Simplifying Blockchain – Part 3

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Let’s continue the elements and components we started to talk about in part 2.

4- Blocks

Blocks are the basic element in the blockchain. Block contains records of the past transactions and has segments reserved to save the data for future transactions.

So, the block is a past and future transaction, blocks are connected together through the chain. every time transaction happens and the hash code is solved in the precious chain, it is a chance of new block birth.

This is how blockchain is connected in a tight relation. All blocks communicated with each other to perform proof of authenticity. When one block is manipulated for any reason, the other blocks gather themselves and do one of common blocks task, which is VOTING. In the voting process, all blocks verify whether the transaction s in the odd block is verified or not. If not, they will update it with the right transaction. That’s what makes blockchain immutable and cannot be broken.

5- Hash

Hash is one of the common terminologies when we are talking about blockchain. Hashing -in general- is about to transform or generate a data of any length into a string of a fixed size by specific algorithm. This algorithm is a one-way cryptographic function as the original data cannot be retrieved via decryption.

But, how actually hashes work?

Usually, hash takes an input of variables to return it into output of a fixed length. A cryptographic hash combines this capability with security properties.

Let’s do an example to show a way of hashing.

My name is “MUHAMMAD ADEL”, I am going to use “Numerlogy” technique in this example. It means that I will replace each letter of my name with a correspondent number, like:

A=1, B=2, C=3 … etc

So, my name after conversion would be:

MUHAMMAD ADEL

13 21 8 1 13 13 1 4 1 4 5 12

You can use some online tools to do so if you have a problem, like this website.

Well, The next is my choice, which I will assume that it is my algorithm. I will combine all numbers together by adding them. Like:

13+21+8+1+13+13+1+4+1+4+5+12=96

Next, I will add the two digits again, Like:

9+6=15

Adding again.

1+5=6

So, 6 is the corresponding number to my name. The fact that if we both agree to the methodology, my name will equal 6 forever. Another fact that, this process is irreversible. It means that I will not be able to get name from just a letter. It is always one way cryptographic function.

Back to blockchain, we can see that every transaction is recorded in a block by its hash for verification. If transaction happened with my name and this hash is recorded with digit “6”, so, we are all in the chain can approve it…..for ever.

This is also defined the immutability of blockchain. it cannot be manipulated. since all blocks in the chain already has the hash, so they can always vote for the right transaction (as we talked before).

6- Nonce

It is an abbreviation for “number only used once,” which is a number added to a hashed block in a blockchain. It is the 32-bit number generated randomly only one time that assists to create a new block or validate a transaction. It is used to make the transaction more secure.

It is hard to select the number which can be used as the nonce. It requires a vital amount of trial-and-error. First, a miner guesses a nonce. Then, it appends the guessed nonce to the hash of the current header. After that, it rehashes the value and compares this to the target hash. Now it checks that whether the resulting hash value meets the requirements or not. If all the conditions are met, it means that it is granted the block.

Elements and components are not exclusive to those 6 components, a lot of elements added over time with more and more details. We may see them in the next parts.

Let’s move the the next part which is, why we do that? why we use blockchain over traditional systems?