Adaptive buffering scheme to reduce packet loss on densely connected WSN with mobile sink

A buffer overflow at a network node occurs if the sum of the amount of data it generates and the amount of data it receives from upstream nodes exceeds its transmission throughput. Densely connected wireless sensor networks (WSNs) with intermittently available sinks (such as mobile sinks) strongly inherit such a buffer overflow problem as sensor nodes in WSNs have limited buffering capacity, and the intermittent nature of these sinks can further influence the network throughput. We propose distribution and caching of sensor-generated data at sensor nodes that belong to any of the minimum cost paths leading to a mobile sink path. We further propose to store the data at each source node for a certain period of time instead of immediately forwarding them to the downstream nodes so as to reduce unnecessary network congestion. Both mathematical and simulation evaluation show that these schemes significantly reduce packet loss probability at network of any size. Consequently, the amount of information lost in the system due to packet overflow/retransmission will be significantly reduced.