Simulating high latency / intermittent network connections

Question

I'm load testing a network application using The Grinder (on a Windows PC) and I wish to simulate imperfect network conditions in order to see what effect is has on the application load, in particular I'd like to see the effect of:

• Variable network latency, so not only do different clients have different latency, but also latency may vary during the test for a single client.
• Dropped network connections - I wish to simulate what happens when a network connection is abruptly / randomly dropped.

What's the easiest way of doing this?

Answer 1

1. Setup a Linux box as the default router for this machine.
2. Install 'netem' on the linux box: http://www.linuxfoundation.org/collaborate/workgroups/networking/netem

Answer 2

Other options:

• WanEM (OpenSource, clock timing can be a challenge in the default VM install which produces inconsistent results. Best used wen installed on physical hardware instead of within a virtual machine) WanEm Download location
• Shunra (Commercial, My preference in a chassis solution) Shunra Products
• Anue (Commercial, now Ixia) Anue on Ixia Website