Aug 2026· Peer-to-Peer Networking and Applications· Vol 19· 0 citations· 38 references
TL;DR
A Cloud-Fog-IoT architecture integrated with a Directed Acyclic Graph (DAG)-based blockchain to enhance scalability and security for secure smart city deployments is proposed.
Abstract
Smart city operations increasingly depend on timely and secure data management, yet Fog-IoT ecosystems face persistent issues related to latency, energy consumption, and data integrity. This study proposes a Cloud-Fog-IoT architecture integrated with a Directed Acyclic Graph (DAG)-based blockchain to enhance scalability and security. Experimental evaluation was conducted using a 10-node peer-to-peer topology (8:2 transaction mix of reads to writes, 1 MB block size, 500 ms block timeout) across Raspberry Pi 4B devices (4GB RAM, gigabit Ethernet). Compared to a cloud-IoT baseline (centralized AWS m5.large, mean network latency 70 ms) and a fog-only configuration (Intel NUC edge nodes, direct aggregation), the proposed system demonstrated a mean transaction throughput of 560 tx/s (95% CI: ), compared with 430 tx/s (95% CI: ) and 350 tx/s (95% CI: ), respectively. Mean end-to-end latency was reduced to 220 ms (95% CI: ), compared to 290 ms and 310 ms for cloud-IoT and fog-only systems. Energy consumption decreased to 0.22 Joules/tx (95% CI: [0.21, 0.23]), versus 0.37 and 0.30 Joules/tx for the baselines. The architecture supported 15 concurrent nodes versus 9 for the cloud-IoT system and achieved a transaction success rate of 99% (cloud-IoT: 90%; fog-only: 91%). Results indicate robust and scalable performance for secure smart city deployments, with consistent definitions and units throughout the manuscript.
The ubiquitous deployment of Internet of Things (IoT) in smart building ecosystems generates massive volumes of multi-dimensional data, rendering secure storage and efficient retrieval paramount challenges. Although blockchain technology ensures data integrity and traceability, applying it to resource-constrained IoT networks exposes a fundamental “storage trilemma” among cost, latency, and scalability. Conventional approaches, relying on either static local retention or full cloud offloading, fail to reconcile these conflicting objectives. In this paper, we propose a Heat-Driven Hybrid Storage (HDHS) architecture that addresses limitations of existing hybrid storage systems-which rely on static parameters and reactive policiesthrough three key innovations: predictive heat modeling, dynamic redundancy adaptation, and multi-objective optimization. Specifically, HDHS incorporates a time-decay model with cost-aware uncertainty estimation to forecast block access “heat” under noisy conditions. Based on these predictions, the system dynamically tunes redundancy rates and utilizes rateless fountain codes to optimize the trade-off between storage footprint and data durability. Furthermore, we design a cloud-window optimizer that addresses a multi-objective trade-off to determine an effective boundary for local-cloud data migration. Extensive experiments on real-world datasets demonstrate that our scheme achieves a 40.7% reduction in storage costs, maintains sub-3ms query latency for 74.7% of queries, and ensures 99% + data reliability in permissioned blockchain environments.
Wei Yang, Xiaohua Wu, Yichang Chen et al.· Annual International Compute...· 0 citations
As IoT deployments rapidly expand, ensuring comprehensive end-to-end security across identity, authorization, communication, integrity, and auditability is critical. This paper presents BISF-IoT, a Blockchain-Integrated Security Framework that utilizes a permissioned ledger as a tamper-evident control plane while keeping high-volume telemetry and raw logs off-chain. BISF-IoT integrates decentralized identity (DID) management, capability-based authorization with explicit revocation under a freshness bound Δ, and secure-channel identity binding for MQTT/CoAP edge devices. Formal game-based proofs establish five core security properties: DID authenticity, authorization soundness, revocation safety, tamper-evident logging, and auditable anomaly alert non-repudiation. Performance evaluation through simulation with up to 10,000 devices demonstrates near-linear scalability, processing up to 160,000 transactions per day with a scaling efficiency of ~0.90–1.00. Authorization latency increases moderately from 120 ms at 100 devices to 650 ms at 10,000 devices. Therefore, it remains within practical operational limits. Blockchain storage grows steadily at approximately 37–42 MB/day by storing compact Merkle commitments and security artifacts while avoiding raw data bloat. Meanwhile Log verification time exhibits sub-linear growth, with verification cost per entry decreasing from 0.200 ms to 0.055 ms as log size increases from 100 to 10,000 entries, reflecting efficient Merkle inclusion proof mechanisms. These results confirm BISF-IoT’s capability to provide scalable, secure, and verifiable control-plane operations suitable for large-scale IoT environments.
Shahid Imran, Kalsoom Safdar, Muhammad Usman Younus· International Journal of Inn...· 0 citations
Smart cities increasingly depend on large-scale Internet of Things (IoT) infrastructures for traffic management, smart grids, and environmental monitoring. Ensuring data integrity, transparency, and privacy in such systems remains a major challenge because centralized platforms are vulnerable to manipulation, while conventional blockchain-based solutions suffer from scalability and confidentiality limitations. This study proposes TrustIoT-Chain, a privacy-preserving blockchain framework that integrates off-chain digital twins, cryptographic data commitments, zero-knowledge compliance verification, and a sharded blockchain architecture for scalable smart city monitoring. The objective of this work is to provide real-time verifiable IoT monitoring with strong privacy guarantees and high system throughput. Large-scale simulations with one million synthetic IoT events demonstrate that the proposed framework achieves up to 24,910 events/s throughput with an average verification latency of 410 ms using 16 shards. Energy consumption is reduced by approximately 45% compared with non-sharded blockchain systems with zeroknowledge proofs, while privacy leakage measured by mutual information decreases to 0.05 bits. The key novelty lies in the joint integration of the digital twins with the blockchain-based zero-knowledge auditing, and sharding for the smart city IoT systems. This approach enables transparent regulatory compliance verification without exposing the raw sensor data, offering the scalable, and privacy-aware foundation for the future smart city governance, and trusted IoT ecosystems.
Shrutika Khobragade, J. Bakal· 2026 7th International Confe...· 0 citations
The Energy-Aware Hierarchical Green Fog framework is presented, which introduces a unified reinforcement learning (RL) orchestration layer that explicitly incorporates residual energy, renewable energy availability, spatial proximity, and task deadlines into hierarchical fog-cloud decision-making.
M. Harandi, Afshin Yaghoobi· Scientific Reports· 0 citations
Preserving the quality and safety of perishable products requires continuous monitoring and reliable traceability. Although the Internet of Things (IoT) enables real‐time data collection, multi‐organizational supply chains lack a common mechanism for assigning data custody while maintaining transparency, integrity, and performance.
This study proposes and evaluates an architecture integrating IoT, edge/fog computing, and hybrid storage—an off‐chain traditional database combined with a permissioned blockchain—to monitor and trace perishable products.
A prototype was implemented using IoT devices and simulators, edge and fog components, and hybrid storage. High‐volume sensor data and critical records were stored off‐chain in MongoDB, while their corresponding hashes were stored on‐chain using Hyperledger Fabric. Four controlled experiments assessed insertion response time, the impact of increasing sensors and edge devices, blockchain queue performance under burst workloads, and blockchain storage consumption. The hybrid approach was compared with MongoDB‐only and Hyperledger Fabric‐only storage.
Hybrid storage achieved insertion up to six times faster than blockchain‐only storage. Response times increased with simultaneous requests and additional edge devices, while asynchronous ordered insertion prevented transaction conflicts during bursts. The prototype achieved 18.5 transactions per second, below the 65 estimated for an illustrative supply‐chain scenario. Blockchain storage grew approximately 8 MB per 100 records, reaching about 1 GB for 12,800 hashes.
The prototype demonstrates the feasibility of combining off‐chain storage, permissioned blockchain records, and edge/fog processing to provide verifiable traceability while reducing on‐chain load. Larger‐scale, real‐world evaluations and storage‐management strategies remain necessary.
R. Hoffmann, C. Moratelli, A. R. Pinto· Software, Practice & Experie...· 0 citations
BELS-IoT is proposed, a novel decentralized protection architecture that integrates a cryptocurrency-based blockchain layer with a multi-layer ensemble learning engine that rewards honest behavior and penalizes malicious activities while maintaining privacy through federated learning with blockchain-verified reputation scores.
Anwar Kalghoum, Leila Azouz Saidane· SN Computer Science· 0 citations