While Bitcoin has been recognized as a modern technological advancement in the world of finance, recently, more attention has been paid to the technology behind it. This technology is known as blockchain, a ledger or record of facts. These facts can stem from terms of a contract to monetary transactions and other verification records.
The blockchain consists of several computers (nodes) in a peer-to-peer network. At every point in time, the members of this network hold the exact same copy of the blockchain which is constantly updated. Decentralized, peer-to-peer networks are not new and have been in existence for a long time. One prominent example is BitTorrent, a system that allows users to share files between each other.
How does Blockchain Technology work?
Each block on a blockchain consists of several transactions in cryptocurrency, carried out by several users. They serve as batches of processed information, tied together chronologically. A group of people commonly referred to as miners, listen for transactions and collect them.
After collecting them, they solve a complex cryptographic puzzle to find a solution known as a proof of work. The first miner to solve the puzzle broadcasts the new block bearing the proof of work to the network which verifies the validity of that block and adds it to the blockchain. The entire process takes about 10 minutes, and whenever a block is added to the Bitcoin blockchain, a fixed reward is paid out to the miner.
Once a block has been added to the blockchain, it cannot be edited, and any changes have to be re-written in a separate block. To illustrate this point, with the use of a physical ledger, if a transaction is recorded and something about the transaction has changed, it would be a better option to write a new entry in the ledger, instead of canceling the transaction.
What are Blockchain Forks?
Just as software applications get system updates, it's possible to update a blockchain to include changes to the way it operates. Bitcoin usage is guided by software known as the Bitcoin protocol. It specifies vital principles of blockchain operation such as the size of blocks, mining process, and other technical information.
In some cases, Bitcoin developers along with miners decide to make changes to the way the blockchain is operated. Unfortunately, these changes are not always agreed upon by everyone. The result is that a group of users and miners form a new blockchain branch known as a fork. A fork can either be ‘hard’ or ‘soft’ and maintains the history of the original blockchain up until the block on which the fork occurred.
Hard Fork versus Soft Fork?
In the case of a soft fork, the new branch is backward compatible with the old one, just like the way a Microsoft Word 2016 document can be opened in Microsoft Word 2009 application because it's backward compatible. However, there are features of the soft fork that won’t work on the original blockchain. Hard forks, on the other hand, are not compatible with the original blockchain. Users on the old blockchain will no longer be able to interact with users on the new one.
Due to several issues, especially the size of blocks, several Bitcoin hard forks have been made. The most notable one— Bitcoin Cash— was forked on August 1, 2017. While the size of blocks in the original Bitcoin blockchain is 1MB, Bitcoin Cash has blocks the size of 8MB. Some miners argue against the move, citing reduced fees per transactions since users no longer have to pay high fees for priority mining. Other miners support the move saying that miners can now earn more in fees since there will be eight times more transactions on each block.
Users who had BTC were given the same number of Bitcoin cash tokens as long as their coins were not held on exchanges and their keys were available. So, if a user had 50 Bitcoins on the original blockchain, then they would also have 50 Bitcoin Cash after the split. Forks have since become a way to implement new properties and functions to the initial open-source Bitcoin blockchain design. Other notable Bitcoin forks are Bitcoin Gold and Bitcoin Unlimited.
What are the Limitations of Bitcoin Blockchain Technology
While blockchain technology may inspire awe and excitement in the minds of the public, it has its flaws and complications which make its mainstream adoption for payment difficult. The following are limitations of the Bitcoin blockchain explained in detail.
It takes roughly 10 minutes to confirm a single transaction on the Bitcoin blockchain. As the user base continues to grow, it may take longer to carry out simple transactions. For example, it would not be feasible to pay for a coffee using Bitcoins as it would take 10 minutes to confirm a single payment and even more time if there are network problems or confirmation errors.
Another limitation of blockchain is the issue of scalability. The slow confirmation speeds and current technological structure of blockchain would make scalability a herculean task. This is especially problematic because the number of Bitcoin users is estimated to reach 200 million by 2024.
Each of those users may have several transactions to confirm at different times or simultaneously, and each block only takes approximately 2,400 transactions. At 2,400 transactions in 10 minutes, there is a possibility that transaction queues will pile up, making the process tiresome. Such numbers may completely overwhelm the system.
Transaction fees act as incentives for miners to add a user’s transaction to the block they're currently mining. The fee is usually a token amount, but in some cases, problems can arise. Since Bitcoin can be broken into eight decimal places, it's possible to make micropayments using the cryptocurrency. These micropayments can be less than the mining fee, and this constitutes a loss to users who have to make several micropayments in a short period.
Also, while mining is open to anyone, only a few people can afford the time and equipment it takes to mine Bitcoin. As a result, small groups often merge to form mining pools. The most dominant pools are based in China, and most of the computation power necessary for adding new blocks is concentrated between just two mining pools. This has somewhat made mining a centralized process.
Although blockchain has been proven to be secure for conducting transactions, there is speculation of its vulnerability in the face of a 51% attack. Simply put, blockchain works on the principle that if there are several conflicting versions of a blockchain being broadcast by miners, the most valid one is the longest, i.e., the one with the most work done.
If a user decides to include a double spending transaction (spending a digital token more than once), they would need to have control over 51% of the total mining computational power. This way, such a user can overpower other miners and have their version of the blockchain added to the network. For now, that problem hasn’t arisen, but theoretically, a quantum computer would be able to provide enough power to achieve this deed. Double spending can cause inflation and destroy the integrity of the blockchain.
This article is first seen on MintDice