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