What is Volition?
Before we take a detailed look at Volition, if you haven't already, we suggest you take a look at our posts about Rollup and Validium.
Shortly, Volition is a hybrid system where zkRollup and Validium are synthesized. Even though Rollups provide more cost effective transactions compared to the Ethereum Mainnet, this may not be enough. For users who don't have a lot of funds, $1 can be considered a high transaction cost for Rollups. So, how can we lower the costs to cents? It is possible to do this with Validium. But for what cost? To understand that, first we have to compare and contrast zkRollups and Validium.
zkRollups, forms zkproofs on the Rollup chain by using the power of math and computation. After that, this proof and data of state changes which contain the account balances of the users get published on the mainnet. The fact that the data is on the Ethereum mainnet means Rollups share the the same security with the mainnet.
With Validium, just like a zkRollup, a proof is generated for the transactions on the rollup chain, however the data is not sent to the mainnet with the proofs. Instead, a third party secures this data. Usually in the model developed by projects this third party is a comitee. So this means, because the data on Validium is not on the Ethereum mainnet, Validium does not share the same level of security as Ethereum. The security risk you take will be based on how much you trust the comitee. The comitee cannot steal your funds however they can freeze them.
So, on one side, the security is maximized with onchain data, and on the other side the cost is minimized with offchain data. Volition brings these two systems together and provides the customers with the freedom to pick their desired method when carrying out an transactions. Let's dive in to this situation by taking a look at zkSync's Volition system zkSync 2.0.
In zkSync 2.0, the L2 state will be divided into 2 sides: zkRollup with on-chain data availability and zkPorter with off-chain data availability. The zkRollup data will exist on the Ethereum mainnet and therefore share the same level of security as the mainnet.
On the other hand, The state data on the zkPorter side is secured by a Pos - like system supported by a crypto economic model. The shareholders under the name Guardian promise data availability with the zkRollup tokens that they have locked. The Guardians must keep track of the data availability by signing blocks or else when there is a failure of data usability will cause them to get slashed. The Guardians who do not want to lose the tokens that they have locked often show a tendency to dont make mistakes or commit fraud. This crypto economic model is of course still vulnerable to attack. The attacker who holds the 2/3 of zkSync tokens might stop producing block but they cannot steal the funds. This is because the Guardians are fundamentally powerless.
The accounts and the contracts on both zkRollup and zkPorter can interact with the accounts and contracts on the other side. The only difference that is noticable by the user is that the zkPorter side is almost a 100 times cheaper. It should not be forgotten that this model is designed by zkSync and that StarkNet is also working on a fundamentally similar yet different model.
Conclusion:
Volution systems, while solving the scalability, leaves the choice upto the users. This way those user who are sensitive about security and those who are sensitive about transaction costs can be in the same system. zkRollup projects believe that the future is hybrid systems such as Volition hence they continue the developments on this side. What about you? Which is more important: security or low transaction costs?
That’s all from L2 Planet for now, hope to see you in other issues :)