It took 75 tweets but the founder of blockchain Ethereum Vitalik Buterin made it clear the roadmap for the implementation of a new consensus mechanism that promises to dramatically increase the speed at which new entries can be added to the distributed electronic register technology.
Buterin dedicated most of the tweets to explaining the history of Ethereum's developer efforts to create a consensus mechanism of Proof of Stake (PoS) that simplified the process and at the same time fought nefarious attacks to control the content of blockchain.
that a PoS system will be implemented independently of another effort to implement sharing on Ethereum. (Sharding is a way of distributing the computational work necessary to validate new documents, known as blocks, on the technology of the distributed ledger). The efforts for the development of PoS and sharding had been part of a project, but will now be implemented separately.
Proof of Work and Proof of Stake
The two most popular mechanisms or algorithms for authenticating new entries on a blockchain and changes to networks are Proof of Work (PoW) and Proof of Stake.
PoW algorithms force computers on the peer-to-peer (P2P) network to use CPU power to resolve complex cryptographic equations before they are authorized to add data to a blockchain register; those computer nodes that complete the fastest equations are rewarded with digital coins, such as Ether on Ethereum or bitcoins on concurrent technology. The process of earning cryptocurrency through PoW is known as "mining", as in extraction bitcoins.
As the name implies, the PoS consensus models allow those with the most digital coins (the biggest mail) to govern a cryptocurrency or a commercial blockchain. To date, however, the most popular blockchain-based cryptocurrencies – Bitcoin, Ethereum (Ether) and Litecoin – have used PoW as a consensus mechanism.
While PoW algorithms are excellent for ensuring the authenticity of new documents published in a registry, they are also slow and expensive to manage.
The PoW process consumes a lot of electricity, both from the processors running 24 hours a day, and from the need to cool down server farms dedicated to data mining operations. These mining operations are absorbing so much electricity that cities and even countries have begun to block mining operations.
PoW protocols can also be extremely slow due to the long process necessary to solve mathematical puzzles; The approval of a new entry on a blockchain ledger can take 10 or more minutes. PoW's algorithms are, however, excellent for countering users who would try to play blockchain, since it is simply too costly to spend time and CPU power.
In contrast, PoS algorithms can complete new blockchain entries in seconds or less.  "Proof of Stake's algorithms definitely have the potential to overcome Proof of Work," said Vipul Goyal, an associate professor at the Computing Department of Carnegie Mellon University (CMU). "However, there are still some important research challenges that need to be overcome before this happens."
Ethereum started working on a PoS system in 2014 and last year introduced the mechanism on a testnet called "Casper" (as in Casper the Friendly Finality) Gadget or Casper FFG). Casper had to be superimposed on the current Ethereum PoW algorithm. His release had been scheduled for some time this month, but has been postponed.
There were also internal development wars on how Casper should be implemented.
As with other PoS models, Casper's consent protocol would work by creating "bound validators" or users who need to deposit a security deposit before they can be allowed to be part of the blockchain or electoral community consent. As long as the bounded validators act honestly on the blockchain, they can remain in the consensus community; if they try to cheat the system, they lose their interest (their money). The PoS system of Ethereum Casper would allow a consensus mechanism to process new transactions in about four seconds.
A hybrid system
Last year, two developments in the effort to implement a new consensus model came in the form of an independent PoS mechanism called Serenity and a PoW / PoS hybrid system called Metropolis. Metropolis was divided into two phases: the development of a Byzantine error tolerance mechanism launched last year and a project known as Constantinople – the PoW / PoS hybrid system.
The name of Constantinople was abandoned at the beginning of this year and the effort to implement a new Casper PoS and the sharding system are now defined as Ethereum 2.0.
The PoS system, whether hybrid or autonomous, required that the validators deposit 1,500 Ether coins to become part of the consensus mechanism. In its tweet storm, however, Buterin announced that the number of Ether coins needed to become a validator will now be 32.
Jake Yocom-Piatt, creator of the Decred digital currency network, believes that the best governance model both the one that employs both PoW and PoS Mechanisms, as proposed by Buterin and the Ethereum development team.
In a hybrid model, the deference is given to PoS validators that can ignore the bad behavior on the PoW network.
"If you are a Proof of Work Miner and you are playing games and causing problems to our network, network stakeholders can penalize them and deprive them of their premiums," said Yocom-Piatt. "You can also vote on changes to consensus rules, which act as a mechanism for resolving disputes and making decisions for important decisions in cryptocurrency," said Yocom-Piatt, referring to new versions of software and other blockchain changes.
In Ethereum The latest 2.0 model, the blockchain would have grown in blocks using the current PoW algorithm, "but every 50 blocks is a" PoS "checkpoint where the purpose is evaluated through a validator network PoS, as explained in a white paper.
its development life cycle, the PoS protocol has faced a series of challenges, the most difficult of which is known as "backward corruption", which could undermine the authenticity of a blockchain. For example, a group of users on a blockchain can hold the majority stake and then sell that share. In a PoS system, such entities could still contain cryptographic keys that in the past gave them the power to govern and use that authority to create a new blockchain or "chain of attack" from the main chain (known as fork). In fact, they would still have their money aimed as if it had never been sold and controlled the direction of the blockchain.
"If the chain of attack diverges from the main chain at a fairly recent time, this is not a problem, because if the validators sign two conflicting messages for the two conflicting chains, this can be used as evidence to penalize them and take away their deposits, "Buterin wrote in his Twitter thread. "But if the divergence took place a long time ago (hence, long-range attack), the attackers could withdraw their deposits, avoiding sanctions on both chains."
To cope with long-range attacks, the developers of Ethereum have introduced a change that requires access to clients at least once every four months and that their deposits take four months to retire, so the company has to change the time. incentive to avoid a penalty would no longer be available.
The developers of Ethereum also considered other consensus algorithms "inspired by the traditional theory of tolerance to Byzantine errors", such as Consensus of Bet, but eventually abandoned them as "too risky".
Shawn Dexter, an analyst at Mango Research, said that the most recent Ethereum update has confused people because much of the explanatory information is contained in the comment sections of various forums. Even in a flare last week, Dexter warned that things could change between now and when a PoW / PoS and sharding algorithm is implemented.
Casper and sharding will probably not be launched together on the chain of beacons, Buterin said, saying that while they will be implemented on the same chain, Casper could come sooner or sharding. Both will be implemented on a new overlay network known as Beacon Chain.
Buterin concluded his Twitter thread by saying that there is no formal timing to implement the new consensus mechanism. While at one point he said that Casper would be released this month, his last tweet said that there are still "formal tests, refinements of specifications and progress in progress on implementation", which have already been initiated by three developer team.
Martha Bennett, a principal analyst with Forrester Research, warned to speculate on when Ethereum 2.0 would be released. "The PoS consensus design required several iterations," he said via e-mail, "and we simply will not know it until it is implemented and has been running for a while if it will work the way you want it or not. . "