Alternative consensus methods in the blockchain industry

03.12.2021 | mnalilovich

It is not always easy to reach consensus in peer-to-peer distributed systems. Cryptocurrency developers tend to opt for proof-of-work and proof-of-stake algorithms, but that’s all the world of consensus has to offer. The creators of digital assets and peer-to-peer networks are resorting to new methods that take into account the experience and shortcomings of their predecessors as well as allowing them to avoid some problems in the future.

dBFT

Delegated Byzantine Fault Tolerance allows for better scalability and also improves performance over previous solutions.

This algorithm is essentially similar to DPoS - Delegated Proof-of-Stake Consensus. Each participant in the dBFT network has an absolutely equal vote, with which the current delegate leader is selected. Usually, there are several delegates in the network, and it is they who determine the rules. If delegates are not performing up to their job standards, token holders can vote them out and bring in other delegates.

This approach can be considered one of the forms of absolute democracy. Clear proof of this is the method of proposing and validating blocks. Each vote has the right to propose a transaction to its delegate. The delegate adds all the proposals into the block, which will later be included in the blockchain. But the most interesting thing in Delegated Byzantine Fault Tolerance is the voting for new blocks. From the delegates, a speaker is chosen randomly. The speaker builds a new block from the transactions that waits to be validated. Then, the speaker sends the proposal to the elected delegates. The block is added to the blockchain if more than two-thirds of the delegates reach a consensus and validate it, otherwise, a new speaker is elected.

However, not everyone can become a delegate. To do this, it is necessary to meet several requirements, in particular, the good Internet connection and equipment, as well as a certain amount of coins on the account.

Hyperledger

Hyperledger is an ecosystem of open source blockchain projects and related tools hosted by the Linux Foundation. Hyperledger is the result of the collaboration from the blockchain industry to produce standardized modules that can be used in the development of blockchain-based distributed ledgers. The possibilities and useful applications for Hyperledger are quite large, including the priority in Web 3.0, the third generation of internet.

Several ecosystems have already been built on the basis of Hyperledger, among which the most interesting are Fabric and Sawtooth.

Although Hyperledger has its own method of reaching consensus, called Practical Byzantine Fault Tolerance, it is not very reliable and does not allow building networks with a small number of participants, and also requires a lot of overhead to ensure the interaction between the participants. Only Fabric decided to use a native solution in its work. Therefore, this ecosystem is more suitable for building small solutions that work in trusted networks and in the corporate segment without access to a distributed ledger from outside. But Intel took a different path.

However, it should be understood that Hyperledger is based primarily on building a network. Distributed information exchange plays the main role here. While other networks are building around cryptocurrency, Hyperledger doesn’t devote much time to the financial side of the issue.

Proof of Elapsed Time

This algorithm was proposed by Intel for its Sawtooth distributed ledger ecosystem. Proof of elapsed time is inherently similar to Proof of work. Only, unlike the latter, there is no need to spend so much energy and special equipment. Each latest generation Intel processor is capable of participating in block generation. To do this, it has built-in the ability to execute special instructions required to generate new blocks.

However, unlike PoW, there is no need to do constant math. Each participating node in the network is required to wait for a randomly chosen time period, and the first one to complete the designated waiting time wins the new block. Each node in the blockchain network generates a random wait time.

Proof of Weight

The Proof of Weight algorithm hides several similar methods of achieving consensus. In general, it is similar to the proof of stake method. Instead of the amount of coins in the wallet or their storage time, another significant parameter of the network participant is used, the so-called weight.In each specific case, the reputation of the validator may be used, or the amount of information stored. The latter is used to create a peer-to-peer distributed storage system. Here, the mining process, in fact, is the usual storage of files for a certain time. In fact, mining cryptocurrency is in fact selling free space on your computer’s hard drive. However, a very interesting consensus-building algorithm proposed by the BitTorrent developer is gaining popularity, which led to a shortage of storage devices in the market.

Proof of Spacetime

With this approach, network participants allocate an amount of memory or disk space to solve math random data. The more storage capacity a miner has, the higher the chance that miner will be able to match the required hash value of a new block generation, given data encoding has remained in physical storage continuously over a specified period of time. That’s shy it has such a name. However, this algorithm has one significant drawback - information rewriting occurs quite often, which leads to premature failure of the storage device.

Conclusion

In the last few years, a craze for cryptocurrencies has gripped the world. Some use them as an investment tool, the others as a convenient and reliable payment method or the financial privacy that traditional systems are failed to provide.Although free digital assets still have many unresolved problems, but most importantly, security and a solution to the problem of reaching consensus have already been found. This allows us to develop other aspects, like fully-fledged peer-to-peer ecosystems, and bring the era of the new WEB 3.0 Internet closer.