Author: Yue Xiaoyu
To summarize, in one sentence: ERC-7802 is a cross-chain standard that extends new features for existing ERC-20 tokens, enabling standard cross-chain functionality by calling the ERC-7802 interface.
01 Background
ERC-7802 is a cross-chain token standard jointly proposed by the Optimism team and the Uniswap team, aiming to maintain a unified standard for tokens during cross-chain operations.
We can see that the collaboration between Uniswap and Optimism is deepening: Uniswap previously announced the launch of Unichain, which is part of the OP Superchain ecosystem, and together they proposed this cross-chain standard.
The proposal of ERC-7802 aims to standardize cross-chain operations, which is very important for DEXs (decentralized exchanges) like Uniswap and L2 solutions like Optimism.
The token standards on Ethereum have been evolving, from ERC-20 to ERC-721, ERC-1155, and so on. ERC-7802 is part of this evolution, focusing on solving the specific issue of cross-chain interactions.
02 Design Principles
Overall, the design principle of ERC-7802 is 'bridge agnosticism': in cross-chain scenarios, it aims to separate the token contract from specific cross-chain bridging technologies or protocols as much as possible.
This is a modular design that effectively shifts complexity to the cross-chain bridge, separating cross-chain logic from the token contract, making the structure of the token contract simpler and more modular.
The implementation of tokens only needs to focus on their basic functionality, without having to consider the specific implementation of cross-chain transfers.
The bridging protocol takes on all the complexities related to cross-chain transfers, including transaction validation, asset locking and releasing, cross-chain communication protocols, and so on.
ERC-7802 defines a standardized interface for how tokens interact with cross-chain bridges but does not concern itself with how these bridges are specifically implemented.
Any bridging protocol that complies with ERC-7802 can use this interface for cross-chain operations without needing to modify the token contract itself.
03 Specific Implementation
ERC-7802 defines a standardized interface that contains two key functions:
crosschainMint: Minting tokens on the target chain for the recipient as a result of destroying tokens on the source chain.
crosschainBurn: Burning tokens on the source chain and initiating a cross-chain transfer, which is usually the starting point of cross-chain transfers.
It is important to note that cross-chain minting and burning are different from local minting and burning. In cross-chain operations, the total circulating supply on all chains remains unchanged, as tokens are transferred between chains rather than being truly created or destroyed.
ERC-7802 contracts support ERC-165, which is an interface detection standard that allows smart contracts to declare which interfaces they support. This helps ensure compatibility of contracts for cross-chain operations.
More importantly, ERC-7802 is compatible with ERC-20.
ERC-20 is a widely used fungible token standard on Ethereum, so compatibility with ERC-20 is very important for the new standard, making it easier for existing tokens to cross-chain into new ecosystems.
In this way, existing tokens can exist as regular ERC-20 tokens, and then implement cross-chain functionality through the ERC-7802 interface.
04 Protocol Value
Addressing the multi-chain experience issue is a significant trend. ERC-7802 actually establishes cross-chain standards from the ground up at the protocol level, complementing the 'chain abstraction' narrative.
ERC-7802 directly supports the goal of chain abstraction by providing a standardized cross-chain token transfer protocol, allowing assets to flow seamlessly across different chains.
The realization of chain abstraction requires the collaboration of various technical standards and protocols, and ERC-7802 can be seen as a key building block among them.
It can be said that ERC-7802 provides a concrete solution for chain abstraction at the technical level, addressing the technical issues of token cross-chain transfers, while chain abstraction utilizes these solutions to provide a higher level of user experience and application development framework.
More importantly, this standard proposed by OP also lays the foundation for interoperability within the OP Superchain ecosystem.
The current protocol standard is still in the discussion phase, and we can continue to monitor it.
