Flowgrind - A New Performance Measurement Tool

During the last decades TCP and the networks it is used in steadily evolved. To aid further development it is crucial to give researchers measurement tools so they can evaluate and analyze their TCP modifications in real world network environments. In this paper we introduce the new measurement tool flowgrind. Unlike existing measurement tools, flowgrind's distributed architecture allows for an easy setup of complex scenarios. Besides the usual application perceived metrics it can also measure core variables from the operating system's TCP implementation thus enabling the researchers to analyze and understand the interactions between TCP and the underlying network.