Jay R. Wren – lazy dawg evarlast

I just published an application which I consider useful over on codeplex with source hosted on launchpad.

http://wlanchannelinfo.codeplex.com/

https://code.edge.launchpad.net/~evarlast/+junk/WlanChannelInfo

I wrote this because Wifi in my home is very slow. Its so slow I’m tempted to run a network cable to my couch so that even when I’m couch surfing I can have fast access to my server.

In an effort to diagnose my slow Wifi, I tried to see if my neighbors were causing interference by running Wifi on the same or overlapping channel as me. I downloaded netstumbler; it didn’t work. I downloaded some other tool; neither did it.

So I wondered how hard it would be to write my own. It turns out Windows 7 added to the Wlan* api to expose all of the necessary data. After some digging I found the managedwlan project on codeplex. Now I got to play.

Once I figured out the api, I was able to write the entire application with pretty much one LINQ expression:

var client = new WlanClient();
var retval =
from wlanIface in client.Interfaces
from bssentry in wlanIface.GetNetworkBssList()
from network in wlanIface.GetAvailableNetworkList(Wlan.WlanGetAvailableNetworkFlags.IncludeAllAdhocProfiles)
where InterfaceService.GetStringForSSID(network.dot11Ssid) == InterfaceService.GetStringForSSID(bssentry.dot11Ssid)
select new WifiInfo
{
bssentry = GetStringForSSID(bssentry.dot11Ssid),
channel = Wifi.FrequencyChannelMap[bssentry.chCenterFrequency],
frequency = bssentry.chCenterFrequency,
linqQuality = bssentry.linkQuality,
strength = bssentry.rssi,
signalQuality = network.wlanSignalQuality,
wifitype = network.dot11BssType
};

The result of that expression is directly databound to a WPF DataGrid and I can now view the data that I want to.

I really love the platform (C#+.NET) on which I work.