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The Internet of Things (IoT) is largely built on the interconnection of low‐power networked devices, generally referred to as low‐power and lossy networks (LLNs). The prime routing protocol designed over IPv6, named routing protocol for LLNs (RPL), presents the main effort to standardize an IPv6‐based routing protocol for all LLNs. Routing protocol for LLNs has gained significant prominence in IoT research due to its flexibility in adapting to different topologies and could run in agnostic replicas over the same network to serve different applications. However, as RPL is based on virtualizing a tree topology, many challenges ensue in scaling with network traffic and diverse traffic patterns in the IoT. The current RPL standard focus on operation under a single sink, toward which all traffic flows, and thereby its survivability determines the lifetime of the IoT network. However, it mentions briefly in its RFC6550, the using of multiple roots. However, it does not study when, where, and how deploying multiple roots. In this paper, we propose a dynamic Rescue Sink protocol, which actively monitors the performance of IoT nodes in a given RPL network and introduces a dynamic mechanism for mitigating RPL performance by introducing new sinks when needed. We define a suffering index computed over intervals by RPL nodes in a decentralized approach, which monitors their tendency to yield high traffic load without inducing control overhead. Furthermore, our Rescue Sink protocol is designed in line with the RPL standard, and we elaborate on all the components to integrate with the standard. We present a thorough evaluation of our Sink Rescue protocol, using the Cooja simulator over the Contiki OS, most prevalently used in IoT devices. We demonstrate the performance improvements in terms of energy consumption and data delivery.

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Bioaugmentation by Pseudomonas strains is widely used for the removal of pollutants in wastewater. In this study, we aimed to determine the removal of pentachlorophenol (PCP, 800 mg·L^–1) in secondary wastewater by the bioaugmentation process. We determined the effects of using three surfactants, namely sodium dodecyl sulfate (SDS), cetyl-tri-methyl-ammonium bromide (CTAB), and Tween 80 for PCP removal. We determined the effect of the role of PCP surfactant for the biofilm and auxin production of the selected bacterial strain of <em>P. fluorescens</em> GU059580. High-performance liquid chromatography and spectroscopic analysis were used to determine PCP removal and bacterial growth, respectively. Biofilm production was determined using 96-well polystyrene plates, and auxin production was determined using spectrophotometric measurement at 535 nm. The results showed the removal of PCP from wastewater by <em>P. fluorescens</em> GU059580 is about 90.12%. The PCP removal from wastewater showed an improvement of about 96.5% after the addition of Tween 80, whereas significant biofilm formation was found in the mineral liquid medium supplemented with PCP and Tween 80, with a value of 3.78. The highest concentration of auxin was found in the presence of PCP without surfactants, showing a value of 1.7 mg·L^–1. To conclude, <em>P. fluorescens</em> GU059580 can be used in bioreactors or some specific wastewater treatment processes for bioremediation.