Quality of experience in dense CSMA networks

Dense carrier sensing wireless networks are important scenarios to enable ubiquitous mobile Internet access. In this work, we study user experience from the end-to-end performance of dense p-persistent CSMA networks that suffers from operation interference among many non-coordinated APs. Results show that in dense networks, the effective coverage of APs shrinks and most STAs don´t receive satisfactory services which renders the network useless. We find that a dense network with multiple non-cooperative APs does not always result in lower latency. The RTS/CTS handshake also does not guarantee better latency than the basic access method in dense networks. For end-to-end throughput and end-to-end drop rate, results show that a dense network with many non-coordinated STAs has poor performance compared to that with few due to high collision, contention, and outage. On the other hand, a dense network covered by multiple APs offers better end-to-end performance compared to one covered by few. The RTS/CTS handshake also brings similar performance enhancement. Appropriate optimization associated with application scenarios are useful.