The past few weeks have seen a wave of zero-knowledge proof project launches, including Polygon’s zkEVM and Matter Lab’s zkSync Era on m
The past few weeks have seen a wave of zero-knowledge proof project launches, including Polygon’s zkEVM and Matter Lab’s zkSync Era on mainnet, and the Linea zkEVM from ConsenSys on testnet.
They join StarkWare’s long-running StarkEx solution and its decentralized cousin StarkNet along with a variety of other projects in development from Polygon (Miden, Zero, etc.) and Scroll.
They all promise faster and cheaper transactions to scale Ethereum using zero-knowledge proofs.
But is the brutal competition between ZK-rollups a zero-sum game where there can be only one winner? Or are we looking at a future in which lots of different rollups are able to work in harmony and interoperably?
Anthony Rose, head of engineering for zkSync, thinks the latter future is much more likely and predicts that one day, no one will think about which ZK-rollup they are on because it’ll all just be infrastructure.
“I think that if we don’t get to that world, then we’ve probably failed,” he says. “It’s the same way as somebody using Snapchat or Facebook doesn’t really have to know about TCP/IP or HTTP — it’s just the plumbing of the way the internet works.”
But how do we move from a bunch of competing sovereign rollups to an ecosystem of ZK solutions that are interoperable and composable?
People are already starting to think about this question, and all of the ZK projects Magazine spoke to have plans to make their projects interoperable with at least some other rollups — although the extent to which that can happen likely depends on the development of standards and protocols.
Also read: Attack of the zkEVMs! Crypto’s 10x moment
Zero knowledge about ZK-rollups?
If you’re unfamiliar with the term “zero-knowledge proofs” — which StarkWare insists should be called “validity proofs” — they’re a way to scale Ethereum using cryptography. Rollups take the computation for tens of thousands of transactions off the main blockchain and write a tiny cryptographic proof back to Ethereum that proves the computation was carried out correctly.
“Every proof we generate covers roughly 20,000 transactions and fits inside a single block of Ethereum,” explains StarkWare co-founder Eli Ben-Sasson.
Despite this increase in transactions per block, zkSync’s Rose doesn’t think Ethereum can come close to scaling up to become the base layer for everything via a single rollup.
“A ZK-rollup on its own will not scale to the world that we’re talking about,” Rose says. “If we think that applications with some interactions on the blockchain are providing value to hundreds of millions of people, the scalability problem is still there to be solved.”
Scaling is a little like internet bandwidth, in that the more you get, the more you realize you need. Back in 2017, Ethereum planned to scale using “Eth2” sharding. This roadmap was then ripped up after ZK-rollups emerged in 2018 and promised vastly greater scaling, but only if Ethereum upgraded the blockchain with a different form of sharding (proto danksharding and then danksharding) to enable the ZK-rollups to achieve higher throughput.
Even then, Rose says it’s likely rollups will need to work in collaboration. “This is a big active area of research for us,” Rose says of interoperability. “As the systems mature as well… I think, naturally, this is kind of the pattern that these systems suggest.”
Ethereum scaling is some way off
It’s the early days yet for scaling, however. Although various solutions claim they can theoretically hit tens of thousands of transactions per second (or even talk about “unlimited” scaling), in practice, they’re hamstrung by data availability on Ethereum.
At present, between them, the various Ethereum scaling solutions and Ethereum are running at about 25 transactions per second (TPS). Ethereum itself has performed an average of about 12 TPS over the past month, Arbitrum One was at 7.2 TPS, Optimism at 2.65 TPS and zkSync at 1.6 TPS, according to ETHTPS.info.
These numbers move around a bit and are low mostly due to demand rather than capacity. StarkEx is not covered, but StarkWare tells Magazine it averaged 5 TPS over the past month.
Despite supply outweighing demand so far, interoperability between rollups would already be helpful to ensure that users don’t get stuck in walled gardens. Optimistic Rollup users, for example, have to wait a week to withdraw funds, which rather limits interoperability.
ZK-rollups don’t have that limitation and can allow instant withdrawals (but don’t).
Also read: ZK-rollups are ‘the endgame’ for scaling blockchains: Polygon Miden founder
Interoperable ZK-rollups are possible, but is it probable?
Bobbin Threadbare, founder of Polygon Miden,…
cointelegraph.com