Understanding Ethereum ERC-7786: A Unified Multichain Collaboration Standard, Is the ETH Ecosystem Entering the "Unified" Era?

The significance of ERC-7786 is not only to make cross-chain more convenient, but also to try to establish a unified specification for "multi-chain collaboration" from the root to combat "entropy increase", which can not only further promote the "unified" process of on-chain liquidity, but also promote the maturity of multi-chain ecology. (Synopsis: Securing Ethereum EIP-7702 Upgrade: A Proxy Model for Secure EOA to Smart Wallet Transition) (Background supplement: The struggle of human nature that cannot be solved by code: infighting, exodus and the future of Ethereum's inner circle) The Ethereum ecosystem may be about to enter the era of unification from the L2 "Spring and Autumn Warring States" chaotic stage. The key is ERC-7786, which is in progress, which attempts to set a common cross-chain communication "interface specification" for Ethereum, so as to integrate various messaging standards under a unified API and realize mutual communication between smart contracts of different blockchain networks in the Ethereum ecosystem. As early as April 15, Ethereum Foundation member Joshrudolf.eth publicly emphasized that "cross-chain messaging is one of the key elements to solve the problem of Ethereum's cross-chain user experience." So what exactly is ERC-7786, what problem is it to solve, and why is it important? This article will walk you through this new standard that deserves the attention of all Ethereum users. 01 Ethereum, the need to unify cross-chain communication protocols As we all know, from the original Cosmos, Polkadot's multi-chain concept, to the Rollup boom in the Ethereum L2 era, especially the OP Stack, Arbitrum Nova, Starknet and other application chains have developed greatly, making liquidity more and more decentralized on Ethereum and L2. According to the incomplete statistics of L2BEAT, Ethereum L2 has hundreds in a broad sense, which gives rise to a long-standing problem - the extreme fragmentation of liquidity. You know, even if they are based on the Ethereum ecosystem, but different L2s themselves do not communicate with each other, if users want to transfer assets from Arbitrum to Starknet, or perform contract interaction operations across different L2s, they can only use cross-chain bridges or cross-chain messaging protocols to achieve secure interaction between contracts, users and assets between multiple networks. Source: L2BEAT This not only makes users pay more friction costs every year due to cross-chain obstacles, but more importantly, the Ethereum ecosystem, especially the synergy between L2 is also seriously weakened, and although many protocols have implemented inter-chain communication functions, each protocol has its own interface, call mode and security model, developers can hardly reuse code or interface logic between different protocols, directly resulting in repeated "wheels" and high operation and maintenance costs, and the user experience is extremely fragmented. Therefore, ERC-7786 is proposed precisely to break this fragmented ecosystem and provide a unified standard interface for all inter-chain communication protocols, so that DApps can securely communicate with any chain through the same "gateway" without binding a specific protocol: The standard is led by OpenZeppelin and supported by multiple cross-chain and modular projects, including the Ethereum Foundation, Axelar, as a DApp-oriented application 's unified cross-chain messaging interface standard, which aims to standardize a common interface for decentralized applications (DApps) to securely send and receive messages across multiple blockchains. Source: erc7786.org 02 ERC-7786: Cross-chain communication "unified interface" If ERC-7786 is summarized in one sentence, it is like "ERC-20" in the field of cross-chain communication. Just as ERC-20 provides a standard interface for tokens, ERC-721 defines a common specification for NFTs, ERC-7786 also tries to establish a unified and common "communication socket" for cross-chain messaging - you can compare it to the "USB standard" in the Web3 world, as long as it is connected to the specification interface, any protocol can be plugged and played. The following diagram shows the core components and processes of ERC-7786, showing how to send and receive messages between different blockchains through standardized interfaces, and one ERC-7786 message consists of four basic elements: Sender: Identified in CAIP-10 format (e.g. eip155:1:0xabc... Receiver: Also identifies the destination address for CAIP-10 Payload: Arbitrary execution data (bytes) Attributes: Additional arguments, such as gas limit, processing priority, etc., expressed in the form of a function signature (such as minGasLimit (uint256)) Source: erc7786.org Among them, sendMessage () is used for chain A to initiate the message, executeMessage () is used for chain B to receive and execute, this "send-receive closed loop" constitutes the basic logic of cross-chain communication, and also makes DApp only needs to package the standard interface at one time, and it can be compatible with multiple cross-chain protocol modules at the same time, realizing "protocol decoupling + communication freedom" in the true sense. ERC-7786 has also announced that the interface is fully functional and is awaiting the final merging of the binary interop address specification (i.e., uniform address encoding). In the future, there are plans to add a "Gas Sponsorship" extension that allows users to prepay gas by a third party when executing transactions on the target chain, thereby optimizing the user experience of inter-chain interaction. More importantly, the ERC-7786 design supports modular adaptation, and developers can build adapters for existing mainstream cross-chain protocols (such as Axelar, LayerZero, Wormhole, etc.), without refactoring logic, and can quickly be compatible with ERC-7786 standard interfaces. This means that even if users, liquidity, and applications are distributed across multiple L2 or heterogeneous chains, DApps can build native cross-chain calling capabilities with ERC-7786, without binding specific bridge protocols or relying on cumbersome UI switching, which can greatly improve the overall experience and reduce integration complexity. It is worth mentioning that ERC-7786's Attributes mechanism also allows access to extension suite functions of different cross-chain protocols, such as verification logic, state proof, limit control, etc., without affecting the standard main process, which leaves a highly flexible interface space for the evolution of middleware and authentication mechanisms. From this point of view, the significance of ERC-7786 is not only "compatible with multiple cross-chain protocols", but also represents that the Web3 multi-chain architecture is moving from "cross-chain deployment" to a new era of "native interoperability". 03 What does ERC-7786 bring? For this reason, ERC-7786 is widely regarded as an important infrastructure to promote Ethereum and the multi-chain ecosystem to higher interoperability, not only breaking through long-standing protocol barriers, but also laying a unified standard infrastructure foundation for future cross-chain function expansion, verification mechanism upgrades, and multi-chain collaboration. From a practical landing point of view, the value brought by ERC-7786 can be attributed to two core beneficiaries - developers and end users: For developers, it is only necessary to open...