Data transmission by any means
The signal is transmitted by various means of data transmission, both by fiber-optic and copper-electric cables, and by means of electromagnetic waves (radio band). It can be used for remote territories without built technical infrastructure, (for example, groups of islands are controlled via satellite).
This is necessary in case of emergencies, since in most cases a failure in the supply of electricity entails the failure of the entire telecommunications infrastructure. That is why large warning systems use two independent channels to control the siren network.
Such systems are used in situations of real danger, so we need full confidence that they will really work when it is necessary. Therefore, great demands are placed on the functions of self-diagnosis of sirens and on the infrastructure that relates to them. A possible error is detected even before using the siren and corrected in a timely manner.
The activation speed is measured in tens of seconds: 350 sirens are activated in about 20 seconds.
The speed of receiving feedback on the activation of sirens is measured in minutes: from 350 sirens (approximately 60 seconds).