We show that the per node overhead of traffic control in a mobile ad hoc network with N nodes with density ν moving at average speed ν can be made proportional to √νNν). In this case route between source and destination has a bounded strectch factor compared to optimal route. Since by Gupta and Kumar scaling property the per node traffic cannot be larger than some O(1/log N). Therefore there is a maximal network size which depends of speed ν and node density. We show that we moderate hypotheses (location aware nodes) this size can be significantly large.