CSE598 BLOCKCHAIN FINAL
QUESTIONS & ANSWERS 100%
CORRECT!!
Where are the transactions recorded in a blockchain?
* On a SQL database
* On a distributed immutable ledger
* On a distributed opaque immutable ledger
* On a centralized immutable ledger - ANSWEROn a distributed immutable ledger
If the following are the six steps in the process of creating a new block, what is the
right time sequence in which the process happens?
1. Nodes verify transactions
2. Transactions were submitted to the network
3. Consensus algorithm
4. Select the header of the most recent block and insert it into the new block as hash
5. Bundle the transactions into a block
6. New block is added to the local blockchain and propagated to the network -
ANSWER2,1,5,4,3,6
2. Transactions were submitted to the network
1. Nodes verify transactions
5. Bundle the transactions into a block
4. Select the header of the most recent block and insert it into the new block as hash
3. Consensus algorithm
6. New block is added to the local blockchain and propagated to the network
Which of the following is used to point to a block in the blockchain:
* Hash pointer
* User ID
* Transaction ID
* Timestamp - ANSWERHash pointer
TF: A block in the blockchain can have more than one parent block. - ANSWERFalse
In Ethereum it is stated that the ledge of a cryptocurrency such as Bitcoin can be
thought of as what?
* A smart contract
* A state machine replication
* A state transition system
* A decentralized autonomous organization - ANSWERState transition system
A blockchain configuration that allows participating members to come from within its
organization defines - ANSWERprivate or permissioned
, Which of these are NOT contained in a block of a blockchain?
* The hash value of the last block in the chain
* The has value of the block
* The has value of the previous block in the chain
* Data that is stored in the block - ANSWERThe has value of the last block in the
chain
Any electronic device that maintains a copy of the blockchain and keeps the network
functioning is called a
* Server
* Node
* Token
* Reward - ANSWERNode
Blockchain is "immutable". What does it imply?
* The cannot be altered
* They can only store numerical data
* Any user cannot access them
* Their computation speed is not limited - ANSWERThey cannot be altered
If a hacker wanted to alter a blockchain, what percentage of the block copies would
he have to alter? - ANSWER51%
Suppose you have eight data points - 1 to 8. The post-order traversal of the Merkle
Tree is given by (here 8 means hash of 8, 43 means to combined hash of 4 and 3,
and so on)
* {8, 7, 87, 6, 5, 65, 8764, 4, 3, 43, 2, 1, 21, 4321, 87654321}
* {8, 87, 7, 8764, 6, 65, 5, 87654321, 4, 43, 3, 4321, 2, 21, 1}
* {1, 2, 12, 3, 4, 34, 1234, 5, 6, 56, 7, 8, 78, 5678, 12345678}
* {87654321, 8765, 87, 8, 7, 65, 6, 5, 4321, 43, 4, 3, 21, 2, 1} - ANSWER{1, 2, 12, 3,
4, 34, 1234, 5, 6, 56, 7, 8, 78, 5678, 12345678}
What is one of the requirements of secure hashing function?
* It is an ECC function
* It is a one-way function
* It is a log function
* It is a secret function - ANSWERIt is a one-way function
Given an input m1 it should be difficult to find another input m2 such that m1 != m2
and hash(m1)=hash(m2). This property is called?
* Second preimage resistance
* Collision resistance
* Replay attack resistance - ANSWERSecond Preimage Resistance
What will be the height of the hash tree with branching factor 2 and with 8 records? -
ANSWER4
The Merkle Trees are constructed in a?
* Bottom-up approach
QUESTIONS & ANSWERS 100%
CORRECT!!
Where are the transactions recorded in a blockchain?
* On a SQL database
* On a distributed immutable ledger
* On a distributed opaque immutable ledger
* On a centralized immutable ledger - ANSWEROn a distributed immutable ledger
If the following are the six steps in the process of creating a new block, what is the
right time sequence in which the process happens?
1. Nodes verify transactions
2. Transactions were submitted to the network
3. Consensus algorithm
4. Select the header of the most recent block and insert it into the new block as hash
5. Bundle the transactions into a block
6. New block is added to the local blockchain and propagated to the network -
ANSWER2,1,5,4,3,6
2. Transactions were submitted to the network
1. Nodes verify transactions
5. Bundle the transactions into a block
4. Select the header of the most recent block and insert it into the new block as hash
3. Consensus algorithm
6. New block is added to the local blockchain and propagated to the network
Which of the following is used to point to a block in the blockchain:
* Hash pointer
* User ID
* Transaction ID
* Timestamp - ANSWERHash pointer
TF: A block in the blockchain can have more than one parent block. - ANSWERFalse
In Ethereum it is stated that the ledge of a cryptocurrency such as Bitcoin can be
thought of as what?
* A smart contract
* A state machine replication
* A state transition system
* A decentralized autonomous organization - ANSWERState transition system
A blockchain configuration that allows participating members to come from within its
organization defines - ANSWERprivate or permissioned
, Which of these are NOT contained in a block of a blockchain?
* The hash value of the last block in the chain
* The has value of the block
* The has value of the previous block in the chain
* Data that is stored in the block - ANSWERThe has value of the last block in the
chain
Any electronic device that maintains a copy of the blockchain and keeps the network
functioning is called a
* Server
* Node
* Token
* Reward - ANSWERNode
Blockchain is "immutable". What does it imply?
* The cannot be altered
* They can only store numerical data
* Any user cannot access them
* Their computation speed is not limited - ANSWERThey cannot be altered
If a hacker wanted to alter a blockchain, what percentage of the block copies would
he have to alter? - ANSWER51%
Suppose you have eight data points - 1 to 8. The post-order traversal of the Merkle
Tree is given by (here 8 means hash of 8, 43 means to combined hash of 4 and 3,
and so on)
* {8, 7, 87, 6, 5, 65, 8764, 4, 3, 43, 2, 1, 21, 4321, 87654321}
* {8, 87, 7, 8764, 6, 65, 5, 87654321, 4, 43, 3, 4321, 2, 21, 1}
* {1, 2, 12, 3, 4, 34, 1234, 5, 6, 56, 7, 8, 78, 5678, 12345678}
* {87654321, 8765, 87, 8, 7, 65, 6, 5, 4321, 43, 4, 3, 21, 2, 1} - ANSWER{1, 2, 12, 3,
4, 34, 1234, 5, 6, 56, 7, 8, 78, 5678, 12345678}
What is one of the requirements of secure hashing function?
* It is an ECC function
* It is a one-way function
* It is a log function
* It is a secret function - ANSWERIt is a one-way function
Given an input m1 it should be difficult to find another input m2 such that m1 != m2
and hash(m1)=hash(m2). This property is called?
* Second preimage resistance
* Collision resistance
* Replay attack resistance - ANSWERSecond Preimage Resistance
What will be the height of the hash tree with branching factor 2 and with 8 records? -
ANSWER4
The Merkle Trees are constructed in a?
* Bottom-up approach
