A node is a device on a blockchain network, that is in essence the foundation of the technology, allowing it to function and survive. Nodes are distributed across a widespread network and carry out a variety of tasks. In this segment of the Academy we will examine the qualities of a node on a blockchain network.
A node can be any active electronic device, including a computer, phone or even a printer, as long as it is connected to the internet and as such has an IP address. The role of a node is to support the network by maintaining a copy of a blockchain and, in some cases, to process transactions. Nodes are often arranged in the structure of trees, known as binary trees. Each cryptocurrency has its own nodes, maintaining the transaction records of that particular token.
Nodes are the individual parts of the larger data structure that is a blockchain. As the owners of nodes willingly contribute their computing resources to store and validate transactions they have the chance to collect the transaction fees and earn a reward in the underlying cryptocurrency for doing so. This is known as mining or forging.
Processing these transactions can require large amounts of computing and processing power, meaning that the average computer’s capabilities are inadequate. Generally, professional miners tend to invest in extremely powerful computing devices known as CPUs (central processing units) or GPUs (graphics processing units) in order to keep up with the demand for processing power that is required for them to validate transactions and as such earn the rewards that comes with doing so.
The power required for multiple nodes to mine is actually so considerable that electricity costs become a serious factor too. This is the reason why some of the largest and most profitable mines are found in places where electricity is cheaper, such as China or Venezuela.
Root node – The highest node in a binary tree.
Parent node – A node that has other nodes extending from it.
Child node – A node that extends from a different node.
Leaf node – A node with no children.
Sibling nodes – Nodes connected to the same parent node.
Tree – A data structure of nodes starting with a root node.
Forest – A set of trees of nodes.
Degree – The number of children of the node.
Edge – The connection between nodes.
For example : Running a Lisk Blockchain Node
The requirements to own a node vary between cryptocurrencies and their consensus protocols. For example, a Delegated Proof of Stake consensus protocol requires stakeholder approval. Therefore, in order to become an owner of a node that is forging, a user must first become a delegate which requires a certain number of tokens supporting them. In some ecosystem this is done by gaining votes (each vote has a more or less significant influence depending on the number of tokens of the voter).
In practice, this means either buying tokens or receiving votes from other users of the network who are holding tokens. Regardless, the delegate must have enough tokens supporting them to become a node that can validate transactions and earning tokens as a reward.