This paper analyzes the capacity of ad hoc wireless networks, focusing on the impact of network size, traffic patterns, and local radio interactions. It uses simulations and first-principles analysis to determine the achievable capacity and its scaling behavior. The study shows that the capacity of ad hoc networks is significantly lower than expected due to the need for nodes to forward packets, leading to contention and reduced throughput. The paper examines the interaction between 802.11 MAC protocols and ad hoc forwarding, and how this affects network capacity. It also explores different traffic patterns, showing that local traffic patterns allow for more scalable capacity, while non-local patterns result in a rapid decrease in per-node capacity. The paper concludes that the feasibility of large ad hoc networks depends on the locality of communication. It also discusses the limitations of 802.11 MAC in handling ad hoc forwarding, showing that it achieves lower throughput than theoretically possible. The study highlights the importance of understanding network capacity when evaluating ad hoc networks and provides insights into the scalability of these networks under different conditions. The paper also compares the performance of different traffic patterns, showing that random traffic patterns result in lower capacity than local or structured traffic patterns. The analysis concludes that the capacity of ad hoc networks scales with network size, but the rate of scaling depends on the traffic pattern and the underlying MAC protocol. The study provides a foundation for understanding the limitations and potential of ad hoc wireless networks.This paper analyzes the capacity of ad hoc wireless networks, focusing on the impact of network size, traffic patterns, and local radio interactions. It uses simulations and first-principles analysis to determine the achievable capacity and its scaling behavior. The study shows that the capacity of ad hoc networks is significantly lower than expected due to the need for nodes to forward packets, leading to contention and reduced throughput. The paper examines the interaction between 802.11 MAC protocols and ad hoc forwarding, and how this affects network capacity. It also explores different traffic patterns, showing that local traffic patterns allow for more scalable capacity, while non-local patterns result in a rapid decrease in per-node capacity. The paper concludes that the feasibility of large ad hoc networks depends on the locality of communication. It also discusses the limitations of 802.11 MAC in handling ad hoc forwarding, showing that it achieves lower throughput than theoretically possible. The study highlights the importance of understanding network capacity when evaluating ad hoc networks and provides insights into the scalability of these networks under different conditions. The paper also compares the performance of different traffic patterns, showing that random traffic patterns result in lower capacity than local or structured traffic patterns. The analysis concludes that the capacity of ad hoc networks scales with network size, but the rate of scaling depends on the traffic pattern and the underlying MAC protocol. The study provides a foundation for understanding the limitations and potential of ad hoc wireless networks.