However, {HEAD ~ the authentication device} or method may also be used to authenticate a user to the remote service, or indeed, mutually authenticate {TAIL ~ a remote service} and a user 
However , { HEAD ~ the authentication device } or method may also be used to authenticate a user to the remote service , or indeed , mutually authenticate { TAIL ~ a remote service } and a user
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH REL REL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH