With the advent of Internet of Things (IoT), an increasing number of devices start exchanging information. This puts emphasis on wireless sensor networks (WSNs) to facilitate the interaction with the environment in varied application scenarios such as, for example, building and home automation among others. These generally require reliable, energy-efficient communication with low complexity. In this context, unidirectional communication, i.e., where nodes either send or receive data, seems to be an interesting solution. Since no elaborate feedback mechanisms such as carrier sensing, acknowledgments and retransmissions schemes are possible, complexity, costs, energy consumption and communication overhead are reduced in a considerable manner. On the other hand, however, packet loss becomes more likely making such networks strongly unreliable. To overcome this predicament, two MAC (Medium Access Control) protocols are proposed, namely DEEP and RARE. These consist in nodes transmitting their data as sequences of redundant packets with carefully selected inter-packet separations leading to robust transmission patterns that enable reliable communication. In this talk, the challenges of wireless communication will be discussed, the DEEP and RARE protocols will be presented and a comparison with other state-of-the-art protocols will be made.