15 Commonly Asked Blockchain Interview Questions & Answers

Indeed, In this era which is a technology-driven world, blockchain has emerged as a game changer. It has converted how we behave, and store information as companies apply blockchain to their operations. There is a high demand for skilled blockchain professionals. If you are an experienced developer or a fresher, mastering blockchain interview questions requires a deep understanding of basic concepts and practical applications. Here we will explore 15 commonly asked blockchain interview questions and answers. This will help you in your next interview.

15 Blockchain Interview Questions and Answers

Ques 1. What is Blockchain technology?

Ans- This is one of the very basic and important blockchain interview questions. The answer to this blockchain question is Blockchain is a decentralized ledger technology. This stores data in the form of blocks that are linked with each other forming a chain. Here each block in the chain has a cryptographic hash of the previous block resulting in temper-resistant chains of block.

Ques 2. Name the different types of Bitcoin.

Ans- You can answer these types of blockchain interview questions by saying that blockchain is mainly for four types.

• Public — This is open to everyone; anyone can read, write, and validate transactions without permission, such as Bitcoin and Ethereum. Here all transactions are publicly visible.
• Private- This type of blockchain needs permission to access, and participation is restricted to only authorized people. Private blockchains are used mainly in organizations for confidential transactions and internal operations. For example, Hyperledger Fabric and Corda.
• Consortium- This category of the blockchain is similar to the private blockchain. The difference is here a group of trusted authorities can get access. Consortium blockchains are used during collaboration or shared projects or industries. Here participants maintain control over the network while sharing responsibilities for consensus and validation. Examples are the R3 Corda Network and Hyperledger Consortium.
• Hybrid- This type of blockchain is a combination of public and private blockchains. This gives a customizable and flexible solution for many use cases. In this type of blockchain, some parts of the network are public whereas other parts are private. An example is Dragonchain.

Ques 3. How does security is ensured in Blockchain technology?

Ans- Cryptographic techniques like hashing and digital signatures ensure security in the Blockchain. In blockchain technology, every block includes a hash of the previous block. R Hence no one can easily play with the historical data. Furthermore, there are consensus mechanisms such as proof of work or proof of stake. This validates the transactions and stops fraudulent activities.

Ques 4. How does PoW is different from PoS?

Ans- Both of these are the consensus mechanisms of the blockchain networks.

Proof of Work- POW is a mechanism where participants solve complex mathematical puzzles and validate the transactions or create new blocks.

Proof of Stake — whereas in PoS, authorized validators having a stake in the network can validate transactions. It depends on the amount of cryptocurrency they have.

Ques 5. What is a Bitcoin?

Ans- This is also one of the most common Blockchain interview questions. Bitcoin is a cryptocurrency created in 2008. All transactions between Bitcoin are recorded on the Blockchain.

Ques 6. Explain Smart Contracts.

Ans- Smart contracts mean self-executing contracts. These are with some predefined rules and regulations in the form of written code. These contracts can be executed automatically and implement terms according to the predetermined conditions. They use the blockchain platform Ethereum.

Ques 7. What types of records can a blockchain have?

Ans- Five types of records can be kept on the blockchains which are

• Business transactions
• Identity management
• Management activities
• Transaction processing
• Medical transactions

Ques 8. Is blockchain technology helpful in supply chain management?

Ans- Yes. We can have transparency, traceability, and increased efficiency by using blockchain technology in supply chain management. Blockchain records every transaction on a ledger that is temper-resistant. This enhances the trust between the stakeholders.

Ques 9. What is the meaning of the Blockchain ecosystem?

Ans- The blockchain ecosystem is the interconnected network of individuals, companies, technologies, or protocols. The purpose is to develop, adopt, and operate blockchain technology collectively. This allows enterprises to share business processes and data.

Ques 10. What do you understand by the dApp? Explain its difference from the Smart contracts.

Ans- A dApp or decentralized application is a software application. It runs on a decentralized network of computers using blockchain technology. This offers transparency, autonomy, and censorship resistance.

On the other hand, Smart contracts are self-executing contracts where defined rules allow the automated transactions between two parties.

Ques 11. In blockchain technology what are the scalability challenges that can happen?

Ans- Scalability is one of the biggest issues for Blockchain. Mainly in the case of public networks like Ethereum and Bitcoin. It is difficult to maintain decentralization and security with the increasing number of transactions. This is difficult because of the limited block size, network congestion, and consensus algorithm inefficiencies

Ques 12. How blocks are added to a Blockchain?

Ans- This is one of the most common blockchain interview questions you can face during the interview. By the process of mining, blocks can be added to the blockchains.

This involves steps of validating more than half of transactions, creating a new block, and also appending this to the existing blockchain.

Ques 13. What exactly is Double Spending?

Ans- Double spending is a phenomenon where the same digital token or currency is spent more than once. This happens when a user initiates multiple transactions using the same funds.

Ques 14. Explain 51% attack.

Ans- A 51% attack, a major threat to the blockchain networks, is also known as a majority attack or majority hash power attack. This is especially true for the network that works on POW mechanisms such as Bitcoin. It works when a malicious group of actors gets control of more than 50% of the total computational power of the network.

Ques 15. How is blockchain different from a database?

Ans- We can differentiate Blockchain and Database in the following manner.

Blockchain

• Decentralized Network
• Provides immutability and tamper resistance
• Offers good transparency and audibility

Database

• Databases are centralized, where data is stored and managed by a single authority or server.
• Less secure, and data can be modified or deleted by authorized users.
• Limited transparency and audibility

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Conclusion

If you want to master the blockchain interview questions, you will need a strong understanding of the basics, practical applications, and emerging trends. Familiarize yourself with these commonly asked Blockchain questions and answers. You can enroll in the Blockchain Developer course by Henry Harvin to prepare yourself to face the blockchain interview questions. Clearing these blockchain questions will allow us to seize a good opportunity in this field.

FAQs

Q1- Is an online Blockchain developer course worth it?

Ans- Yes. Henry Harvin’s online Blockchain course is a two-way interactive comprehensive course. It offers you a flexible schedule and is delivered by industry experts. Prepare for Blockchain interview questions also as you pursue this course.

Q2- What jobs can I get after clearing Blockchain interview questions?

Ans- There are many jobs available for the blockchain developer in the market.

Such as

• Blockchain Developer
• Blockchain Engineer
• Smart Contract Developer
• Cryptocurrency Analyst, etc.

Q3- What salary can I expect after the Blockchain developer course?

Ans- Blockchain developers usually get a package between 5 to 30 LPA. It’s important to practice blockchain interview questions to get a good job.

Q4- How can I prepare for the Blockchain interview questions?

Ans- The best way to master the Blockchain questions is to have a strong grip on the basics and all concepts. This you can achieve by enrolling in a Blockchain course and doing a lot of practice.

Q5- Will I become a certified professional after the Blockchain course?

Ans- Yes. Henry Harvin offers a hallmark globally recognized certificate. This will enhance your professional credibility.