How to Secure the Internet of Things (IoT) with Blockchain

Both the Internet of Things (Iot) and Blockchain technology are set to revolutionize the world we live in. These two equally exciting technologies are still in their infancy – so far as exploiting their true potential is concerned – but already industry experts are excitedly debating all the different ways that our lives that will benefit when they fully implemented.

As our lives become increasingly reliant on smart devices, Internet of Things use is set to grow enormously. A recent article by Forbes predicted that “Internet of Things Market to Reach $267B by 2020”. This huge growth rate gives an idea just how much businesses as well as us, the general public, are going to rely on IoT before the decade is out.

Blockchain is set to make an equally big splash in years to come. Despite being used as the basis for the well-known cryptocurrency, bitcoin, which was created back in 2009, it is only relatively recently that the tech industry has really rushed to throw its full weight behind developing the technology.

This rush was undoubtedly the result of cryptocurrency mania which was ignited by the massive rise in the value of bitcoin back in 2017. The blockchain boom is no cryptocurrency gold rush however, most insiders agree that there is enormous potential for improving existing systems by enabling some level of blockchain integration.

With our increasing reliance on technologies such as IoT, numerous issues arise relating to the use, privacy, and safety of our data, all of which must be addressed as we increasingly rely on IoT networks in years to come.  In this article, I aim to outline how improving IoT security with blockchain will yield enormous benefits that will help companies in the future maintain trust by preventing costly data breaches etc.

I will begin by giving a brief explanation as to what these two technologies are all about and outlining what the advantages are to using blockchain. I will then look at how to secure the internet of things with blockchain by highlighting examples of where blockchain for IoT security could be employed to improve on existing IoT only solutions.


Internet of Things (IoT)
How to secure IoT with blockchain: The problem of centralization
Secure IoT devices using blockchain
Create a trustworthy IoT environment
Prevent Physical Theft
My Final Thoughts

Internet of Things (IoT)


The Internet of Things (IoT) allows for the creation of networks of sophisticated smart devices such as phones, smart cars, and smart home appliances. The potential benefits of such networks are too many to list here, but examples include everything from allowing homes to learn their occupant’s behavior patterns so that they can increasingly automate chores such as reordering food etc., to allowing smart cars to be ready and waiting outside your door to drive to you to work in the morning.

Granted, these examples might be a little way off, but already a huge range of smart devices are available to consumers. There are roughly 9 billion smart devices of one type or another online today. This figure is set to rise to around 30 billion by 2020, which will equate to almost 3 smart devices per person in the world.

A key component of IoT is data. In order to operate, an IoT network must send and receive large amounts of sensitive data. One such example is the security access data that is required for the August Smart Lock. This smart lock allows homeowners to unlock their home just by using their phone, without the need for a key.

Naturally, homeowners need to be assured that no unauthorized person is going to be able to steal entry code data and gain access to their home. This means that the IoT network must be secure at all times. Not only that, data is often transferred between devices that have different administrators and data usage policies, thereby creating a challenging management environment that also requires close attention to data security.

According to an article published in eSecurity Planet, 48 Percent of U.S. Companies Using IoT Have Suffered Security Breaches. This is a staggering figure, particularly when we consider that this includes some of the biggest and most secure company networks in the world. The figure emphasizes the need for a new approach to data security.



Blockchain has the potential to dramatically increase both the security and level of automation of certain data transactions. The technology allows for the creation of individual blocks of data in a form of a chain. As each new block is added to the last, it forms what is, in essence, a digital ledger containing all the information ever added to the blockchain.

Since the data on each new block is partly calculated from information held on the previous block in the blockchain, in order to alter a block, an unauthorized individual would have to change the information on all the blocks linked to it to prevent the change from being immediately noticed. In the case of a cryptocurrency blockchain, for example, this may well mean having to change every single block on the chain.

The really exciting thing about blockchain technology is that it operates as a peer-to-peer decentralized network. As such a network, blockchains don’t require any controlling party to function. This has enormous implications for many of the business processes we all rely on today.

More than any other example, bitcoin and has shown that it is possible to create blockchain-based solutions that allow us to circumnavigate powerful institutions, which until now have had a monopoly on these processes.

Another key factor in this decentralized approach is that all the peers or ‘nodes’ involved in the network must agree on whatever changes are to be made. So should a hacker or other unauthorized party attempt to make a change to the digital ledger without permission, the other nodes will resist this change and prevent the data from being altered.

The only way it would be possible for someone to alter the blockchain would be to gain control over the majority of the nodes on the network at the same time in order to successfully complete the change. When contemplating how difficult this would be just keep in mind that each node has its own unique access key code also.

Just to give you an idea of the enormity of the task, as of May 2016, Ethereum’s network had 25,000 active nodes meaning that any attempt to alter data in this way would be next to impossible.

Key Characteristics of Blockchain:

  • Decentralized – No controlling power or point of failure.
  • Immutable – Ledgers can’t be altered without the network agreeing to it.
  • Facilitates trustless transactions – Unalterable ledger means transactions can be made to unknown parties with the minimum of risk.
  • Distributed processing power – Decentralized nature means the network shares the load.

Advantages of Blockchain:

  • Increased trust
  • Removes the need for a controlling power
  • Better security
  • Complete records of all transactions


How to secure IoT with blockchain: The problem of centralization


Secure IoT devices using blockchain

IoT operates a distributed client/server model that requires an administrator to manage the network. This centralized authority is the weak point when it comes to IoT cyber-security. To operate normally, IoT devices rely on this authority to determine how they behave.

If there is a breach of security at the central authority then the information being sent by the smart devices is largely at the mercy of the hackers. This makes attacking the central authority very appealing to cyber hackers as large amounts of data can be collected in one go.  A series of cyber-attacks occurred in 2017, many of which exploited this weakness and allowed hackers to make off with sensitive data relating to 100’s of millions of American citizens.

Since the decentralized nature of blockchain technology would negate any central attack, hackers would have to target individual nodes on the network in order to try to obtain the data they want. In a blockchain network, smart devices are able to actively participate in validating transactions.

This means that the network would be able to guard against any hack by validating predetermined ‘acceptable’ behavior for any irregularities. Once a device on the network was identified as not behaving correctly, it could be isolated to prevent it being used to access further sensitive data or being used to unlock a person’s home etc.

Create a trustworthy IoT environment

Blockchain ledgers require users to enter a unique key code in order to access the network. This means that all the interactions/transactions have accountability built in.

Any changes made have to be signed and therefore can be traced back to whoever made them. Any unauthorized changes will be prevented by the network as none of the other nodes attached to the network will accept the change.

So when it comes to the supply chain industry, for example, smart devices could be used to track items for the entire length of the supply chain. Since items would be signed for at each step of the chain, tracking their progress could be done in real-time too. Any missing or delayed deliveries could be tracked in seconds. This would improve both the efficiency and reliability of any supply chain blockchain technology was applied to.

One such company to realize the enormous value of intergrating blockchain into its supply chain management is Taiwanese company OwlTing. You can read more about their project to use blockchain technology to increase food safety here.

In the public domain, such a blockchain based IoT system could, for example, be used in schools or universities to ensure pupils were in class at the appropriate times and even making sure they were doing their homework too. Since the parents could also be included on the school blockchain, they would also be able to view their children’s progress via an authorized smart app.

The ability of teachers to leave feedback and report any wrongdoings would empower parents by allowing them to motivate/reward their children on a real-time basis. This kind of system could also finally signal the end of those dreary parent evenings that students, parents, and teachers alike all hate going to.

Prevent Physical Theft


Using blockchain to secure IoT deployments in this way would also help to tackle the physical theft of smart devices. A smart device that is either reported to the IoT blockchain network as being stolen or identified by the network as behaving according to a set of criteria that correlates as having been stolen, could immediately be quarantined by the network and have its important data forwarded to the police and owners etc.

Information such as the smart devices’ current location and even secret pictures taken of the operator could be automatically sent to the nearest police officers without any need for 3rd party intervention.

The devices’ unique manufacturing number could also be shared with such organizations as the OS provider and other application platforms automatically, which would enable them to blacklist the device. This would make the current problem of thieves simply performing a factory reset and using the device for themselves a thing of the past.

My Final Thoughts

The application of blockchain into IoT networks is one of the most exciting long-term uses of this great new technology. Individuals, as well as businesses all around the globe, stand to benefit from more secure IoT networks. It will help secure all aspects of IoT use and allow everyone to feel more trust that their data is safe.

The enhanced security environment that blockchain facilitates will massively help to overcome people apprehensions when it comes to using an increasing number of smart devices in their daily lives.

Knowing that using a smart lock for your home is safer than using a physical key, for example, will greatly speed up the transition we all make to using such smart technology.

In the same way that self-driving cars promise to make driving part of what we now call’leisure time’, smart devices using blockchain technology will help automate many more aspects of our daily chores, leaving us all with more time to sit back and enjoy life.

Aran Davies

Aran Davies

Blockchain Expert | Developer | Writer | Photographer
Aran Davies