5. Geographical routing

The idea behind geographic routing protocols is to use geographic information to route packets. To simplify the presentation, we'll assume that all nodes know their position, and that these nodes also know the position of all other nodes in the network. With these assumptions, it's easy to imagine that a node can easily choose from among its neighbors a relay to route a packet whose final destination it knows, and therefore also its position. It's very simple to envisage selection criteria among these neighbors; let's give a few examples from among the most classic heuristics.