The second-layer extension of Ethereum based on zero-knowledge proof (ZK-Rollup) has always been a highly anticipated faction in the Ethereum ecosystem. In theory, it can solve the problems of efficiency and security in a relatively balanced way.
Vitalik has repeatedly expressed his almost unreserved optimism about this technology in his articles and public speeches.
However, unfortunately, in terms of specific implementation, it is subject to the limitations of current engineering technology. Zero-knowledge proof requires a lot of computing power and it is difficult to complete complex calculations in a short period of time. This makes it difficult to compete with the OP faction in terms of application, and the gap between the two is still widening.
This gap is particularly obvious in terms of ecological construction. According to the latest data on L2Beat (https://l2beat.com/scaling/tvl), the TVL of the four ZK systems, Stark, zkSync, Linea and Scroll, is not as high as that of the third-ranked OP system Base (Arbitrum and Optimism rank first and second respectively).
Despite this, capital's enthusiasm for the ZK system seems to have never diminished. Recently, A16Z released its own open source platform ZKVM.
It should be noted that: Unlike the ZKEVM we often hear, ZKVM has one less letter, but the meaning is obviously different. ZKEVM emphasizes compatibility with the Ethereum virtual machine, while ZKVM is a broader virtual machine platform. In theory, ZKVM has a wider range of applications.
As far as I can remember, this is the first time that A16Z has personally laid out the development of the track in the crypto track.
A16Z's actions, Vitalik's arguments and the technical and theoretical advantages of the ZK system all remind us that we must keep an eye on the development of the ZK-based second-layer extension system.
However, the development of several leading ZK-based second-layer extension systems is really unsatisfactory, while another rising star Metis is worthy of attention in some aspects.
Metis is also an Ethereum second-layer extension based on zero-knowledge proof. But unlike other "purebred" ZK-based extensions, it uses a hybrid system, with some transactions processed by OP and the other transactions processed by ZK. This allows it to combine the advantages of both in terms of efficiency and performance.
However, to be realistic, due to the current technical limitations, this advantage is not particularly obvious at present.
In addition, its "self-revolution" in the sorter is more worthy of attention.
In Ethereum's Rollup second-layer expansion system, whether it is the OP system or the ZK system, they have one thing in common in terms of technology: that is, a sorter is required to sort transactions, package them, and finally send them to Ethereum for final confirmation.
At present, most of the second-layer expansion systems have adopted centralized sorters for the convenience and efficiency of implementation, or simply use servers for processing.
This centralized processing is an open "secret" in the industry, and even Vitalik has publicly criticized this problem. But no matter how everyone criticizes, the project parties are "loud thunder and small raindrops", saying that they want to decentralize as soon as possible, but they are slow to act on the other side.
Why?
Because the centralized sorter is too in line with the interests of the project parties.
But Metis boldly started a "self-revolution" and began to try to promote the decentralization of the sorter and took substantial actions.
According to its plan, in the future, as long as users are willing to pledge Metis tokens, they can participate in the sorting operation of transactions in the Metis system, just like staking in Ethereum.
This approach can also solve the problem of token empowerment in many second-layer expansion systems at present, allowing tokens to generate value.
More importantly, if the ZK-series sorter achieves decentralized operation, a new track may be derived in the future: zero-knowledge proof "mining" based on hardware computing power.
In this kind of "mining", each node in the second-layer expansion must strive to use the strongest computing power to calculate the zero-knowledge proof result as quickly as possible, and strong computing power requires the stacking of strong GPUs.
So once this development becomes a trend, it is very likely that new mining tracks will be born in the second-layer expansion of Ethereum and even in all fields that require zero-knowledge proof computing.
Of course, whether it can develop depends on whether the project party attaches equal importance to ecological construction in addition to technology, otherwise the future prospects are not optimistic.
However, these new trends that may change the ecological landscape are still worthy of our investors' attention.