What are blockchain nodes: types, functions, and requirements for running them

What are nodes in cryptocurrency?

Blockchain is a decentralized computer network in which each device acts as a separate node. These nodes store copies of the blockchain, creating a distributed database.

What are nodes?

A blockchain node is a network node within a blockchain that performs various functions, such as storing a copy of the distributed database, validating transactions, and producing new blocks.

Nodes in crypto interact with one another within a blockchain network to reach consensus, for example, on which transactions and blocks should be added to the network. This approach underlies all well-known consensus algorithms, such as Proof-of-Work (PoW), Proof-of-Stake (PoS), Proof-of-Authority (PoA), Proof-of-History (PoH), and many others.

It is blockchain nodes in cryptocurrency that help ensure the security of a decentralized network: the more nodes there are, the harder it becomes to manipulate blockchain data or carry out various attacks, such as a 51% attack*.

* A 51% attack is an attack on a blockchain in which a single participant or a coordinated group gains control of more than 50% of the network's computing power. This advantage allows the attacking party to build an alternative blockchain faster than other participants and influence which version of the transaction history is recognized as the main one. As a result, an attacker may potentially reverse their own previously completed transactions, spend the same funds more than once, and prevent certain transactions from being confirmed.

Almost any user can run a blockchain node on their own device as long as they meet the minimum node requirements, which are set separately for each network. For example, running a full blockchain node on the Bitcoin network requires at least 900 GB of hard drive space and more than 4 GB of RAM.

What types of nodes exist in a blockchain?

Depending on the architecture of a particular network, there may be different types of blockchain nodes. For example, the Bitcoin network has three main types of nodes in the blockchain:

Full nodes, which store the entire blockchain history. Full nodes also participate in network consensus: they validate blocks and transactions before relaying them for inclusion in the blockchain;
Light nodes, also known as SPV nodes*. Such nodes in cryptocurrency download only a small portion of blockchain data and are primarily intended for devices with limited storage and computing power, such as smartphones and low-performance computers. Light nodes in crypto interact with the blockchain network much faster than full blockchain nodes.
Miner nodes. These blockchain nodes are responsible for validating transactions and mining new blocks, for which they receive rewards in the network's native cryptocurrency, for example, BTC in Bitcoin, DOGE in Dogecoin, LTC in Litecoin, and so on.

* SPV (Simplified Payment Verification) is a simplified method for verifying blockchain payments in which a node does not download or store the entire blockchain history. Instead, the blockchain node receives block headers and requests the data needed to verify specific transactions from full nodes. This reduces the device's memory, storage, and computing resource requirements.

Full nodes in the Bitcoin blockchain, in turn, are divided into two types:

Archival full nodes;
Pruned or "trimmed" full nodes.

Archival nodes in cryptocurrency contain a complete copy of the entire transaction history in the blockchain, starting from the launch of the Bitcoin network and the mining of the first block. In contrast, pruned nodes in crypto first save a complete copy of the blockchain to verify its authenticity and then delete some data from older blocks to free up storage space on the device.

Other networks may have additional types of blockchain nodes. For example, PoS blockchains have validator* blockchain nodes. Like miner nodes, they validate transactions and produce new blocks, but instead of solving mathematical problems, they rely on a staking* mechanism. Under this mechanism, validators lock at least a certain amount of the network's native cryptocurrency in the protocol to support the network, such as ETH in Ethereum, BNB in BNB Chain, SOL in Solana, and so on.

* Validator is a participant in a network that uses the Proof-of-Stake (PoS) consensus mechanism and takes part in validating transactions, confirming the correctness of new blocks, and maintaining the operation of the network. The right to participate in this process is determined not by computing power, as in Proof-of-Work (PoW) mining, but by an economic stake in the form of locked coins. A validator receives rewards for correct operation, while their locked coins may be confiscated for violating network rules.

* Staking is a way of participating in the operation and security of a blockchain that uses the Proof-of-Stake (PoS) consensus mechanism, in which a participant locks a certain amount of the native cryptocurrency as collateral. This stake demonstrates the participant's (validator's) economic interest in acting honestly and allows them to participate in creating and confirming new blocks.

Validator blockchain nodes are also called staking nodes. However, validator nodes may have different names across different networks despite performing similar functions. For example, on the EOS network, validator blockchain nodes are called block producers (BPs); on TRON, they are called Super Representatives (SRs); and on Tezos, they are called bakers.

In addition to technical requirements, running validator blockchain nodes also involves minimum deposit requirements, meaning a certain amount must be locked in the network protocol. For example, running an Ethereum validator blockchain node requires at least 32 ETH, which as of August 2026 is approximately $60,000.

In addition to minimum requirements, some networks do not allow users to launch their own blockchain node because they must first pass a strict selection process. Depending on the network, this may happen in different ways:

Through voting;
Through random selection;
Algorithmically.

Some networks also have specialized types of nodes in cryptocurrency, such as masternodes in the Dash blockchain. Masternodes have expanded functions and privileges:

PrivateSend — sending transactions with enhanced privacy;
InstantSend — instant transaction processing.

However, the requirements for running masternodes are also higher than those for ordinary blockchain nodes. For example, running a masternode on the Dash network requires collateral of at least 1,000 DASH, which as of August 2026 is worth more than $35,000.

The Lightning Network (LN) payment network, which operates as a second layer on top of Bitcoin, uses Lightning nodes. These blockchain nodes form payment channels that interact with one another and transmit information about their balances to the main Bitcoin network.

Why do users run their own blockchain nodes?

Running your own blockchain node is far from necessary for every cryptocurrency holder, but it does offer several advantages. A user can independently verify transactions and blocks, rely less on third-party servers and services, and participate in maintaining the network's distributed infrastructure.

For developers and cryptocurrency services, running their own blockchain nodes also makes it possible to access blockchain data directly and submit transactions to the network without relying on third-party API providers for every operation.

However, this independence comes at the cost of resources: a cryptocurrency node must be installed, synchronized, updated, secured, and provided with a stable internet connection.