This work provides an analysis of topological uncertainty in wireless networks. Here, we model a wireless network as a random geometric graph (RGG) and quantify topological uncertainty in terms of the Shannon entropy of the underlying graph model. Direct pairwise connections between nodes are probabilistic in general, and thus our analysis covers cases where channel randomness contributes to uncertainty in the network topology. We derive a simple bound on RGG entropy. We then consider a pairwise connection model based on small-scale Rayleigh fading and study the behavior of the entropy bound as the number of nodes n in the network grows large while the typical connection range r0 increases or decreases. We present three key results that qua...