As alluded to in the introduction, under GPSR, packets are marked by their originator with their destinations’ locations. As a result, a forwarding node can make a locally optimal, greedy choice in choosing a packet’s next hop. Specifically, if a node knows its radio neighbor positions, the locally optimal choice of next hop is the neighbor geographically closest to the packet’s destination. Forwarding in this regime follows successively closer geographic hops, until the destination is reached. An example of greedy next hop choice appears in Figure 1. Here,x receives a packet destined for D. x’s radio range is denoted by the dotted circle about x,and the arc with radius equal to the distance between y and D is shown as the dashed arc a bout D. x forwards the packet toy, as the distance between y and D is less than that between D and any of x’s other neighbors. This greedy forwarding process repeats, until the packet reaches D.