Netem - emulating real networks in the lab
This paper covers "Netem" a network emulator built with the Quality of Service (QOS) network queuing discipline support in Linux. Many applications and protocols work fine over local area networks but have problems when running over the Internet.
"Netem" started out as a simple tool to test alternative TCP congestion algorithms but has grown to provide lots of interesting features. Unlike earlier monolithic network emulator such as NISTnet and DummyNet it only has to provide network perturbations. By using other parts of the queuing system, complex emulations can be built of simple components much as filters can be built with shell and pipes.
Stephen Hemminger has over 20 years experience with computer systems. He has worked on Unix kernel and networking at Mitre, Tektronix, and Sequent. He also has experience with video servers (nCube), database replication (Informix) and did the .com thing at two DRM companies that imploded (Passedge then InterTrust). At OSDL, he participates in the Data Center Linux (DCL) initiative and works on networking issues. He is the maintainer for Ethernet Bridging, Iproute2 tools, and IPV6 DHCP.
Mr. Hemminger holds a Master's degree in Engineering from Thayer School of Engineering at Dartmouth.