There are 2 types of Ethereum nodes:
Layer 1 nodes
Layer 2 nodes
A Layer 1 Ethereum node is responsible for validating and propagating transactions and blocks across the main network. Layer 1 nodes play a key role in maintaining the security and decentralization of the Ethereum network.
Layer 2 Ethereum nodes, or L2 nodes, refer to off-chain scaling solutions built on top of the Ethereum blockchain to improve its scalability, throughput, and transaction speed.
Layer 1 node
If you run an Ethereum L1 node you are contributing to the health and decentralization of the network.
You can use your own node to verify all the Ethereum transactions (no need to trust a third party), send your own transactions or query the blockchain for further info.
There are three node setups that you can run with your ARM board:
A Full Ethereum node (Execution Layer + Consensus Layer Beacon Chain)
An Archive Ethereum node (Execution Layer + Consensus Layer Beacon Chain)
A Staking node (Full/Archive node + Consensus Layer Validator node + 32 ETH deposit)
Full Ethereum node
Definitions from ethereum.org
Stores full blockchain data (although this is periodically pruned so
a full node does not store all state data back to genesis) * Participates in block validation, verifies all blocks and states. * All states can be derived from a full node (although very old states are reconstructed from requests made to archive nodes). * Serves the network and provides data on request.
This is the default mode for all clients. In order to run a Full node you need an Execution Layer Client and a Consensus Layer Client (just the Beacon Node part).
Erigon includes a light Consensus Client by default so if you use this client and you are not going to stake you can run a full node just by starting the Erigon service.
Archive Ethereum node
Definitions from ethereum.org
Stores everything kept in the full node and builds an archive of historical states.
It is needed if you want to query something like an account balance at block #4,000,000, or simply and reliably test your own transactions set without mining them using tracing. * This data represents units of terabytes, which makes archive nodes less attractive for average users but can be handy for services like block explorers, wallet vendors, and chain analytics.
If you want to start an archive node you need to run Erigon or Reth client. Take into account that you will need a 4 TB SSD disk and the sync time will take several days.
If you want to contribute to the Ethereum security you can become a Validator and stake your ETH. You can do so by depositing 32 ETH into the mainnet staking contract and creating a pair of keys to run a Consensus Layer Validator. The CL Validator will propose new blocks and make attestations on blocks created by other validators.
You will need:
A synced Ethereum node (Execution Layer Client + Consensus Layer Beacon Chain Client)
A Consensus Layer Validator
Layer 2 node
Layer 2 solutions include various technologies, such as state channels, sidechains and rollups (like Optimistic Rollups and ZK-Rollups). These solutions offload some of the computational load from the main Ethereum blockchain, allowing for faster and cheaper transactions.
Layer 2 nodes are responsible for maintaining the integrity and security of the off-chain transactions and state changes. They ensure that these transactions are valid and follow the rules of the Layer 2 protocol before they are eventually committed back to the Ethereum Layer 1 blockchain.
Ethereum on ARM supports the following L2 solutions: