zkML: Evolving the Intelligence of Smart Contracts Through Zero-Knowledge Cryptography
Published: 2023-06-11 20:14:39

## Introduction:
Machine learning (ML) has become a powerful tool in various domains, but its integration with smart contracts has been limited due to computational challenges. However, the emergence of zkML (zero-knowledge machine learning) is set to change this landscape. By leveraging zero-knowledge cryptography, zkML enables the verification of ML model inferences on the blockchain, opening up new possibilities for autonomous and intelligent smart contracts. In this article, we will explore the potential applications, challenges, and emerging projects in the field of zkML.

## Enhancing Smart Contracts with ML:

Smart contracts, which are self-executing agreements with predefined rules, have revolutionized decentralized applications (dApps) and blockchain-based systems. However, they often rely on static rules and lack the ability to adapt to real-time data. By integrating ML capabilities, smart contracts can become more autonomous and dynamic, making decisions based on real-time on-chain data. This evolution enables increased automation, accuracy, efficiency, and flexibility in smart contract execution.

## The Challenges of On-Chain ML:
One of the main obstacles to incorporating ML models into smart contracts is the high computational cost of running these models on-chain. The resource-intensive nature of ML computations, such as training and inference, makes it infeasible to directly execute them on the Ethereum Virtual Machine (EVM) or similar blockchain platforms. However, the focus of zkML is primarily on the inference phase of ML models, which is more amenable to verification using zero-knowledge proofs.

## zkSNARKs: Enabling zkML:
Zero-knowledge Succinct Non-Interactive Arguments of Knowledge (zkSNARKs) provide a solution to the computational complexity of running ML models on-chain. With zkSNARKs, anyone can run an ML model off-chain, generate a verifiable proof of the model's inference, and publish it on-chain. This approach allows smart contracts to leverage the intelligence of ML models without directly executing them on the blockchain.

## Applications and Opportunities:
zkML opens up a wide range of applications and opportunities across various domains. In the decentralized finance (DeFi) space, verifiable off-chain ML oracles can be used to settle real-world prediction markets, insurance protocols, and more. ML-parameterized DeFi applications can automate lending protocols and update parameters in real-time. zkML also offers solutions for fraud monitoring, decentralized prompt marketplaces for generative AI, identity management, web3 social media filtering, and personalized advertising, among others.

## Emerging Projects and Infrastructure:
The zkML ecosystem is rapidly evolving, with several projects and infrastructure components emerging to support its development. Model-to-proof compilers, such as EZKL, circomlib-ml, LinearA's Tachikoma and Uchikoma, and zkml, enable the translation of ML models into verifiable computational circuits. Generalized proving systems like Halo2 and Plonky2 provide the necessary tools to handle non-linearities in ML models through lookup tables and custom gates. These advancements pave the way for the integration of zkML into various applications and use cases.

## Conclusion:
zkML represents a significant advancement in the integration of ML with smart contracts and blockchain-based systems. By leveraging zero-knowledge cryptography and zkSNARKs, zkML enables the verification of ML model inferences on-chain, enhancing the intelligence and flexibility of smart contracts. The potential applications and opportunities for zkML span across DeFi, security, traditional ML, identity, web3 social, and the creator economy. As the zkML ecosystem continues to grow and mature, we can expect further innovations and real-world implementations that harness the power of ML in decentralized systems.