With timers ? because undersea communication is not as solved problem AFAIK
The communication does not have to be fast, so they could use extremely low frequency signals, which apparently can travel over hundreds to thousands of miles in seawater. On top of that, they could build a mesh network.
alt Hacker News
The communication does not have to be fast, so they could use extremely low frequency signals, which apparently can travel over hundreds to thousands of miles in seawater. On top of that, they could build a mesh network.