Since the referencing of {HEAD ~ the index nodes} 55 a c and storage nodes 56 a e is performed indirectly, for instance, by using Equations and , the structure of {TAIL ~ the message store} 50 can be changed dynamically 
Since the referencing of { HEAD ~ the index nodes } 55 a c and storage nodes 56 a e is performed indirectly , for instance , by using Equations and , the structure of { TAIL ~ the message store } 50 can be changed dynamically
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH