Priority control using multi-buffer for DTN

DTN (delay/disruption-tolerant networking) is a network enabling data to be carried end-to-end without continuous connection. DTN uses a store and forward method, in which a node stores the data when no other nodes exist in a communicable range and forwards a copy of the data when they do. Since the buffer has a limited buffering capacity, the data often need to be dropped. When there are data that have different priorities, the high priority data may be pushed out from the buffer by the low priority data. Thus the high priority data arrival rate lowered by pushing data out needs to be increased. In this paper, we propose and evaluate a buffer control system to raise the high priority data arrival rate without decreasing the total arrival rate when the buffer has a limit. The priority control system avoids the high priority data dropping caused by low priority data by choosing the dropped data in reference to the data priority when the new data are sent to the full node. We show that the priority control system increases the high priority data arrival rate and maintains the high priority data drop rate at no more than the desired value.