Blockchain Development and Programming Tutorial for Beginners
Blockchain has already had a huge impact on the development of all spheres of human activity; however, it still remains insufficiently developed for adoption by governments.
Let’s consider the main points a beginner should be aware of before starting to develop blockchain.
How Does Blockchain Work?
Blockchain is a set of blocks containing certain information. They follow one another, forming a chain of blocks. Given that blockchain is an open, distributed ledger, every user can see the created and executed blocks. Moreover, every user’s computer becomes a server, enforcing the blockchain’s work.
As the picture shows, before money reaches its addressee, the transaction must be verified by other users. That’s why any action on the blockchain can be tracked. This is the point where nodes should have their explanation.
Nodes are replicas that participants of the network use to store information on the ledger. For example, if there are ten transactions executed on the blockchain, each of the five nodes has to keep a record of those ten transactions.
Where does the currency come from? Well, some nodes perform mathematical calculations in order to get a reward in coins. This process was originally called mining. Nodes that solve NP-class problems are called miners.
Types of Permission
There are two types of blockchains: a public one and a sidechain (private). On the public blockchain, every node that is registered in the network has access to every piece of information kept on the ledger. What distinguishes a private blockchain from the public one is that a sidechain is a microworld made up only of nodes participating in the agreement. Usually, private blockchains are created by several companies that share confidential information.
Types of Consensus
blockchain was created as a payment tool enforced by cryptocurrencies. However, in order to execute transactions, nodes must come to a consensus. Originally, on the Bitcoin blockchain, Satoshi Nakamoto established the proof-of-work consensus type, which means that a transaction is sent only after certain goods or services have been provided.
Let’s see the full list of consensus types:
- Byzantine Fault Tolerance (BFT)
- Federated Byzantine Agreement (FBA)
- Proof of Authority (PoA)
Proof-of-Work Consensus Type
As mentioned previously, users are able to execute transactions only after verification by other nodes. This is one of the peculiarities of blockchain that allows the elimination of intermediary parties.
Proof-of-Work consensus comes into action when node A (the sender) confirms that the required action was taken by node B (the receiver). This allows the money to be sent.
Proof-of-Stake Consensus Type
This type of consensus algorithm allows a choice of the next node to create, and executes a block by means of judging its balance. Nodes with a wallet with a higher balance are more likely to receive a reward in coins.
The disadvantage of the Proof-of-Stake consensus type is that the rich get even richer; and for users with a low balance, it becomes very hard to compete with the so-called “giants.”
Byzantine Fault Tolerance Consensus Type
Following the Byzantine Fault Tolerance consensus, the users agree that after the block is created it should be verified or nor by means of voting. The node that votes first is considered as a leader, and others should follow or decide to decline the block.
The block will be verified or not only after approximately 60% of the nodes in the network have made their decision.
Federated Byzantine Agreement Consensus Type
The only point differentiating the Federated Byzantine Agreement consensus type from the previous one is that there is no need for 60% of the nodes to vote. The percentage may be less.
Proof-of-Authority Consensus Type
This type of consensus is quite unnatural to the idea of a decentralized platform, due to the fact that decisions on block validation may be changed or canceled by a node possessing special rights.
A smart contract is a concept coined by Nick Szabo, a famous cryptographer. He realized that the distributed ledger could be used for running digital assets. This would act like a legal agreement that eliminates the need for third parties. It is secured by a crypto-signature, and can be supervised by the network.
To describe the internal process in a nutshell, we will draw a parallel between a smart contract and a vending machine. When you want to set up any kind of legal agreement, you normally go to a lawyer or a notary, pay them money, and have to wait, as you’ve become a victim of paper bureaucracy.
With smart contract technology, all you need to do is drop the crypto-funds, document, or whatever you need into the vending machine (i.e., ledger). The legal nature of the smart contract is similar to an ordinary agreement; rules and penalties are defined, as well. What makes smart contracts more significant is the automated process enforcing those obligations.
How Smart Contracts Are Used
There are plenty of files that implement smart contracts in order to save time and money. Let’s consider the giants on the market.
It is common knowledge that the voting system is rather complicated and contains many nuances. Smart contracts are more than capable of running this type of logic and keeping up with all the rules, thereby providing heightened security and scalability. Votes are protected via crypto-signature, which guarantees data immutability and full transparency. Because hacking would require inconceivable computer power, smart-contract technology is highlighted as a robust system.
Blockchain power is generated by the participation of the nodes. Ordinarily, business requires step-by-step verification of internal processes, and may require some time to be confirmed. In comparison, blockchain distribution is a breath of fresh air.
In today’s fast-growing world, it’s hard enough to keep up with all the new technologies and updates. Smart contracts considerably ease this process.
Google is working on a new concept in the sphere of automotive and transport: smart cars. At this stage, smart contracts come into action to provide logging and tracking of all events during self-driving. Using this data, insurance companies will be able to charge rates to customers based on existing conditions.
Smart contracts also allow you to raise more money. Traditionally, if you wanted to become a landlord, you had to pay a third party: the newspaper or rental platform. Blockchain provides the opportunity to get rid of all this by encoding the rental agreement into a smart contract. In the blockchain, all participants profit.
Programming Languages for Blockchain Creation
Let’s start with a language comparable to reading English: Python.
Is one of the most frequently-used programming languages. It is famous for its simplicity and the availability of lots of libraries. Python’s abundance also provides a huge number of guides and templates.
Pros and cons:
- Availability of many libraries
- Does not fully support parallel programming
- May not be enough for complex tasks
Is the father of a vast number of programming languages. Created in 1982, it became one of the most popular languages of its time, and remains so today. C++ features manual memory management. Under the hood, it’s an object-oriented language, but it allows writing in a functional style, too.
Pros and cons:
- One of the best choices for complex solutions
- Strict types
- Very fast
- Knowledge of C++ opens the road to almost every other language
- It can be rather complicated for a novice to start writing on it
- Manual memory management causes lots of headaches, especially when you’re writing a distributed solution
Is a strongly-typed interpreted programming language, designed in such a way that it’s able to check errors. One advantage is that the Java Virtual Machine allows the reading of apps written in Java in any system.
Pros and cons:
- JVM is considered one of the most powerful VMs
- Supports a lot of libraries
- Rather slow in comparison with C++ due to automated memory management
Pros and Cons:
- Simple syntax
- Availability of libraries
- Easy to learn
- Doesn’t require a lot of programming experience
- Dynamic types
Platforms for Blockchain Building
A multitude of projects provide the opportunity to create your own blockchain (private) or to develop the public blockchain. In this article, you will get acquainted with some of these.
Ethereum is a decentralized platform run by Ether, its cryptocurrency. Mostly, the Ethereum blockchain serves as a tool for DApps creation.
Ethereum was the first platform to introduce smart contracts, and remains the most popular among DApp and ICO launchers.
An important point to mention is that smart contracts on Ethereum are predominantly written in the Solidity programming language.
The R3 blockchain-based consortium of more than 200 companies has presented this service, which allows the creation of DApps on top of the Corda Platform. Unlike the Ethereum platform, Corda uses the Java programming language.
In the age of constant appearance of new technologies, it seems odd to look back at the times when blockchain was something brand-new and scary to dive into.
Now that several industries have implemented blockchain technology and obtained benefits from it, every single company is considering the advantages blockchain could bring to their workflow.
The current lack of blockchain developers is both an advantage and a disadvantage. Anyone can contribute with innovation, but on the other hand, blockchain hasn’t yet undergone sufficient development to reach a level of global acceptance.
Using platforms like Ethereum, Bitcoin, or Corda for developing your own sidechain or contributing to the public one is not rocket science. Ethereum and Corda allow developers to create DApps, and Bitcoin provides the opportunity to execute and save transparent transactions. Multiple services like Github provide developers with code templates.
Blockchain’s future is ahead, and no one should be afraid to participate.