In cooperation with the network R&D team of NetApp (http://www.netapp.com), COMSYS offers a software lab in the area of datacenter and enterprise networking. The students will work on the development of the open source performance network measurement tool flowgrind (http://github.com/flowgrind/flowgrind).

Flowgrind is a testing and benchmarking tool to measure throughput and other metrics for TCP. In contrast to similar tools like iperf or netperf it features a distributed architecture, where throughput and other metrics are measured between arbitrary flowgrind server processes.

Flowgrind measures besides goodput the application layer interarrival time (IA)T and 2-way delay (RTT), blockcount and network transactions/s. Unlike most cross-platform testing tools, flowgrind can output some transport layer information, which are usually internal to the TCP/IP stack. For example, on Linux this includes the kernel's estimation of the end-to-end round-trip time and the size of the TCP congestion window and slow start threshold.

The traffic generation itself is either bulk transfer, rate-limited, or sophisticated request/response tests. Flowgrind uses libpcap to automatically dump traffic for qualitative analysis.

Goal of the software lab is the further improve the performance of flowgrind (e.g. 40 Gbit/s Ethernet) as well as to integrate new features like 1-way delay measurements under load.

Requirements are:

• Strong C coding experience; other languages and toolchains are a plus
• Knowledge of Linux or BSD network stack internals
• Knowledge of TCP/IP networking

In your application, please state which experience/knowledge you have.