Bytecoin is the first cryptocurrency created with CryptoNote technology. Bytecoin allows users to make absolutely anonymous money transfers through the CryptoNote algorithm. CryptoNote uses CryptoNote ring signatures to provide anonymous transactions and allows you to sign a message on behalf of a group. The signature only proves the message was created by someone from the group, but all the possible signers are indistinguishable from each other. Even if outgoing transactions are untraceable, everyone may still be able to see the payments received and thus determine one's income. By using a variation of the Diffie-Hellman exchange protocol, a receiver has multiple unique one-time addresses derived from his single public key. After funds are sent to these addresses they can only be redeemed by the receiver; and it would be impossible to cross-link these payments. As a primarily peer-to-peer (p2p) payment system, Bytecoin has many of the same use-cases as Bitcoin. Created in 2012, Bytecoin is one of the earliest developed cryptocurrencies. Until recently, the team behind the coin has kept themselves anonymous. Now, though, they’ve opened up multiple communication channels, removed some layers of anonymity, and even built several local communities. Bitcoin’s PoW consensus algorithm heavily favors miners that use powerful GPU and ASIC machines over those trying to mine with CPUs. This causes the network to centralize around the more powerful miners. Bytecoin attempts to close the gap between these two classes of miners with a new algorithm, Egalitarian Proof-of-Work (PoW). Egalitarian PoW uses a version of skrypt, a proof of work function similar to the hashcash function used by Bitcoin. The difference between the two is that scrypt isn’t memory bound. Because of this, you can produce highly efficient CPU mining rigs. GPUs will always be about 10 times more effective, though. The Bytecoin project has been fairly fractured since its inception in July 2012. Previously, several isolated teams worked on the project without seemingly communicating with each other. This led to numerous forks and versions of the coin. In July 2017, the team decided to change their image and provide more transparency to the community. The team still remains pseudo-anonymous by only providing names and headshots on their webpage – no bios or social media links. But, it’s tough to expect more from a project that’s focused on privacy. The team has been busy at work refactoring their code and are planning to release a new public API on February 6, 2018. They’ll also be entering the Asian, Middle East, and African markets throughout 2018.
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 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. While the Cosmos Hub is a multi-asset distributed ledger, there is a special native token called the atom. Atoms have three use cases: as a spam-prevention mechanism, as staking tokens, and as a voting mechanism in governance. As a spam prevention mechanism, Atoms are used to pay fees. The fee may be proportional to the amount of computation required by the transaction, similar to Ethereum’s concept of “gas”. Fee distribution is done in-protocol and a protocol specification is described here. As staking tokens, Atoms can be “bonded” in order to earn block rewards. The economic security of the Cosmos Hub is a function of the amount of Atoms staked. The more Atoms that are collateralized, the more “skin” there is at stake and the higher the cost of attacking the network. Thus, the more Atoms there are bonded, the greater the economic security of the network. Atom holders may govern the Cosmos Hub by voting on proposals with their staked Atoms.