(as the price of individual lamps is still higher than that of traditional ones, although it is rapidly becoming cheaper and cheaper) but by energetic or environmental considerations. These lamps combine very low power consumption with an extremely long operational life, maintaining during all their operation the same chromaticity without significant changes. LED lamps can be also used as communications emitters without losing their main functionality as illumination sources. This technique (known as Visible Light Communications or VLC) does not only maintain the usual capabilities of wireless optical transceivers (robustness against EM interference, absence of EM compatibility constraints and secure transmissions as radiation is confined by walls) but is also eye-safe (as it uses visible wavelengths). Additionally, as they are used as lamps, the amount of optical emitted power is enough to provide full transmission coverage over a regular size room. So we have a huge amount of low cost COTS (commercial off-the-shelf) optical emitters available that can be used wherever we need to provide illumination and to broadcast data jointly.