Getting the end user id address in asp.net

To get the end user's IP address, call this function.

protected string GetUserIPAddresss()
{
    string ip = string.Empty;
    if (Request.ServerVariables["HTTP_X_FORWARDED_FOR"] != null)
    {
        ip = Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
    }
    else if (Request.UserHostAddress.Length != 0)
    {
        ip = Request.UserHostAddress;
    }
    else
    {
        ip = HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];
    }
    return ip;
}

Thanks