Finishing Flows Faster with A Quick congestion Control Protocol (QCP)
Debessay Fesehaye · 2013
The transmission control protocol (TCP) is the major transport protocol in the Internet. TCP and its variants have the drawback of not accurately knowing rate share of flows at bottleneck links. Some protocols proposed to address these drawbacks are not fair to short flows, which are the majority of the Internet traffic. Other protocols result in high queue length and packet drops which translate into a high average flow completion time (AFCT). In this paper we present the design and analysis of a Quick congestion Control Protocol (QCP). QCP can quickly give flows their fair share rates hence allow them to quickly finish. Unlike existing schemes, QCP uses an accurate formula to calculate the number of flows sharing a network link. This enables QCP to get fair share rates to flows without over or under-utilization of bottleneck link capacities. We also present an efficient sharing mechanism which QCP uses to assign capacity which is not used by some flows bottlenecked elsewhere to other flows which need the capacity. We show how QCP can be implemented by extending the emerging OpenFlow architecture. Simulation results confirm the design goals of QCP in achieving reduced AFCT (by upto 30%).