Performance analysis of a short flow favoring TCP

Most flows in the Internet run over TCP and most flows in the Internet are short. These TCP flows are predominantly disadvantaged in networks due to their short time to react to the environment along the flow path. There are arguments proposing TCP to favor short flows to counter such imbalance. It would improve user experience, reduce energy consumption of wireless devices and bring economic benefits to service providers. We describe sender-side-only TCP modifications to favor short flows and validate it through a Linux implementation and evaluation in real networks. We contrast the flow metrics against Reno and Cubic flows. The modified TCP is found to increase the goodput of short flows by more than 30% in typical settings with corresponding decrease in flow-completion-time without taking much bandwidth share from long flows. The conditional suitability of the algorithm for deployment in the Internet is endorsed.