One of the Biggest Issues Facing Blockchain Is Its Lack of Ability to Scale
Here's what you need to know about the problems facing the technology backing Bitcoin and other cryptocurrencies.
In order for the world economy to continue to grow, we need to develop digital infrastructure to sustain the speed and volume in which we share information. Data infrastructure needs to be scalable and deployable as the needs of our digital era continue to evolve.
Even though blockchain is somewhat the “new kid on the block,” it has excited the world of business. According to a survey carried out by Gartner, 66 percent of the respondents said they believed that blockchain is a business disruption and 5 percent were willing to spend over $10 million on the technology.
Blockchain has many uses and implications; however, the first mainstream application we've seen is through cryptocurrency. But the initial design of cryptocurrencies was not built for widespread use and adoption.
For Bitcoin and Ethereum to compete with mainstream systems such as Visa and PayPal, they need to step up their game with their transaction times. As explained by crypto trading company Coindesk, "While PayPal manages 193 transactions per second and Visa manages 1,667 transactions per second, Ethereum does only 20 transactions per second while Bitcoin manages a whopping seven transactions per second. The only way that these numbers can be improved is if they work on their scalability."
Scalability obstacles created by mining
When dealing with Bitcoin and Ethereum, a transaction is granted only when a miner (the person whose computer processed the code behind the currency) puts the transaction data in the blocks they've mined.
Let's say Stephen wants to send Andrew 10 BTC (bitcoin). He will send the transaction data to the miners, the miner will then put it in their block and then the transaction will be completed.
However, as Bitcoin rises in popularity, this process becomes more time-consuming. Plus, there is the issue of transactions fees. When miners mine a block, they become gatekeepers of that block. In order for transactions to go through, users will have to pay a toll to that gatekeeper. This “toll” is referred to as a transaction fee. This fee creates issues when scaling because it creates an additional barrier.
What about Ethereum? In theory, Ethereum is supposed to process 1,000 transactions per second. However, in practice, Ethereum is limited by a cap of 6.7 million gas -- the amount of computational effort required on the receiver's side of the transaction -- on each block.
Here's how to understand what “gas” means. Stephen has issued a smart contract for Andrew. Andrew sees that the elements in the contract will cost X amount of gas. Accordingly, he will charge Stephen for the amount of gas that's used up. It's like letting your friend borrow your car and making them pay back the amount of gas that was used when they drove.
These issues haven't surfaced much yet, because there hasn't been widespread adoption of cryptocurrencies until recently. Ethereum exploded in popularity around December 2017 through a game called CryptoKitties (where users buy digital cats and raise them). The popularity of the game brought to fore the issue of scalability, as documented in this Mashable article.
Here are some terms you should know regarding the scaling of blockchain.
Sharding is the splitting of the block verification process and running of parallel subcommittees to collate the completed data. Zilliqa is a platform that utilizes sharding. It has been proven to handle 2,400 transactions per second with a goal to match Visa’s average of 8,000 transactions per second, according to The-Blockchain.
Perhaps most importantly, Zilliqa reacts efficiently to scaling needs as its throughput increases with its network size, as opposed to Bitcoin becoming clogged with transactions. With a node size equivalent to Ethereum, Zilliqa predicts it could handle twice the transactions of Visa per second.
When a platform drastically branches away from its initial platform direction, it is referred to as a "hard fork." Preceding the hacking of the decentralized autonomous organization on the Ethereum network (where $53 million of crowdfunded cryptocurrency was “stolen,” as reported by Bitcoin.com). Ethereum took a hard fork in order to reclaim the money and continued as Ethereum Classic, while the existing course maintained the original blockchain as Ethereum.
Bitcoin recently adopted a hard fork in its capped block size, which means that old and new software are incompatible with each other and renders the old outputs invalid. Bitcoin has already forked previously, such as with Bitcoin Cash, and there are more planned for this year.
The proposed Bitcoin hard forks will all incorporate SegWit (the Segregated Witness soft fork), which is software designed to solve transaction malleability but also improve the capped block size issue. Each block has a capped size that creates a finite amount of transactions to occur on each block.
SegWit increases the block size limit to 4MB, meaning a single block can hold the records of more than 8,000 transactions. However, although the block increase provides short-term respite in scalability issues, it will still eventually present the same restrictions once transactions have exceeded the limit.