How can I generate 1 Gbit/s traffic for a webserver?

Well, creating a constant stream of 1Gbit/s from a webserver is an impressive task :-)

• 1. You need a webserver (or a webserver farm with load balancer) that is able to deliver 1 Gbit/s.
• 2. You need a network infrastructure (switches etc.) that is able to handle this load.
• 3. You need one (or several) test clients running Webserver Stress Tool to create the necessary HTTP requests

In most cases one client will not be enough. But you can of course create any load using several copies of Webstress on several PCs.

It's almost impossible to say in advance how many instances/PCs you would need for a specific load - there are so many parameters that will influence this:

• Number of URLs requested: make it as small as possible to avoid the lower bandwidth usage that occurs during the protocol/session handling phases of the HTTP requests
• Average size of the requests: make it as large as possible (several hundred kilobytes) so that
• Number of simulated users: Stay between 100 and 300 simulated users per Webstress instance (this avoids that threads have to wait for each other too much and maximizes the load generated by the webstress instance)
• Clicktime ("think time") between clicks: Turn this to zero (as soon as one simulated user has finished one request, the next one is sent immediately)

The disadvantage of running several instances of webstress is that you can not consolidate the results into one big results set. You need to run external monitoring tools (like PRTG Network Monitor) to monitor the consolidated load and bandwidth.

More info about Webserver Stress Tool