LinuxCon+ContainerCon Europe 2016

During the last decades TCP and the networks it is used in steadily evolved. To aid further development it is crucial to give researchers and developers measurement tools so they can evaluate and analyze their TCP modifications in real world network environments. In this presentation we show our tool flowgrind. Unlike existing measurement tools, flowgrind's distributed architecture allows for an easy setup of complex scenarios (Fairness measurements with different congestion control mechanisms, cross-traffic, separation of test and control traffic etc.). Besides the usual application perceived metrics it can also measure core variables from the operating system's TCP implementation (tcp_info struct) thus enabling the developers to analyze and understand the interactions between TCP and the underlying network.