A first session is established between the log in server and {HEAD ~ the subscriber server} to validate {TAIL ~ the registrant identification data}, and to generate a session password 
to validate
A first session is established between the log in server and { HEAD ~ the subscriber server } to validate { TAIL ~ the registrant identification data } , and to generate a session password
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH