Introduction To Blockchain 

"Understanding the bare-bones of the decentralized realm"

Topics:

• What is Blockchain.
• Why do we need it in today's world.
• Peer-To-Peer networks (P2P)
• Importance of Verification and Transparency

Hi, My name is Mubashir Ali Baig and this is my multi part series of understanding what blockchain is all about and what are some of the most important aspects that differentiate a decentralized network from the conventional centralized networks. I'll try my best to explain the above mentioned topics without going deep into the technical jargon.

What is Blockchain: By the standard definition: " A blockchain or "block chain" is a growing list of records in the form of virtual blocks." These blocks are linked together using some unique encrypted pointers called hashes. To simply put, it resembles to the linked  list data structure in which each node points to the next node using a pointer address which in the case of blockchain are called cryptographic hashes. But if we already have the linked list data structure then why re-brand it under the banner of blockchain?.

Well, there are some key differences which are as follows:

• Each block contains cryptographic hash of the previous block, a timestamp and transaction data.
• A blockchain is immutable which means the data stored on a block is resistant to any modification.
  
• A blockchain is managed by a peer-to-peer network for the use as a distributed ledger which we will discuss later in this post.

To summerize it, A blockchain can be described as a timestamped append only log.

Why do we need it?: To understand its need, we need to look around the existing technologies built over the conventional client-server architecture, in which a server machine acts as a single source of truth for the client side. The users data is bound to be stored somewhere in the world in the third party machines. Although, the conventional networking and storage resources have evolved massively but still it jeopardizes the privacy of users. Along with the privacy hazards, the data is mutable or worse it can be stolen or destroyed due to hardware failures. 

Considering the massive privacy breach events like the whole "Facebook Cambridge Analytica Fiasco", it has now become evident that we need to stop relying upon the middleman entities for the transactions whether it is monetary or personal data. Considering all of the above contingencies of the current networking architecture, a blockchain network removes the middleman through the peer to peer network topology in which every node is interconnected with other nodes with extremely strict measures of privacy by the use cryptography algorithms which we will discuss in the future posts. What i just described above can be encapsulated under the concept of Decentralization.

The Concept Of Distributed Ledger:

A distributed ledger is a database that is consensually shared and synchronized across multiple sites, institutions, or geographies, accessible by multiple people. It allows transactions to have public "witnesses". The participant at each node of the network can access the recordings shared across that network and can own an identical copy of it. Any changes or additions made to the ledger are reflected and copied to all participants in a matter of seconds or minutes.

Blockchain is also a type of distributed ledger in which all the peers maintain the record of whole network, thus providing the transparency to the system. I'll explain the importance of transparency and verification later in this post but first we need to understand the concept of peer to peer networks.

Peer To Peer Networks (P2P):

A peer to peer network is created when 2 or more computers are connected without having to connect to a central server machine as a gateway, this allows every peer to be a client and server at the same time. It is especially feasible to implement for the purpose of parallel and distributed computing using a message passing interface thus opening the doors towards rapid data sharing with negligible security flaws. Through peer to peer networking you can execute the tasks which require high concurrency of data. 

Since we are talking about blockchain and we know that it is managed over a peer to peer networks, so it does explain why the process of transactions is transparent and it makes it harder to breach the privacy standards with an extra layer of cryptography.

Importance Of Transparency And Verification: Let's talk about why the process of transparency and verification is very important in the blockchain realm. As we know that blockchain is a type of distributed ledger in which each node has the access of all the blockchain nodes, here's the catch if the these nodes don't have the access to the whole data then someone might create a malicious block and there would be no way to verify whether the transaction is organic and not malicious, keeping the record allows all the participants to examine the coming transaction and the fate of that transaction is decided by other nodes so that no particular node can have a supremacy over others, it is also important to understand that how each node can examine the coming transaction, it is because the transaction creator has to broadcast it over the network and each node thus compares and verify the information by cross checking it with their maintained record. However there are still ways to exploit this process but i'll save it for the next part of my blog series.

I hope i've conveyed enough concepts in the most simplest vocabulary, for any queries or to report any conceptual flaw in this blog, feel free to hit me up at 

email: mubashirbaig98@gmail.com or comment below.