Crypto
3 min read

Node

Any computer that participates in a blockchain network by storing and propagating data. Nodes can be full (verifying everything), light (verifying headers), or specialized (e.g., archive, validator).

What nodes do

Different node types have different roles:

  • Full nodes — verify everything; maintain complete state and history.
  • Light nodes — verify subset; rely on full nodes for some data.
  • Archive nodes — full state plus historical snapshots; useful for analytics.
  • Pruning nodes — full nodes that drop old state to save disk.
  • Validator / miner nodes — produce or attest to new blocks.
  • RPC nodes — serve data to applications and users.

A blockchain network is the collective set of all these nodes operating together.

What network nodes provide

The functions:

  • Verification. Each full node enforces protocol rules; collectively they define what the chain "is."
  • Censorship resistance. Distributed nodes make individual censorship impossible.
  • Data availability. Multiple nodes ensure historical data remains accessible.
  • Connectivity. Nodes propagate transactions and blocks throughout the network.
  • Service provision. RPC nodes serve data to wallets, dApps, and indexers.

Bitcoin and Ethereum node counts

Approximate scale:

  • Bitcoin — ~15,000-20,000 reachable full nodes globally.
  • Ethereum — ~5,000-10,000 reachable full nodes.
  • Validator counts — Ethereum has ~1M+ validators; Bitcoin doesn't have validators (uses miners).

These numbers are healthy from a decentralization perspective but somewhat concentrated in cloud infrastructure.

Running a node

Resource requirements vary:

  • Bitcoin full node — 600+ GB SSD, 4 GB RAM minimum, reliable internet.
  • Ethereum full node — 1+ TB SSD (NVMe recommended), 16 GB RAM, reliable internet.
  • Solana validator — multi-TB SSD, many cores, fast network.
  • Various other chains — varying requirements.

For Bitcoin, individuals can run nodes practically. For higher-throughput chains, requirements increase substantially.

Why running a node matters

Several practical benefits:

  • Self-verification. Don't trust third-party RPC services; verify yourself.
  • Privacy. Your queries don't leak to third parties.
  • Network contribution. Your node helps the network's overall health.
  • Reliability. Not dependent on any single RPC provider.

RPC providers

Most users don't run nodes directly:

  • Alchemy, Infura, QuickNode — major Ethereum RPC services.
  • Chain-specific RPC services for various chains.
  • Built-in wallet RPCs — wallets often integrate RPC services automatically.

These provide convenience but introduce dependency. If they fail or get compromised, applications relying on them fail.

Node centralization concerns

A persistent worry:

  • Many full nodes run on cloud providers (AWS, Hetzner, others).
  • Cloud-provider concentration creates potential single points of failure.
  • Geographic distribution is real but limited.
  • RPC service concentration affects how dApps access chains.

These don't directly compromise network security but produce subtle centralization risks.

In broader infrastructure

Nodes are one layer in deeper stack:

  • Mining/validation hardware at the bottom for produced chains.
  • Full nodes for verification.
  • Indexers and analytics consuming chain data.
  • APIs and RPC services abstracting node operation.
  • Wallets and dApps consuming services.

Each layer can be more or less centralized; node decentralization is one component of overall chain decentralization.

What individuals should know

For most users:

  • You don't need to run a node for most use cases.
  • Wallet apps handle complexity through RPC services.
  • Running a node adds privacy and verification benefits but operational cost.

For high-value holders or privacy-sensitive users:

  • Running your own Bitcoin node is practical and provides meaningful benefits.
  • Ethereum nodes require more resources but provide similar advantages.
  • Specialized tools (Umbrel, MyNode) make running nodes accessible without deep technical expertise.

For developers:

  • Reliable RPC access is critical infrastructure.
  • Backup RPC providers reduce single-point-of-failure risk.
  • Self-hosted nodes for production-critical applications.

The basic principle: nodes are the network. Even users who don't run them benefit from their collective operation. Running one when feasible adds personal benefits and supports the network's decentralization.