get actual ip address of system using asp.net

Revision 1
I want to get user ip address for my application. I am using following code as

txtip.Text = HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];

but it always return 127.0.0.1 but my actual ip address is 192.0.0.110. I want this ip to be returned using coding in asp.net .

Please any one help me soon. I have to finish the task.

Thanks in advance.