Link dynamics due to environmental change is a critical challenge for wireless networking, and handling it is essential for wireless protocols, especially for low-power and lossy multihop wireless networks (LLNs). Prior work have only studied methods to detect and cope with short-term and long-term link dynamics in LLN. In this work, we tackle the midterm dynamics due to the opening and closing of doors and windows that can happen in a time scale of a few minutes to hours in an indoor LLN. Specifically, we study how midterm link fluctuations impact the performance of standard IPv6 routing protocol for LLN (RPL), and design ‘RPLIE,’ a novel and backward-compatible lightweight enhancement to RPL that detects and overcomes the negative impact of such dynamics. We define ‘opportunistic links’ and propose a novel routing metric, expected breakage cost (EBC), which represents the expected number of link transmissions required from a link breakage to a routing parent change. We implement RPLIE on real embedded devices, and evaluate its performance against the standard RPL via experiments on a 31-node testbed to show that RPLIE achieves significantly better packet delivery performance while using less overhead.

中文翻译：

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RPLIE：中期链路波动下室内环境的RPL

由于环境变化引起的链路动态是无线网络的一个关键挑战，处理它对于无线协议至关重要，尤其是对于低功耗和有损多跳无线网络 (LLN)。之前的工作只研究了检测和处理 LLN 中短期和长期链接动态的方法。在这项工作中，我们解决了由于在室内 LLN 中可能在几分钟到几小时的时间范围内打开和关闭门窗而导致的中期动态。具体而言，我们研究中期链路波动如何影响 LLN (RPL) 的标准 IPv6 路由协议的性能，并设计“RPLIE”，这是一种新颖且向后兼容的 RPL 轻量级增强，可检测并克服此类动态的负面影响。我们定义了“机会链接”并提出了一种新的路由度量，预期中断成本 (EBC)，表示从链路中断到路由父更改所需的预期链路传输次数。我们在真实的嵌入式设备上实施 RPLIE，并通过在 31 节点测试台上的实验评估其与标准 RPL 的性能，以表明 RPLIE 在使用更少开销的情况下实现了显着更好的数据包传输性能。