This link will be of interest to you: http://msdn.microsoft.com/en-us/library/ds8bxk2a.aspx
For http connections, the WebRequest and WebResponse classes use SSL to communicate with web hosts that support SSL. The decision to use SSL is made by the WebRequest class, based on the URI it is given. If the URI begins with "https:", SSL is used; if the URI begins with "http:", an unencrypted connection is used.