ABSTRACT
Existing duty-cycling and pipelined-forwarding (DCPF) protocols applied in battery-powered wireless sensor networks can significantly alleviate the sleep latency issue and save the energy of networks. However, when a DCPF protocol applies to a linear sensor network (LSN), it lacks the ability to handle the bottleneck issue called the energy-hole problem, which is mainly manifested due to the excessive energy consumption of nodes near the sink node. Without overcoming this issue, the lifespan of the network could be greatly reduced. To that end, this paper proposes a method of deploying redundant nodes in LSN, and a corresponding enhanced DCPF protocol called redundancy-based DCPF (RDCPF) to support the new topology of LSN. In RDCPF, the distribution of energy consumption of the whole network becomes much more even. RDCPF also brings improvements to the network in terms of network survival time, packet delivery latency, and energy efficiency, which have been shown through the extensive simulations in comparison with existing DCPF protocols.
ABSTRACT
Data exchange patterns between nodes in WorldFIP fieldbus network are quite important and meaningful in improving the communication performance of WorldFIP network. Based on the basic communication ways supported in WorldFIP protocol, we propose two patterns for implementation of data exchange between peer nodes over WorldFIP network. Effects on communication performance of WorldFIP network in terms of some network parameters, such as number of bytes in user's data and turn-around time, in both the proposed patterns, are analyzed at length when different network speeds are applied. Such effects with the patterns of periodic message transmission using acknowledged and non-acknowledged messages, are also studied. Communication performance in both the proposed patterns are analyzed and compared. Practical applications of the research are presented. Through the study, it can be seen that different data exchange patterns make a great difference in improving communication efficiency with different network parameters, which is quite useful and helpful in the practical design of distributed systems based on WorldFIP network.
