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.
ChainLink is a decentralized oracle service, the first of its kind. When Ethereum went live in 2015, it revolutionized what blockchain could bring to enterprise solution and traditional business. Blockchain was no longer just a medium for new age financial transaction, confined to Bitcoin’s potential to disrupt traditional currency exchange. With Ethereum powered smart contracts, Vitalik Buterin opened up a Pandora’s Box of use cases for blockchain technology. Problem is, per their design, smart contracts can only manage data on the blockchain. Their potential, the ability to provide tamperproof, decentralized applications for uses the world over, is still largely untapped, as many of the smart contract programs built on Ethereum lack a bridge to the real world industries they’re trying to improve. ChainLink’s first component consists of on-chain contracts deployed on Ethereum’s blockchain. These oracle contracts process the data requests of users looking to take advantage of the network’s oracle services. If a user or entity wants access to off-chain data, they submit a user contract (or requesting contract) to ChainLink’s network, and the blockchain processes these requests into their own contracts. These contracts are responsible for matching the requesting contract up with the appropriate oracles. The contracts include a reputation contract, an order-matching contract, and an aggregating contract. The first of these, the reputation contract, is exactly as it sounds: it checks an oracle provider’s track record to verify its integrity. In turn, the order-matching contract logs the user contract’s service level agreement on the network and collects bids from responsible oracle providers. Finally, the aggregating contract accumulates the collective data of the chosen oracles and balances them to find the most accurate result. Unfortunately, the ChainLink team does not offer a roadmap, but a testnet of ChainLink’s services should come sometime within Q1 of 2018. Generally, the project’s general lack of marketing and concrete updates have frustrated community members in the past. Sergey Nazarov, the project’s CEO, is known for a quiet community presence that favors of behind-the-scenes work on ChainLink. The team may not hype their project much, but for what it’s worth, they sacrifice brand marketing in favor of product development–and some community members find this focus to be refreshing. For instance, they’ve established an oracle with Swift Bank, and have a few quiet partnerships with zepplin_os and Request Network. Chainlink has the potential to connect smart contracts with the outside world. It may allow parties to smart contracts to be able to receive external inputs that prove performance and create payment outputs that end users want to receive, such as bank payments. This has the potential to allow smart contract to mimic the vast majority of financial agreements currently available in the market. With the ChainLink Network, anyone can securely provide smart contracts with access to key external data and any other API capabilities, in exchange for financial reward. Although it remains to be seen how the incentive system will operate, there is potential for rewards similar to those available for crypto miners to be available to Node Operators that provide useful data to the Chainlink network.' Check out CoinBureau for the complete review on Chainlink.