Generic Superlight Client for Permissionless Blockchains
This work addresses a fundamental challenge in broadening blockchain usage for applications like multi-chain wallets and DApp browsers, though it appears incremental as it builds on existing light client models with a game-theoretic approach.
The paper tackles the problem of enabling efficient transaction verification for light clients in permissionless blockchains by designing a generic superlight-client protocol that reduces computational cost to a small constant, allowing clients to use as few as one or two full nodes.
We conduct a systematic study on the light client of permissionless blockchains, in the setting where the full nodes and the light clients are rational. Under such a game-theoretic model, we design a superlight-client protocol to enable a client to employ some relaying full nodes (e.g. two or one) to read the blockchain. The protocol is "generic", i.e., it can be deployed disregarding the underlying consensuses, and also "superlight", i.e., the computational cost of the light client to predicate the (non)existence of a transaction in the blockchain becomes a small constant. Since our protocol resolves a fundamental challenge of broadening the usage of blockchain technology, it captures a wide variety of important use-cases such as multi-chain wallets, DApp browsers and more.