LEDBAT++ is the evolution of LEDBAT, a congestion control algorithm originally designed to provide lessthan-
best-effort transport on the Internet. LEDBAT++ aims to address a number of shortcomings present in
LEDBAT, including late-comer advantage, latency drift, competition on equal grounds with best effort traffic
in the presence of small buffers and difficulties experienced while measuring the variations on the delay.
In this paper, we perform an experimental evaluation of LEDBAT++ using the Windows Server’s LEDBAT++
implementation. We find that while LEDBAT++ overcomes all the limitations identified in LEDBAT, the change
introduced in LEDBAT++ to do so results in a performance penalty that prevents LEDBAT++ flows to seize
all the available capacity when there is no competing traffic. We propose two simple modifications to the
LEDBAT++ algorithm that would address the identified issues and reduce the penalty.This work has been partially supported by the EU EC through the NGI Pointer RIM project, Grant 871528 , and the Madrid Government (Comunidad de Madrid-Spain) under the Multiannual Agreement with UC3M in the line of Excellence of University Professors (EPUC3M21), and in the context of the V PRICIT (Regional Programme of Research and Technological Innovation)
