What are Nodes?

What are General Nodes?



Nodes are users that operate through their hardware devices and computers to maintain the state of decentralization present in the system. This results in the elimination of any third party which may centralize the network. Nonetheless, the system is still able to sustain itself with the aid of the users’ collective efforts of verifying transactions in the consensus algorithm.



In this article, we will explore the various types of nodes present in the Bitcoin blockchain network, along with their accompanying duties.





What are Bitcoin Nodes?



In detail, Bitcoin nodes include all types of nodes in the network. In general, their duties are to look over and validate transactions, while also communicating with other fellow nodes to create the consensus algorithm.

However, the nodes can be divided further, as according:



1. Full Nodes



Full nodes are highly important to the network’s integrity as they serve as monitoring and supporting agents within the blockchain itself. Other than verifying and confirming the validity of transactions, full nodes also help by transferring copies of blockchain transactions to other nodes to ensure mutual agreement of the consensus. 



Therefore, hardware devices running as full nodes are required to download all transaction data present in the blockchain, from the first to last block. This inevitably means that they are required to have the memory capacity of at least 200 GB, or more in contemporary times, while also running their devices at least 6 hours a day as well. As for software, full nodes have a variety to choose from, but the most popular is Bitcoin Core.



2. Miner Nodes



This set of nodes is responsible for mining coins through resolving complex mathematical equations and verifying transactions with other nodes, which can also be referred to as miners, in this respect. In competition, the miner that successfully solves the equation would receive rewards as newly created BTC. To compete with other miners, a miner node is required to be equipped with well-functioning GPUs or ASICs.



Miners can operate individually or as a pool (in groups) to help provide an increase in computational power, wherein rewards for creating a new block would be distributed. However, in some situations, miner nodes are not required to download the entirety of a blockchain’s transactions, depending on the software in use, but the administrator of the respective pool is indeed required to download its entirety.



3. SPV



Simplified Payment Verifications or SPVs, are nodes that are responsible for communicating within the Bitcoin blockchain, but are not involved in the verification process and are not required to download the entirety of the blockchain’s transactions. SPV nodes’ main duty is to display and communicate information in the blockchain, acting as a wallet.





Conclusion



Users in the Bitcoin blockchain are referred to as nodes, which operate and communicate in a peer-to-peer manner. Though a categorization is in place, every node is responsible for analyzing and verifying transactions, while also maintaining the network’s security, integrity, and transparency within a decentralized network to not require the employment of a central authority.





Reference



Binance Academy, Medium, InfoQ