Resource aware reliable transport layer protocol for wireless sensor network

In this paper, PSFQ and its improved version of PSFQ, GARUDA and RBC is explored and a new transport layer protocol for WSN called Resource aware reliable transport protocol for wireless sensor network is proposed and evaluated. By analyzing PSFQ and improved PSFQ it is found that, the retransmission of missing data is initiated based on the NACK. The collated NACK is transmitted to the immediate one hop previous neighbor and the neighbors respond to the NACK by sending the missed data packet. The point here to note is that, the collated NACK packet alone is transmitted, which leads to the wastage of resource. Therefore to reduce the wastage of resource, the idea is that, instead of sending the consolidated NACK alone as single packet, the NACK can be combined, that is appended, along with data packets flowing in the upstream direction. To perform this, the following modification is performed in PSFQ. Both the data and NACK are stored in separate queues. If NACK is present in NACK queue, then it is appended along with the data packet in the data queue, and then it is forwarded to the neighbor nodes in the upstream direction. Average latency, average delivery ratio, average delivery overhead, and energy consumption is measured and presented.