Launching zkBridge Mainnet Alpha
We are thrilled to unveil zkBridge Mainnet Alpha release on zkBridge.com, now available for cross-chain interoperability on the mainnet of various layer-1 and layer-2 blockchain networks such as BNB Chain, Ethereum, and Arbitrum.
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Following a six-month testnet deployment and ongoing technical improvements, zkBridge is now live on zkBridge.com for the mainnet of various layer-1 and layer-2 blockchain networks such as BNB Chain, Ethereum, and Arbitrum. We extend our heartfelt thanks to our community for their participation and support, our partners for their backing, and our team for their dedication. Throughout the testnet phase, more than 100,000 users have participated in the zkBridge testnet, providing valuable feedback for the development of zkBridge.
During the mainnet alpha phase, users can use the zkBridge NFT and zkBridge Messenger on 10 layer-1 and layer-2 blockchain networks. We have also prepared exquisite NFTs for users to facilitate testing. We will also launch the zkBridge Loyalty Point Program powered by Galxe, to record each user’s participation on both zkBridge testnet and Mainnet Alpha. As users engage with zkBridge’s cross-chain product and interact with the social media and community, users will earn loyalty points that can be used to access future rewards. The participation of early users on our zkBridge testnet has been recorded through snapshots, and they will receive considerable loyalty points upon the launch of the zkBridge Loyalty Point Program.
For developers, they can start building cross-chain applications on zkBridge by visiting developer.zkbridge.com, and reviewing the related technical documentation at docs.zkbridge.com. If you want to become a partner of zkBridge, please fill in the application form to join the zkBridge ecosystem.
Introducing zkBridge protocol
zkBridge is the first trustless, efficient, secure, and universal cross-chain bridge with advanced zero-knowledge proof technology. zkBridge uses zkSNARKs to enable a prover to efficiently convince the receiver chain that a certain state transition happened on the sender chain. zkBridge consists of a block header relay network and an updater contract.
The block header relay network retrieves the block headers from the sender chain, generates proofs of the validity of the block headers, and sends the headers along with the proofs to the updater contract (set up on the receiver chain).
The updater contract maintains a light-client state. It automatically adds block headers of the sender chain once the associated proofs are verified, and updates the current main chain of the sender chain.
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Efficient zero-knowledge proof system
In zkBridge, we use a 2-layer recursive proof system to achieve fast proof generation and low on-chain proof verification cost to support cross-chain applications.
In the first layer, we present deVirgo, a distributed version of the Virgo proof system. deVirgo combines distributed sumcheck and distributed polynomial commitment to achieve optimal parallelism, and is able to accelerate the proof generation by orders of magnitude when running on distributed machines.
In the second layer, we use Groth16 to prove that the previously generated proof by deVirgo proves the corresponding block headers, significantly reducing on-chain verification gas cost.
Advantages of zkBridge
There are quite a few cross-chain bridge projects deployed today. However, most of them need more efficiency and better security. Up until now, more than $1.8 billion has been stolen by attackers from cross-chain bridges. Compared with existing cross-chain bridge systems, we summarize the advantages of zkBridge as follows:
- Trustless and secure: zk-SNARKs prove the correctness of block headers on remote blockchains, eliminating external trust assumptions. zkBridge is secure when the connected blockchains and the underlying light-client protocols are secure, and at least one honest node is in the block header relay network.
- Efficient: We design and implement deVirgo proof system to significantly accelerate the proof generation of the block headers. The relayed messages can be quickly finalized as long as the proof is verified, supporting fast processing of remote blockchain information.
- Decentralized: zkBridge implements a decentralized proof generation network. Any node can freely join the network to relay the block headers, generate proofs, and claim the rewards.
- Extensible: Applications can retrieve verified block headers through the updater contract, perform application-specific functionality, and enable extensive applications on top of the zkBridge.
- Universal: The block header relay network and the proof scheme in zkBridge are universal for blockchains supporting light client protocols to synchronize the block headers.
Applications on the zkBridge
By employing a modular architecture, zkBridge empowers developers and users a broad range of applications and features, such as token bridging and swapping, message passing, as well as computational logic that works with state changes from multiple blockchain networks. Here are some example use cases:
Cross-chain data availability: zkBridge allows multiple blockchain networks to access, share, and verify data in a secure and efficient manner. This interoperability enhances the overall functionality and efficiency of the blockchain ecosystem with seamless communication, data transfers, and collaboration among the systems.
Cross-chain Defi protocols: zkBridge enables seamless multi-chain interoperability to increase liquidity, attract users, and improve collaborations between various blockchain ecosystems. Examples of cross-chain DeFi protocols include multi-chain decentralized exchanges, cross-chain lending platforms, and multi-chain asset management tools.
Multi-chain NFT and GameFi: zkBridge empowers creators, developers, and gamers to interact with diverse blockchain networks, unleashing unparalleled opportunities for virtual asset creation, ownership, and in-game economies, fostering a thriving and interoperable digital landscape.
With the launch of zkBridge Mainnet Alpha, a new era of interoperability begins with the power of zero-knowledge proofs. The secure, efficient, and decentralized nature of zkBridge promises to revolutionize how blockchains interoperate with each other, opening up opportunities for developers, users, and the entire blockchain and Web3 community.
As zkBridge continues to evolve and expand its capabilities, the zkBridge protocol is set to become an indispensable infrastructure for the blockchain ecosystem, facilitating seamless communication, increased liquidity, and enhanced collaboration between various blockchain networks. This advancement will foster the growth of new applications, including cross-chain DeFi protocols, multi-chain NFT projects, and GameFi innovations, enriching the digital landscape and driving further innovation.
We invite developers, users, and enthusiasts to join us in our journey to transform the blockchain ecosystem and realize the full potential of cross-chain interoperability. Together, we can shape the future of blockchain technology and create a more interoperable, efficient, and secure digital world.