The term “node” has long existed in computer science or even in medicine, but in recent months and years it has appeared significantly more frequently in the context of blockchain. Any computer, device, or even person that is connected to the network is considered a node. A node receives, processes, distributes or sends data into the network and thus contributes to the linking of the individual nodes. More generally, nodes can also be routers, switches or gateways, i.e. individual network components.
In the context of blockchain technology, a distinction is made between light nodes and full nodes. To secure the blockchain, each node checks whether the data is correct and whether the corresponding authorization to receive, process or forward the data exists. Full Nodes own a complete copy of the Blockchain and thus check all information in detail. Light Nodes do not own a full copy of the Blockchain, but only a part of it. This part can be, for example, the header or a few blockchain lines on the basis of which the check is performed. This allows light nodes to verify a transaction of a block within the blockchain without having to download the entire block right away. Light Nodes are easier to operate, require fewer resources (energy, storage space) and less computing power. (Simplified illustration)
For the efficient and secure use of blockchain, a combination of full nodes and light nodes is recommended. Nodes in this context are often also referred to as Lightweight Nodes or else Light Wallets.
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