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Blockchain for IoT Security and Privacy

Posted by: jur023

April 20, 2017

With the growing scale and prevalence of Internet of Things sensors in our daily lives, trusting these sensors and systems to deliver reliable data while maintaining our security and privacy is a critical consideration. The IoT network architecture requires decentralised and lightweight approaches for delivering trust, while most conventional approaches are either centralised or computationally demanding.

There has been increasing interest in adopting BlockChain (BC), that underpins the crypto-currency Bitcoin, in Internet of Things (IoT) for security and privacy. However, BCs are computationally expensive and involve high bandwidth overhead and delays, which are not suitable for most IoT devices.

Lightweight Scalable Blockchain

This project, which is a collaboration between Data61 and UNSW, has designed a lightweight scale blockchain (LSB) architecture for IoT that virtually eliminates the overheads of classic BC, while maintaining most of its security and privacy benefits. IoT devices benefit from a private immutable ledger, that acts similar to BC but is managed centrally, to optimize energy consumption. High resource devices create an overlay network to implement a publicly accessible distributed BC that ensures end-to-end security and privacy. The proposed architecture uses distributed trust to reduce the block validation processing time.

Our approach has the following features

  • Eliminates the Proof-of-Work overhead: significantly reduces processing overhead at miners
  • Separate data and transactions flow: decreases service delay while maintaining security and privacy
  • Distributed trust between overlay nodes: gradually reduces the proportion of transactions that require distributed verification as nodes increase their trust
  • Two tiers of BlockChain: a centralised private immutable ledger at local networks to manage local transactions, and a public distributed blockchain at the overlay network.

The table below compares our design to the classic bitcoin blockchain:

Feature Bitcoin BlockChain Immutable Ledger Public BlockChain
Mining requirement POW None None
Forking Not allowed Allowed Allowed
Double spending Not acceptable Not applicable Not applicable
Encryption Asymmetric Symmetric Asymmetric
BlockChain visibility Public Private Public
Transaction dissemination Broadcast Unicast Unicast/Multicast
Distributed Verification All None Some

The figure below illustrates the local network design in a smart home scenario:


while the transaction flow is shown in the figure below


This design is being explored for various sectors, from supply chains and smart homes, to automotive and smart grids.

ProductChain: Scalable Blockchain Framework to Support Provenance in Supply Chains

An increased incidence of food mislabeling and handling in recent years has led to consumers demanding transparency in how food items are produced and handled. The current traceability solutions suffer from issues such as scattering of information across multiple silos and susceptibility in record- ing erroneous data and thus are often unable to produce reliable farm to fork stories of products. Blockchain (BC) is a promising technology that could play an important role in providing data transparency and integrity due to its salient features which include decentralization, immutability and auditability. In this work, we propose a permissioned blockchain framework which is governed by a consortium of key Food Supply Chain (FSC) entities including government and regulatory bodies to promote food provenance. We propose to use a sharded, three-tiered architecture which ensures availability of data to consumers, limits access to competitive partners and provides scalability for handling transaction load. We also propose a transaction vocabulary and access rights to manage read and write privileges to BC supported by the consortium. The framework ensures that trade flows are kept confidential when provenance information is retrieved by consumers and stakeholders.

BlockChain: A Distributed Solution to Automotive Security, Privacy and Liability Assignment

Interconnected smart vehicles offer a range of sophisticated services that benefit the vehicle owners, transport authorities, car manufacturers, and other service providers. This potentially exposes smart vehicles to a range of security and privacy threats such as location tracking or remote hijacking of the vehicle. We show that blockchain (BC), a disruptive technology that has found many applications from cryptocurrencies to smart contracts, is a potential solution to these challenges. We propose a BC-based architecture to protect the privacy of users and to increase the security of the vehicular ecosystem. Wireless remote software updates and other emerging services such as dynamic vehicle insurance fees are used to illustrate the efficacy of the proposed security architecture. We also qualitatively argue the resilience of the architecture against common security attacks.

A key application of blockchain in the automotive sector is for liability assignment, particular for partially or fully autonomous vehicles. We propose a partitioned BlockChain based Framework for Auto-insurance Claims and Adjudication (B-FICA) for CAVs that tracks both sensor data and entity in- teractions with two-sided verification. B-FICA uses permissioned BC with two partitions to share information on a need to know basis. It also uses multi-signed transactions for proof of execution of instructions, for reliability and auditability and also uses a dynamic lightweight consensus and validation protocol to prevent evidence alteration.


Protecting the Right to be Forgotten in the age of Blockchain

Blockchain is an immutable distributed database. It supports traceability and audibility of large scale systems, including IoT. This immutability may be at odds with new legislation, such as the EU General Data Protection Regulation (GDPR) which supports the right to be forgotten by removing data from third party records once it has served its purpose. We propose a Memory Optimized and Flexi- ble BC (MOF-BC) that enables the IoT users and service providers to remove or summarize their transactions and age their data and to exercise the ”right to be forgotten”. To increase privacy, a user may employ multiple keys for different transactions. To allow for the removal of stored transactions, all keys would need to be stored which complicates key management and storage. MOF-BC introduces the notion of a Generator Verifier (GV) which is a signed hash of a Generator Verifier Secret (GVS). The GV changes for each transaction to provide privacy yet is signed by a unique key, thus minimizing the information that needs to be stored. A flexible transaction fee model and a reward mechanism is proposed to incentivize users to participate in optimizing memory consump- tion.

Media Coverage

Forbes: How Blockchain Could Revolutionise the Internet of Things

CMO:How cryptocurrency is set to change the customer loyalty program model

Altoros: Automotive Blockchain: from Manufacturing to Security to Insurance

The Conversation: Who’s to blame when driverless cars have an accident?, republished by the Australian Broadcasting Corporation and the New Zealand Herald.

TripleM National Radio Interview, March 20, 2018

2UE National Radio Interview, March 21, 2018

Computer World: Who is liable when a driverless vehicle crashes? The answer’s on the blockchain

Radio Adelaide interview, April 9, 2018

China Law Insight: Blockchain: An Achilles Boot for Self-driving Cars? How to empower a Smart Home owner with a novel Blockchain architecture?



Raja Jurdak 

Salil Kanhere 

Ali Dorri

Sidra Malik 

Marco Steger

Chuka Oham

Volkan Dedeoglu

Pooja Gupta

Sanjay Jha


Blockchain for Cyberphysical Systems, Salil Kanhere, IFIP Networking Keynote Speech, 2018.

Related Publications

P. Gupta, S.S. Kanhere, R. Jurdak, A Decentralized IoT Data Marketplace, To appear in proceedings of the 3rd Symposium on Distributed Ledger Technology, Gold Coast, Australia, November 2018.

A. Dorri, S.S. Kanhere, R. Jurdak, A Memory Optimized and Flexible BlockChain for Large Scale Networks, Accepted at Future Generation Computer Systems, October, 2018. (in press)

S. Malik, S. Kanhere, R. Jurdak, “ProductChain: Scalable Blockchain Framework to Support Provenance in Supply Chains,” To appear in proceedings of IEEE International Symposium on Network Computing and Applications (NCA), Cambridge, USA, November, 2018.

R.A. Michelin, A. Dorri, R. C. Lunardi, M. Steger, S.l S. Kanhere, R. Jurdak, A. F. Zorzo, “SpeedyChain: A framework for decoupling data from blockchain for smart cities”, To appear in proceeding of the 15th EAI International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services (MobiQuitous), New York, USA, November, 2018.

A. Dorri, S. Kanhere, R. Jurdak, P. Gauravaram, “Toward a distributed, private, and secure IoT using Blockchain,” IM+io Magazine pages: 86-89, June 2018.

C. Oham, R. Jurdak, S. Kanhere, A. Dorri, S. Jha, “B-FICA: BlockChain based Framework for auto-Insurance Claim and Adjudication,” To appear in proceedings of The IEEE International Conference on Blockchain (Blockchain 2018), Halifax, Canada, July, 2018.

A. Dorri, S. Kanhere, R. Jurdak, “Multi-Agent Systems: A  survey,”  IEEE Access, May 2018  DOI: 10.1109/ACCESS.2018.2831228

A. Dorri, M. Steger, S. Kanhere, and R. Jurdak, “BlockChain: A Distributed Solution to Automotive Security and Privacy”, IEEE Communications Magazine, Volume 55, Issue 12, pages 119-125, December, 2017. DOI: 10.1109/MCOM.2017.1700879.

M. Steger, A. Dorri, S. Kanhere, K. Romer, R. Jurdak, and M. Karner, “BlockChains securing Wireless Automotive Software Updates – A proof of concept,” Lecture Notes in Mobility, covering the proceedings of the 21st International Forum on Advanced Microsystems for Automotive Applications (AMAA 2017), Berlin Germany, pages 137-149, August 2017. Paper

A. Dorri, S. Kanhere, and R. Jurdak, “Towards an Optimized BlockChain for IoT,” In proceedings of the 2nd IEEE International Conference on Internet-of-Things Design and Implementation (IoTDI 2017), as part of CPSWeek, Pittsburgh, USA, April, 2017. PDF

A. Dorri, S. Kanhere, R. Jurdak., and P. Gauravaram, “Blockchain for IoT Security and Privacy: The Case Study of a Smart Home,” In proceedings of the 2nd IEEE Workshop on security, privacy, and trust in the Internet of things (PERCOM), Hawaii, USA, March, 2017.