A cache device may be configured to disallow {HEAD ~ the transmission} of {TAIL ~ expired content}, and to contact the streaming server 100 in order to receive updated content 
of
A cache device may be configured to disallow { HEAD ~ the transmission } of { TAIL ~ expired content } , and to contact the streaming server 100 in order to receive updated content
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH