Technological development in terms of power requirement for data acquisition and processing opens new perspectives in the field of environmental monitoring. In particular, near real-time data flow about the sea condition, and a possible direct interface with applications and services devoted to marine weather networks would have a significant impact on several aspects such as, for example, safety and efficiency. In this scenario, the paper analyses the needs of buoy networks and focuses on the estimation of directional wave spectra from buoys data. Both simulated and real experimental data are considered for demonstrating the effectiveness and the potentialities of the considered estimation methods.