How do the nodes send data to the cloud?
The nodes send the data up through a network called the Helium network. The network is designed specifically for sensors like NOWis. You can learn more about the network at helium.com
How far from a hotspot can a node be?
The nodes should be conservatively within 0.3 miles of a hotspot, preferably 2 hotspots for redundancy. Installations that get the nodes antenna outside can extend farther.