Finality in Blockchain – A Security Guarantee or An Empty Promise?

One of the most notable and appreciated additions that blockchain technology has brought to the world is irreversible and unmodifiable transactions, meaning that once a transfer or operation is done, changes can’t be made to their terms. In layman’s words, finality guarantees that transactions aren’t alterable once finished.

There are numerous finalities on the blockchain, with most of them hinting at proof-of-work (PoW) systems, such as those underlying Bitcoin, Avalanche, and the Binance Smart Chain. Finality is obtained through a consensus mechanism, which depends on the choice of blockchain. Each utilizes different consensus algorithms, ranging from PoW to proof-of-stake (PoS) to the Practical Byzantine Fault Tolerance. Each model of finality is associated with varying levels of irreversibility and assurance when it comes to blocks and transactions. There’s more to finality than meets the eye; it is, by definition, an element that makes blockchain stand out from other technologies and fuels its popularity among players ranging from businesses to financial institutions.

For those who’ve ventured into blockchain transactions, the concept of “finality” might ring a bell. However, if you have yet to come across the term, starting with a brief explanation and proceeding with different finality types will help you expand your knowledge of the intricacies of blockchain. Here’s everything you need to know about this one-of-a-kind feature that blockchain for which blockchain is held in high regard and increasingly gaining ground across the world.

The concept of “finality” in blockchain was dissected.

Transactions for blockchain are like take-offs at airports; they continuously take place. However, many laypersons may think they’re only limited to financial matters. The truth is that transactions take all forms on the blockchain, such as ownership transfers or voting, occurring on more types of blockchain networks, like permissions, consortiums, private, or public. Given the high value of the belongings transferred, users seek the highest level of security, primarily translated to irreversibility or the lack of possibility to alter information.

Thus, finality is essential in blockchain consensus protocols, guaranteeing the level of protection sought, though it only sometimes occurs right away. A specific number of confirmations may have to be registered for the transactions to be considered done and finished. Furthermore, the speed at which this action takes place is essential because it determines the rapidity with which transactions are affirmed and added to the blockchain. The transaction confirmation timespan is directly associated with the finality provided by the used network.

A clarifying example would be that of a very probabilistic network in terms of achieving finality, such as Bitcoin. In this scenario, the time needed for transaction confirmation is influenced by the multitude of blocks attached after the transaction block. The more blocks are annexed, the lower the likelihood of transactions being reversed, which ultimately translates into a lengthier transaction confirmation time.

Generally, most cryptocurrency exchanges need less than an hour to confirm transactions with PoW assets like Bitcoin or the time taken for 3 to 6 blocks to be confirmed. In Ethereum’s case, the block confirmation process may take less or several minutes.

Finality in blockchain: Why should you care?

It stands to logic that one may wonder why they should grasp the finality concept since it’s intrinsically embedded and guaranteed by blockchain technology. However, given the complexities of this cutting-edge advancement, understanding some definitory elements can help those unfamiliar with the sector make better sense of it.

Finality is key to users’ high trust in the system, ensuring that their operations are alterable under no circumstance. However, it’s important to note that accomplishing this concept in a decentralized system like blockchain is challenging. Numerous factors must strike a balance to achieve this result, such as the network latency, the consensus system employed, and the security tools’ strength. Several types of finality can result, as you will see, which all depend on this selection of factors. Each model brings its own ups and downs, with the option chosen being ultimately made on the grounds of the desired results expected from the blockchain network.  

Several of the main types of finality are described

As stated above, more types of finality can be achieved, such as the following. In the blockchain realm, they all point to various levels of irreversibility and assuredness regarding adding blocks and transactions. Let’s throw light on them to discover which suits what action.

Probabilistic finality

Once transactions are done, this finality type grows with the number of blocks attached to the ledger. Simply put, the more blocks are annexed, the harder it is for the transaction to be altered or restored. For most protocols offering this model of finality, it’s advised to attach blocks after completing the transactions until they can be deemed finished.

Unconditional finality

Unconditional finality can pose difficulties when aimed for in decentralized systems because it needs a certain level of centralization or a specific consensus model to be achieved. Once the transaction is confirmed, the unconditional finality concept assures the final result, and the likelihood of undoing the action is zero.

Economic finality

This type of concept is frequently linked to proof-of-stake models, where nodes or validators need to grant a stake or a certain number of cryptos as collateral. This obligation prevents them from authorizing fake transactions because this misconduct would put them at risk of losing their stakes.

State finality

State finality is critical in applications like smart contract deployments, where the need for correctness is unquestionable.

This points to the blockchain’s entire state and goes beyond mere transactions. Once confirmed, such a state transaction can’t suffer modifications, alterations, or reversals.

Wrapping up

Block finality is one of the weightiest concepts in this ever-evolving tech realm. One of its main benefits is that transactions can never be changed, falsified, or reversed, giving users peace of mind knowing security is at its peak. Once transactions occur, there’s no way they can be tampered with, which is what users seeking reliable transfer methods find in blockchain technology.