The routing protocol for low power and lossy networks (RPL) was recently designed in the IETF. We provide a new evaluation of this protocol with two approaches using two different simulators adapted to our needs. We first introduced mobile sinks to extend the wireless sensor network lifetime and analyzed the performances using the WSNet simulator, augmented by our own RPL module. We then focus on the performance comparison of simulated sensor networks and real power-line communication networks (PLC) using the RPL capable COOJA simulator, augmented by our own PLC module. Our studies give two new RPL evaluations and show the interest of choosing a simulation tool adapted to the simulation aim. As a conclusion, we demonstrated how these two case studies can be combined in a heterogeneous network architecture that extends the sensor network global lifetime.