Grin coin is a private & lightweight open source project based on the mimblewimble blockchain implementation. MimbleWimble is a lightweight blockchain protocol proposed by anonymous author that goes by the name Tom Elvis Jedusor (inspired by Harry Potter) in July 2016. Since then, the proposal has gained a huge following among Bitcoin and privacy advocates. Unlike bitcoin or ethereum, there are no addresses in Grin. In order to transact using Grin, both wallets must communicate with each other online with the results broadcasted to the network. Another key different is that transaction history (sender, receiver, amount) will not be recorded on the blockchain. Due to the removal of these information from the transaction, the data size remains small and that keeps the blockchain lightweight. New nodes can easily join the network without having to download a large blockchain. Grin coin was launched without an ICO, fundraising, or pre-mine. Developers around the world contribute openly with the goal to ensure the coin distribution remains as fair as possible. There are 2 popular wallets widely available to interact with the Grin network. Grin core wallet: https://www.coingecko.com/buzz/how-to-use-grin-wallet-to-send-receive-grin-coins Wallet713: https://www.coingecko.com/buzz/how-to-use-grin-wallet713-to-send-and-receive-grin-coin-step-by-step-guide The consensus algorithm used by Grin is the Cuckoo Cycle proof-of-work based. There are 2 hashing algorithms involved with Grin. Cuckoo-29 is meant for GPU mining while Cuckoo-31 is meant fo ASIC mining. This is a deliberate design to encourage miners to eventually move into ASIC mining for efficiency while keeping it fair at the beginning of the launch. Grin coin has launched its mainnet on 15th January 2019 and is now available for mining and trading.
Sia is a decentralized cloud storage platform similar in concept to Dropbox and other centralized storage provider where instead of renting storage space from a centralized entity, clients rent storage space from other peers. The only difference is Sia uses blockchain to facilitate transactions Nodes provide storage to clients using the Sia blockchain as contracts. Before storing the data, the data is encrypted into many pieces and uploaded to different hosts. Siacoin is created by David Vorick and Luke Champine of Nebulous Inc. As the traditional storage platforms are higher in cost, more expensive and data is not well protected. Siacoin promises to offer secured storage transactions with smart contracts which is more affordable and reliable. Moreover, it is completely open source which means many individuals have contributed to Siacoin’s software hence there will be an active community building innovative applications on top if the Sia API. In 2018, Siacoin aims to introduce file sharing and be the go-to cloud storage platform for companies. Their goal is divided into 3 time frames which are short-term, medium-term and long-term development. Short-term development focuses on file sharing between Sia users. This allows Sia users to share files in the platform without having to take it off the cloud while increasing network utilization. Medium-term development’s goal is to enhance partnerships. This means reaching out to large companies like Netflix and Dropbox to hopefully be able to be their storage and distribution framework. Lastly, long-term development aims to expand its horizon to share files with non-Sia users and support mobile wallets.