A blockchain is not a server somewhere. It is a network of thousands of computers — called nodes — each running the same software and holding the same copy of every transaction ever recorded. When you send a tokenized asset from one wallet to another, that transaction is verified and recorded by nodes, not by a bank or a company's database.
The franchise owner analogy is useful here. McDonald's corporate sets the rules — the menu, the standards, the procedures. Franchise owners run individual locations according to those rules. Nodes are like franchise owners: they agree to follow the blockchain's protocol, and in return they earn the right to participate in validating transactions and, depending on the network, earn rewards for doing so.
What Nodes Actually Do
Every full node on a blockchain does three things: it receives new transactions, it checks whether those transactions are valid (does the sender actually have the tokens they claim to send?), and it adds valid transactions to its copy of the ledger. Every other full node on the network is doing the same check simultaneously. A transaction is not final until a majority of nodes have agreed it is valid — which is why blockchain transactions are considered irreversible once confirmed.
This distributed verification is what makes blockchain different from a database. In a traditional database, one company controls the records. If that company makes an error, gets hacked, or chooses to change the records, the records change. On a blockchain, changing any historical record would require convincing the majority of thousands of independent nodes to accept the change simultaneously — which is computationally prohibitive on large networks.
Types of Nodes
Full nodes hold a complete copy of the blockchain's transaction history. Running one requires significant storage (the Ethereum blockchain is several terabytes as of 2026) and bandwidth. Full nodes are the backbone of the network's security.
Light nodes (also called light clients) do not hold the full history. They rely on full nodes to verify transaction data and are used by wallets and mobile applications where full storage is impractical.
Validator nodes (on proof-of-stake networks like Ethereum) do the active work of proposing and confirming new blocks. Running a validator node requires staking — locking up cryptocurrency as collateral against bad behavior. Validators earn rewards for honest participation.
Archive nodes hold not just the current state of the blockchain but the full historical state at every block — useful for analytics and research but resource-intensive.
Why This Matters for RWA
Real-world asset tokenization runs on top of blockchain networks. The security and decentralization of the underlying network — which is a function of how many nodes are running and how distributed they are — directly affects the security of the tokenized assets on top of it. A tokenized Treasury token on Ethereum benefits from Ethereum's tens of thousands of nodes. A tokenized asset on a small private chain with five nodes has much weaker security guarantees.
Node infrastructure also affects transaction cost and speed. Networks with more nodes and higher activity tend to have higher transaction fees during congestion. Layer 2 networks — which process transactions off the main chain and settle them in batches — reduce this cost significantly, which is why many RWA platforms are built on Layer 2 networks like Polygon, Arbitrum, or Avalanche rather than Ethereum mainnet directly.
→ What Is a Smart Contract? — what runs on top of the node network
→ RWA Token Standards — how assets are structured on these networks