A way of proving the validity of a statement without revealing the statement itself
Zero-knowledge rollup has emerged as an efficient solution to tackle blockchain scalability challenges. This approach not only boosts network performance, but also brings down costs by alleviating the burden on the main blockchain. Explore this transformative technology further and discover which blockchains are innovating zero-knowledge proofs.
Content
- What is zero-knowledge?
- How do zero-knowledge proofs address blockchain scalability?
- Zk-rollup vs. optimistic rollup
- Types of zero-knowledge proofs: SNARK vs. STARK
- Blockchains that leverage zk-rollups
- Learn more about Layer-2 solutions
What is zero-knowledge?
Zero-knowledge proofs (ZKPs) are maintream cryptographic techniques. It allows one party (the prover) to demonstrate to another party (the verifier) that a statement is true without revealing any specific information about the statement itself.
In simple words, it proves a fact or solution to a problem without disclosing the actual content of that knowledge. ZKPs are essential for enhancing privacy, security, and efficiency in various fields.
In blockchain technology, zero-knowledge proofs are a foundational component of rollup solutions. They enable a more scalable, cost-effective, blockchain ecosystem, contributing to the continued growth and adoption of decentralized applications (dapps).
How do zero-knowledge proofs address blockchain scalability?
ZKPs address blockchain scalability by moving a substantial portion of transaction processing and computation off-chain. In this way, it reduces the workload on the main blockchain and provides a more efficient and cost-effective way to verify the correctness of transactions.
As Ethereum gains more widespread adoption and usage, the need for scalability enhancements becomes increasingly urgent. Techniques like ZKPs are adopted in Layer-2 solutions, becoming critical tools to address the growing demand for blockchain applications and services.
Zk-rollup vs. optimistic rollup
Zk-rollups bundle a set of transactions and process them off-chain. Then a cryptographic proof is generated to confirm their validity without revealing sensitive transaction data. This proof is then submitted to the main blockchain, where it’s checked and confirmed by the network. Zk-rollups prioritize security by providing strong cryptographic guarantees, making them suitable for applications requiring a high level of trust and privacy.
Optimistic rollups, on the other hand, is another Layer-2 scaling solution that also aims to address Ethereum’s scalability issues and lower transaction costs for users. Optimistic rollups also process transactions off-chain, similar to zk-rollups. However, instead of relying on cryptographic proofs, they operate on the assumption of transaction validity off-chain. This means transactions are initially assumed to be correct, and if any malicious behavior is detected, users can submit fraud proofs to challenge these transactions on the main blockchain.
While optimistic rollups offer excellent scalability and a more seamless user experience, they come with a trade-off in security compared to zk-rollups. There’s a brief window during which a fraudulent transaction might go through before being challenged. This makes them more suitable for applications where the risk of fraud is low and efficiency is crucial.
Types of zero-knowledge proofs: SNARK vs. STARK
SNARKs, or Succinct Non-Interactive Arguments of Knowledge, are a type of zero-knowledge proof known for their efficiency in producing concise proofs.
Notably, SNARKs require a trusted setup phase, where participants generate initial parameters, but this can raise concerns about parameter security. Once the setup is complete, SNARKs enable non-interactive proof generation, making them ideal for resource-limited blockchain environments. An example of a blockchain that uses SNARK is zkSync.
ZK-STARK, short for Zero-Knowledge Scalable Transparent Argument of Knowledge, shares similarities with ZK-SNARKs but has some differences. ZK-STARK is more transparent because it doesn’t need a special setup process. Additionally, it outperforms ZK-SNARKs when handling larger sets of data. An example of a blockchain that uses STARK is StarkNet.
Blockchains that leverage zk-rollups
zk-rollups are a promising technology for scaling blockchains. They offer a number of advantages over other scaling solutions. Blockchains that have employed zk-rollups include:
- Polygon
- Immutable zkEVM
- zkSync
- StarkNet (non-EVM-compatible)
You can explore the dapps running on these blockchains and access data about their performance by clicking on the links above.