
Chapter 18: Wireless Local-Area Networking
Using WLANEx to Obtain Network Information
Psion Mobile Devices Developers Guide
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18.7 Using WLANEx to Obtain Network Information
While the primary purpose of the WLANEx namespace is to programmatically configure and control a
network connection, you can also use it to obtain network information from the surrounding access points.
This information is available even when the device is not connected to the network.
Received Signal Strength Indicator—RSSI
The RSSI status of the radio changes continuously based on a number of different environmental factors,
such as distance, interference, and the antenna angle. The RSSI is measured in dBm. A perfect signal is
-10 dBm. An complete absence of signal is -200 dBm.
Network adaptor Name
The network adaptor name can be queried using the Mobile Devices SDK. The string returned is the same
as the adaptor name returned by the GUI application on the device.
Summit Supplicant and WireLess Zero Configuration Supplicant
Using these supplicants you can obtain from the surrounding networks: their SSIDs, their RSSIs, and the
encryption modes that are needed to associate with them.
DeviceScape Agent Supplicant
This supplicant can obtain more dynamic network information than the other supplicants can. The precise
information depends on the access points. The most common items returned are: BSSID, SSID, frequency,
flags (type of encryption), whether, or not, the device is associated with an access point.
18.8 Summit Radio Features
Radios manufactured by Summit behave differently from the other radios. Summit radios operate in one of
the following modes:
• Summit mode.
• Wireless Zero Configuration mode—referred to as Third Party Config mode.
Summit Mode
When operating in this mode, the Summit radio does not appear on the list of radios controlled by the GUI
Wireless applet. Instead it is controlled by the GUI Summit applet.
The preferred list of access points is not available, so the radio cannot roam between networks; however, it
can roam between access points on the same network.
Wireless Zero Config Mode (WZC)
When operating in this mode, the Summit radios behave in the same way as all the other radios that
are available. See Section Wireless Zero Config on page 191.
Changing Between Modes
When the operating mode of a Summit radio is changed between Summit mode and Wireless Zero Config
mode, the radio must be reset by powering it down, and then powering it up.
18.9 Controlling Power on all Supplicants
18.10 Configuring WLAN Through the User Interface
The following utilities can be used to configure WLAN connections:
• Wireless Zero Config (WZC)
• Wi-fi Config
• Summit Client Utility (SCU)
• Odyssey Access Client (OAC) by Juniper Networks
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