Basics of blockchain for the IoT

With the rise of Bitcoin, corporate interest in the underlying blockchain technology has risen dramatically. Confusion arises, however, because much of the discussion centers on cryptocurrency, which is only one approach to using blockchain. To determine an approach that makes sense for the IoT, developers must first strip blockchain to its basics and build from there.Blockchain technology, essentially, provides a mechanism for a network of nodes to securely exchange information (called transactions) and mutually create a shared ledger documenting those transactions in a record that resists alteration. The basic process is simple, as shown in  below. A node securely informs all the others of a transaction, which they validate and add to their list of pending transactions. At some point a "publishing node" creates a data block containing none, some, or all the pending transactions, which it presents to the network. When the nodes reach a consensus that the proposed block is valid they add it to their copy of the shared ledger and remove the corresponding transactions from their pending list.