XAgent is an XStudio agent running in background on a windows, linux or MacOSX host. It's pretty straightforward to execute campaign sessions on remote computers:
1. Install XAgent on the host you wish to remotely execute (now or scheduled) your tests
2. When creating a campaign session (or a schedule) from XStudio just select this host

Although the details on how to install the whole test automation framework are described in the official documentation, the installation of XStudio is pretty straight forward and can be summarized in only a few steps:
1. Download and install the latest Java Runtime Environment (JRE) (Java 6 and higher is required)
2. Download and install the latest version of MySQL from here
3. Create an empty database and create a user account granted with all appropriate rights on this database
4. Download MySQL's jdbc connector
5. Download XStudio from here
6. Run setup_xstudio_v1_2_ix86_win32.exe program
7. Copy the connector jar in C:\Program Files\XQual\XStudio\bin\jdbc8. Run XStudio

The complete infrastructure includes several components. In a small scale environment, all the components will be installed on a single computer. On larger organizations, the components will be installed on different computers. You have first to decide what configuration fits the best your organization. Of course, if in the future you need to change the configuration, only a few changes will be necessary.

One thing to remember: it does not make sense to install XStudio and XAgent on the same computer since XStudio "includes" natively XAgent.

Access to XStudio is restricted to users who have suitable credentials. A login process is used to authenticate the user before he can use the system. Each user is then granted with a list of permissions.

The license of this software is Freeware, you can free download and free use this remote access software.