Over the years, blockchain technology has gained significant popularity and wide adoption due to its decentralized, reliable, and secure nature.
Blockchain technology offers a great alternative to traditional systems. Traditional platforms rely on a central authority to maintain the system and process the transactions between members.
This centralized approach comes with its own drawbacks which blockchain technology is aiming to address.
The technology eliminates the need for middlemen by allowing participants to transact directly with each other using a peer-to-peer (P2P) decentralized network.
To make this possible, blockchain technology uses a unique way of storing data which is then used by members of the system for transaction processing and verification.
These members of the blockchain that are responsible for validating transactions and maintaining the system are called nodes.
Blockchain nodes come in different types and can take on various roles on a blockchain.
Blockchain nodes play an important role in the operation of a blockchain platform so it’s always a good idea to learn more about them.
In this article, you will learn about blockchain nodes, their various types, and their functionalities.
Before getting into blockchain nodes, let’s talk a bit about blockchain technology and how it functions.
Simply put, blockchain is a decentralized database. All the information in the system is kept in the blockchain ledger which stores the data in chunks called Blocks.
These blocks are linked together using mathematical techniques which makes it really hard to change and manipulate them.
Blockchain is run and maintained by its members also known as blockchain nodes.
A blockchain node is simply any individual computer or device attached to a blockchain network by running its application.
Based on the type of the blockchain, a blockchain node may require specific computation capacity to be able to validate transactions, mine or propose new blocks, and help with the network’s security.
As distributed networks, the security of a blockchain is dependent on the number of nodes that are maintaining the system.
Each node holds a copy of the blockchain ledger which is then used for validating transactions.
There are no limits to the number of nodes that can be connected to a blockchain network. However, the number of nodes on a blockchain network can vary depending on the design, functions, and nature of the blockchain.
Anyone with the technical knowledge and resources including individuals, organizations, or even governments can run a blockchain node.
We can categorize blockchain nodes into three broad categories: Full Nodes, Light Nodes, and Masternodes.
Let’s take a quick look at these blockchain nodes and the functions and characteristics of each.
This category of blockchain nodes is essential for maintaining the integrity of the blockchain as they have the capacity to store a complete copy of the ledger.
Full nodes are essential to blockchain security as they are a vital part of the system’s consensus. Most major upgrades and updates need to be confirmed by the majority of full nodes.
These nodes are responsible for verifying new blocks and transactions and ensuring that every new transaction and block on a network is duly verified.
Full nodes may have different roles.
Unlike full nodes, light nodes don’t hold a complete copy of the blockchain network ledger.
Instead of keeping the complete list of transactions, they only receive the required information from other nodes to be able to verify transactions. This makes them faster than full nodes.
A Simplified Payment Verification (SPV) client is a specific type of light node that doesn’t verify transactions.
We can use these clients to check and see whether a specific transaction is included in a block, or not.
Masternodes are not involved in adding new blocks to the blockchain network, however, they are responsible for verifying the proposed blocks, and picking the lucky node.
Masternodes are mostly used in Proof-of-Stake (PoS) blockchains and can take on other important governance roles.
For the proper functioning and security of a blockchain system, the different types of nodes on a network work together and not independently.
Full nodes, light nodes, and masternodes have to communicate with each other at all times to be able to maintain their own copy of the ledger updated and similar to other members of the network. In this way, the integrity of the network will remain intact.
In a PoW blockchain, mining nodes are responsible for adding new blocks to the system. They broadcast their proposed block to the network which has to be approved by other nodes.
Each node validates the new block according to its copy of the ledger and if approved, adds it to the chain. Once the majority of nodes have accepted the new block and included it in their ledger, the new block is officially added to the blockchain.
The process is determined by the consensus mechanism of a blockchain which instructs nodes how to reach an agreement on the addition of a new block to the chain.
The consensus mechanism helps members of a distributed system to be able to maintain the network in an integrated state without a centralized authority.
As mentioned, blockchain nodes are the building blocks of any blockchain network. They take on different roles in a blockchain system and are the key foundations that ensure a network is reliable, secure, and transparent.
Here are some of the reasons why blockchain nodes are important:
❖Transaction Validation: Blockchain nodes are responsible for verifying transactions in a blockchain network. Mining or staking nodes then use these verified transactions to form new blocks which are then added to the chain. This helps to ensure that only valid blocks are added to the chain, maintaining the integrity of the network.
❖Security: If there are more nodes connected to a network, the security of the blockchain network becomes stronger. Blockchain nodes help to make a network secure by storing a copy of the blockchain in different devices. This makes it difficult for bad actors to manipulate the network or commit fraud.
❖Decentralization: Another notable function that nodes offer is the enhancement of a decentralized blockchain environment. By allowing multiple computers to participate in the consensus mechanism of a network, governance is not done by a central authority but collectively.
❖Transparency: Additionally, nodes of a public blockchain allow everyone to be able to check the ledger of the blockchain and its transactions. This feature creates a transparent system which can further reduce the chances of fraud and manipulation.