Node is the main element of blockchain: types, functions, and role in the network

A node is not just a computer on the network — it is an active participant in the blockchain ecosystem responsible for distributing information and ensuring the operation of the entire system. A node is a blockchain node that performs critically important functions: from verifying transactions to maintaining a complete history of the blockchain.

A node is the foundation of decentralization: how network nodes operate

At a fundamental level, a node is a computer or server equipped with special software and synchronized with other network nodes. Together, many such computers form a distributed architecture that enables the rapid movement of large data flows without a central control point.

A node is the workhorse of the blockchain. Each node performs three key tasks: storing transaction and wallet balance information, monitoring compliance with network rules (consensus algorithm), and maintaining the operation of the distributed ledger with the entire transaction history.

A key feature is that a node is always an online system. An offline device cannot function as a full network node. Only a computer connected to the internet can participate in data synchronization and information exchange with other participants.

Why the network cannot function without numerous nodes

A node guarantees the decentralization of a cryptocurrency network. If all nodes are controlled by a single organization, it would gain full control over the blockchain, violating the core principle of distributed systems.

Thanks to the geographical distribution of nodes (located in different countries and cities), even internet restrictions in one region won’t stop the network from functioning. The system will continue to operate through nodes elsewhere. A node is a bastion of stability — each node stores a full copy of the data, so the network is protected against data loss.

Projects incentivize owners to run nodes through reward systems. Those providing computational power to support the blockchain earn income via fees or special payouts.

Full nodes: archive and validator of the entire blockchain

A full node is the most reliable type of node. It is a storage device — containing a complete archive of all transactions and blocks from the network’s inception to the present. When the Bitcoin network reached 438 GB of data in November 2022, each full node needed to have that much storage.

During initial setup, a full node synchronizes completely, downloading the entire blockchain. For Bitcoin, this can take several weeks due to the massive data volume. After disconnecting, the node must re-synchronize to catch up with missed data upon reconnecting.

A node is not just storage — it actively validates. Full nodes verify digital signatures and keys, validating each transaction and block. If a node detects an error (incorrect formatting, duplication, data manipulation), it rejects the operation.

Owners of full nodes can independently verify incoming transfers and, if network conditions permit, participate in mining, earning material rewards.

Light nodes and specialized node types

A light node is a simplified version of a node. Unlike full nodes, a light node only stores information about the specific block it connects to. It is software that connects to a full node and receives data on balances and transactions for further user access.

The advantage is that a light node has minimal requirements for computing power and memory. Such a node can be easily run even on a smartphone, and synchronization takes only seconds.

A pruned full node is a hybrid. It downloads the entire blockchain at first launch but then automatically deletes old blocks once a set size (e.g., 10 GB) is reached, keeping only the most recent data.

Mining nodes vs. staking nodes: hardware choices

A mining node is a node involved in creating new blocks by solving complex mathematical problems (Proof of Work algorithm). It is a computational center requiring powerful hardware: CPUs, GPUs, or specialized chips (ASICs).

A staking node is analogous for Proof of Stake blockchains. It does not require expensive equipment. Rewards are earned for holding a certain amount of coins in the account, not for computations. After Ethereum’s major upgrade in September 2022 (known as The Merge), the blockchain fully transitioned from PoW to PoS, replacing mining nodes with staking validators.

Masternodes: advanced functions and income

A masternode is an advanced version of a full node. It is a node with special functions: it stores a full archive of the blockchain like a regular node but also offers additional capabilities, such as ensuring privacy through transaction fragmentation and rerouting between wallets.

The owner of a full node can activate a masternode by fulfilling network requirements: usually, this involves depositing a certain amount of coins and configuring the server. In return, the system pays the owner a portion of miner fees.

In the context of masternodes, a node can also be used for mixing. During anonymous transactions, coins are “mixed” through several randomly selected masternodes worldwide. The result is that it becomes impossible to trace the sender and receiver.

NEM (XEM) uses a special variant called a supernode, which operates on a similar principle.

Lightning nodes and additional functions

The Lightning Network is a second-layer network built on Bitcoin. A node here is a special node synchronized with other Lightning nodes and the main blockchain. The key difference: a node only verifies transactions directly related to it, not all operations in the blockchain, enabling extremely fast payments.

Validators are nodes that verify and approve transactions according to the rules of a specific blockchain. Oracles are nodes that transmit data from external sources into the blockchain — for example, current exchange rates for trading services. Script-oracles convert this data into a format understandable by smart contracts.

How blockchain updates change node functions

Any cryptocurrency project periodically upgrades. A node is an element that must adapt to these changes. The process of implementing updates is called a fork.

A soft fork involves minor improvements that do not break the core rules of the network. To adopt them, node owners simply update their software. The network continues to operate stably even if some nodes lag behind with updates.

A hard fork involves radical changes. In this scenario, a node can completely change its type or functions. Disagreements within the community about a hard fork can split the network into two incompatible blockchains — one maintaining old rules, the other adopting new ones.

A node is a living organism of the blockchain, constantly adapting to technical changes and the evolving network requirements.