The Internet of Things (IoT) is the network of physical objects such as smart appliances , smart security systems, smart locks, and smart doorbells etc. that are embedded with software, sensors and other technologies in order to connect and exchange data with other devices and systems over the internet.
A blockchain is a digital ledger of transactions that is photocopied and distributed across the entire network of computer systems on the blockchain. Blockchain is a system of storing information in a way that makes it difficult or impossible to change, hack, or cheat the system. Based on a peer-to-peer (P2P) topology, blockchain is a distributed ledger technology (DLT) that permits data to be stored globally on thousands of servers – while letting anyone on the network see everyone else’s entries in near real-time. That makes it difficult for one user to gain control of the network. Since data is encrypted and decentralized, requiring approval from most of the network, data is extremely hard to alter.
Since Blockchain removes control of the data from any single authority, it is the perfect solution for IoT networks. As IoT networks are for individual networks of devices, the decentralized nature of blockchain gives the user complete control over their data.
The Blockchain technology permits for the creation of individual blocks of data in the form of a chain. Each time a block is completed it becomes part of the previous block and gives way to a new block in the blockchain. The completed block is a permanent record of transactions in the past and the new transactions are recorded in the current one. This way, the whole system works in a cycle and data gets permanently stored. To be attached to the blockchain, each block must hold the answer to a complex mathematical problem created using a cryptographic hash function which is irreversible. The node that solves the mathematical problem acquires the right to place the next block on the chain and broadcast it to the network. As the data on each new block is partly calculated from details held on the previous block in the blockchain, in order to change a block, an unauthorized person would have to change the information on all the blocks connected to it to prevent the change from being instantly observed. If a hacker tries to alter the digital ledger, the other nodes will resist this change and prevent the data from being altered.
If an unauthorized person succeeds to gain control over the majority of the nodes on the network, it would be possible to alter the blockchain. Since each node has its own unique access key code, it is very difficult to get control over all nodes.
Most current IoT architectures use cloud computing which is centralized. This centralized authority is the weak point when it comes to IoT cybersecurity. To operate normally, IoT devices rely on this authority to determine how they behave. If there is a violation of security at the central authority then the information being sent by the smart devices is largely at the power of hackers. Since IoT data traffic is not encrypted, hackers can easily steal or destroy the target network data and can bring servers down.
We can secure IoT devices using blockchain. Since the decentralized nature of blockchain technology would nullify any central attack, hackers would have to pick out individual nodes on the network in order to try to obtain the data they want. Smart devices can actively participate in validating transactions through blockchain. Hence blockchain networks would be able to protect against any hack by validating fixed acceptable behavior for any irregularities.
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 recognized as not acting correctly, it could be secluded to prevent it from being used to attack further sensitive data or being used to unlock a person‘s house, lockers etc.