Motivation Recently, some bridges are attacked, resulting in significant losses: On Feb. 2, 2022, Wormhole was attacked with $320M loss; On Mar. 29, 2022, Ronin was attacked with $600+M loss. These losses raise a long-term question about the security level of heterogenous-chain interoperability and especially how we are able to mitigate…

Background The recent growth of decentralized applications such as decentralized finance (DeFi), non-fungible token (NFT), GameFi has dramatically created attention to and discussion of the next-generation worldwide web, namely, Web3. …

The Problem Optimistic rollup (OR) is becoming one of the most promising scaling solutions for Ethereum (L1) that offers much less gas cost (~1/6 to ~1/30), and almost the same security as L1. By submitting the off-chain transactions and their results on L1, the expensive on-chain computation can be offloaded to off-chain…

Background The boom of decentralized applications such as DeFi, GameFi has dramatically increased the demand for high-performance blockchain with low transaction fees. However, one key challenge of building high-performance blockchains is storage explosion. …

Brief Revisit of Uniswap V2 Uniswap V2 is the most popular and successful DEX by pricing a paired assets via the curve where x and y are the balance of the assets in the pool. Given Δx, to swap Δx for Δy, Uniswap V2 will perform the following calculation

Introduction In this article, we propose a blockchain network that acts as a centralized append-only distributed file system (DFS) such as Hadoop Distributed File System (HDFS) or Google File System (GFS). The potential advantages of blockchain as a distributed file system (BaaDFS) include: High availability: a user can tolerate failures of…

Introduction Currently, most of the blockchains adopt either a fixed-supply token model or inflation-supply token model. For example, Ethereum adopts inflation-supply token, although the Constantinople hard-fork will reduce block reward from 3ETH to 2ETH. …

In this article, we discuss a class of transactions that change the states of multiple shards, i.e., cross-shard transactions. …

In this article, we present a realization of Boson Consensus — Collaborative Mining, where rootchain and sharded blockchains use proof-of-work (PoW) consensus: The rootchain runs PoW, and each root block collects the headers/hashes of the blocks from sharded blockchains. …