At the ETH forum for developers, Vitalik Buterin said that Ethereum can borrow the technological innovations of the confidential-oriented Zcash cryptocurrency for the "mass verification" of ETH transactions.
ZK-SNARKS allows to relay nodes, significantly compressing the amount of data stored in the blockchain. According to the estimates of the Ethereum co-founder, the integration and implementation of ZK-SNARKS can allow Ethereum to process up to 500 transactions per second. Compared to the current limit of about 15, it not only allows to increase the network capacity by 3200 percent, but also to achieve, along with Plasma and other solutions for scaling the second level, such opportunities that increase the network bandwidth, moving most transactions from the main blockchain subject to the preservation of the security.
When used in tandem with technologies of the second level, the improvement in scaling would be even more pronounced. For example, the implementation of Plasma, presented by Matter, will allow Ethereum to reach 25,000 TPS. And the set of all implementations, including sharding, can "speed up" the ETH network to several million transactions per second.