Blockchain 101

A Blockchain Guide For Beginners

Blockqode

This guide is a brief introduction to the core fundamentals of blockchain technology, no matter if you don’t have technical knowledge. 


“Let's try to secure everything.” - Nick Szabo

If we need to explain Blockchain by what says the computer scientist Nick Szabo on that quote we can define blockchain by two important things of this technology (Immutability, and Transparency).

Those 2 are part of the valuable things the ‘Blockchain’ brings us and probably one of the reasons is taking many industries by storm.

Let’s start learning what is Blockchain.


Blockchain GENESIS

We are not talking about ‘The Genesis Block’ but the origins and conception of the Blockchain technology.

Who Invented The Blockchain?

The answer to that question is still unknown by many sources but we will describe it in a simple straight to the point way.

1991

19 years ago the term was first described as a cryptographically secured chain by Stuart Haber and W. Scott Stornetta who were part of a group of researchers that wanted to create a tool to timestamp digital documents.

This can tell you that some source knowledge on Blockchain is based on their research from 1991.

2008

The year when the Bitcoin: A Peer-to-Peer Electronic Cash System white paper appears online.

If you search on Google or any other search engine it points out as the creator of the white paper and Bitcoin project a person named Satoshi Nakamoto or says that it can be a group of persons with that name as their alias or pseudonym.

On the white paper, it’s mention Bitcoin, the first Decentralized Application (Dapp) that used the Blockchain. The implementation was to serve as a public transaction ledger for the Cryptocurrency ( digital asset that is used as a medium of exchange ).

What the proposal of Satoshi Nakamoto brought was the problem of the double-spending where there’s no need for a trusted authority or central server for the transaction.

Satoshi Nakamoto brought with Bitcoin a decentralized peer-to-peer payment network and set the scene for a decentralized network, with the underlying technology called Blockchain to keep a record of the transactions.

Nakamoto was the first to conceptualize the Blockchain with the Bitcoin white paper.


BLOCKCHAIN

What Is Blockchain?

A blockchain is an immutable time-stamped series record of data that is distributed and managed by a cluster of computers.

A system of recording information in a way that makes it difficult or impossible to change, hack or cheat. Essentially a digital ledger of transactions that is duplicated and distributed across an entire network of computer systems.

Blockchain is a type of Distributed Ledger Technology (DLT).

A DLT is where transactions are recorded with an immutable cryptographic signature called a hash.

These transactions are contained in blocks of data and each new block includes a hash of the previous one, chaining them together.


How Blockchain Works?

We are going to take Bitcoin as an example of how the blockchain works.

Bitcoin is the first one to use Blockchain technology on the exchange of digital transaction assets in the network.

The Bitcoin uses cryptography instead of third-party (middle-man) trust for two parties to execute transactions over the internet.

Each transaction it’s protected through digital signature.

On the decentralized network, the users are connected in a peer to peer connection means there is no central point of control and the transaction is cryptographically secured.

The database is managed autonomously where allows the participants to use a peer-to-peer network and a distributed timestamp server.

A Blockchain in simple terms is a chain of data blocks with a cryptographic hash of the previous block, a timestamp, and transaction of data.

Understanding The Byzantine Generals' Problem

The real challenge being solved on the blockchain is a general solution to the Byzantine Generals' Problem.

The Byzantine Generals' Problem is a 1980s dilemma in which an army can be thought transactions and the enemy city can be thought of as any man in the middle. The armies generals need to agree on an exact time to attack because the city can withstand the attack from only one army.

It’s simply a consensus-making in a system where communication channels cannot be trusted.


Why Blockchain Is Important?

Blockchain gives us Immutability, Transparency, and Decentralization for the transaction of data, and does not allow modification of the transaction records once updated in the ledger.

The network uses consensus to reach an agreement regarding the transactions in the network and use cryptography for the privacy of the data via a hashing.

  • Immutability

    Blockchain maintains a record of the transactions on a trustless peer-to-peer network and transactions are packed into blocks to be added to the blockchain through a consensus.

  • Transparency

    A transaction is settled between peers, then miners on the network create a block, and the data will be stored. A proof-of-work is validated to be included in the blockchain.

    There is a copy of all the transactions on each node in the network with a hash and then is included in the group of blocks. Transactions are public and viewed by all the nodes in the network.

    Security is provided because is verified by the miners in the network and is cryptographically protected.

  • Decentralization

    One of the most important things that bring the Blockchain technology is a decentralized network. There is no central authority to settle the transaction between peers (no middle-man).

    The removal of the middle-man gives us fast settlement time and lower transaction fees.

In a Centralized Network, there is a centralized point, where all data need to pass through a server before goes to all the nodes.

A Decentralized Network, on the other hand, relies on a peer-to-peer network built on a community of users where no one is in control.


TYPES OF BLOCKCHAIN

Let's explain the different types of blockchains.

The Blockchain started as public with Bitcoin and Ethereum, but the public blockchain is not the only one.

Ther are other types of blockchains that are a combination of public/private and permissionless/permissioned that have been created fitting a specific set of use cases.

Public Blockchain

A public blockchain is the permission-less distributed ledger technology where anyone can join and do transactions and no one has control over the network.

Anyone can access public blockchain if they have an internet connection and It is a non-restrictive version where each peer has a copy of the ledger.

Private Blockchain

A private blockchain can be defined as a closed permissioned blockchain that is under the control of an entity.

Private blockchains are for privately held companies or organization that wants to use it for internal use cases.

Consortium or Federated Blockchain

This is a Blockchain semi-decentralized that is managed by more than one organization.

It is a public/private blockchain with aspects that are made public, while others are kept private.

The consensus procedures in a consortium blockchain are controlled by the preset nodes and give the authorized transactions right to just a few users


Here we conclude our first and brief introduction of Blockchain.

We hope you have now a more clear understanding of Blockchain and how it works the fundamentals of the technology.

This is the first one of many Blockchain guides we are going to published on the Blockqode newsletter.

We are going to talk about all aspects of blockchain getting you from beginners to advanced development with our guides and tutorials.

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