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Blockchain for IoT Security and Privacy

Posted by: jur023

April 20, 2017

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. This project, which is a collaboration between Data61 and UNSW, is designing a lightweight BC-based 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 smart home, to automotive and smart grids.

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

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.