rich data item lookup, stream connections between services, and security-by-design. We evaluate our solution regarding usability, performance, scalability, resilience, energy efficiency, and security.

Wireless Sensor Networks (WSN) are widely used to monitor and control physical environments. An efficient energy management system is needed to be able to deploy these networks in lossy environments while maintaining reliable communication. The IPv6 Routing Protocol for Low-Power and Lossy networks is a routing protocol designed to properly manage energy without compromising reliability. This protocol has currently been implemented in Contiki OS, TinyOS, and OMNeT++ Castalia. But these applications also simulate all operation mechanics of a specified hardware model instead of just simulating the protocol only, thus adding unnecessary overhead and slowing down simulations on RPL. In light of this, we have implemented a working ns-3 implementation of RPL with support for multiple RPL instances with the use of a global repair mechanism. The behavior and output of our simulator was compared to Cooja for verification, and the results are similar with a minor difference in rank computation.