Understanding link-level 802.11 behavior: replacing convention with measurement

Since wireless signals propagate through the ether, they are significantly affected by attenuation, fading, and interference. As a result, it is often difficult to measure and understand fundamental wireless network behavior. This creates a challenge for both network researchers, who often rely on simulators to evaluate their work, and network managers, who need to deploy and optimize operational networks. Given the complexity of wireless networks, both communities often rely on simplifying rules, which often have not been validated using today's wireless radios. In this paper, we undertake a detailed analysis of 802.11 link-level behavior using real hardware and a physical layer wireless network emulator that gives us complete control over signal propagation. We replace conventional assumptions and possible misconceptions with actual recorded behavior. Additionally, we analyze the impact of our observations on commonly deployed networks. Our work contributes to a more accurate understanding of link-level behavior and enables the development of more accurate wireless network simulators.