What is a Node?
A network node is a computer or device that is connected to a blockchain network, helping to maintain the distributed ledger. Nodes store a copy of the entire blockchain transaction history and help validate new transactions, adding blocks to the chain.
Full nodes work to validate every transaction and block on the network. The more nodes a network has, the more secure it becomes, decreasing the possibility of a 51% attack. As more nodes join the network, the database is distributed into more locations, ensuring it stays decentralized.
Other types of nodes may not validate every single transaction. They may contribute to network security without mining or by simply relaying data between other nodes in the network.
What are Nodes Used For?
Blockchain nodes are used to confirm transactions on the network. For example, as Bitcoin transactions are submitted, nodes start to verify the transactions in each block, making sure the data is accurate. Nodes not only verify new transactions, they also keep a record of the blockchain history, mine new blocks in the chain, and secure the network.
It’s important for a blockchain that enough people using the network participate by running a node. This helps to keep the network from becoming vulnerable to attack. If the majority of users only send transactions but don’t run a node, they are not contributing to the stability of the network. Nodes can be run by companies, communities, and individuals through their own DIY systems or dedicated servers and platforms available globally.
How Do Nodes Work?
Nodes connect to the network and download an updated copy of the distributed ledger from other nodes. They also then receive transaction data from the mempool, or memory pool, and confirm transactions. To confirm a transaction, details must be validated to ensure the transaction meets network requirements. It’s also necessary to verify that a sender has sufficient funds to complete the requested transaction.
Miner nodes create blocks by solving mathematical equations. Once a hash is solved, the new block is sent to the rest of the network and other nodes work to verify the block. Nodes also transmit updated copies of the ledger to ensure decentralized distribution and network security.
Interesting Information about Nodes
- In 2023, there were 17,379 reachable nodes on the Bitcoin blockchain and 9.77% are in the USA
- To set up a full Bitcoin node, you need 350 GB of space, 500 MB/day of download data, 5 GB/day of upload data, and 1 GB of RAM
- There are several kinds of blockchain nodes including full nodes, mining nodes, and light nodes
Node Related Terms
Blockchain — A blockchain is a decentralized database that records transactions on a distributed ledger.
Mining — Blockchain mining is the process of adding new blocks of transactions to the database. Mining nodes hash blocks and confirm transactions, updating the ledger.
Proof-of-Work — An blockchain-based algorithm that uses computing power to secure the network.
Hash Rate — A hash rate (or hashrate) measures the total computing power used on a proof-of-work blockchain. It measures the number of nodes hashing blocks on the network.
Bitcoin Halving — A Bitcoin halving is a mechanism that is encoded into the Bitcoin protocol to control the rate at which new bitcoins are created.