Cosmos

Technical details:  Architecture The Cosmos network consists of many independent, parallel blockchains, called zones, each powered by classical Byzantine fault-tolerant (BFT) consensus protocols like Tendermint (already used by platforms like ErisDB). Some zones act as hubs with respect to other zones, allowing many zones to interoperate through a shared hub. The architecture is a more general application of the Bitcoin sidechains concept, using classic BFT and Proof-of-Stake algorithms, instead of Proof-of-Work. Cosmos Hub The first blockchain in the Cosmos network is the Cosmos hub. The Cosmos hub connects to zones via the novel IBC (inter-blockchain communication) protocol and keeps a record of the total number of tokens in each zone. Because all inter-zone token transfers go through the Cosmos hub, you can transfer tokens from one zone to another, quickly and securely, without the need for a liquid exchange or a trusted third party between zones. The Cosmos hub can connect to many different kinds of zones, as long as each zone speaks IBC. As a result, Cosmos can support a variety of currencies and scripting languages like those found in Bitcoin, Ethereum, ZeroCash, CryptoNote, and more. Interoperability Cosmos can interoperate with multiple other applications and cryptocurrencies, something other blockchains can’t do well. By creating a new zone, you can plug any blockchain system into the Cosmos hub and pass tokens back and forth between those zones, without the need for an intermediary. Scalability Scaling is another open issue for blockchains. Both Ethereum and Bitcoin support only a fraction of the transactions seen daily on payment networks like Visa or Mastercard. In contrast, zones allow Cosmos to scale out indefinitely. If your transaction speed slows in one zone because too many people are using it, you simply add another zone to the hub and direct half the users over that zone, thereby doubling your transaction speed. Meanwhile, the Cosmos hub ensures that any zones connected to it remain in sync. Upgradability Another problem blockchains run into is how to handle upgrades when new versions come out. Getting all of the validators (“miners” in the case of Bitcoin) to upgrade to a new version of a blockchain simultaneously is tricky, and could lead to hard forks. This is exactly what happened when Ethereum hard-forked into ETH and ETC due to political/governance issues surrounding the DAO hack. With Cosmos, upgrading is not an issue. You simply plug a new zone into the Cosmos hub, and invite users to move their funds over to it at their leisure. Proof of developer:  Public team