Research On Opportunistic Bulk Data Dissemination In Low-Duty-Cycle Wireless Sensor Networks

Wireless sensor networks are a kind of multi-hop and self-organizing wireless networks,composed of the randomly distributed integrated sensors,data processing units and communication modules,which have been widely used in various fields.Most of the sensor networks,once deployed,are intended to operate without attention for a long time.During the lifetime of the sensor networks,the user may need to fix the error code,reconfigure system parameters,update code for higher performance and so on.Because the size of the sensor network is relatively large,it is usually unfeasible to manually collect all nodes.Therefore,it is necessary to employ bulk data dissemination protocol to facilitate such tasks.This paper explores the design requirements and difficulties of bulk data dissemination technology,where energy efficiency and transmission efficiency are the most important considerations in designing bulk data dissemination protocols.In order to save energy,the wireless sensor networks usually use the duty cycle mode,so that the nodes can switch between the active mode and sleep mode.In order to enhance the transmission frequency,the researchers need to consider the various aspects of the factors of the network,such as network topology,node location,link quality and more.This paper first analyzes the advantages and disadvantages of Deluge protocol under the tiny OS system.First,we propose a bulk data dissemination benchmark protocol in the lowduty-cycle wireless sensor networks,called LDBD.LDBD draws on the data management technology and spatial multiplexing and pipelining of Deluge protocol.On this basis,we used the PW-MAC protocol to achieve the low-duty-cycle to save energy consumption.The competition negotiation mechanism is proposed to mitigate the hidden terminal problem.The channel reservation mechanism and the hardware response mechanism are used to ensure the reliability of data transmission.We also use overhearing mechanism to accelerate the dissemination process.Second,because the success rate of the competition negotiation mechanism of LDBD protocol is low in dense network,and the performance of the protocol is poor in late period,we propose the LDBD-NS protocol,whose negotiation mechanism is based on the node order.The LDBD-NS protocol will sort the candidate nodes according to the obtained data,which simplifies the negotiation process and ensures the success rate of the negotiation.The LDBD-NS protocol proposes the concept of node’s priority,which involves the location of the node in the network,the sending efficiency of the node,the ability of the node to obtain the data,and proposes the priority-based sender strategy to reduce the completion time.At the end of this paper,we simulate the LDBD protocol and LDBD-NS protocol,then analyze and compare both of them with the Deluge protocol.The results show that the energy consumption of both protocols proposed in this paper is much less than Deluge.LDBD-NS is better than Deluge in robustness,negotiation packets redundancy,dissemination completion time and so on.