A “Light Node,” also known as a “Lite Node” or “SPV Node” (Simplified Payment Verification Node), refers to a type of client or participant in a blockchain network that doesn’t download and store the entire blockchain. Instead, it relies on a more lightweight approach to interact with the network, enabling faster synchronization and reduced resource requirements compared to a full node.
Key Characteristics of a Light Node
Reduced Data Storage: Unlike a full node, which stores the entire transaction history and state of the blockchain, a Light Node only maintains a subset of the blockchain data. It typically stores block headers, transaction headers, and relevant information needed for its specific operations.
Verification through Simplified Payment Verification (SPV): Light Nodes use SPV to verify transactions. Instead of validating the entire blockchain, they only request and verify block headers and a subset of transactions relevant to their own activities. This allows them to confirm the inclusion of a specific transaction in a block without the need to download the entire block.
Faster Synchronization: Because Light Nodes don’t download the entire blockchain, they can synchronize with the network more quickly. This makes them suitable for applications where rapid access to transaction information is crucial, such as mobile wallets or other resource-constrained environments.
Lower Resource Requirements: Light Nodes have lower hardware and bandwidth requirements compared to full nodes, making them more accessible for users with limited resources or those operating on devices with constraints, such as mobile phones.
Dependence on Full Nodes: Light Nodes rely on full nodes to access blockchain information. They connect to full nodes to request the data they need, ensuring they have the latest and most accurate information for verification.
The trade-off with Security: While Light Nodes offer advantages in terms of resource efficiency and faster synchronization, they come with a trade-off in terms of security. Since they don’t independently validate the entire blockchain, they rely on the assumption that the majority of the network’s hash power is honest and follows the consensus rules.
Light Nodes are commonly used in scenarios where maintaining a full copy of the blockchain is impractical or unnecessary. They provide a balance between resource efficiency and security, making them suitable for applications where a full node’s robustness is not essential and rapid access to transaction information is prioritized. Mobile wallets, lightweight clients, and certain blockchain applications often leverage Light Nodes to enhance user experience.