  In data centers, the nature of the composite bursty traffic along with the
small bandwidth-delay product and switch buffers lead to several congestion
problems that are not handled well by traditional congestion control mechanisms
such as TCP. Existing work try to address the problem by modifying TCP to suit
the operational nature of data centers. This is practically feasible in private
settings, however, in public environments, such modifications are prohibited.
Therefore, in this work, we design simple switch-based queue management to deal
with such congestion issues adequately. This approach entails no modification
to the TCP sender and receiver algorithms which enables easy and seamless
deployment in public data centers. We present a theoretical analysis to show
the stability and effectiveness of the scheme. We also present, three different
real implementations (as a Linux kernel module and as an added feature to
OpenvSwitch) and give numerical results from both NS-2 simulation and
experiments of real deployment in a small test-bed cluster to show its
effectiveness in achieving high throughput overall, a good fairness and short
flow completion times for delay-sensitive flows.
