I. Introduction
In the last years, thanks to the recent technological advances in low power integrated circuits and wireless communications carried out by academic and industrial sectors, research fields have evolved in many directions at the same time. For instance, back in the middle of the last decade, Wireless Sensor Networks (WSNs) was one of the most promising fields in wireless communications [1] and a lot of research efforts were put mainly into three categories. First, the creation of low-power, low-cost communication protocols such as Zigbee, 6LowPAN or WirelessHart, among others. The second is the improvement of physical devices when a huge amount of different companies emerged offering their own designs. And, last but not least, new software approaches were studied and developed in order to create frameworks and middleware with the aim of dealing with unreliable links and changing topologies, but also by making embedded devices smarter and providing more secure communications, all this trying to make the programmers life easier as the development of software for embedded devices is sometimes complex [2] [3].