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.
The Stellar network is an open source, distributed, and community owned network used to facilitate cross-asset transfers of value. Stellar aims to help facilitate cross-asset transfer of value at a fraction of a penny while aiming to be an open financial system that gives people of all income levels access to low-cost financial services. Stellar can handle exchanges between fiat-based currencies and between cryptocurrencies. Stellar.org, the organization that supports Stellar, is centralized like XRP and meant to handle cross platform transactions and micro transactions like XRP. However, unlike Ripple, Stellar.org is non-profit and their platform itself is open source and decentralized. Stellar was founded by Jed McCaleb in 2014. Jed McCaleb is also the founder of Mt. Gox and co-founder of Ripple, launched the network system Stellar with former lawyer Joyce Kim. Stellar is also a payment technology that aims to connect financial institutions and drastically reduce the cost and time required for cross-border transfers. In fact, both payment networks used the same protocol initially. Distributed Exchange Through the use of its intermediary currency Lumens (XLM), a user can send any currency that they own to anyone else in a different currency. For instance, if Joe wanted to send USD to Mary using her EUR, an offer is submitted to the distributed exchange selling USD for EUR. This submitted offer forms is known as an order book. The network will use the order book to find the best exchange rate for the transaction in-order to minimize the fee paid by a user. This multi-currency transaction is possible because of 'Anchors'. Anchors are trusted entities that hold people’s deposits and can issue credit. In essence, Anchors serves as the bridge between different currencies and the Stellar network. Lumens (XLM) Lumens are the native asset (digital currency) that exist on the Stellar network that helps to facilitate multi-currency transactions and prevent spams. For multi-currency transactions, XLM is the digital intermediary that allows for such a transaction to occur at a low cost. In-order to prevent DoS attacks (aka spams) that would inevitably occur on the Stellar network, a small fee of 0.00001 XLM is associated with every transaction that occurs on the network. This fee is small enough so it does not significantly affect the cost of transaction, but large enough so it dissuades bad actors from spamming the network. The collected fee is then redistributed and added to an inflation pool. This inflation pool releases Lumens at a rate of 1% each year.