Effect of TCP Variants on the Performance of 802.11 Networks for IoT

The Internet of Things (IoT) platforms provide connectivity between sensor devices communicating over various wireless links. Main objective of IoT is to deploy smart cloud data services that generate real time response to mass amount of sensor data collected over these connections. Therefore, IoT systems have Quality of Service (QoS) requirements that need to be satisfied by the underlying networks. In IoT network stacks, end-to-end reliability is provided by application level protocols which use TCP connections at the transport layer. On the other hand, a disadvantage of the TCP is the poor performance of its congestion control policy over wireless links. To alleviate this problem, several TCP variants have been proposed and implemented in networks with wireless links. In this study, we study the performance of three TCP variants; new Reno, CUBIC and Thaoe for various 802.11 protocols used in WLAN settings. We conducted comprehensive simulations in a setup that typically represents a remote monitoring use-case scenario in an IoT application. The results reveal that the TCP variant used in the protocol stack may have a critical role in the overall performance.