The Semantic Web technologies have been used in the Internet of Things (IoT) to facilitate data interoperability and address data heterogeneity issues. The Resource Description Framework (RDF) model is employed in the integration of IoT data, with RDF engines serving as gateways for semantic integration. However, storing and querying RDF data obtained from distributed sources across a dynamic network of edge devices presents a challenging task. The distributed nature of the edge shares similarities with Peer-to-Peer (P2P) systems. These similarities include attributes like node heterogeneity, limited availability, and resources. The nodes primarily undertake tasks related to data storage and processing. Therefore, the P2P models appear to present an attractive approach for constructing distributed RDF stores. Based on P-Grid, a data indexing mechanism for load balancing and range query processing in P2P systems, this paper proposes a design for storing and sharing RDF data on P2P networks of low-cost edge devices. Our design aims to integrate both P-Grid and an edge-based RDF storage solution, RDF4Led for building an P2P RDF engine. This integration can maintain RDF data access and query processing while scaling with increasing data and network size. We demonstrated the scaling behavior of our implementation on a P2P network, involving up to 16 nodes of Raspberry Pi 4 devices.

翻译：语义网技术已被应用于物联网（IoT）中，以促进数据互操作性并解决数据异构性问题。资源描述框架（RDF）模型被用于物联网数据的集成，其中RDF引擎充当语义集成的网关。然而，在动态边缘设备网络中对从分布式来源获取的RDF数据进行存储和查询是一项具有挑战性的任务。边缘的分布式特性与点对点（P2P）系统具有相似之处，包括节点异构性、有限可用性和资源限制等属性。这些节点主要承担数据存储和处理相关的任务。因此，P2P模型为构建分布式RDF存储提供了一种颇具吸引力的方案。本文基于P-Grid（一种用于P2P系统中负载均衡和范围查询处理的数据索引机制），提出了一种在低成本边缘设备P2P网络上存储和共享RDF数据的设计方案。我们的设计旨在将P-Grid与基于边缘的RDF存储解决方案RDF4Led进行集成，以构建一个P2P RDF引擎。该集成能够维持RDF数据访问和查询处理能力，同时随着数据和网络规模的扩大而进行扩展。我们通过在一个包含多达16个树莓派4设备节点的P2P网络上进行实验，展示了实现方案的扩展行为。