zk-Hybrid： A Zero-Knowledge (zk) VM based on MIPS Architecture
In the plan at the beginning of the month, we have already announced that we will start building an advanced ZK proof solution dominated by ZK-rollups that links the advantages of optimistic rollups and zk-rollups. We call it zk-Hybrid.
Blockchain technology has played a key role in the development of zero-knowledge proofs (ZKP). As a result, ZKP has been widely adopted in the blockchain space to enhance privacy and scalability. However, ZKP’s potential extends far beyond the blockchain realm. In the modern context, ZKP holds great promise in revolutionizing areas as diverse as the Internet of Things (IoT) and Virtual Reality (VR). XpansionChain is also a Layer 2 smart expansion chain using ZK-rollups as an Ethereum solution.
Previously, we also took you to understand the principles and advantages of optimistic rollups, another solution of Ethereum. If you forget, you can check it out:
This article will be more comprehensive:
Next we will introduce zk-Hybrid in detail.
zk-Hybrid
zk-Hybrid leverages the MIPS instruction set to build efficient ZK VMs. zk-Hybrid contains a VM capable of executing MIPS programs and interacting with the execution environment, demonstrating its compatibility with different platforms. zk-Hybrid converts Ethereum Geth to the MIPS instruction set and uses its VM to execute the resulting program.
Proof generation
zk-Hybrid uses state-of-the-art mechanisms such as Starky and Plonky2 to generate ZK proofs for resulting execution traces. An outlined version of this architecture can be found in the paper, and the proof-generating architecture looks like this:
Proof size and prover time
The goal is to design a ZKP system that both achieves shorter proof sizes, ensures minimal data overhead, and reduces prover time to speed up transaction processing. While confirming other performance metrics such as maximum memory usage, CPU usage, and number of constraints, XpansionChain’s zk-Hybrid works to optimize these key aspects to create an efficient and scalable solution. The zk-Hybrid proof generation process strikes a balance between proof size and proof time by applying combinatorial and recursive steps to generate shorter proofs obtained within a specific time based on the requirements of the target application.
