Blockchain Interview Questions Programming

Blockchains are of basically three types and they are:

Public , Private & Consortium

Whatsoever the platform or software the data security is always important and really matters and thus Encryption is basically an approach that helps organizations to keep their data secure all the time.

The encrypted data is encoded & changed up to some extent before it is sent out to a network by the sender and only authorized parties/users can access that information.

In the Blockchain, this approach is very useful because it simply adds more to the overall security and authenticity of blocks and helps to keep them tightly secure.

Blockchain can be trusted due to various reasons and they’re.

• It’s secure as it is meant for online transactions, the developers of Blockchains had focussed special attention to keeping up the pace when it comes to its security.
• It really doesn’t really matter what type of business one owns, Blockchain will  easily be considered for all use case and business models.
• Its compatibility with other business applications due to its open-source nature.

There are four major features of blockchain:

• Decentralized Systems
• Distributed ledger
• Safer & Secure Ecosystem
• Minting

Blockchain consists of a list of records and those records are stored in blocks. These blocks are in turn linked with other blocks and hence constitute a chain is called Blockchain.

A Block or the entire blockchain is protected by a strong cryptographic hash algorithm. Each block has a unique hash pointer, any modification in the block constituents will result in the change in the hash identifier of the block.  Thus, it offers an high level of security. Hence, we no need to worry about the safety as well as the security of data that is present in a block.

Blockchain is considered as an incorruptible.

To take over the network, an attacker would have to control more than fifty percent of its total computing power.

There are 3 common type of Ledgers that can be considered by users and they’re :

There are no restriction on keeping records of any type in the Blockchain approach. Most of the organizations are using Blockchain for securing all types of records.

The common types of records that can be placed on the Blockchains are:

• Transaction processing
• Business transactions,
• Records of medical transactions
• Identity management
• Management activities  and
• Documentation

The system relies on the Network servicing protocol and the nodes that belongs to network.

Below pictorial representation will explain the components of blockchain Ecosystem:

 Below are the few differences between  Proof-of-work vs proof-of-stake

Below are the major benefits of Blockchain.

Blockchain records mainly categorized as

Block records and 

Transactional records. 

Both of these records can easily be accessed and the good thing is, it is possible to integrate them each other without following the complex algorithms.

Mining is used as a proof of work for participants in the blockchain.

Whenever a block of transactions is to be agreed, every participating node attempts to ‘mine’ the block (a mathematical algorithmic process that requires extensive CPU capacity).

In public blockchains successful mining is rewarded with a cryptocurrency token.

Mining is used as a proof of work for participants in the blockchain.

Whenever a block of transactions is to be agreed, every participating node attempts to ‘mine’ the block (a mathematical algorithmic process that requires extensive CPU capacity).

In public blockchains successful mining is rewarded with a cryptocurrency token.

Blockchain is the core technology behind the bitcoin.

At its heart is a distributed data store. Anyone who participates in this network has their own data store that stores all of the transactions that ever happened on the network (this is also known as the distributed ledger).

Entries are stored within a cryptographic chain of blocks. At every stage, the network of participants must agree about the latest block of transactions.

Agreement is reached through a process of majority consensus, eliminating duplicate entries, double spending etc.

This process and the cryptographic layering of the blocks makes the agreed blockchain irreversible and immutable.

The ‘history’ of events within this technology cannot be modified by any one of the participants without majority consensus from the group.

Private blockchains are deployed either within an organization or shared among a known group of participants.

They can be limited to a predefined set of participants. In this case, no one else can access them or the data residing in them.

They can be secured in a similar way to securing other integrated enterprise applications (e.g. firewalls, VPN etc).

A Smart Contract is code that is deployed to the blockchain. Each smart contract contains code that can have a predefined set of inputs. Smart contracts can also store data.

Following the distributed model of the blockchain, smart contracts run on every node in this technology, and each contract’s data is stored in every node. This data can be queried at any time.

Smart Contracts can also call other smart contracts, enforce permissions, run workflow logic, perform calculations etc.

Smart contract code is executed within a transaction – so the data stored as a result of running the smart contract (i.e. the state) is part of the blockchain’s immutable ledger.

Ethereum is a group of incredibly smart individuals who have developed the next generation of cryptocurrency.

The Ethereum project involves a large single network (much like Bitcoin), and runs on a cryptocurrency that can be mined (Ether).

We are looking at deploying private networks of the Ethereum (or similar) within organisations, or across small predetermined groups of organisations.

It means Bitcoin improvement proposal.

The Common Type Of Ledgers That Can Be Considered By Users In Blockchain are:

• Centralized Ledgers
• Decentralized Ledgers
• Distributed Ledgers