Ever since the beginning of the revolutionary cryptocurrency Bitcoin by Satoshi Nakamoto, the markets have been on fire. For those seeking to learn new languages and technologies as a hobby or as a part of the profession, Bitcoin does present a unique opportunity in Blockchain.
But one has to note here without failing, Blockchain has surpassed its initial purpose and is now enroute to become one of the most transparent systems and perhaps even the most used in any future date.
But is Blockchain stable and as secure as they say?
While Blockchain may have some challenges, security is not one of them. Courtesy of the open-ledger system that it is. You may have wondered at one point about the name. Why is it called Blockchain? This is because of how the records are stored. New records are stored on top of old ones just like you might mount a building block upon another. The new record preceded by the older blocks or records. It all forms a chain structure and hence the name.
But how does Blockchain achieve security and transparency? How does it protect the system from being fooled into thinking that a record is valid when in reality it is quite opposite? To know the answers to these question, you need to have a basic idea about hashing.
Hashing means mapping or relating a certain data to another temporary data. You may have a set of characters, the hashed version of the characters would be a set of different characters. But there would always remain a certain rule to relate them both.
There are many algorithms used for hashing like SHA1, SHA2 and MD5 etc. All these algorithms hash a given input into a set of different characters which are unrecognizable. You put an input, say a paragraph through a hashing algorithm and out pops the hashed version of the paragraph bearing no resemblance to the input. Hashing is a one-way street.
How does it Work in case of Blockchain?
Now in Blockchain, every user keeps a track record of transactions. This record is regularly updated. When a user introduces a new transaction to the system, the user hashes it once or multiple time. This gives a unique output.
Now other users or nodes or clients do the same thing. They too run it on their respective machines. If the output matches then the transaction is termed as valid. If not, then it is rejected. This is a seemingly simple procedure that the Blockchain technology uses to distinguish between real transactions and fraud ones. It may look like inessential but the importance of this process becomes paramount when sensitive and valuable data, say, Bitcoins are introduced into the mix.