Читать книгу The Bitcoin Big Bang - Kelly Brian - Страница 11

One of the first things I learned was that Bitcoin was known as a peer-to-peer network, which is fancy computer-speak for no middleman. The concept behind the technology is as old as commerce itself: cut out the cost of a middleman and you can offer a product cheaper. Business empires have been built on this concept, for example, the food co-ops of the 1970s in the United States were the first-generation Costco, BJ's Wholesale, and Sam's Club.

Peer-to-peer networks have a history of revolutionizing industries. Sean Parker's creation, Napster, is a great example of a peer-to-peer network that changed music. With Napster, music files could be shared among friends (peers) without having to go to Tower Records and purchasing the album. Once the album was purchased, your peer could make you a copy and walk it over to your house. This cumbersome exchange not only involved several middlemen; it also involved your getting off the couch. Napster cut out the middlemen and allowed you to share your favorite tune from the comfort of your home.

Of course, the middlemen were none too happy with Mr. Parker, and they launched a barrage of lawsuits to reclaim their turf. Eventually, the legal costs caused Napster to shutter, but not before it changed the music industry permanently. Many consider the single song file-sharing service to be a predecessor to Apple's iTunes. The recording industry was accustomed to selling entire albums chock-full of songs that few wanted to hear. What Napster did was illustrate that the consumer preferred à la carte music purchases, and Apple picked up on this demand. Napster may have changed how people shared music, but Apple changed how they purchased it. Even more, iTunes has changed the way music is recorded and released. Many may lament the death of the album, but Napster and iTunes have ensured that there is no turning back.

When thought of as a file-sharing service, Bitcoin it not too different than Napster. The files that are being shared are units of value rather than music. If you could find a grocery store that accepted music as payment for food, then Napster could become a currency like Bitcoin. Once again, it comes back to whether the file you receive (music or bitcoin) can be used to buy something else. As soon as the file can be traded for something else, it becomes a currency, and if by some miracle the rest of the world decides to accept music as payment, then the value of that “currency” will likely rise. Once something becomes a currency, a new level of security is needed.

The security of the Bitcoin technology is what makes it more suitable than Napster as a currency. At the heart of Bitcoin is a global ledger, or balance sheet, called the blockchain. This global ledger records every transaction that takes place with bitcoin. From the moment a bitcoin is minted, its every move is recorded, and it is this record that ensures bitcoins cannot be counterfeited. In order to create the blockchain, approximately every 10 minutes the Bitcoin software compiles all the transactions that have occurred into a file called a block. This block contains a reference to the previous file and is a record of every transaction that has ever occurred. When all the blocks are linked together, it forms a chain of blocks, thus the blockchain.

The security of Bitcoin depends on the process of linking all the transactions. Imagine if a one dollar bill were tracked each time it was used, from its printing to eventual retirement. Every pack of gum, soda, flower, or toy that was ever bought with that dollar would be recorded. If a counterfeiter made a copy of this dollar bill, it would contain a record of the rightful owner, and when he attempted to spend it, the built-in security would disallow the transaction. A counterfeiter would have to go back and convince each merchant that the transaction never took place. In essence, a counterfeiter would have to change every single transaction prior to making the copy.

Bitcoin's solution to the counterfeit problem is the combination of the blockchain and miners. As more transactions are added, the blockchain makes it virtually impossible to change prior transactions. The miners are charged with confirming that the bitcoin being transferred is not counterfeit. The act of mining for bitcoins involves using powerful computers to solve a complex mathematical equation. The answer to the equation contains a key that verifies all the previous transactions. If this key does not match the previous transactions, then the miners know the bitcoin is counterfeit.

In very simple terms, this is how a bitcoin transaction works: If Keith wants to send a bitcoin to Alan, he must broadcast that message to the Bitcoin network. The miners listen for this message and then use supercharged computers to ensure that Keith is the rightful owner. Once they verify Keith's ownership, they allow the transaction to occur and record it in the blockchain. For their work, the miners are rewarded with free coins called a coinbase – currently, for every group of transactions (block) that a miner verifies, the miner receives 25 bitcoins.

As we continue our journey to Bitcoin Enlightenment, we will wrestle with several more terms that may challenge some and enthrall others. For now, the most important terms to remember are peer-to-peer network, blocks, blockchain, and miners. The Bitcoin peer-to-peer network allows users to transfer value; these transactions are stored in files called blocks; these blocks are linked together to form a blockchain; and miners solve a mathematical equation that proves ownership of a bitcoin.