Bridging the Multichain Universe with Zero Knowledge Proofs

And lastly we propose a two part standardized risk assessment framework that bridge users can use to guide themselves to choose the right bridge for their transaction requirements and level of security needed. Bridges present a challenge for blockchains since they need to be able to trust and validate external information. In order to facilitate the exchange of value between different blockchains, interoperability is essential.
This method allows for the efficient and cheap verification of Ed25519 signatures from the Cosmos SDK on the Ethereum blockchain without introducing any new trust assumptions. Electron Labs plans to solve this problem by creating a system based on a zkSNARK, which can generate a proof of signature validity off-chain and only verify the proof on the Ethereum chain. However, this approach is specific to the Ethereum 2.0 consensus protocol and the EVM and so may need to be more readily generalisable to be used on other chains. The evidence is created using off-chain computation, which includes constructing circuits to verify the validators and their signatures and then generating the SNARK proof. This process is computationally expensive, so the light client uses SNARKs to create a constant-size proof that can be efficiently verified on the Gnosis chain. Succinct Labs has developed a system that allows for a trust-minimised connection between Gnosis and Ethereum 2.0, a proof-of-stake consensus blockchain.

Oglądaj HBO Max już od 29,99 zł/mies.

The aggregator leverages Jupiter’s expertise in DEX technology and TON’s scalable infrastructure to optimize liquidity across the TON ecosystem. This ensures that the cross-chain bridging process doesn’t become a bottleneck, and the entire system remains scalable. These proofs are generated in a decentralized manner, ensuring no single entity has control over the entire process. While these methods achieved a degree of interoperability, they introduced trust issues, potential security vulnerabilities, and cumbersome processes. Token balances are aggregated using secure RPC endpoints.

Search code, repositories, users, issues, pull requests…

Zero-knowledge proofs are foundational to the privacy-preserving features of ZK-Port. This is typically in the case of transfer of funds where substantial trust assumptions are placed on the centralized bridging entity, which usually consists of a small number of trusted parties. Parallelism in proof generation via MPC spinmaya casino bonus brings its own bottlenecks in communication complexity, which are as yet open issues. The issues of computational overhead can be ameliorated using hardware acceleration, and the usage of SNARKS in particular, as well as tricks for committing public data, can reduce storage overhead.

2 What Is A Bridge?

The bridge design uses a relay network for generating zkp and has the least trust assumptions of all. The update contract is implemented in Solidity on Ethereum and keeps track of the Cosmos block headers, and the relay network’s Groth16 proof. The bridge consists of a relay network that fetches the Cosmos block headers and generates a deVirgo Proof for distributed proof generation. The main difference between the industry-led approaches and zkbridge is that the trust assumption is basically reduced to the existence of one honest node in the relay network, and that the zk-SNARK is sound. The updater contract verifies and either accepts or rejects proofs from nodes in the relay network.

Czym Max różni się od HBO Max?

By having a well-defined threat response plan, developers can help ensure that their blockchain bridges are able to recover quickly and efficiently from a hack and reduce the extent of the damage. In this case, if Doge-chain were to be compromised and the attacker wants to use the bridge to exit the funds, the bridge exposes all the liquidity providers of all chains to the hacker allowing them to drain the entire bridge. Threat mitigation is generally considered to be more important than threat response when it comes to hacks in blockchain bridges. The risk pillar that was compromised in this case was ‘Implementation Security’, as upgrading the base layer smart contract introduced a new bug, compromising the security of the bridge.

• By the end of Jan 2023, they ran a Snapshot proposal titled, “Temperature Check Which bridge should Uniswap v3 use for cross-chain governance messaging between Ethereum and BNB Chain?
• Unlike the other two industry-led ZKP bridge constructions, zkbridge is a framework on top of which several applications can be built.
• The relay network then submits the Groth16 proof to the updater contract that can verify it on-chain.
• Polygon PoS bridge (checking consensus of the Heimdall chain), Cosmos IBC (verifying signatures of another Cosmos chain) are great examples of this type.
• Natively verified bridges tend to rely deeply on the consensus of the underlying domain, which means you need unique implementations for each domain that the bridge is connecting.
• Additionally alternative Layer-1 blockchains were built with different consensus mechanisms, to tackle scalability and faster transaction throughput.

On June 23, 2022, the Horizon Bridge was targeted in an attack in which the perpetrators were able to access the assets bridged to the protocol by compromising at least two out of the four private keys used by the bridge validators. We can have two chains with completely different levels of economic security at the base layers, connected to each other. Externally verified bridge, you can have the same set of implementation logic as it is not tied to the consensus of any of the connecting domains, however you would need to have some complex off-chain coordination between all the validator sets. Natively verified bridges tend to rely deeply on the consensus of the underlying domain, which means you need unique implementations for each domain that the bridge is connecting. In a trustless system, the bonders are facilitating the crosschain messaging and fully collateralizing the funds by taking the risks on just themselves. Some checks and balances that can be implemented could be to have additional verification requirements for transactions that want to transfer over a certain % of bridge funds (such as 90% of the funds locked on the bridge).
Ultimately bridges were built between these parallel blockchains in order to ease fragmentation of liquidity and allow users to hop from one blockchain to another seamlessly. In the natively verified bridges, the trust was on the two blockchains. Notwithstanding the fact that this goes against the very founding principles of blockchains, it brings with it issues related to censorship and security.‍Some of the biggest hacks in blockchain history have occurred on bridges‍The main reason for security vulnerabilities are due to the way a bridge acts as a centralized storage unit. The Ethereum light client uses a solidity smart contract on the Gnosis chain, while the off-chain computations consist of constructing circom circuits for the verification of the validators and their BLS signatures, and then computing the zk-SNARK proof. Bridges are communication protocols that facilitate the transfer of information such as messages, funds or other data between blockchains. Hence, in order to safeguard the security and reliability of blockchain bridges, developers must implement proactive threat prevention strategies.
Without interoperability, the liquidity of assets is fragmented and the interconnectedness of different blockchains is limited. This report discusses the importance of interoperability for blockchain networks and the need for building bridges to facilitate the exchange of value between them. The deVirgo proof is then compressed using the Groth16 prover and verified by the updater contract on the target blockchain. The proof and block headers are then submitted to a smart contract on the Gnosis chain, which performs the verification. In the context of cross-chain bridging, this means enabling transactions and data to move between blockchains without revealing sensitive information. As we witness the rise of various blockchains, each with its unique features and capabilities, the need for a seamless connection between these networks becomes increasingly apparent.

zkbridge (Berkeley RDI)

• We can have two chains with completely different levels of economic security at the base layers, connected to each other.
• Joel John, a writer for Decentralised.co, who collaborated on this framework with the Socket team and has written a detailed piece titled ‘Assessing Blockchain Bridges’, expanding on each of these 5 categories.
• Now that we understand what a bridge is and why we need it, in the next section let’s uncover the different ways to categorize them.
• But when this is not possible, or very expensive to provide,, organisations may turn to trusted data providers, such as AWS or Infura, to access their needed data.
• The SGX application requires 6 of 8 Bridge Nodes to submit the same transaction before generating the signed transaction to process the Bridge transfer on the other network.

Since much of the bridge work is proving data-parallel circuits, a generalization of ZKP for parallelism like deVirgo are valuable directions for research. Following which, a Gnark adaptation of the optimized signature verification circuit (for out of field arithmetic) designed by Electron-labs generates the Groth16 proof in the second step of the recursion. The GKR multilayered sum-check protocol has a communication complexity of O(N log_2(gates per layer)) for N machines in the relay network. The main purpose of the recursion is to achieve succinctness (proof size) and reduce verification gas costs.

Hence there is a lot of research and development focussed on building this critical component in the multichain universe. As long as the MPC-like communication complexities in the relay network can be overcome, any parallelizable ZK prover can be used. The problem of verification of ed25519 signatures from the cosmos SDK-Ethereum light client discussed earlier is addressed using the above approach.
Bridges enable users to communicate messages between chains including digital assets (cryptocurrencies), state of the chain, contract requests, proofs and more. Electron labs aims to construct a bridge from the Cosmos SDK ecosystem (a framework for application specific blockchains) that uses IBC (Inter-Blockchain Communication) to communicate across all sovereign blockchains defined in the framework. Following this, the block headers and the proof are submitted to the smart contract, which then performs the verification on the Gnosis chain. While some of the hacks are not preventable just because one uses ZKP’s, the soundness of a ZKP extends the security of the blockchain consensus protocols to the bridge. Finally for users, we propose a two-part risk assessment framework to help choose the right bridge based on their transaction needs and desired security level.
Token bridges can be further classified into Lock and Mint type or Liquidity Network type. To conclude, bridges can be categorized in many ways, we’ve seen the categorization by validation method and the categorization by the applications built on top of the messaging infrastructure. As a result, users must trust the aggregators to provide a carefully selected set of options with minimal risk. For instance, TransferTo.xyz and Bungee allow users to access LI.FI and Socket's bridge aggregation services directly. One such bridge aggregator LiFi’s has written a section on Bridge Aggregation Protocols while contributing to the Crosschain Risk Framework. By combining the features of multiple bridges, aggregators may have a unique advantage in the bridge sector.
Based on the application or the utility of the bridge, there can be several types of bridges such as Token bridges, NFT bridges, Governance bridges, Lending bridges, ENS bridges etc. Additionally, some bridges use a hybrid model, further blurring the distinctions between the types. Before we dive into the different types of bridges, an important thing to note is that there are many different ways to describe the same technology and hence it can get a bit confusing while categorizing bridges. These two smart contracts communicate with each other through messages with cryptographic signatures.
This data from Chainalysis reveals that bridge hacks constitute a significant proportion of the total funds stolen in DeFi in 2022, amounting to an alarming 69% of the total. This can jeopardize even the security of the blockchain it connects to. However, if for example a bridge introduces new and unsafe tokens to the destination chain by minting, then these assets are only as secure as the bridge itself.