Validation parameters

In the Virtual User Parameters box, the Validation parameters group box makes it possible to modify the operational conditions of the validation process:

Load Generator

By default, the localhost Load Generator is used for the Virtual User validation. It may be necessary however to use a remote Load Generator instead. For example, changing the local Local Generator for an remote one can be required to access an application stored in a secured environment.

The Load Generator drop-down list allows checking the Virtual User with one of the Load Generators available in the test scenario.

Cache management

Initializing the cache when the Virtual Users are started can be defined in three behaviors in the Handle Cache drop-down list:

Browser profile

The Browser dialog makes it possible to define a browser profile used by the selected User Path. It may prove relevant to use a specific browser profile for a load test when the content of the server response depends on the browser used.

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The Available browser profiles list makes it possible to select one of the following profiles:

When a browser profile is selected, the Parameters group box displays its default and additional parameters:

Network conditions

A click on the picker button of the WAN Emulation field displays the WAN Emulation dialog box.

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The WAN Emulation function is useful to simulate degraded network conditions with latency periods and packet loss percentages.

In the WAN Emulation dialog box, the Available WAN Emulation profiles list makes it possible to select one of the following profiles:

The values for the network conditions applicable in the tests are configured in the Parameters group box.

A click on the OK button closes the WAN Emulation box.

Measure network characteristics from a computer

The easiest way to measure the latency and packet loss rate between a computer and a server is to use the ping command with enough requests to get a reliable number of packets lost. For example ping –n 100 www.myserver.com to send 100 packets.

When each packet has been sent, the program displays the statistics for response times (latency) and the number of packets sent, received and lost.

The latency given is a round-trip latency. It is necessary to divide the measure by two to get a sound approximation of upload and download latency.

Measure network characteristics from a mobile device

A number of free mobile applications are available on mobile stores to send the same Ping commands as it can be done on computers. For example, Free Ping is one application on iOS.

These programs displays the statistics for response times (latency) and the number of packets sent, received and lost.

The latency given is a round-trip latency. It is necessary to divide the measure by two to get a sound approximation of upload and download latency.