The hybrid PoW + PoS

Resources spent on hashing blocks when the algorithm PoW, huge and far exceed the capacity of the largest supercomputers. Besides PoW, a cryptocurrency can be attacked, temporarily rent a huge computing power.

PoS cryptocurrencies are vulnerable to other types of attacks. For example, the attacker wanted to create a fork of the blockchain — a longer alternative chain at the expense of spending the non-existent resources. Besides, he can get the support of other miners, because they also do not have to expend "real" resources.

Using a fork, the attacker can block a particular transaction and make an attack "double flow". Such attacks can be divided into near and far. When the middle attacks there is a replacement of the most recent blocks, and at the moment ranged attacks, the attacker can replace the history of the network.

The hybrid mechanism is the most safe, and therefore formed the basis of Emercoin project.

The standard hybrid scheme blockchain consists of two types of blocks. At the same time searched as blocks of PoW and PoS. "Proof of work" can be compared with checkpoint, mostly because PoW is used to distribute new coins. Proof of stake is necessary to protect the transactions, as the primary means for generating blocks of transactions.

For a successful attack on the project with the hybrid mechanism, the attacker must have 51% of the computing power of the network and 51% of the money supply. This creates for attacking two barriers of different nature that protect the network from being compromised.

As we mentioned, Emercoin has a hybrid mechanism of consensus, but in our project the emphasis is on more PoS. In fact, Emer is the PoS cryptocurrency in which the mechanism of PoW left for security reasons, and though playing an important but subsidiary role and approximately 80% of units closed PoS.