The system based on Voice Over IP (VOIP) technology is made up of SOS Call Boxes (set out along the roadway, preferably in the emergency platforms and tunnels) and Call Centre The SOS Call Box is made of a single column with a container boxed in stainless steel (see the pictures above); the container is made of a frontal panel which acts as an interface for the user and of an electronic control unit. The Call Box can be a cabinet in fibreglass or in stainless steel (installations along the roadways in the emergency platforms) otherwise it can be a cabinet in stainless steel with a space for extinguishers (installations in tunnels). The electronic control unit is fed by a 3Ah buffer battery loaded by solar panel or by network. The system is able to manage one or more tele-cameras/radar sensors to monitor the state of traffic