Not a day goes by without multiple news stories about cryptocurrency. Numerous cryptocurrencies are active in the marketplace but the oldest and most well-known is Bitcoin. Cryptocurrencies, like Bitcoin, all rely on the foundational technology known as Blockchain. Cryptocurrencies are disruptive and have created a great deal of excitement, however, the Blockchain technology they are based on promises to revolutionize any industry that relies on big data. Some have said that Blockchain technology will transform our lives the same way the Internet has over the last several decades. So, what exactly is Blockchain technology?
At its heart, a Blockchain relies upon a system of “ledgers,” which is certainly nothing new. Ledgers have been around since clay tablets were used to record financial transactions. Double entry accounting is based on permanent ledgers where new entries are added, and previous entries are left unmodified. Each transaction builds upon previous transactions. Blockchain technology takes a simple ledger to a whole new level, one that is completely decentralized. A Blockchain ledger system is distributed over a peer to peer network. Everyone in the Blockchain network has an instance of the same identical ledger. Rather than relying on one trusted entity to maintain the ledger, all participants have a validated record of every transaction. Transactions do not have to be financial in nature; they can be any digital data. Financial transactions, medical records, retail inventory, anything of value can be tracked in a distributed ledger via Blockchain technology.
Blockchain stores information in batches called “blocks.” These blocks are linked together in a chronological order creating a continuous “chain” of information. If you need to make a change in a previous block of information you do not overwrite it, you simply add a new block with the correct data. The new block records that “X was changed to Y;” all renditions of the chain of data are kept intact and distributed to everyone in the Blockchain. This is a nondestructive way to track data changes over time similar to the centuries-old general financial ledger. The big difference is no one entity is in control of the master ledger, everyone in the peer to peer Blockchain network has the same complete “master” ledger. In addition, each block contains a “hash” which is essentially an electronic fingerprint unique to that particular block. As blocks are added to the chain, they include their own hash as well as the hash of the previous block. Tampering with or changing the data changes the hash of that block. This ensures that data cannot be modified or changed on any one node in the computer network. Combination of immutability and the distributed nature of the Blockchain creates trust in the data without a central authority required.
Before a new block of information can be added to the chain, a few things have to happen. First, to create the block, a cryptographic puzzle must be solved by the initiating computer. Next, the computer that solves the cryptographic puzzle shares the solution with all the other computers within the Blockchain network. This process is called “proof of work.” The network of computers will then verify this “proof of work” and, if it is correct, the block will be added to the chain permanently. The verification process works by consensus, requiring a majority of the computers on the network to validate the information before it is added to the Blockchain. Combining a complex math puzzle with the verification by numerous computers ensures every block on the chain can be trusted. Trust in the data is fostered by the distribution of transparent peer-to-peer information, without a central keeper of data.
By establishing trust in the data, Blockchain technology removes intermediaries from the data verification process. Many transactions today require a trusted intermediary such as an attorney or financial institution. We rely on these intermediaries to keep our information confidential and to verify the information of the other person involved in the transaction. As an example, title companies verify the “chain of title” on a piece of real estate prior to transfer. If the verified information was available in a Blockchain network, a history of all transfers of title and other property rights would be instantly available and verified as accurate. Title companies serve market participants by reducing risk, but they do so at a cost of time and money. Removing intermediaries and relying on trusted data would greatly reduce transaction time and cost while also controlling risk. Blockchain provides a trusted interaction with data completely changing the way we access, verify and transact with other parties.
Blockchain technology is currently in its infancy. It has been widely deployed by cryptocurrencies and its use in this sector has demonstrated some of its weaknesses. The largest cryptocurrency, Bitcoin, has an enormous distributed ledger. Every transaction since Bitcoin’s inception is included in the Blockchain that is distributed globally. Since Bitcoin is a monetary transaction, very few data points are required to be added to each block. In spite of the small amount of data, each distributed ledger has grown to gigabytes of information. Bitcoin is demonstrating that a broad public Blockchain has scalability issues.
The Bitcoin Blockchain, because of its size, can only process approximately 7 transactions per second. Compare that to approximately 20,000 transactions per second MasterCard can process. Time to verify a transaction is prohibitive by modern standards. Imagine ordering your favorite coffee from your local barista and trying to pay with Bitcoin; it might take 30 minutes to complete the transaction! In addition to the slow verification process, the energy costs of maintaining a globally distributed network are staggering. Forbes Magazine reports that global Bitcoin Blockchain consumes enough energy to power a country like Switzerland each year or 1.5% of the energy consumption in the United States. Most of this energy is a result of the proof of work calculations, essential to the distributed ledger.
Technology advances will eventually solve some of the weaknesses of Blockchain and overtime, Blockchain will change the way we do business. Trusted data sources that do not require intermediaries in transactions will disrupt many industries including the real estate industry. In a future article, I will address how Blockchain is being used and might be used in the real estate industry. As with any application of technology, there are tremendous benefits and unintended consequences. The real estate industry is entering the era of big data and Blockchain technology will be a part of how we interact with that data in the future.
If you would like to submit an article to Appraisal Buzz, please contact us at firstname.lastname@example.org.