Reliable Wireless Multi-Hop Networks with Decentralized Slot Management: An Analysis of IEEE 802.15.4 DSME
Wireless communication is a key element in the realization of the Industrial Internet of Things for flexible and cost-efficient monitoring and control of industrial processes. Wireless mesh networks using IEEE 802.15.4 have a high potential for executing monitoring and control tasks with low energy consumption and low costs for deployment and maintenance. However, conventional medium access techniques based on carrier sensing cannot provide the required reliability for industrial applications. Therefore, the standard was extended with techniques for time-slotted medium access on multiple channels. In this paper, we present openDSME, a comprehensive implementation of the Deterministic and Synchronous Multi-channel Extension (DSME) and propose a method for traffic-aware and decentralized slot scheduling to enable scalable wireless industrial networks. The performance of DSME and our implementation is demonstrated in the OMNeT++ simulator and on a physically deployed wireless network in the FIT/IoT-LAB. It is shown that in the given scenarios, twice as much traffic can be delivered reliably by using DSME instead of CSMA/CA and that the energy consumption can be reduced significantly. The paper is completed by presenting important trade-offs for parameter selection and by uncovering open issues of the current specification that call for further effort in research and standardization.
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