Bitcoin vs. Bitcoin Cash: An Overview
Since its inception, there have been questions surrounding bitcoin’s ability to scale effectively. Transactions involving the digital currency bitcoin are processed, verified, and stored within a digital ledger known as a blockchain. Blockchain is a revolutionary ledger-recording technology. It makes ledgers far more difficult to manipulate because the reality of what has transpired is verified by majority rule, not by an individual actor. Additionally, this network is decentralized; it exists on computers all over the world.
The problem with blockchain technology in the Bitcoin network is that it’s slow, especially in comparison to banks that deal with credit card transactions. Popular credit card company Visa, Inc. (V), for instance, processes close to 150 million transactions per day, averaging roughly 1,700 transactions per second. The company's capability actually far surpasses that, at 65,000 transaction messages per second.
How many transactions can the bitcoin network process per second? Seven. Transactions can take several minutes or more to process. As the network of bitcoin users has grown, waiting times have become longer because there are more transactions to process without a change in the underlying technology that processes them.
Ongoing debates around bitcoin’s technology have been concerned with this central problem of scaling and increasing the speed of the transaction verification process. Developers and cryptocurrency miners have come up with two major solutions to this problem. The first involves making the amount of data that needs to be verified in each block smaller, thus creating transactions that are faster and cheaper, while the second requires making the blocks of data bigger, so that more information can be processed at one time. Bitcoin Cash (BCH) developed out of these solutions. Below, we'll take a closer look at how bitcoin and BCH differ from one another.
- Bitcoin is limited by transaction processing time, an issue that has caused rifts between factions within the bitcoin mining and developing communities.
- Bitcoin Cash was started by bitcoin miners and developers concerned about the future of the bitcoin cryptocurrency, and its ability to scale effectively.
- While bitcoin blocks are limited to 1 MB, BCH blocks are up to 32 MB.
In July 2017, mining pools and companies representing roughly 80 percent to 90 percent of bitcoin computing power voted to incorporate a technology known as a segregated witness, or Segwit This fix makes the amount of data that needs to be verified in each block smaller by removing signature data from the block of data that needs to be processed in each transaction and having it attached in an extended block. Signature data has been estimated to account for up to 65 percent of data processed in each block, so this is not an insignificant technological shift.
Talk of doubling the size of blocks from 1 MB to 2 MB ramped up in 2017 and 2018, and, as of February 2019, the average block size of bitcoin increased to 1.305 MB, surpassing previous records. By January 2020, however, block size has declined back toward 1 MB on average. The larger block size helps in terms of improving bitcoin’s scalability. In September 2017, research released by cryptocurrency exchange BitMex showed that SegWit implementation had helped increase the block size, amid a steady adoption rate for the technology. Proposals to both implement Segwit and double the block size were known as Segwit2x.
Bitcoin Cash is a different story. Bitcoin Cash was started by bitcoin miners and developers equally concerned with the future of the cryptocurrency and its ability to scale effectively. However, these individuals had their reservations about the adoption of a segregated witness technology. They felt as though SegWit2x did not address the fundamental problem of scalability in a meaningful way, nor did it follow the roadmap initially outlined by Satoshi Nakamoto, the anonymous party that first proposed the blockchain technology behind cryptocurrency.
Furthermore, the process of introducing SegWit2x as the road forward was anything but transparent, and there were concerns that its introduction undermined the decentralization and democratization of the currency.
In August 2017, some miners and developers initiated what is known as a hard fork, effectively creating a new currency: BCH. BCH has its own blockchain and specifications, including one very important distinction from bitcoin. BCH has implemented an increased block size of 8 MB to accelerate the verification process, with an adjustable level of difficulty to ensure the chain’s survival and transaction verification speed, regardless of the number of miners supporting it.
In 2018, the maximum block size for BCH was increased 4x to 32MB, but actual block sizes on Bitcoin cash have remained only a small fraction of the 32MB limit.
Bitcoin Cash is thus able to process transactions more quickly than the Bitcoin network, meaning that wait times are shorter and transaction processing fees tend to be lower. The Bitcoin Cash network can handle many more transactions per second than the Bitcoin network can. However, with the faster transaction verification time comes downsides as well. One potential issue with the larger block size associated with BCH is that security could be compromised relative to the Bitcoin network. Similarly, bitcoin remains the most popular cryptocurrency in the world as well as the largest by market cap, so users of BCH may find that liquidity and real-world usability is lower than for bitcoin.
The debate about scalability, transaction processing, and blocks has continued beyond the fork which led to Bitcoin Cash. In November of 2018, for example, the Bitcoin Cash network experienced its own hard fork, resulting in the creation of yet another derivation of bitcoin called Bitcoin SV. Bitcoin SV was created in an effort to stay true to the original vision for bitcoin that Satoshi Nakamoto described in the bitcoin white paper while also making modifications to facilitate scalability and faster transaction speeds. The debate about the future of bitcoin appears to show no signs of being resolved.