Blockchain
Blockchain is a decentralized digital ledger that stores all transactions in a distributed fashion (that is, each node in the network gets a transaction copy). Every transaction in the blockchain (that is, every block) is stored alongside a timestamp that is validated and approved by all the entities or nodes in the network. Once approved, the transaction is aggregated as a block and replicated on each node in the network. As a result, transactions maintained by blockchain technology are considered immutable and tamperproof. These capabilities enable blockchain to solve one challenge – that is, integrity. Here, there are three key security challenges that any IoT solution is expected to mitigate, which form the Confidentiality, Integrity, and Availability (CIA) triad. In Figure 12.1, blockchain is represented using this image:
Figure 12.2 – Blockchain
Benefits of combining IoT and blockchain
As we saw in Chapter 11, field devices...