Next to traditional communication systems like servers or routers at the backbone and personal computers or laptops acting as clients, the Future Internet will additionally comprise many so-called smart objects. Most of everyday devices like coffee machines, fridges, or light switches will participate in this Internet of Things (IoT).Small-sized computers will connect these devices to the network by establishing low power wireless links. To achieve this vision various kinds of wireless multi-hop networks (WMHNs) play an important role. During the last years, it has become clear that test bed-based research is mandatory in order to develop suitable protocol implementations and metrics for these networks. In this article, we review network configurations for wireless networks for the IoT. We describe the DES-Test bed at the Freie UniversitÃ¤t Berlin as an experimental facility to study these network configurations. In addition to the infrastructure and software provided by the test bed, we introduce Âµkleos as a micro kernel based operating system for embedded devices. We designed Âµkleos with a special focus on Wireless Sensor Networks (WSNs) to complement our approach to study WMHNs.Âµkleos provides an implementation of 6LoWPAN to interconnect WSNs to IP-based networks.