What is Blockchain?

A blockchain is a shared, publicly accessible database that is shared among numerous computers in a network.

Data and information are kept in units called "blocks," which are grouped together in sequential order. The transaction data must be included in a block in order for Fiero to be sent to a recipient.

The term "chain" describes how each block contains a cryptographic reference to its parent. Blocks are therefore connected together. The data in a block cannot be modified without also changing all blocks that come after it, which would necessitate network-wide consensus.

Every computer in the network must agree to accept both the chain as a whole and each new block. "Nodes" are the titles given to these computers. Nodes ensure that the same data is accessible to everyone using the blockchain. A consensus mechanism is required for blockchains in order to implement this distributed agreement.

In blockchain platforms, consensus mechanisms can be divided into permissionless (Bitcoin, Etherium) and permissioned (Apla, Ethereum Private).

In a permissioned blockchain, all nodes are pre-authenticated. This advantage allows to use of consensus types that provide a high transaction rate in addition to other benefits. One of these consensus types is Proof-of-Authority (POA) consensus.

Proof-of-Authority (POA) is a new consensus algorithms family that provides high performance and fault tolerance. In POA, rights to generate new blocks are awarded to nodes that have proven their authority to do so. To gain this authority and a right to generate new blocks, a node must pass a preliminary authentication.

The network's nodes check and verify new blocks once they are broadcast to them, updating everyone's knowledge of the blockchain's current state.