Volition is a data availability (DA) mode where users choose on a per-transaction basis whether their transaction data is stored on-chain (like a rollup) or off-chain with a data availability committee (like a validium). First proposed and built by StarkWare, Volition gives users and dApps flexibility to trade security guarantees for cost savings.
The DA Spectrum
| Mode | Data Storage | Security | Cost |
|---|---|---|---|
| Rollup | On Ethereum L1 | Highest — anyone can verify | Higher |
| Volition | User’s choice per-tx | Flexible | Flexible |
| Validium | Off-chain (DAC) | DAC trusted | Lowest |
How Volition Works
In a Volition system, each transaction carries a flag:
ZK-Rollup mode:
- Transaction data posted to Ethereum
- Anyone can reconstruct state from L1
- Higher gas cost
Validium mode:
- Transaction data sent to a trusted Data Availability Committee (DAC)
- Only a hash/commitment posted to Ethereum
- DAC members sign attestations that data is available
- Lower cost, but requires trusting DAC won’t collude
Users and applications select which mode based on their risk/cost tolerance:
- High value transactions: Use rollup mode (full security)
- High frequency, low value: Use validium mode (lower fees)
StarkWare’s Volition
StarkWare designed Volition for their Starknet ecosystem:
- Single ZK-STARK proof covers transactions in both modes
- Users can even switch modes between transactions
- Applications (e.g., a game vs. a DEX) can set default modes for their users
Why Volition Matters
DeFi has very different security requirements by use case:
- Trading $1M in ETH: Rollup mode — full Ethereum security
- Playing a blockchain game: Validium mode — cheap, fast, DAC OK
- NFT marketplace: Depends on user preference
Volition is the architectural answer to “one size doesn’t fit all” in Layer 2 security models.
Sources
- StarkWare Volition post: starkware.co/volition
- Ethereum research: ethresear.ch
- Delphi Digital Layer 2 taxonomy