OLA: Building Bitcoin Ecosystem Trust-minimized Bridge Core Infrastructure
Introduction to OLA
OLA is an infrastructure focused on cross-chain trusted interactions, providing inter-chain zero-knowledge proofs for the Bitcoin ecosystem. Traditional BTC cross-chain bridges often rely on multi-signature custody or centralized intermediaries, which impose additional trust assumptions on the security of user funds, typically controlled by a single entity or a majority of entities. This model introduces centralized risks and deviates from the decentralized spirit of Bitcoin. In contrast, OLA aims to minimize reliance on third parties for cross-chain bridges through cryptographic methods and decentralized mechanisms.
With the gradual improvement of the BitVM2 protocol engineering practice, the Trust-minimized Bridge built on BitVM2 has become an important infrastructure for various Bitcoin projects. The construction of the Bitcoin Trust-minimized Bridge requires several core foundational modules:
- Bitcoin Verifier script splitting
- Target Chain Block Header ZKP
- A sufficiently large BitVM2 Challenger network
OLA focuses on building a full-chain Block Header ZKP generation management platform, providing verifiable chain state proofs for various projects' Trust-minimized Bridges, ensuring the credibility of state synchronization between different chains. Its goal is to establish an interaction channel with minimal trust assumptions between Bitcoin and other blockchains, achieving cross-chain bridging infrastructure without custodians. Through the chain state proofs provided by OLA, cross-chain bridges based on the BitVM2 protocol can verify state changes on the Bitcoin main chain and target chains without trusting intermediaries, thus safely executing cross-chain operations such as Peg-In (anchoring deposits) and Peg-Out (redeeming withdrawals). It is worth emphasizing that this design allows the cross-chain flow of Bitcoin assets to no longer rely on centralized custody or federated multi-signatures, but instead ensures security through zero-knowledge proofs and decentralized verification networks. OLA hopes to become the native cross-chain connection base for Bitcoin, extending its security to a multi-chain environment and reducing trust costs in cross-chain interactions.
OLA Technical Architecture and Module Description
The OLA system consists of multiple modules working in coordination, each performing its role to achieve the generation, verification, and submission of inter-chain state proofs. The main architectural modules include:
- OLA Control HQ: Responsible for the management and orchestration of all modules in the OLA network, serving as the core for task scheduling and external RPC services. Control HQ coordinates the proof generation, verification, and submission processes, ensuring that each component operates in sequence and provides interfaces for developers and other chains to call and query chain proof services.
- Myriad Chain Prover: A multi-chain proof generation module. This module generates proofs of block header hash validity (i.e., "chain proofs") for multiple blockchains using zero-knowledge proof technology. It verifies that the block header chains of each chain comply with consensus rules (e.g., the hash difficulty and linking relationships of proof-of-work chains), outputting verifiable validity proofs. It is important to note that Myriad Chain Prover does not directly generate proofs of specific transaction inclusions but focuses on the consistency proof of the entire chain state. This design reduces the computational complexity of proofs, focusing on providing a credible snapshot of each chain's state, thereby providing foundational trust for cross-chain interactions.
- Onis: A zkRollup that uses Bitcoin as the settlement layer, serving as OLA's decentralized verification and zk proof management module. Onis acts as a trustless light node for each chain, responsible for receiving and storing chain state proofs from Myriad Chain Prover and verifying the validity of these proofs on-chain. Essentially, Onis serves as a validator for multiple chains and the DA layer for chain proofs: through zero-knowledge proof technology, Onis can establish secure connections between Bitcoin and other blockchains, enabling seamless asset and data flow across multiple chains. For cross-chain bridges, Onis plays the role of the on-chain state verification contract for the target chain, updating its internal state root once a new state from a chain is verified, thus maintaining the synchronization of multiple chain states. Since Onis is a zkRollup with Bitcoin as the settlement layer, it ensures security while maintaining efficiency, achieving a balance between security and efficiency in cross-chain interactions.
- DMN (Decentralized Massive Network): A verification and supervision network composed of a large number of decentralized users, Massive, which is the cornerstone of OLA's security model. DMN includes multiple sub-networks or roles that work together to ensure the reliability of chain proofs and the cross-chain process:
- MVN (Massive Verifier Network): A large network of nodes responsible for independently verifying the chain proofs submitted by Myriad Chain Prover. Any generated zero-knowledge proof of chain state will be reviewed by numerous verification nodes in the MVN to ensure the correctness of the proof. Only when the chain proof is confirmed by a sufficient number of verifiers (reaching a preset verification threshold) will Onis's contract accept the proof. This multi-node verification mechanism further reduces trust risks, and the widespread verifiers provide additional security guarantees for the network while sharing the profits generated during the cross-chain process.
- MBSN (Massive Bitcoin Supervisor Network): Acts as a supervisor during the BitVM Peg-In process. Peg-In refers to the process where users lock BTC on the Bitcoin main chain, and MBSN nodes are responsible for monitoring whether the light client regarding the Bitcoin locking status on the target chain is consistent with the Bitcoin mainnet. In other words, when users lock BTC on the Bitcoin main chain, the target chain (such as Ethereum or other chains) will receive corresponding Bitcoin block headers and transaction proofs; MBSN verifies whether these on-chain states genuinely reflect the situation of the Bitcoin main chain, preventing the target chain from accepting forged Bitcoin block information. Through distributed supervision and initiating the SuperBlock challenge process on the target chain when necessary, MBSN can ensure the consistency and validity of the data transmitted across chains during the Peg-In phase.
- MBCN (Massive Bitcoin Challenger Network): Acts as a challenger during the BitVM Peg-Out process. Peg-Out refers to the process where users burn anchored assets on the target chain to retrieve Bitcoin. MBCN nodes closely monitor the unlocking requests for these locked BTC on the Bitcoin main chain. When someone attempts to illegally unlock BTC without valid cross-chain proof, MBCN will immediately detect this and trigger the challenge mechanism on the Bitcoin mainnet. Specifically, the BitVM2 protocol on the Bitcoin main chain sets a challenge window, during which MBCN can submit fraud evidence to prove that a Peg-Out unlocking request is illegitimate, thereby preventing improper fund unlocking. Through this challenge network, even if individual links exhibit malicious behavior, the system can still ensure the security of the cross-chain bridge based on the assumption of "at least one honest challenger."
The above modules work together to achieve a cross-chain bridge infrastructure that is minimally trusted and capable of verifying states across multiple blockchains. OLA extends Bitcoin's security model to inter-chain interactions: funds are hosted by smart contracts and BitVM2 scripts, combined with the supervision of multiple verifiers, allowing the cross-chain bridge to operate securely with minimal trust assumptions (such as 1-of-N participants being honest).
Overview of OLA Technical Process
To ensure the credible synchronization of multi-chain states, OLA has built a mechanism for the transmission of inter-chain proofs and state verification, covering the generation, submission, verification of chain state proofs, as well as supervision and challenges during cross-chain operations:
- Chain Proof Submission and Verification: When Myriad Chain Prover generates a new zero-knowledge proof of blockchain state for a certain chain, this proof will be submitted to the Onis network. Subsequently, numerous MVN verification nodes will parallelly verify this proof. Each verifier independently runs a zero-knowledge proof verifier program to confirm that the proof indeed validates the corresponding chain's block header hash sequence as valid and extends to the latest height. Once a sufficient number of verifiers report the proof as valid, reaching the system's preset verification threshold, the MVN will submit this result to the Onis contract on-chain. After Onis's contract receives a sufficient number of verification signatures or statistics, it will verify the proof on-chain, and upon successful verification, the corresponding chain's new state root (e.g., the latest block header hash) will be recorded in Onis's state proof. The entire process achieves a flow of inter-chain state proof transmission: off-chain zero-knowledge proofs provide efficiency, decentralized majority verification provides security guarantees, and on-chain contracts ultimately anchor the state, ensuring that cross-chain state updates are both efficient and credible.
- Peg-In State Supervision (MBSN): During the user's initiation of Peg-In (cross-chain transferring BTC from the Bitcoin mainnet), MBSN nodes play a crucial supervisory role. When users lock Bitcoin in the BitVM2 protocol script on the Bitcoin main chain, the corresponding locking event needs to be recognized by the target chain. Specifically, the target chain (which may be Onis Rollup or another cooperating chain) will run a Bitcoin light client module to track Bitcoin block headers and verify the Merkle proof of specific locking transactions. The MBSN network will monitor this process, verifying the correctness of the Bitcoin block headers and transaction proofs received by the target chain. If there is a discrepancy between the target chain's Bitcoin light client state and the actual Bitcoin chain (for example, if a malicious node provides incorrect block headers to the target chain contract), MBSN can detect this and initiate a challenge process. Under normal circumstances, a sufficient number of MBSN verifications will assure the target chain that the Bitcoin locking has indeed occurred, thus triggering the minting of corresponding anchored assets (such as Peg-BTC) on the target chain. Through MBSN's supervision, the inter-chain state transmission during the Peg-In process maintains high integrity, ensuring that the locking status of the Bitcoin main chain is accurately reflected in the cross-chain system.
- Peg-Out Challenge Mechanism (MBCN): Peg-Out is the process where users destroy anchored tokens on the target chain to redeem Bitcoin. Since the Bitcoin main chain ultimately executes the unlocking of BTC, it is crucial to ensure that only legitimate redemption requests can unlock BTC to the correct address. To this end, BitVM2 bridge scripts are typically designed with a delayed unlocking (exit) mechanism, setting a challenge period after the user initiates a redemption request. During this window, MBCN nodes will review the corresponding cross-chain proofs and transactions: checking that the user has indeed burned an equivalent amount of Peg-BTC on the target chain and that the Peg-Out request complies with protocol rules. If someone attempts to bypass the normal process by forging proof to directly request unlocking from the Bitcoin contract, MBCN will immediately initiate a challenge. The challenge includes submitting fraud evidence (for example, proving that the user did not burn tokens on the target chain or providing contradictory chain states), triggering the BitVM2 protocol to reject this unlocking and confiscate the violating party's deposit. This challenge mechanism operates under an optimistic assumption: assuming that at least one of the many observers is honest, it can prevent illegal withdrawal actions. Therefore, MBCN ensures that there are enough challengers online to supervise the validity of transactions during the Peg-Out phase, further reinforcing the security of the cross-chain bridge's trust model.
- Multi-Chain State Synchronization (Onis): As the core module of zk light clients for each chain, Onis is responsible for maintaining the credible synchronization of multi-chain states. When a new state proof from a chain passes the verification threshold and is verified by the Onis contract, Onis updates its state record regarding that chain (e.g., the latest block hash or state root). Over time, the states of different chains will continuously be submitted and updated in Onis through the above process. Since each chain's updates are verified through zero-knowledge proofs and decentralized verification, the states stored on Onis can be regarded as a credible mirror of multi-chain states. In other words, Onis provides a trustless synchronized view for multiple blockchains: anyone or DApp can query Onis for the latest state of Bitcoin or other chains without having to run a full node or trust third-party data. This multi-chain synchronization capability means that the Bitcoin ecosystem can achieve state interoperability with other chains with the support of Onis. In summary, Onis utilizes zero-knowledge proofs to bring the consensus security of each chain into cross-chain scenarios, maintaining the consistency and reliability of multi-chain states.
Through the above mechanisms, OLA achieves a closed-loop process for cross-chain states from proof generation to verification acceptance and state synchronization. In this process, no centralized entity can unilaterally tamper with cross-chain states: only valid on-chain proofs recognized by a majority of verifiers can take effect on the target chain. Meanwhile, during the flow of cross-chain assets, the supervisor network and challenger network continuously ensure the honest conduct of the process. Once anomalies are detected, the system can respond promptly, ensuring the consistency of the final state and the safety of funds. This design establishes a connection between Bitcoin and other chains based on cryptographic proofs and decentralized consensus, achieving a truly minimally trusted cross-chain bridge.
Progress and Launch Plan for OLA Mainnet
The development and deployment of OLA project modules are progressing according to plan, with significant milestones achieved:
- OLA Control HQ: The development of this central module has been completed, achieving unified scheduling of various verification and proof modules and external interfaces. Control HQ is currently operating stably, providing task orchestration and RPC service support for the testnet and developers.
- Onis Testnet: The Onis testnet version has been developed and deployed. Developers and partners can verify Onis's functionality for multi-chain state synchronization and verification through the testnet, simulating cross-chain operation processes between Bitcoin and other chains. The launch of the testnet marks the entry of OLA's core functionalities into the testing phase.
- MVN (Massive Verifier Network): The Massive Verifier Network has been operating stably for nearly a year. As of now, over 235,000 verifiers from more than 180 regions worldwide have participated, generating approximately 874 million verification results. This vast mobile ZKP verification network provides a solid decentralized verification foundation for OLA, demonstrating its scalability and security in practical operations.
- MBSN and MBCN: The core module development of the two Bitcoin supervision/challenger sub-networks has also been completed. Currently, these two modules are undergoing joint debugging and integration with Bitcoin-related project parties. In other words, OLA is collaborating with other teams in the Bitcoin ecosystem to test the light client interactions and challenge mechanisms in the Peg-In/Peg-Out processes, ensuring that MBSN and MBCN can seamlessly integrate into actual cross-chain bridge applications. Once integration is complete, these networks will officially take on supervisory and challenging responsibilities, further improving the security closed loop of the OLA cross-chain bridge.
- Myriad Chain Prover: As a key module providing zero-knowledge chain proofs for OLA, Myriad Chain Prover is currently in accelerated development. The development team is tackling ZK circuit optimization and performance tuning for multi-chain block header verification, planning to complete the development of its core functionalities in the second quarter. At that time, OLA will be capable of producing efficient chain state proofs for multiple chains, preparing for mainnet deployment.
- Mainnet Launch Plan: According to the project roadmap, the mainnet versions of all OLA modules (including Control HQ, Onis, Myriad Chain Prover, and various sub-modules of the Massive network) are expected to launch in the third quarter. After the mainnet launch, OLA will be open for use by a wide range of users and developers, realizing the genuine value connection between Bitcoin and the multi-chain ecosystem. Before the mainnet launch, the team will continue to conduct security audits, performance testing, and multi-party debugging to ensure that the cross-chain bridge infrastructure launched is sufficiently secure and robust.
Through these milestone advancements, OLA is gradually transitioning from conceptual design to practical deployment. The data from the testnet and the long-term operation of the Massive verification network provide strong support for the mainnet, instilling confidence in the upcoming mainnet phase.
Summary and Outlook
OLA innovatively combines cryptography and decentralized networks to bring structural improvements to cross-chain trust capabilities within the Bitcoin ecosystem. Leveraging zero-knowledge proof technology and the BitVM2 protocol fundamentally changes the security model of cross-chain interactions. The participation of numerous distributed verifiers and supervisors endows the system with strong resistance to censorship and fraud, truly realizing the design intent of "minimized trust."
This native cross-chain connection base has far-reaching significance: first, it allows Bitcoin assets to flow freely and securely in a multi-chain world. Users will be able to use BTC on smart contract platforms like Ethereum to participate in DeFi, NFT trading, and other innovative applications without worrying about custody risks and trust barriers. This will unlock the immense value that Bitcoin has long been accumulating, empowering BTC with more diverse application scenarios. Secondly, the emergence of OLA provides a scalable and universal infrastructure for cross-chain bridges. In the future, any blockchain wishing to interact with Bitcoin can integrate the chain proofs and state synchronization services provided by OLA, enabling the rapid construction of secure cross-chain bridges without reinventing the wheel. In this way, OLA will promote the true integration of Bitcoin into the multi-chain ecosystem, becoming the value hub between chains.
In the long run, OLA is committed to becoming a decentralized trust bridge for the Bitcoin ecosystem, connecting Bitcoin assets worth trillions of dollars with a rich variety of blockchain applications. With the mainnet launch and ecosystem expansion, more and more users and project parties will participate in the OLA network, jointly verifying and witnessing each state update of cross-chain interactions. Bitcoin will no longer be an island but will achieve interconnectivity with other networks through OLA's bridge while maintaining its own security. Such interoperability will greatly enhance Bitcoin's capital efficiency and application potential, bringing new opportunities for decentralized finance and Web3.
In summary, OLA is not just building a cross-chain bridge application but a foundational trust layer. It uses cryptography as a shield and community networks as a cornerstone, providing unprecedented security guarantees and freedom for Bitcoin cross-chain interactions. Through OLA, the value of Bitcoin can flow seamlessly in the multi-chain ecosystem, and innovations across chains can absorb the liquidity and security of Bitcoin. This virtuous cycle will promote the integrated development of the entire blockchain industry. Our outlook for OLA is that as technology matures and adoption expands, it will become a key pillar for Bitcoin's journey into a multi-chain future, allowing the most original and trustworthy crypto asset to thrive with renewed vitality in the new era.