A method of implementing {HEAD ~ a storage function} in {TAIL ~ a passive optical network system} 1, further including a groupcast LINK ID allocation step; in said optical line terminal, allocating a groupcast LINK ID to data requiring storage; and sending said data requiring storage with a broadcast method to all the optical network units 
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A method of implementing { HEAD ~ a storage function } in { TAIL ~ a passive optical network system } 1 , further including a groupcast LINK ID allocation step ; in said optical line terminal , allocating a groupcast LINK ID to data requiring storage ; and sending said data requiring storage with a broadcast method to all the optical network units
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH