Beam Mimblewimble is a scalable, fungible, and confidential cryptocurrency based on the Mimblewimble implementation. WHY BEAM? Core features include complete control over your privacy, All transactions are private by default, No addresses or other private information are stored on the blockchain, Superior scalability due to compact blockchain size, Opt-in Auditability, Support online and offline transactions, atomic swap, hardware wallets integration. Governance model No premine, No ICO. Backed by Treasury Establishing a non-profit foundation to govern the protocol after Mainnet launch How does it work? Wallets’ owners create new transaction using secure channel either online or offline Both wallets participate in signing the transaction using Schnorr protocol Wallet sends transaction to node Each transaction contains a list of Inputs and Outputs represented by Pedersen Commitments, as well as explicit fees and kernels. Each transaction also contains non-interactive zero knowledge range proof to verify that the output transaction value is positive Transaction is verified by the node Each transaction is verified with respect to the recent blockchain state which is stored as a Merkle Tree. The root hash of the tree is recorded in block header along with a proof of work. In addition, each node periodically creates compacted history to allow ‘fast sync’ of new and existing nodes. Transaction is added to the mining pool A block is mined every minute and is sent back to the node for verification and distribution. Mined blocks containing the new transactions are sent to the known peers A valid block that is extending the longest chain is accepted as a new Tip and propagated further until full consensus is reached. Fast sync When a new node connects to the network for the first time it can request compacted history containing only system state and blockchain headers. There is no need to retrieve the entire transaction history.
QuarkChain is a secure, permission-less, scalable, and decentralized blockchain. One of the goals of QuarkChain is to utilize sharding technology to deliver over 1 million transactions per second (tps). Essentially, QuarkChain markets itself as a peer-to-peer blockchain with a high capacity throughput to help deliver fast and secure decentralized applications. The team behind QuarkChain created this blockchain to resolve the issue of scalability that all the major blockchains are currently facing. The team feels that because of the urgency of this issue, the Bitcoin community simply cannot afford to wait until they all agree on a solution. Instead, they feel that by offering different solutions, such as the one inherent in QuarkChain, this compels the community to split via a hard fork and find the solution that works best. QuarkChain encourages increased decentralization through multiple cheap nodes that then create a cluster that works as a super-full node. This prevents the high expenses associated with super-full nodes when the tps gets high. In terms of protection, all transactions within QuarkChain get the protection of 50 percent of the network’s hash power. This makes a double-spending attack incredibly challenging, particularly when combined with QuarkChain’s decentralized nature. QuarkChain relies on a two-layer blockchain structure. Sharding blockchains known as shards are the first layer, while the second layer is a root blockchain that confirms the shards’ blocks.The major work on QuarkChain began in Q2 2017 with research into the problem of blockchain scalability. In Q4 of that year, the team drafted the whitepaper. In February 2018, it released the white paper and completed verification code 0.1. March 2018 saw the 0.1 versions of both the wallet and testnet. Now in Q2, the team is working on the testnet 1.0 and smart contract 0.1. In Q4 2018, the team will have the QuarkChain Core 1.0, along with the mainnet 1.0 and the SmartWallet 1.0. By Q2 2019, both the SmartWallet and QuarkChain Core will be in their 2.0 versions. QuarkChain is a decentralized blockchain network that aims to resolve the issues of scalability that plague existing networks by using sharding technology. In this way, QuarkChain can dramatically extend the usefulness of blockchain technology since many applications are limited by the scalability of existing blockchain networks. The project is still in progress, but QuarkChain has already made many positive steps and already began invite-based beta testing for the testnet, showing significant progress and potential. The main features of Quarkchain are: 1. Reshardable two-layered blockchain: Quarkchain consists of two layers of blockchains. We apply elastic sharding blockchains (shards) as the first layer, and a root blockchain as the second layer that confirms the blocks from the first layer. The second layer that confirms the blocks from the first layer. The second layer is flexible to be resharded as needed without changing the root layer. 2. Guaranteed security by market-driven collaborative mining: To ensure the security of all transactions, a game-theoretic framework is designed for incentives, where at least 50% of overall hash powers are allocated to the root chain to prevent double spending attack on any transactions. 3. Anti-centralized horizontal scalability: In any blockchain network with a high TPS, a super-full node can be extremely expensive, which encourages centralization. In contrast, QuarkChain allows multiple cheap nodes forming a cluster to replace a super-full node. 4. Efficient cross-shard transactions: Cross-shard transactions in QuarkChain can be issued at any time, and confirmed in minutes. The speed of cross-shard transactions increases linearly as the number of shards increases. 5. Simple account management: There is only one account needed for the entire blockchain (shards) in QuarkChain. All cryptocurrencies from different shards are stored in one smart wallet.