The node definition can vary significantly according to the context in which it is used. When it comes to computer networks or telecommunications, nodes can be used for distinct purposes, acting as a redistribution point or as a communication endpoint. Usually, a node is a physical network device, but in some specific cases, virtual nodes are used.
Simply put, a network node is a point at which a message can be generated, received, or transmitted. Accordingly, we will discuss the different types of Bitcoin nodes: full node, super node, miner node, and SPV client.
Node Bitcoin
Putting it into context, blockchain – designed as a distributed system – network of computer nodes makes it possible for Bitcoin to be used as an unregulated peer-to-peer (P2P) digital currency. browsing thanks to its design and without the need for an intermediary to conduct transactions between users (regardless of geographical distance in the world).
Therefore, blockchain nodes are responsible for serving as a communication point that can perform various functions. Any computer or device connected to the Bitcoin interface can be considered a node because they generally communicate with each other in some way. These nodes can also transmit information about transactions and blocks in a distributed computer network using the Bitcoin peer-to-peer protocol. However, each computer node is defined by its specific functions, so there are different types of Bitcoin nodes.
Full Node (Full Node)
Full nodes are nodes that actually support and provide security for Bitcoin. These nodes are indispensable to the network. These nodes are also called full validator nodes because they participate in the process of verifying transactions and blocks before the system's consensus rules. Full nodes can also relay new transactions and blocks to the blockchain.
Typically, a full node downloads a copy of the bitcoin blockchain with each block and transactions on it, but this is not a requirement to be considered a full node (a reduced copy of the blockchain can be used). replace).
A Bitcoin full node can be set up through different software implementations, but the most used and popular is Bitcoin Core. These are the minimum requirements to run a Bitcoin Core full node:
A desktop or laptop computer with a recent version of Windows, Mac OS X, or Linux installed.
200GB of free hard drive space.
2GB memory (RAM).
High-speed internet connection with minimum upload speed of 50 kB/s.
Unlimited connections or connections with high upload limits. Full nodes can reach or exceed upload usage of 200 GB/month and download usage of 20 GB/month. You will also need to download about 200GB when you first launch a full node.
Your full node should run at least 6 hours a day. Even better if you run it continuously (24/7)
Many organizations and volunteer users are running Bitcoin full nodes as a way to support the Bitcoin ecosystem. Currently, there are approximately 9,700 public nodes running on the Bitcoin network. Note that this number only includes public nodes that are visible and accessible Bitcoin listening nodes (also known as listening nodes).
Besides public nodes, there are many other hidden nodes that are not visible (non-listening nodes). These nodes often operate behind firewalls, through hidden protocols like Tor, or simply because they are configured not to receive connections.
Listening Node (Super Node)
Essentially, a listening node or super node is a full node whose connection is public. It communicates and provides information to any other node that decides to establish a connection with it. Therefore, a super node is essentially a redistribution point that can play dual roles as a data source and a communication bridge.
A trusted super node typically runs 24/7 and has several established connections. This node transmits blockchain history and transaction data to many nodes around the world. For that reason, a super node may require more computing power and a better internet connection when compared to a hidden full node.
Miner's node
To be able to mine Bitcoin in the current competitive situation, miners must invest in specialized hardware and mining programs. These mining programs (software) are not directly related to Bitcoin Core and run in parallel to mine Bitcoin blocks. A miner can choose to work alone (solo miner) or in a group (pool miner).
While solo miners' full nodes leverage their own copy of the blockchain, miner pools work together, each contributing their own computational resources (hashpower). In a mining pool, only the pool administrator needs to run a full node - which can be called the pool miner full node.
Lightweight Client, also known as SPV Client
Also known as the Simplified Payment Verification (SPV) client, the lightweight client is a client that leverages the Bitcoin network but does not actually function as a full node. Therefore, the SPV client does not contribute to the security of the network because it does not keep a copy of the blockchain and does not participate in the transaction verification and validation process.
In short, SPV is a method through which users can check whether certain transactions are included in a block without having to download the entire block data. Therefore, the SPV client relies on information provided by other full nodes (super nodes). Lightweight clients act as communication endpoints and are used by many cryptocurrency wallets.
Client Node và Mining Node
It is important to note that running a full node is not the same as running a full mining node. While miners have to invest in expensive mining hardware and software, anyone can run a full validation node. Furthermore, before attempting to mine a block, miners need to collect pending transactions that have previously been accepted as valid by full nodes. Next, the miner generates a candidate block (with a set of transactions) and attempts to mine that block. If a miner finds a valid solution for that block, he will announce it on the network and other full nodes will verify the block's validity. Therefore, consensus rules are decided and guaranteed by a distributed network of validating nodes and not by miners.
Conclude
Bitcoin nodes communicate with each other via the Bitcoin P2P network protocol. By doing so, they ensure the integrity of the system. A node that fails or tries to transmit incorrect information will quickly be recognized by honest nodes and will be disconnected from the network.
Despite the fact that running a full authentication node does not receive a financial reward, it is still encouraged because it provides trust, security, and privacy to users. Full nodes ensure that the rules are being followed. They protect the blockchain against attacks and fraud (such as double-spending). In addition, full nodes allow users to have full control over their funds because there is no need to entrust them to others.