blockchain technology: Discussing security (51% attack) closeup photo of three round coins in person s palm The Blockchain is a peer-to-peer network consisting of interconnected nodes (users). As a peer-to-peer network, each participating node on the Blockchain is an equipotent participant containing a complete copy of an immutable ledger(block). The blockchain’s block is a data structure used to keep track of transactions performed on the network. Since all nodes must reference all transactions and have equal privileges on the network, transactions are committed based on a consensus algorithm. The integrity and potency of the blockchain network lie in its ability to maintain an unbiased immutable ledger throughout the network. The consensus algorithm designed to manage the creation of a block (committing a transaction) must ensure that no block is illegally added.