zhuan: WAN simulating tool - Netem : command tc qdisc

Last weekly meeting we talked about a WAN simulating tool in order to test WPG, I find a great tool that will help us to simulate a WAN connection called 「 Netem 」, a module within the Linux traffic control facilities. The current version of Netem provides network emulation functionality for testing protocols by emulating the properties of wide area networks and also emulating variable delay, packet loss, duplication, re-ordering and bandwidth limitations. Netem is controlled by the command line tool 'tc'

The picture below shows the 2 most common configurations for a Netem box:

For more information please follow the links below.

 

http://www.linuxfoundation.org/collaborate/workgroups/networking/netem

http://tdistler.com/2011/06/10/netem-wan-emulation-how-to-setup-a-netem-box

http://www.linuxforu.com/2012/06/bandwidth-throttling-netem-network-emulation/