In the world of Layer 2’s, there are a lot of new technologies that all try to solve the same problem with Ethereum: scalability. There are four better known technologies that each have a different approach and software type: ZK Rollups, Optimistic Rollups, Plasma, and Validiums.
Validiums are most like JK-Rollups but differ in a couple ways. Read more about ZK-Rollups here. Here are the basics, a rollup is a technology in layer 2’s that takes the transaction off chain from Ethereum (layer 1) to lower the gas fee cost and speed up the transaction.
Validiums are zk rollups but instead of having the data availability on chain, validium keeps it off chain. This allows validiums on Ethereum to achieve a transactions per second rate of 9,000 or more. Both are rollups and provide a separate layer for transactions to scale bigger chains, but Validity does it in a way that keeps it theft-proof. Data from the transactions is verified and stored off-chain and offline, which can be a downside if the main chain has no data interaction for a long period of time.
Validium seeks to increase security and speed while decreasing the cost of Ethereum.
