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Cited by 388Blockchain Technology Applications and SecurityIoT and Edge/Fog ComputingInternet of Things and AI

The DOI matches its Crossref record; 290 of the 292 references it cites were found in a registry or an index; none of the 190 sources its claims cite is checked for support yet.

A survey on the adoption of blockchain in IoT: challenges and solutions

Open access
Uddin, Md Ashraf, Stranieri, Andrew, Gondal, Iqbal, Balasubramanian, Venki·2021·Blockchain: Research and Applications
DOI 10.1016/j.bcra.2021.100006
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Abstract

Conventional Internet of Things (IoT) ecosystems involve data streaming from sensors, through Fog devices to a centralized Cloud server. Issues that arise include privacy concerns due to third party management of Cloud servers, single points of failure, a bottleneck in data flows and difficulties in regularly updating firmware for millions of smart devices from a point of security and maintenance perspective. Blockchain technologies avoid trusted third parties and safeguard against a single point of failure and other issues. This has inspired researchers to investigate blockchain’s adoption into IoT ecosystem. In this paper, recent state-of-the-arts advances in blockchain for IoT, blockchain for Cloud IoT and blockchain for Fog IoT in the context of eHealth, smart cities, intelligent transport and other applications are analyzed. Obstacles, research gaps and potential solutions are also presented.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

This survey reviews blockchain adoption in IoT, Cloud of Things, Fog of Things, and SDN across eHealth, smart cities/home, intelligent transport, and other applications, cataloguing challenges and potential solutions. It finds blockchain can address privacy, single-point-of-failure, bottleneck, and trust issues, but resource, throughput, storage, privacy-transparency, and regulatory obstacles remain.

Key findings

  • The survey identifies six main adoption challenges: power/performance/security trade-off, data concurrency and throughput, IoT connectivity, big-data storage, transparency vs privacy, and regulation. It cites that a blockchain node would need approximately 730 GB/year if 1000 participants exchange one 2 MB image per day, and notes anticipation of more than 50 billion connected devices by 2020.
  • It reviews consensus mechanisms and blockchain types, noting Bitcoin’s 12.5 bitcoins per block at one block per 10 min, PoW energy consumption compared with Ireland, Austria, and Colombia, and that Ethereum business process execution can cost two orders of magnitude more than Amazon SWF.
  • Proposed solutions include smart agents/gateways, sharding, sidechains, off-chain storage, homomorphic encryption, proxy re-encryption, federated learning, and regulation combining law, social norms, and economic means.
  • Application review covers eHealth, smart cities/home, vehicular networks, and miscellaneous IoT; blockchain roles include access control, data sharing, authentication, trust, payment, and supply chain. Many reviewed works are conceptual or lack performance/security evaluation; the majority of included studies were published in 2019, with the largest share from IEEE Xplore.

Methods

  • Design: narrative survey/review of recent state-of-the-art advances in blockchain for IoT, Cloud IoT, Fog IoT, and SDN, covering eHealth, smart cities, intelligent transport, and other applications.
  • Data: literature searched with keywords including blockchain and IoT, healthcare, Fog, Cloud, and Agent; downloaded from IEEE Xplore, ScienceDirect, Elsevier, ACM, Springer, MDPI, and SAGE. Statistics show the largest percentage from IEEE Xplore, second-highest from Elsevier journals, and the majority published in 2019.
  • Analysis: reviewed studies against attributes including blockchain type, consensus mechanism, access control, scalability, on-chain/off-chain storage, tools/simulators, contributions/outcomes, and limitations/remarks; challenges and solutions are synthesized in tables and figures.

Limitations

  • The paper does not state its own limitations explicitly. It states that current blockchain platforms have scalability limitations, high computational cost, security/privacy issues, and regulatory challenges, and it repeatedly notes that many reviewed blockchain-IoT proposals are conceptual, not implemented, or lack performance/security evaluation.
  • Evident from the text: the survey is narrative rather than a systematic review with a formal search/selection protocol; it relies on selected databases and keyword searches, and its statistics are descriptive (publisher/year/application counts) without meta-analysis.
  • Evident from the text: coverage is broad but uneven; some sections and tables are incomplete or rely on author-reported weaknesses, and the survey does not independently validate the reviewed systems.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1016/j.bcra.2021.100006

Cites

290 of 290 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

0 of 190 cited sources checked · 0 supported · 0 flagged

Show all 93 claims

  • Probably not a substantial claim. 271
  • It may state two separate claims as one. 119
  • The quote only partly states this claim. 1
318 of 318

  • The paper relies on this without support.

    PoW prevents malicious, Sybil attacks and makes the blocks tamper-proof.

    “On the contrary, PoW prevents malicious, Sybil attacks and makes the blocks tamper-proof.”

  • The paper relies on this without support.

    The blockchain throughput is limited thanks to its complex cryptographic security protocol and consensus mechanisms.

    “The blockchain throughput is limited thanks to its complex cryptographic security protocol and consensus mechanisms.”

  • The paper relies on this without support.

    The IoT has limited capabilities to connect them with blockchain technology in order to provide novel business opportunities for the implementation of new applications and services in various domains.

    “The IoT has limited capabilities to connect them with blockchain technology in order to provide novel business opportunities for the implementation of new applications and services in various domains.”

  • The paper relies on this without support.

    Blockchain can guarantee transparency of transactions, which is essential in some applications like finance.

    “Blockchain can guarantee transparency of transactions, which is essential in some applications like finance.”

  • The paper relies on this without support.

    Due to the absence of governance, records cannot be filtered for maintaining privacy before publishing them on the blockchain.

    “In addition, due to the absence of governance, records cannot be filtered for maintaining privacy before publishing them on the blockchain.”

  • The paper relies on this without support.

    Actions resulting from executing code such as smart contracts on a DTL can breach law.

    “Actions resulting from executing code such as smart contracts on a DTL can breach law.”

  • The paper relies on this without support.

    Due to the anonymity of the DTL, it is not so straightforward to distinguish the parties carrying out transactions for illegal services.

    “Due to the anonymity of the DTL, it is not so straightforward to distinguish the parties carrying out transactions for illegal services.”

  • The paper relies on this without support.

    Research has shown that by using disruptive technologies such as blockchain, these issues can be minimized.

    “Research has shown that by using disruptive technologies such as blockchain, these issues can be minimized.”

  • The paper relies on this without support.

    The high computational power required to run blockchain algorithms has slowed down the advancement of these technology-based applications on resource constrained devices.

    “The high computational power required to run blockchain algorithms has slowed down the advancement of these technologybased applications on resource constrained devices.”

  • The paper relies on this without support.

    Difficulties in regularly updating firmware for millions of smart devices from a point of security and maintenance perspective.

    “difficulties in regularly updating firmware for millions of smart devices from a point of security and maintenance perspective.”

  • The paper relies on this without support.

    The distributed ledger in blockchain is tamper-resistant and removes the need to trust participating parties.

    “The distributed ledger in the blockchain is a tamper-resistant, which removes the need to trust the participating parties.”

  • The paper relies on this without support.

    Cloud computing has virtually unlimited storage and computational resources.

    “Meanwhile, Cloud computing has virtually unlimited storage and computational resources that can deliver on-demand, reliable, and secure IoT services.”

  • The paper relies on this without support.

    Not all blockchain consensus mechanisms are suitable in a Fog ecosystem due to their limited resources.

    “Further, Not all blockchain consensus mechanisms are suitable in a Fog ecosystem due to their limited resources.”

  • The paper relies on this without support.

    Only a few countries, including Estonia and Peru, have already adopted blockchain health management in practice.

    “However, only a few countries, including Estonia, Peru, have already adopted blockchain health management in practice.”

  • The paper relies on this without support.

    Data interception can occur when IoT devices transfer data between them, questioning the reliability of the collected data.

    “Further, the data interception can occur when IoT devices transfer data between them which questions the reliability of the collected data.”

  • The paper relies on this without support.

    IoT devices have no accurate information available about the agents in a new environment.

    “However, IoT devices have no accurate information available about the agents in a new environment.”

  • The paper relies on this without support.

    IoT devices are often unknown and not referenced, and the traditional approach of asking other trusted agents for information is usually impracticable.

    “Further, IoT devices are often unknown and not referenced, and the traditional approach of asking other trusted agents for information is usually impracticable.”

  • The paper relies on this without support.

    The IoT devices in a smart home are usually connected to global internet and consumers via Gateway services.

    “The IoT devices in a smart home are usually connected to global internet and consumers via Gateway services.”

  • The paper relies on this without support.

    Patient monitoring systems continuously stream health data and transactions are more frequently created in such applications.

    “Patient monitoring system continuously streams health data and transactions are more frequently created in such applications.”

  • The paper relies on this without support.

    No legislation is still enacted for governing the existing blockchain applications.

    “No legislation is still enacted for governing the existing blockchain applications.”
20 of 20

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • On-chain storage cost is described as both high and low

    Minor

    The same section first says inserting a block on-chain has a high cost, then says the on-chain storage method has a low cost because a hash is small. The latter appears to describe the off-chain method introduced between these statements.

  • BCPay blockchain type is both specified and said to be unspecified

    Minor

    Table 17 assigns Zhang et al. [212] the blockchain type EEB and lists Ethereum as its tool, but the accompanying assessment says the kind of blockchain used was not highlighted.

  • Conflicting claims about resistance to DDoS attacks

    Minor

    The security discussion says blockchain can withstand DDoS attacks but later calls it susceptible to DDoS attacks, without distinguishing the circumstances.

3 of 3

Citations

Cites

Items 201–290 of 290

Flagged first, then by citations

2 of the 292 references couldn’t be matched to a known paper.

Research works printed but not linked: 3

  1. Elia, 2015, The rabin cryptosystem revisited. Applicable Algebra in engineering, Communication and Computing, 26, 251
  2. Nasir, 2018, vol. 2018, 3976093
  3. Wood, 2014, 151, 1

Cited by

Sorted by citations

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Related

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Metadata

Authors
Uddin, M. A., Stranieri, A., Gondal, I., & Balasubramanian, V.
Affiliations
Federation University (AU)
Corresponding author
Uddin, Md Ashraf
ORCID
Venue
Blockchain: Research and Applications
Publisher
Elsevier BV
Published
2021-06
Volume
2
Issue
2
Pages
100006
ISSN
2096-7209 (ISSN-L)
DOI
10.1016/j.bcra.2021.100006
OpenAlex
W3133065136
Semantic Scholar
a1cdb81de39f32a8a0f51b33a84c13bbf0f18a4a
Cited by
365
References
292
Citations by year
2026: 14 · 2025: 69 · 2024: 78 · 2023: 106 · 2022: 75 · 2021: 23
FWCI
63.74
Type
journal article
Language
en
Open access
Licence
Locations
  • Blockchain Research and Applications (publishedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • Figshare (submittedVersion, cc-by)
Topics
  • Physical Sciences › Computer Science › Information Systems › Blockchain Technology Applications and Security
  • Physical Sciences › Computer Science › Computer Networks and Communications › IoT and Edge/Fog Computing
  • Physical Sciences › Computer Science › Information Systems › Internet of Things and AI
Keywords
blockchain, Internet of Things, blockchain adoption, fog computing, cloud IoT, Internet of Things security, privacy, single point of failure, firmware updates, e-health, smart cities, decentralized systems

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