An INT-based TCP window modulator for congestion control in data center networks

Abstract

Modern data centers carry a huge number of diverse services and applications, which are developed by Transmission Control Protocol (TCP). The early TCP versions, such as Reno, were designed decades ago and not efficient enough to accommodate the data center environment, especially congestion control algorithms (CCAs). Data center TCP (DCTCP) was the classical CCA, which proposed for the data center networks (DCNs). All the conventional CCAs use packet loss and/or delay as congestion signals, however, these signals are not accuracy enough to conduct the CCAs to compute appropriate congestion window. In this paper, the In-band Network Telemetry (INT) data is used as congestion signal. The INT data can indicate the congestion location and level, which is more accuracy than end-to-end signals. Based on the advanced signal, an INT-based Receiver-driven TCP congestion window modulator, named IRTCP, is proposed and implemented as a loadable Linux kernel module, without any modification of the TCP/IP stack. Either in small-scale Mininet emulation or in large-scale NS3 simulation, the results show that IRTCP could provide significant performance improvement. The average FCT of IRTCP for mice flows is about 89.5%, 91.6%, 91.7% lower than Cubic-RED, Cubic-FIFO, and DCTCP. The average throughput of IRTCP for elephant flows is about 11.5%, 31%, 20.6% higher than DCTCP, Cubic-RED, Cubic-FIFO.