#blockchain

15 questions

Explain the different Application of Blockchain. Blockchain is used wherever many parties need a shared, tamper-proof record without a single trusted middleman: in finance, supply chains, h... 1 answer
What is UTXO? Explain how it prevents double spending A UTXO (Unspent Transaction Output) is an output of a previous transaction that has not yet been spent; in Bitcoin a user's balance is the s... 1 answer
What is the diffidence between pre-prepare, prepare phase, and commit phase in PBFT. In PBFT, the pre-prepare phase lets the primary assign a sequence number to a request, the prepare phase makes the replicas agree on that or... 1 answer
Write a solidity program for multilevel inheritance. In multilevel inheritance a contract inherits from a contract that itself inherits from another (A → B → C); in Solidity this is written wit... 1 answer
What is double spending problem? How pow solve the problem of double spending. Double spending is the risk that the same digital coin is spent twice, because digital data can be copied; Proof of Work prevents it by maki... 1 answer
Summarize the Solutions to achieve Byzantine Fault Tolerance. Byzantine fault tolerance (BFT) means a distributed system keeps reaching correct agreement even when some nodes are faulty or malicious; so... 1 answer
Explain Hyperledger fabric V1 architecture. Hyperledger Fabric v1 is a permissioned blockchain platform with a modular architecture made of a Membership Service Provider, peers (endors... 1 answer
Comparison between hyperleger fabric and other technologies. Technology Hyperledger Fabric Ethereum Corda Quorum Polkadot Tendermint Type Permissioned Public Permissioned Permissioned Interoperability... 1 answer
Explain PAXOS consensus Algorithm for Private Blockchain. Key Points: Introduced by Leslie Lamport in 1989. Solves the consensus problem in asynchronous distributed systems. Ensures all nodes agree... 1 answer
Compare different types of blockchain . Type Description Consensus Mechanism Scalability Security Centralization Examples Public Blockchain Open to anyone Proof of Work (PoW) or Pr... 2 answers
What are the main components of a Solidity Smart Contract? A Solidity smart contract is mainly made of a pragma (version) line, the contract declaration, state variables, a constructor, functions, fu... 1 answer
Explain Byzantine Generals Problem? Show the working of pBFT? The Byzantine Generals Problem asks how loyal parties can reach agreement when some participants may be traitors sending conflicting message... 1 answer
Describe the types of Consensus protocol in Blockchain. Consensus protocols let the nodes of a blockchain agree on a single valid order of blocks without trusting each other; the main types are Pr... 1 answer
Explain why Merkle Trees are Important For Blockchain Merkle trees let a blockchain summarise all transactions of a block in one 32-byte hash (the Merkle root) stored in the block header, so tha... 1 answer
Describe Blockchain Technology. How does Blockchain Work A blockchain is a distributed, decentralised, append-only ledger in which transactions are grouped into blocks, each block is linked to the... 1 answer