{HEAD ~ The hash values} for the connections detected during the predetermined time period preceding {TAIL ~ the current time period} are stored in the second table 
{ HEAD ~ The hash values } for the connections detected during the predetermined time period preceding { TAIL ~ the current time period } are stored in the second table
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH