Bench Talk

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Blockchain is an evolving technology with roots in cryptocurrencies. It provides an immutable digital ledger that is decentralized and secure. But while blockchain is the enabling technology for Bitcoin, it also has various uses in the rapid growth of Internet of Things (IoT) technology. Here, we'll explore blockchain and how it can benefit IoT in terms of security and trust in both data and the management of a massive network of devices.

Blockchain, as the name implies, is a chain of blocks that form a secure, decentralized, distributed digital ledger. The blockchain can be used to record "transactions". Each block includes one or more transactions, a timestamp, and a hash of the prior block in the chain. Blocks are not unique to a single chain, but instead are replicated to multiple chains within other devices in the system. Therefore, instead of a single place of truth within a system, the truth is distributed, making it less prone to single points-of-failure and introduces the ability for consensus, or agreement of truth within the system.

Transparent and immutable, blockchain transactions establish trust within a distributed system. Unlike a traditional transactional system, blockchain is a write-only structure. New transactions can be added to the chain, but not changed or removed without altering all subsequent blocks in the chain.

Blockchain and IoT are interesting partners as both represent distributed systems with no central point of control. Let's explore some key examples of blockchain applied to IoT systems.

Consider a complex piece of equipment that requires periodic maintenance. Typically, when maintenance occurs, paper or electronic records track the activities performed during maintenance, but these records can be modified to show maintenance performed even when it hasn't. Utilizing distributed systems within the equipment, maintenance records can be generated with a periodic sampling of the system’s operation. This provides an immutable and traceable history of the equipment's maintenance interspersed with its own operational data. A leased industrial vehicle could benefit here by providing the owner with detailed tamper-proof information about the vehicle's use and repairs.

Surveillance cameras are another useful example of the application of blockchain. Consider a camera that periodically tracks changes in its field of view. These changes, logged as still images, include their own metadata to identify date and time. But rather than trusting the images and metadata, trust can be guaranteed through the use of blockchain. Images are securely distributed into a blockchain network as transactions, with metadata consisting of the camera location and timestamp. The immutable nature of blockchain makes it more difficult to tamper with images and metadata, and easier to trust when the images represent some form of evidence.

Smart homes can also rely on blockchain to securely store and distribute sensor data while protecting it against abuse through public-key cryptography. The distributed ledger containing encrypted records secures a home's data against abuse.

IoT is not just a future, it's a technology that is here today and growing rapidly. But one of the key challenges for IoT is security and trust in both the data and the management of a massive and decentralized network of devices. Blockchain offers a solution for these IoT challenges.