Signal Strength

To assess how much signal strength a client receives is not difficult, especially when you use Cisco clients. Each Cisco client is equipped with Cisco Aironet Desktop Utility (ADU). (We covered these utilities in more detail in Chapter 6, "Configuring Clients.")

If you open the tool and select Site Survey, ADU shows two important metricssignal strength and signal quality, as illustrated in Figure 12-1. The most important part of this screen is Overall Link Quality, which gives you a simple assessment of your connection to the WLAN.

Figure 12-1. ADU's Site Survey Tool

The site survey tool is helpful not only when you analyze a client's ability to connect to the WLAN; it also helps when you perform a site survey. It's easy to find the best (and worst) reception by carrying around your organization a laptop equipped with a wireless interface and ADU.

You can use the Site Survey component of ADU to help monitor your WLAN's performance and better position APs and clients. This is accomplished with two different site survey modes:

• Passive mode The site survey does not send out traffic. It simply listens to other RF network traffic, and displays signal strength and quality.

• Active mode The site survey exchanges packets with the AP.

The default action for the site survey is in passive mode. However, to engage active mode, click Setup to configure active mode, and then click Start to run the test. When the test has ended, the site survey tool returns to passive mode (or you can click Stop). This can help you assess your client's transmitting and receiving abilities.

The site survey tool using ADU is covered in more depth in Chapter 5, "Installing and Configuring Access Points."