Companies spend billions of dollars trying to ensure their various databases full of sensitive data are correct and hasn’t been tampered with. Meanwhile Bitcoin’s blockchain seems to have already solved this problem perfectly. So why is the Bitcoin blockchain immutable and could we bring this new technology to private company databases?
What Is A Blockchain?
To start with, a Blockchain is a distributed database, also referred to as a distributed ledger, that’s shared between many nodes on a network. They are most commonly used in cryptocurrency networks, but they have been used for other things too. The data stored in a blockchain is immutable, which means that it cannot be altered or changed.
In order to keep track of who owns what tokens or coins, cryptocurrencies use blockchain technology. This big database or file is constantly updated to show who owns what. For example it might say “Bill owns 1 bitcoin”.
Why Is Blockchain Immutable?
In order to properly explain why the Bitcoin blockchain is immutable we need to explain what a hash is and how blocks in the blockchain are structured.
Cryptography And The Hashing Process
Cryptographic Hashing or a hash function might sound complicated, but it’s just a special algorithm that takes in some data and outputs different data. In the case of bitcoin the specific algorithm that’s used is the Secure Hashing Algorithm 256 (SHA256).
For example the SHA256 hash of “hello” is:
This output serves as a digital signature for the original data.
While the math behind the hashing process is a little complex, the important thing to understand is that once you put any sort of data through a hashing process it’s virtually impossible to reverse.
The output is a seemingly random set of 64 numbers and characters regardless of how much input data you put in and even the slightest change in 1 bit of that original data will output a totally different and unique hash value.