I've been having a problem with configuring corporate laptops to use our proxy server. The problem is this.....Our adjusters are always connecting wirelessly at hotels and airports. I have their browsers pointing to our public web server to get a .pac file. (ex. - mycompany.com/proxy.pac). On a normal network, this is fine because once they get connected, the browser is able to gain access to the .pac file and instruct the browser to surf through the proxy. The same rule would apply if I explicitly defined the proxy in IE. (ex. - "Use a Proxy Server for your Lan" in IE options). In a lot of hotels, they make you register your session or click "I accept" to connect for a 24-hour period. If you do not click that, then you will not be able to get out their gateway. The user never sees this page because the proxy server cannot be reached since the gateway is usually blocked at a hotel. They have to turn the proxy server setting off to get the hotel's welcome page. Of course, this is not desirable since it leaves the comptuer wide open.
With that, I decided to write a .pac file that would reside locally on the laptop. The script basically says if you can ping our corporate domain, then set PROXY. If you cannot, then go DIRECT. Here is the script.
--------------------
function FindProxyForURL(url, host)
{
// variable strings to return
if (isPlainHostName (host) ||
dnsDomainIs(host, ".mydomain.com") ||
isResolvable(host))
return "PROXY proxy.mydomain.com:9999";
else
return "DIRECT";
}
--------------------------
----
I configured IE "to use the following script" in LAN Settings. It points to a local directory, such as file://c:/windows/proxy.pa
c. This way, the file is always accessible. This works beautifully on any normal network that doesn't redirect you. I've tested it on our outside bellsouth wireless network that we use at headquarters. It works perfectly. At a hotel, I have inconsistencies and I don't understand why. On some networks, the script will work. On others, it will go the hotel's welcome page and then I can connect to my home page. When I test the proxy with known blocked websites, it doesn't work. It's as if IE doesn't see the proxy setting at all. It allows the user to go to any website and doesn't block anything I can ping our company domain, so it should set the proxy server in the registry. I even changed the browser setting to specifically go to my proxy server (ex. - proxy.mydomain.com:9999), and it still allowed the user to go to any website. What is the difference between the hotel's wireless network and a regular wireless network? Why does IE not proxy when it is defined in the settings? Is there something about establishing that internet session with the hotel that changes how IE behaves?
Start Free Trial
