Blockchain Platforms Coursera Quiz Answers – Networking Funda

Blockchain Platforms Week 1 Quiz Answers

Quiz 1: Self-Check

Q1. What are Hyperledger frameworks used for?

• Hyperledger frameworks are primarily used for building permissioned blockchains for organizations.
• Hyperledger frameworks are used for only building smart contracts for IBM’s blockchain.
• Hyperledger frameworks are primarily used for building smart contracts for public blockchains.
• Hyperledger frameworks are primarily used for building public blockchains.

Q2. The cryptocurrency for Hyperledger is called Hyperledger Iroha?

• True
• False

Q3. Smart contracts in hyperledger are called?

• Coded contracts
• Chaincode
• Smartcode
• Smart contract

Q4. At the time of this video recording, which of the following is out of incubation and into production?

• Sawtooth
• Iroha
• Burrow
• Fabric

Quiz 2: Self-Check

Q1. A popular way to explain an emerging technology is through?

• Research Paper
• Whitepaper
• Press conference
• Blog post

Q2. The hyperledger fabric framework only offers blockchain services

• True
• False

Quiz 3: Self-Check

Q1. Ledger in the Hyperledger Fabric is a record of state transitions, true or false?

• False
• True

Q2. Assets on Hyperledger Fabric represent tangible items of value that are transacted on the blockchain, true or false?

• True
• False

Q3. Within a channel, there is no available method to keep the data confidential from participating entities. True or False?

• True
• False

Q4. What does MSP stand for in the context of Hyperledger Fabric?

• Member Selection Protocol
• Metadata Storage Peer
• Membership Service Provider
• Member Security Protocol

Q5. Hyperledger Fabric only allows Proof of Work consensus to be plugged in to ensure a high degree of trustworthiness.

• True
• False

Quiz 4: Self-Check

Q1. What is the main tool used for building business applications in Hyperledger Fabric?

• Quilt
• Composer
• Cello
• Sawtooth

Q2. What was the earlier name of the Composer tool?

• Confetti
• Concerto
• Cornetto
• Consento

Quiz 5: Self-Check

Q1. What is the main contribution of Microsoft Azure to the blockchain ecosystem?

• Blockchain as a service
• Private blockchain powered by Cortana
• Public blockchain powered by Cortana

Q2. What is the top level aim of Microsoft Azure?

• Integrate Microsoft services into public blockchains
• Accelerate blockchain deployment.
• Provide cloud support to host Dapps
• Provide oracle services to public blockchains

Quiz 6: Permissioned Blockchains – Week 1

Q1. What is the main goal of the Hyperledger project?

• Help accelerate development on IBM’s blockchain
• Common functional modules and reuse of command building blocks.
• Provide blockchain as a service

Q2. What are some implementations of Hyperledger frameworks?

• Explorer
• Fabric, Sawtooth
• Composer

Q3. What are some of the Hyperledger tools?

• Editor, Compiler
• Fabric, Sawtooth
• Composer, Explorer

Q4. A significant difference between bitcoin and Hyperledger is that ____.

• unknown peers can join but, but need to be authorized to deploy smart contracts
• anyone can join, but miners do not receive money
• unknown peers cannot join and leave the network as they wish

Q5. What are the main services offered by Hyperledger Fabric?

• Assets
• Identity, Policy, Blockchain, Smart Contract
• Channels
• Composer

Q6. Hyperledger Fabric allows for pluggable consensus algorithms. True or False?

• True
• False

Q7. These are some of the components of the Fabric model.

Peers

• Assets
• Identity
• Channels
• All of the above.

Q8. Hyperledger functions include

• Identity, Consensus, Membership
• Peers, Assets and Channels
• Identity, Consensus and Channels
• Identity, Consensus and Assets

Q9. There are three types of peers:

• Active, Ordering, Committing
• Endorsing, Ordering, Committing
• Passive, Endorsing, Neutral
• Passive, Active, Neutral

Q10. What is the deployable file type .bna represent in Hyperledger Fabric?

• Binary Node Archive
• Business Network Archive
• Business Node Archive
• Binary Network Archive

Q11. Mention the services provided by Microsoft Azure in the context of blockchain.

• Network and security services.
• Rapid deployment of blockchain infrastructure and provide integration capability.
• Develop and test smart contracts.
• Provide basic business logic and conditions.

Q12. Which of the following blockchain is NOT supported by Microsoft Azure?

• Ethereum
• HyperLedger Fabric
• Bitcoin
• R3 Corda

Blockchain Platforms Week 2 Quiz Answers

Quiz 1: Self-Check

Q1. The token used in Augur in the context of reporting is called ___

• Coin
• Gas
• Eth
• REP

Q2. Augur’s REP Token is ERC 20 compliant. True or false?

• True
• False

Q3. What is the blockchain technology on which Augur is based?

• Bitcoin
• Dash
• Hyperledger
• Ethereum

Q4. Wisdom of the crowd is captured by a service called ____.

• Oracle
• Event
• Browse
• Mine

Q5. Augur is a public blockchain based decentralized app. True or False?

• False
• True

Q6. The Augur organization serves as the central authority and handles payback to and collection from participants.

• True
• False

Quiz 2: Self-Check

Q1. What are the four phases of the energy supply chain?

• Mining, Transmission, Distribution, Sales
• Production, Storage, Distribution, Retail
• Production, Transmission, Distribution, Retail

Q2. What are the two types of energy markets?

• Regulated, Deregulated
• Black, White
• Private, Public

Q3. BOLT, the Grid+ token, is ERC20 compliant. True or False?

• True
• False

Q4. Which blockchain technology does Grid+ use?

• Dash
• Bitcoin
• Ethereum
• Hyperledger

Q5. Payments in Grid+ are done using Ether.

• True
• False

Quiz 3: Decentralized Applications Platforms – Week 2

Q1. What is Augur?

• A private blockchain
• A fintech market prediction algorithm
• A decentralized market prediction platform based on Ethereum
• A public blockchain

Q2. What are some of the key ideas behind Augur?

• Ethereum Mining, End-to-End Market place prediction, Robust Algorithms
• Knowledge transfer, Trading platform, reputation system
• Membership services, Consortium Blockchain
• Trading platform, reputation system, crowd reporting process

Q3. What are the 3 main roles in the Augur prediction process?

• Marketplace creator, trader, reporter
• Marketplace creator, participant, learner
• Marketplace initiator, proposer, learner
• Marketplace initiator, proposer, reporter

Q4. Augur has robust methods to address forks in its dispute phase. True or False?

• True
• False

Q5. Augur is an automated system that leverages these blockchain features.

• Smart contracts, Immutable ledgers, oracle
• Mining
• Trading, Proof of Work
• Cryptographic hashing

Q6. What major phase does Grid+ replace in the energy supply chain

• Transmission
• Retail
• Distribution
• Production

Q7. What are two main components of the Grid+ system?

• Energy retailer & Smart agents
• Energy Production & Energy Transmission
• Energy donation & Energy mining

Q8. What are special features of the Grid+ system?

• Efficient sourcing and distribution of energy
• Energy efficient mining, sales
• Intelligent electricity usage, Integration with IOT devices

Q9. How is security enforced in the Grid+ system?

• Certificate authority
• Single cryptographic signature
• Multiple signatures are used to control the smart agent operation

Q10. In Grid+ system, efficiency is achieved by?

• Efficient distribution of energy using smart contracts
• Direct payment to retailer, payment and energy used automation
• Efficient use of energy for mining on the blockchain

Q11. The trading currency in Augur (at the time of the video) is:

• Ripple
• Ether
• Bitcoin
• Dollar

Blockchain Platforms Week 3 Quiz Answers

Quiz 1: Self-Check

Q1. What is the common consensus protocol used in Bitcoin and Ethereum Metropolis?

• Proof of authority
• Proof of weight
• Proof of work
• Proof of stake

Q2. What is a major problem with Proof Of Work?

• It is CPU-intensive and consumes enormous amount of power.
• It is unreliable
• Multiple miners have to be rewarded
• It is difficult to implement

Q3. Which of the following is used in solving a POW puzzle?

• Fragmenting
• Hashing
• Encrypting
• Sharding

Q4. In Practical Byzantine Fault Tolerance, ___.

• the nodes elect a leader and that leader adds the next block
• the node with most coins is chosen for adding the next block
• a master node selects the next node that adds the next block

Quiz 2: Self-Check

Q1. What is the size of the bitcoin block since 2010 ?

• 1 KB
• 2 MB
• 1 MB
• 1 GB

Q2. Transaction rate on bitcoin blockchain is a main concern for many practical applications?

• False
• True

Q3. List two solutions for improving scalability ?

• Smaller block size and on-chain transactions
• Smaller block size and off-chain transactions
• Larger block size and on-chain transactions
• Larger block size and off-chain transactions

Q4. Every Ethereum block holds a fixed number of transactions. True or False?

• True
• False

Quiz 3: Self-Check

Q1. What is a simple way of achieving privacy?

• Using a permissioned blockchain
• Using end-to-end encryption
• Using role management

Quiz 4: Self-Check

Q1. Smart contract accounts in Ethereum can hold a balance. True or False?

• False
• True

Q2. What is an escrow?

• Escrow is payment for smart contracts
• Escrow is cost of execution of smart contracts
• Escrow is an agreement in which assets are held and distributed when conditions are met
• Escrow is a permissioned blockchain

Q3. What is the common Multi-sig feature of Bitcoin?

• Pay-to-miner hash (P2MH)
• MD5 hash
• Pay-to-owner hash (P2OH)
• Pay to Script hash (P2SH)

Q4. What is Multi-sig in the context of smart contract?

• All the nodes on the blockchain have to sign the transaction
• A transaction has to be authorized by multiple signatures
• A transaction has to be authorized by the owner of smart contracts

Quiz 5: Challenges & Solutions – Week 3

Q1. Why is consensus in a blockchain important?

• It prevents double spending of cryptocurrencies.
• It increases speed of transactions.
• It ensures integrity of the records on the chain.
• It prevents double mining of the same block.

Q2. Mention two alternatives to POW?

• POT (Proof Of Trust)
• POS (Proof Of Stake)
• PBFT (Practical Byzantine Fault Tolerance)
• POC (Proof Of Correctness)

Q3. Main concept behind Practical Byzantine Fault Tolerance is ____.

• Efficient forking of the blockchain
• Choosing winning miner
• Election of a leader

Q4. The main concept of Proof Of Stake is ____.

• Full nodes with most coins at stake get to create the next block
• Full nodes with the least coins get to delete a block
• Full nodes with most coins at stake get to delete a block
• Full nodes with least coins at stake get to create the next block

Q5. What was the main concept behind SegWit2x improvement?

• Decrease the total number of transactions that take place
• Accommodate more transactions in the same size block
• Cut the block size to half to improve speed
• Double the block size to accommodate more transactions per block

Q6. What is lightning network?

• An on-chain payment channel for Bitcoin.
• An on-chain payment channel for Ethereum.
• An off-chain payment channel for Bitcoin.
• An off-chain payment channel for Ethereum.

Q7. How do state channels solve the scalability issue?

• Transactions operate at a much higher speed since they synchronize continuously with the main chain.
• Transactions operate independently of the main chain with no synchronization.
• Transactions operate at a much higher speed and synchronize periodically with the main chain.

Q8. What is Raiden network?

• A side chain for Bitcoin based main chain.
• A side chain for Litecoin based main chain.
• A side chain for Hyperledger.
• A side chain for Ethereum based main chain.

Q9. What is a simple way of improving confidentiality?

• Encrypt the data transacted and digitally sign it.
• Assign security codes to each node.
• Add role management to the smart contract.

Q10. How do smart contracts implement escrow?

• Using combination of account balance and modifiers for enforcing conditions.
• Using special access accounts to hold ethers.
• By notifying the owner to release the assets when the required balance is received.

Q11. Multi-sig address in Bitcoin begins with a character 3. True or False?

• True
• False

Q12. Proof of Stake consensus algorithm has extremely high power requirements.

• True
• False

Blockchain Platforms Week 4 Quiz Answers

Quiz 1: Self-Check

Q1. Who created IPFS?

• Juan Benet
• Satoshi Nakamoto
• Joseph Carl Robnett Licklider
• Bram Cohen

Q2. The IPFS hash depends upon the ____.

• File name
• Node and file name
• Content of the file

Q3. What command is used to spin up IPFS in your system?

• 1
• ipfs run
• 1
• ipfs init
• 1
• ipfs start
• 1
• ipfs daemon

Q4. IPFS is a ____.

• Blockchain implementation
• Centralized File System
• Content-addressed system

Q5. IPFS supports version controlling just like git. True or False?

• False
• True

Q6. How is the location of the file resolved?

• Distributed Hash Table
• Merkle DAG
• Centralized Hash Table
• Location Resolving Protocol

Q7. Peer nodes are incentivized using ____.

• BitSwap Protocol
• Self-Certification Servers
• Bit Torrent File Distribution Protocol
• Merkle DAG

Quiz 2: Self-Check

Q1. Who invented Hashgraph?

• Juan Benet
• Bram Cohen
• Leemon Baird
• Satoshi Nakamoto

Q2. What are the goals of Hashgraph?

• Order the transactions with low latency and minimal power consumption.
• Order the transactions with high latency.
• Order the transactions with low eventual consistency.
• Better ordering of transactions than blockchain protocol but with high energy consumption.

Q3. How are Hashgraph edges generated?

• Edges are generated by connecting nodes based on their hash.
• Edges are generated randomly
• Edges are generated by gossiping of events between nodes

Q4. What are the attributes in an event in Hashgraph?

• Event ID, Timestamp and hash of the parents
• Event ID, Timestamp and hash of all the nodes
• Event ID, Timestamp and hash of current node

Q5. How is consensus in Hashgraph achieved?

• Gossiping information about new transactions
• Practical Byzantine Fault Tolerance
• Proof Of Stake
• Proof Of Work

Quiz 3: Self-Check

Q1. What is the butterfly effect of the Bitcoin blockchain?

• An ecosystem of innovative inclusive applications
• A cryptocurrency system that will replace fiat currency
• An permissioned peer-to-peer currency system

Q2. According to industry experts when did the major businesses realize that blockchain is not just about cryptocurrency?

• 2015
• 2008
• 2013
• 2017

Quiz 4 : Alternative Decentralized Solutions

Q1. What is the IPFS hash of myfile1.txt when you added the file to IPFS? Please copy the hash as an answer below. Make sure you do not include any leading or trailing spaces.

Note: If you are taking this quiz after a previous attempt and have changed the content of myfile1.txt, we recommend you download the file again and use it instead of reverting the changes in the old one.

If this is your first attempt, please ignore this note.

Note: If you are taking this quiz after a previous attempt and have changed the content of myfile1.txt, we recommend you download the file again and use it instead of reverting the changes in the old one.

Q2. What is the size, in characters, of an IPFS file hash using Base58 encoding method?

• 20
• 32
• 64
• 44

Q3. What are 58 alphanumeric characters making up the Base58?

• Capital letters, lowercase letters, Numerals 0 and 1 and _, -, &, %
• Capital letters without (O, I), Lowercase letters without (l), Numerals without (0)
• Capital letters without (Q), Lowercase letters without (m) and numbers 1-8
• Capital Letters from A-X, Lowercase letters from a-x, Numerals 0-9

Q4. What is the command to add a file logo.txt to the IPFS using command line interface?

• ipfs cat logo.txt
• ipfs add logo.txt
• ipfs send logo.txt
• ipfs pin logo.txt

Q5. What is the command for viewing a text file myfile1.txt using the command line interface?

• ipfs check myfile1.txt
• ipfs cat myfile1.txt
• ipfs get myfile1.txt
• ipfs view myfile1.txt

Q6. How do you access the web interface to the IPFS in the exercise that you completed?

• Through a browser using https://gateway.ipfs.io/ipfs/
• Through the command line by typing ipfs webui
• By downloading the additional webui pack from the ipfs website
• Through a browser using localhost://5001/webui

Q7. What is DAG with reference to IPFS?

• Directed Acylic Graph of all the files/objects in the IPFS
• Directory of Addressed Graph
• Daemon Address Generation

Q8. What information does the Connection tab of the IPFS provide?

• Have-Want table of BitSwap
• Network statistics about the user’s internet connection
• The details of the peers currently connected to the IPFS

Q9. What is the IPFS hash of the folder that you added to IPFS? Please copy the hash as answer below. Make sure you do not include any leading or trailing spaces.

Note: If you are taking this quiz after a previous attempt and have changed the content of myfile1.txt, we recommend you download the file again and use it instead of reverting the changes in the old one.

If this is your first attempt, please ignore this note.

Q10. Edit the content of myfile1.txt. Add a single “A” as the first character to the file. Now what happens to the hash of the myfile1.txt?

• Distributed Hash Table recognizes it as a single change to the file and keeps the old hash
• Whole hash changes to a different hash value
• One character in the hash value changes
• File corrupted warning shows up

Q11. When the myfile1.txt was changed as above, what happens to the hash address of the folder?

• Distributed Hash Table recognizes it as a single change to the file and keeps the old hash
• File corrupted warning shows up
• One character in the hash changes
• Whole hash changes to a different hash value

Q12. IPFS is IP-addressed. True or False?

• True
• False

Q13. The files on the IPFS are stored on all the nodes on an immutable ledger. True or False?

• True
• False

Q14. How are files on IPFS addressed?

• Universally unique hash
• Location of the file on some server
• Location on the immutable ledger
• Location of the file on some node in the IPFS

Q15. If two different nodes add the same file, then ___.

• The hashes will be the same
• Their hashes will be same provided the filenames are the same
• Their hashes will be different.

Q16. IPFS is strictly blockchain-based. True or False?

• True
• False

Q17. IPFS currently only offers support for text and image files. True or False?

• True
• False

Q18 .What is the command for downloading a text file myfile1.txt using the command line interface?

• ipfs store <hash of myfile1.txt>
• ipfs get <hash of myfile1.txt>
• ipfs fetch <hash of myfile1.txt>
• ipfs dld <hash of myfile1.txt>

Q19. Base58 encoding scheme has fewer distinct symbols than Base64 encoding scheme to ____.

• Reduce the complexity by removing 8 characters
• Remove bugs arising due to common string operation characters like +
• Make it easier for humans by eliminating ambiguous characters
• Remove possibility of breaks in code because of characters like “ and ;

Q20. How do you view the hash of a file that is already on the IPFS using the CLI?

• Using ipfs get
• Using ipfs view
• Using ipfs files ls -l
• Using ipfs hash ls -l

All Course Quiz Answers of Blockchain Specialization

Course 01: Blockchain Basics

Course 02: Smart Contracts

Course 03: Decentralized Applications (Dapps)

Course 04: Blockchain Platforms