While low power communication has evolved towards multi-kilometer ranges and low bit-rate schemes in recent years, triggering increasing interests, a trade-off must still be made between power consumption and latency. Using pure-asynchronous communication allowed by emerging Ultra-Low-Power (ULP) wake-up receivers (WUR), WakeUp aims at proposing a low latency and energy efficient network architecture composed of heterogeneous radio nodes (long-range communication and ULP short-range WUR) with dedicated access and network protocols. This project is the fruit of joint reflexions of French research groups on Systems-on-chips (GDR Soc-Sip) and on Networking (GDR RSD) that made indeed emerged the wake-up radio as the technology that will surely change network paradigm for the next decade. A two-way cross layer optimization is envisaged in WakeUp, since on the one hand these heterogeneous network higher layers will take into account the specificities of the wake-up radio to optimize energy and latency, and on the other hand some recurrent application constraints will lead to specific wake-up radio designs. Our balanced consortium is composed of two academic partners (University of Rennes and University of Strasbourg), one state-owned industrial and commercial establishment (CEA LETI) and one SME (Wi6Labs). The consortium will address these scientific challenges at both the node and the network level, with controlled (FIT IoT Lab) and real-field experimental validations.