Underwriters Laboratories (UL) Inc., 333 Pfingsten Rd., Northbrook, IL 60062, USA.
Department of Electrical Engineering, Northern Illinois University, 590 Garden Rd., DeKalb, IL 60115, USA.
Sensors (Basel). 2019 Dec 26;20(1):164. doi: 10.3390/s20010164.
The ZigBee wireless communication specifications forecast the use of multihop routes between nodes and define that nodes select their routes based on their costs. The specifications define how to compute a route cost from the probability of successfully transmitting on each of the routes' links; and it is recommended that such probabilities be obtained by counting received link status messages or averaging link quality indicators from received packets. In this paper, we study the performance of these two recommended procedures, show that they can lead to degraded route selections, and propose a procedure that can improve route selections without modifications to the ZigBee protocol or frame formats. Our procedure estimates the probability of successful transmission on each link, based on information from the medium access layer during unicast packet transmissions, and includes a modification into how ZigBee nodes treat routing messages internally in order to reduce variations in the link cost estimates. Focusing on a home environment with one or two hops, our simulation results show that, in several scenarios, our procedure performs better than either of the two procedures recommended in the ZigBee specifications.
ZigBee 无线通信规范预测节点之间将使用多跳路由，并定义节点根据成本选择路由。该规范定义了如何根据每条路由链路成功传输的概率计算路由成本；建议通过计算接收链路状态消息的数量或平均接收数据包的链路质量指标来获得这些概率。在本文中，我们研究了这两种推荐程序的性能，表明它们可能导致路由选择劣化，并提出了一种无需修改 ZigBee 协议或帧格式即可改进路由选择的程序。我们的程序基于单播数据包传输期间介质访问层的信息，估算每条链路成功传输的概率，并对 ZigBee 节点如何在内部处理路由消息进行修改，以减少链路成本估算的变化。我们的仿真结果集中在具有一个或两个跳的家庭环境中，结果表明，在几种情况下，我们的程序的性能优于 ZigBee 规范中推荐的两种程序中的任何一种。
