GOAT Network reshapes Bitcoin's second layer, zkMIPS ecosystem welcomes new breakthroughs

The Bitcoin Layer 2 network is a technological solution aimed at improving the speed of Bitcoin transactions. By moving a portion of transactions off the Bitcoin main chain to be processed off-chain, it alleviates the burden on the main chain, enhances transaction processing speed, and reduces transaction costs. Common Layer 2 network technologies include the Lightning Network, State Channels, and the currently popular BitVM2 bridge combined with zkRollup.

Challenges Facing Bitcoin Layer 2 zkRollup Solutions

• Security: Security is the most concerning factor for Bitcoin holders. Security needs to consider the network's consistency, liveness, and self-healing. Consistency, or consensus security, determines the immutability of the entire network's ledger; liveness determines the overall network's availability; and self-healing determines how quickly the network can recover from attacks or anomalies. As a BTC zkRollup, to inherit BTC security, it is necessary for the zkRollup to fully commit to Layer 2 transactions, and these commitments must be directly verifiable by Bitcoin miners. However, the challenge lies in the current difficulty of implementing Covenants in BTC scripts. Recently, some promising solutions have emerged, including BitVM2, function encryption, and the latest ColliderScript solution. Additionally, there is the challenge of maintaining the liveness and self-healing of the Layer 2 network itself. Many zkRollups currently face issues with centralized Sequencers, leading to a high degree of centralization within the Rollup chain, lacking sufficient incentives for other players to participate, creating a vicious cycle.
• Programmability: Programmability is the infrastructure of BTCFi. As the largest asset by market capitalization in the blockchain ecosystem, Bitcoin has long been viewed as a store of value, but it appears relatively lacking in practical applications and yield generation. This limitation primarily stems from the scalability of the Bitcoin network and the inherent restrictions of its scripting language, making it difficult to support complex decentralized finance (DeFi) applications. For Bitcoin holders, the traditional way to earn yields from their BTC holdings has been to deposit assets into centralized exchanges or use bridging services to convert them into wrapped tokens (such as WBTC). However, these methods introduce additional risks, such as trust risks associated with centralized platforms, which contradict the decentralized nature of Bitcoin. Drawing on the rich protocols and ecosystem of the ETH ecosystem in DeFi, introducing EVM becomes very important.

GOAT Network: An EVM-Compatible Bitcoin Layer 2 Network Based on zkMIPS

GOAT Network is the first optimistic challenge protocol that enhances security in Bitcoin Layer 2 based on zkMIPS, BitVM2, and decentralized Sequencers, achieving 100% EVM compatibility while only requiring a 1-of-n assumption to ensure the security of the Bitcoin network. GOAT Network has the following core highlights:

• Achieving True Decentralization: Through an innovative permissionless decentralized Sequencer protocol, all cross-chain messages—including asset peg-in, peg-out, and Layer 2 network state Rollup—can reach consensus on both Bitcoin and the GOAT Network. This completely eliminates reliance on a single centralized entity, ensuring true decentralization. At the same time, this innovation significantly simplifies the trust setup of the BitVM2 protocol while providing equivalent security guarantees.
• Comprehensive Verification of Bitcoin Without Forking: The GOAT Network combines decentralized Sequencers and the BitVM2 protocol, making the BitVM2 protocol practical by directly verifying proofs through Bitcoin scripts, inheriting Bitcoin's native security. zkMIPS serves as the scaling infrastructure for GOAT, achieving 100% EVM compatibility while significantly accelerating the proof generation and verification process, bringing unprecedented ecological expansion capabilities to the GOAT network.
• Dual Penalty Mechanism Ensuring Security: GOAT Network is the first to introduce a "dual penalty" mechanism in the Bitcoin Layer 2 network. This mechanism combines the native penalty mechanism of the Bitcoin validation layer with the penalty mechanism of the GOAT consensus layer, effectively reducing the probability of dishonest behavior within the GOAT Rollup protocol. This mechanism specifically addresses potential risks such as double signing, node downtime, and illegal reimbursement attacks on Sequencer nodes, comprehensively enhancing the network's security and reliability.

This technological innovation marks a new era of decentralization for Bitcoin Layer 2 networks, setting a new industry benchmark for the future of blockchain technology.

In the integration of zkMIPS with BitVM2, zkMIPS optimizes the Groth16 proof speed while also making significant optimizations in the verification phase, including using Hints techniques to significantly reduce the complexity of calculating the Miller Loop in Bitcoin scripts, segmenting the Verifier circuit for commitments, compressing zkVM's public input commitments, and leveraging Decentralized Sequencers to ensure that public inputs and superblocks are on the same branch, thereby simplifying the complexity of the BitVM2 optimistic challenge process to some extent.

zkMIPS: The First zkVM Based on the MIPS Instruction Set

zkMIPS is the first zkVM based on the MIPS instruction set, which is a mature instruction set with advantages including:

1. The instructions of MIPS32R2 are richer compared to RISCV32IM, with J/JAL series instructions allowing for jump lengths of up to 256MiB, making it very convenient to implement jumps in static linking scenarios. MIPS32r2 has a rich set of bit manipulation instructions that do not exist in RISCV32IM, requiring the use of B extensions. MIPS32r2 includes conditional select instructions like MOVN/MOVZ, which can replace jump instructions in many scenarios, improving performance and reducing the number of instructions. MIPS32r2 also includes integer multiply-accumulate instructions, enhancing performance and reducing instruction counts. MIPS32r2 has SEH and SEB sign extension instructions, making it very convenient for sign extension operations on char and short data types.
2. All instructions in MIPS32r2, as a whole, have been widely used for over 20 years, eliminating issues of inter-module compatibility; there are also no potential upheavals due to copyright disputes. As an instruction set for extension implementation rather than a whole implementation, there may be issues of mutual adaptation between extensions. Certain combinations of extensions may have incomplete or overly large issues. The MIPS instruction manual provides clearer and more detailed descriptions of instruction behaviors. In blockchain, MIPS has been successfully applied to the verification of Optimism's Fraud Proof, which is based on the MIPS VM.

zkMIPS has comprehensive functionality. Developers can prove any program written in widely used high-level languages such as Rust and Golang. zkMIPS provides a series of easy-to-use development toolkits, including ZKM Playground, ZKM-Project-Template, and ZKM Proof Network, helping projects and developers build their ZKP products with very low barriers to entry.

zkMIPS helps developers ensure the security of circuit logic. Developers can implement any application using the language they are most familiar with, without the need for zero-knowledge proof circuit audits. Unlike traditional ZKP development, zkMIPS strictly adheres to the MIPS32r2 instruction set, so if developers have already audited the business logic of the application, there is no need to audit the circuit again.

ZKM provides a proof network that helps developers and projects quickly generate proofs, supporting horizontal scalability, and enabling real-time proof generation. This allows developers and projects to build their decentralized Web3 applications with extremely high efficiency. Additionally, zkMIPS supports various extreme proof acceleration solutions such as Precompiles. Currently, on the zk project ethproofs.org, which is heavily supported by the Ethereum Foundation, ZKM has launched the first proof generator based on the MIPS instruction set, providing real-time proof for Ethereum mainnet blocks.

zkMIPS has industry-leading use cases, supporting multiple innovative zkVM-supported use cases, including Bitcoin L2 of GOAT Network and HybridRollup of Metis. It is also promoting the widespread adoption of zkVM technology in various industries such as zkLLM and zkIdentity. In the future, combined with the mature ecosystem of MIPS and ZKM's ZKP infrastructure, ZKM will continue to drive the widespread implementation and application of zkVM technology.