Quickly looked over this and the thing that caught my eye is that it says you can set up distributed systems that are available offline through device to device

Quickly looked over this and the thing that caught my eye is that it says you can set up distributed systems that are available offline through device to device communication. At least, I think that is what it does. I could not quickly find more information on that. A diagram or something would be helpful to visualize this, with an explanation of the protocols that are used. Maybe I missed the examples or case study section.