Comparative guide to blockchain consensus algorithms: PoW and PoS

The decentralized decentralized network of blockchain technology creates an uncorruptible system and provides greater security, transparency, and immutability. You probably already know that. But have you ever asked yourself how a system without a central authority is managed, or how decisions about transactions are verified?

One of the most important promises of blockchain technology is a trustless peer-to-peer system in which the community helps verify whether transactions are genuine. But have you ever thought about exactly how that happens? Well, different blockchains use different methods called blockchain consensus algorithms.

These algorithms, also known as consensus protocols, are a set of rules by which a network operates. If that sounds interesting, read our comprehensive guide to understanding what blockchain consensus algorithms are, their purpose, how they work, and the differences between the two most popular algorithms in use today please.

How blockchain works

Blockchain is a system for recording information that cannot be tampered with or hacked. Blockchain, also known as distributed ledger technology (DLT), uses decentralized cryptographic hashes to create a secure and transparent history of digital assets.

Although blockchain runs on more complex systems, the simplest example of how blockchain works is Google Docs. Documents created in Google Docs can be shared and distributed within your team instead of being copied and forwarded.

Google Docs uses a decentralized distribution chain, allowing all team members to access documents at the same time. All changes made on the document are recorded in real time and transparent as no member is locked out.

Each block on a chain of blocks contains multiple transactions. Every time a user adds a new transaction to the blockchain, a transaction record is added to the ledger of all participants.

Similarly, whenever a user changes one block in the chain, the change is visible to all participating computers. A hacker trying to break the system would have to change every block in the chain across all decentralized versions of the chain.

What is the blockchain consensus mechanism?

A consensus mechanism is a formula for a group of people without a superior central authority to reach decisions and ensure compliance with the agreement. Blockchain consensus algorithm refers to the process by which users or peers within a blockchain network reach a common agreement or consensus regarding the real-time state of the blockchain.

Consensus protocols allow blockchain networks to not only guarantee security within the distributed ledger, but also to achieve reliability and create trust between different notes. Consensus algorithms become an integral part of every blockchain app or DApps project within the blockchain.

A blockchain consensus mechanism is typically responsible for three things:

• These ensure that the next block in the chain is the only correct version of the truth.
• These prevent a malicious attacker from reaching 51% hashing power to take over the system and successfully fork the chain.
• They ensure the reliability of networks containing multiple nodes. This is one of the most important aspects to ensure network integrity. The most important element of the consensus mechanism is to ensure that users do not spend the same cryptocurrency twice (double-spending).

Other financial service providers, such as credit and debit card companies, do not operate a consensus mechanism, unlike blockchain companies, as the companies control the network. Every time a user uses a credit card, the system sends the information to a central database. Credit card users trust companies to protect both their data during transactions and the process of each order.

Because only the credit card company controls its entire network, it reserves the right to reverse or censor any transaction. In addition to the right to censorship and the inability to resolve disputes, most centralized databases are highly susceptible to the risk of hacking and corruption.

We are entering the era of blockchain and cryptocurrencies. It is now possible to perform reliable, immutable, and traceable peer-to-peer transactions within a decentralized network. Since there is no central or higher authority within such networks to enforce compliance with established rules, various types of blockchain consensus algorithms allow all participants within the network to agree on the rules and enforce the rules. Guaranteed to play according to.

Goal of blockchain consensus mechanism

The main goals of the blockchain consensus mechanism are:

#1.Unification agreement

Achieving a unified agreement is one of the main purposes of consensus mechanisms. The protocols built within blockchain’s decentralized network ensure that all data entered during the process is true and accurate, and that the status of the ledger remains up to date. As a result, users can conduct transactions without necessarily building trust with their peers.

#2.Create common economic incentives

Blockchain is a trustless system that regulates itself, so the interests of all participants must be aligned. In such situations, blockchain consensus algorithms reward those who toe the line and punish bad actors, while regulating economic incentives.

#3.Fairness and equity

Consensus protocols allow all interested users to participate within the network using the same basics. As a result, the decentralized and open source aspects of blockchain systems are justified.

#4.Removal of obstacles

The consensus mechanism method also ensures that the blockchain is consistent, reliable, and fault-free. This means that the system can always operate independently, even in the event of failures or threats.

Types of blockchain consensus algorithms: proof of work and proof of stake

There are numerous consensus algorithms within the blockchain ecosystem, and many more are currently in development. Therefore, every user and entrepreneur must understand the characteristics of different consensus mechanisms and know how to identify those that are inadequate. After learning the basics of blockchain consensus algorithms, discover the pros and cons of the two most popular consensus methods.

Proof of Work (PoW) and Proof of Stake (PoS) are the most widely used blockchain consensus methods. Both regulate the process by which peer-to-peer transactions are verified and added to the blockchain’s public distributed ledger without involving a central authority. Understanding the difference between PoW and PoS will make it easier to evaluate cryptos in your portfolio.

What is Proof of Work (PoW)?

Proof of Work consensus methods emerged in the early 1990s to combat email spam. The idea behind it was that the computer needed to perform a small amount of work before sending an email. This task should have been a simple task for someone sending one or two legitimate emails, but it required significant resources and computing power for someone trying to send a large number of emails. did. Bitcoin founder Satoshi Nakamoto was the first to apply digital money technology in the Bitcoin white paper.

a. blockchain order

You probably already know that a blockchain is made up of a series of blocks that represent a group of transactions arranged in chronological order. The first block in a proof-of-work based blockchain is hard-coded into the software and is called block 0 or the genesis block. The first block does not refer to the previous block, but all other blocks entering the blockchain must refer to the previous block. Each carries an updated copy of the ledger.

b. Energy use

The Proof of Work algorithm uses a competition to determine which of the participants (cryptocurrency miners) can adjust the ledger. Miners must use computational energy to be eligible to propose valid blocks according to the rules of the network.

Computers running Bitcoin software, known as nodes, verify transactions, prevent double spending, and decide whether a proposed block should join the chain. Bitcoin miners compete with each other for the chance to create new blocks by solving complex mathematical sums through a process called hashing. Mathematical problems are difficult to solve, but networks can easily verify the correct solution.

c. Participation

PoW consensus methods combine computational power and cryptography to build consensus and verify transactions recorded on the blockchain. Miners participating in the hashing process must generate correct answers to mathematical questions to be eligible to add new blocks to the chain.

Participating miners guess a series of pseudo-random numbers. This pseudo-random number, when combined with the information in the block and passed to the hash function computer, must provide a solution that matches the pre-set conditions by the algorithm.

Once an answer is obtained, the system broadcasts the winning hash to the network so other miners can verify its validity. When other miners verify the hash, the block is added to the blockchain, and successful miners receive rewards through block rewards.

d. Distribution of rewards

Anyone who mines a block that is recognized as valid within the network receives a block reward (usually a new cryptocurrency). For cryptocurrencies like Bitcoin, the blockchain systematically reduces the block reward amount after a specified number of blocks are created in order to keep the total amount of funds finite and deflationary.

What is Proof of Stake (PoS)?

The Proof of Stake (PoS) consensus method is a modified version of PoW that debuted in 2012. Rather than relying solely on computers competing with each other to create the correct hash, the purpose of PoS consensus protocols is to enable participation through ownership. of certain cryptocurrencies. Its purpose was primarily to address PoW’s high energy consumption for determining blockchain ordering.

The PoS algorithm uses a predetermined set of factors to pseudo-randomly select a node among the coin holders and propose the next block to the blockchain. In addition to signing and proposing blocks to the blockchain for verification, it is the role of selected nodes to verify the validity of transactions within the block.

a. blockchain order

Similar to the PoW mechanism, the PoS consensus method consists of a series of blocks arranged in chronological order. The first block in a PoS-based blockchain is also hardcoded into the Genesis Block software. Every subsequent block added to the blockchain must reference the previous block and retain a complete copy of the updated ledger. However, unlike the PoS method, participating nodes do not compete to be selected to add blocks. As a result, new blocks are typically forged or cast rather than mined.

b. Energy use

PoS-based blockchains are famous for using an energy-efficient system to determine who can propose new blocks and do not rely on high energy consumption or computing power. Proponents of the PoS consensus mechanism claim that it is an environmentally friendly mechanism in which individual nodes are assigned the task of creating new blocks rather than competing with each other.

Since PoW mining and PoS minting both require energy consumption, mining and minting nodes are incentivized to use the cheapest forms of power possible, and in most cases are powered by greenhouse gas sources such as coal. It is powered by renewable sources such as hydroelectricity, wind, and solar power rather than gas sources.

PoS miners only require an active internet source that requires a small amount of energy, whereas PoW miners require specialized hardware (GPUs), mining equipment, and other You will need to obtain an expensive device.

c. Participation

To participate in a PoS consensus scheme and have a chance of being selected to add a block to the chain, users must stake or lock a certain amount of blockchain tokens in a specific smart contract. Your chances of being selected as a participant are determined by the amount of cryptocurrency you stake.

If a user acts maliciously or violates the established rules, they may lose their stake as a penalty. The PoS algorithm employs several other decision factors to avoid favoring only the richest nodes. Some of them include pure randomization and the number of times a node has staked a coin.

d. Distribution of rewards

Similar to the PoW consensus mechanism, users who successfully propose a valid block will receive a block reward referring to the blockchain’s cryptocurrency. Nevertheless, since coin ownership determines the choice, some cryptocurrency exchanges offer staking services by placing stake on behalf of users in exchange for regular payments.

PoW vs. PoS: Where does the future belong?

Our verdict on proof-of-work and proof-of-stake blockchain consensus algorithms is that they both work differently to achieve the same objective. However, proof of stake is still relatively new to the market, so it may be unfair to pass judgment on which is the outright winner.

PoW is the traditional consensus mechanism in most proprietary blockchains such as Bitcoin and Ethereum. However, Ethereum is moving forward with the adoption of new PoS protocols to demonstrate the potential of new consensus methods.

The PoW consensus mechanism has stood the test of time and has been proven to work as a way to secure blockchains. However, it negatively affected network scalability and negatively impacted transactions. These days, individuals rarely have the opportunity to mine because large centralized mining organizations with vast computing power have taken over mining, making the associated costs unsustainable.

On the other hand, PoS algorithms are energy efficient and the network underneath them enjoys higher scalability and more efficient transactions. However, this mechanism provides less security for the cryptocurrencies staked by participants.

conclusion

PoS emerged to address the flaws inherent in PoW mechanisms, and of course achieved success in terms of energy efficiency. However, given that Ethereum is gravitating toward PoS while Bitcoin is sticking with PoW, both blockchain consensus algorithms are likely to exist in the near future.

You may also be interested in blockchain nodes.