What is Validium

Validium is a blockchain scaling solution that processes transactions and stores data off-chain to improve the throughput of the mainnet. 

What is scaling? How does it work? Please refer to the content: What is Layer 2

In other words, it takes the execution and data availability layers of a layer 1 blockchain off-chain. Validium takes advantage of validity proofs to guarantee the integrity of off-chain transactions, which is the same as zero-knowledge roll-ups. 

What does “zero-knowledge” mean? Please refer to the content: What is Zero-Knowledge Proof

However, zero-knowledge roll-ups post compressed transaction data on the mainnet, while Validium stores transaction data off-chain with a data provider to further reduce cost and improve performance. 

Validium only relies on layer 1 for settlement and consensus. Immutable X is an example of a Validium. Arbitrum Nova also takes execution and data availability off-chain. But it does not use validity proofs, so it is technically not a Validium.

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• What is Sharding?
• What is Blockchain Trilemma?