There are a few differences between the two:

  1. Bitcoin is a smart currency while Ethereum is for smart contracts.
  2. The algorithm used for bitcoin is SHA-256 whereas for Ethereum, its ether.
  3. While blockchain has a block time of 10 minutes, Ethereum has a block time of a mere 12-14 seconds.
  4. While blockchain has not yet been deemed scalable, the prospects to scale Ethereum are huge.

The biggest advantage of blockchain which has made it so popular is its ability to enable information to be distributed without letting the users copy it.

No, there are three types of blockchain; Public, Consortium, and Private.

There are two types of records in any given blockchain database. They are:

  1. Transactional Records
  2. Block Records

While both are easily accessible, you may also integrate one of them with the other.

The four main key features of blockchain are:

  1. Decentralized Systems
  2. Safer & Secure Ecosystem
  3. Distributed Ledger
  4. Minting

Encryption is a process that helps the owner to keep his data safe. As data security always has been a challenge, organisations heavily rely on encryption for data security.

Encryption as a process has a unique methodology. It changes the data and encodes it when it is sent out on a network. This ensures that only authorised people can access its information.

Yes, Blockchain heavily relies on it as a process and an approach to secure data. Blocks become secure and remain authentic though this approach.

Records that form the core of data in a Blockchain are stored in blocks. These blocks, when linked to other blocks, create a chain which is called Blockchain. So, the blocks are the basic elements that come into existence by amalgamation of data.

Yes, there is a difference between Wei and Ether based on their value. We can say that many Wei comes and add themselves up to create an Ether. To make it simpler, Wei is like currency, and 1 Ether or 1 ETH = 1⁰¹⁸ Wei

At some point, the blockchain interview questions are going to get a bit complex. For a fresher, a lot of questions asked would be theoretical. This helps to understand the clarity of concepts of a candidate.

One general advice while taking a blockchain interview is that you need to be sorted and confident about what you say. It is okay to pass on a question or to mention that you are only guessing if you are unsure about any particular one. It really gives you a chance to relax and be authentic.

Coming back to the question, answering this one is pretty simple. Security Policy defines the things that need to be secured on a system. It binds a user within some protocols that it must agree to and follow. This enhances overall security. Usually, it is observed with crucial information, a layer of security policies is implemented.

There are a few of them. The most important of them are:

  1. RSA
  2. Triple DES
  3. Blowfish
  4. Twofish
  5. AES

Yes, RSA is a very secure algorithm. But there are different ways that this algorithm is attacked. It may be attacked by brute force, and occasionally attacked mathematically.

Security is the most important part of a digital transaction and developers have used the approach of Secret Sharing for this very purpose. This approach helps in diving the secret and personal into units that are different and then sends these to users on the network.

Off Chain Transactions are the movements of value that are placed outside the blockchain. While a simple transaction or an on-chain transaction modifies blockchains apart from depending on the blockchain to determine the validity. The off-chain transactions rely on other methods to validate transactions and even record them.

Seemingly a very practical question, you may delve into some theory while answering this one. Threats to information are increasing on a daily basis. Increased transactions mean, increased attempts to hack the systems, especially ones that contain financial information. Listing out the threats you should talk about the threats that you face, or some general ones like identity theft, sabotage, software attack or information extortion.

Yes, it occurs when a group of people hold greater than 50% Network Hash Rate. In this instance, these people can easily manipulate transactions. Although, this is in truth likely to be a hypothetical situation but is a common part of blockchain developer interview questions.

There are three main elements:

  1. Timestamp
  2. Hash pointer
  3. List of transactions

It is seemingly a very obvious question, but many miss its answer. Blocks are always linked in a backward order. Each block gets linked to its previous block.

Not only can an information bring a company into crisis due to reputation harm, but it can also bring about financial losses to an organisation too. Lost trust of customers affected may result in a depletion of repeat business.

Yes, every block has a pointer that acts as a link to find it.

No. Once you have saved the information, to modify it, you would have to erase all information that rests on other associated blocks.

Blocks can be identified by their height and block.