# Improved Cell Allocation Strategies Using K-Means Clustering in Congested 6 TiSCH Environments
## 1 Introduction  
The Internet of Things (IoT) connects physical devices, enabling wireless sensor nodes to share environmental data and facilitate system interaction with the real world. Wireless sensor networks (WSNs) have gained interest for their diverse applications in analyzing environmental conditions and guiding appropriate responses [1]. 6 TiSCH addresses the needs of low-power wireless networks by ensuring end-to-end reliability and deterministic latency. It integrates IPv6 with IEEE802.15.4 time-slotted channel-hopping (TSCH), providing industrial-grade performance and seamless internet connectivity that are vital for the Industrial Internet of Things (IIoT) [2]. Therefore, the present work identifies and addresses the challenges in routing strategies and security management to enhance their efficiency and effectiveness while striving for greater simplicity in these areas [3, 4]. In IEEE 802.15.4's TSCH mode, limited broadcast opportunities occur at specific times and channels. Routers use enhanced beacon (EB) frames to announce the network; these EBs can include criticalinformation that allows new or long-sleeping nodes to make the most of these rare broadcasts, thereby ensuring efficient slot usage [5]. Scheduling techniques in TSCH networks vary, with some using centralized methods employing root node managing schedules and cell allocations and others using link-based schemes employing MAC addresses. However, current TSCH approaches may not meet future IIoT needs. Hence, more lightweight and energy-efficient scheduling and routing algorithms are necessary [6]. The 6 TiSCH architecture is crucial for the IIoT, ensuring reliable communication through effective cell allocation to prevent packet loss in high-traffic areas. In factories, field devices and sensors require high reliability and timely information exchange [7]. Efficient cell allocation based on node position directly influences network performance and power consumption [8]. Optimizing cell allocation in 6 TiSCH-based wireless sensor networks is essential for reliable data transmission, especially in densely deployed environments [9] comprising industrial automation, smart city infrastructure, and environmental monitoring implementations. This work employs the K-means algorithm for label-free clustering to optimize cell allocation in 6 TiSCH networks by clustering nodes based on their spatial distribution and link performance, which helps to avoid the need for further iterations. Centroid nodes are designated as cluster heads and other nodes are associated with the nearest center, resulting in reduced transmission hops, simplified neighbor discovery, and enhanced scalability. This clustering strategy informs a dynamic cell allocation approach within the slot frame, which improves communication efficiency and minimizes collisions. Our proposed method efficiently manages intra-cluster subchannel allocation and inter-cluster interference through distributed learning, which optimizes cell utilization, reduces overhead, and enhances overall network efficiency. This optimization is reflected in the network topology, where parent nodes function as cluster heads and sink nodes serve as data collection centers. Dynamic cell allocation within each cluster is guided by communication demands and traffic density, thereby minimizing congestion and improving transmission efficiency. Furthermore, routing paths and network organization are determined by RPL while considering factors such as OF0 and MRHOF. Network performance is assessed based on the joining time, packet delivery ratio, end-to-end latency, and throughput. By maintaining a constant number of nodes, this study prioritizes the evaluation of clustering and cell allocation strategies while accounting for the static conditions typical of industrial and IIoT environments [10]. Our goal is to enhance resource utilization in 6 TiSCH networks and to reduce packet loss based on the node distribution.