Using BindIPEndPointDelegate to specify the source port doesn't seem to work

Question

I've searched all over on how to use BindIPEndPointDelegate to change the source port of my HttpWebRequest. I have found multiple posts on this:

Here and Here

However, It doesn't seem to be working for me. I found the same issue with this guy: Define Outgoing/Calling Port for SOAP Web Service in Visual Studio 2010

Basically, I want to change my source port when connecting to a webpage. BindIPEndPointDelegate is pretty straigh forward.

HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);
 req.ServicePoint.BindIPEndPointDelegate = (servicePoint, remoteEp, retryCount) =>
             {
                 return new IPEndPoint(IPAddress.Any, 8086);
             };

When I look at the connections with netstat -n, I expect to see myipaddress:8086 as the source and the destination IP:80. What I see in netstat is that it is creating a loopback (127.0.0.1:8086) with my specified port. See screen shot of netstat -n

Since this is my first post, I can't post images. So the image can be found here

Why does BindIPEndPointDelegate create a loop back connection and how can I get my WebRequest to behave like the browser with my specified port?

I'm on a win7 Pro box, No local firewall, Not going through a proxy.

Answer 1

I had a similar problem today. I selected a particular source port in the BindIPEndPointDelegate, but with WireShark I always saw a different source port than what I selected. Then I discovered that I was implicitly using a Proxy by using the Fiddler2 Web Debugger. Once I turned off Fiddler, then I started seeing the source port numbers in WireShark that I requested in the Bind delegate.

The upshot is that if you have a proxy anywhere you might see this same behavior.