Table of Contents
B.Tech 8th Semester Exam, 2022 (Code: 100816)
Question (a): Encryption is
- (i) putting data into code making it difficult to read or understand
- (ii) jumbling data
- (iii) a formal language
- (iv) a secret way of writing programs
- Correct Answer: (i) putting data into code making it difficult to read or understand
Question (b): ___ is not a property of hash function.
- (i) Pre-image resistance
- (ii) Compression
- (iii) Fixed length output
- (iv) None of the above
- Correct Answer: (iv) None of the above (Pre-image resistance, compression, and fixed-length output are all standard properties of cryptographic hash functions).
Question (c): ___ is a principle of data security.
- (i) Confidentiality
- (ii) Masquerading
- (iii) Confusion
- (iv) Diffusion
- Correct Answer: (i) Confidentiality
Question (d): Bitcoin is created by
- (i) Saifedean Ammous
- (ii) Satoshi Nakamoto
- (iii) Vitalik Buterin
- (iv) None of them
- Correct Answer: (ii) Satoshi Nakamoto
Question (e): The value of $3^{51} \bmod 5$ is
- (i) 1
- (ii) 2
- (iii) 3
- (iv) 4
- Correct Answer: (ii) 2 (By Fermat’s Little Theorem, $3^4 \equiv 1 \pmod 5$. Since $51 = 4 \times 12 + 3$, we have $3^{51} \equiv 3^3 \equiv 27 \equiv 2 \pmod 5$.)
Question (f): A node in blockchain environment is
- (i) a type of cryptocurrency
- (ii) a blockchain
- (iii) a computer on a network
- (iv) an exchange
- Correct Answer: (iii) a computer on a network
Question (g): ___ is used to store cryptocurrency.
- (i) Bank account
- (ii) Floppy disk
- (iii) Single central account
- (iv) Wallet Correct Answer: (iv) Wallet
Question (h): A computer program that validates and process blockchain transaction is
- (i) an adder
- (ii) a miner
- (iii) a mixer
- (iv) a manager Correct Answer: (ii) a miner
Question (i): A hot wallet is connected to Internet.
- (i) True
- (ii) False
- (iii) Depends on connectivity
- (iv) Internet is not an issue for using wallet Correct Answer: (i) True
Question (j): Hash functions are used in
- (i) cryptocurrency
- (ii) blockchain
- (iii) cryptography
- (iv) All of the above Correct Answer: (iv) All of the above
B.Tech 8th Semester Special Exam, 2022 (Code: 100816)
Question (a): A digital signature validates
- (i) confidentiality
- (ii) integrity
- (iii) authentication
- (iv) All of the above Correct Answer: (ii) integrity & (iii) authentication (Note for your readers: Strictly speaking, digital signatures provide authentication, integrity, and non-repudiation, but they do not provide confidentiality. In multiple-choice scenarios, choose the option that combines integrity and authentication, or point out the technical flaw in selecting “All of the above”.)
Question (b): The power to suspend/revoke digital signature certificate is vested in
- (i) commissioner
- (ii) certifying authority
- (iii) subscriber
- (iv) controller Correct Answer: (ii) certifying authority (The CA that issued the certificate has the primary ability to revoke it).
Question (c): The roots of the equation $y^{2}=x^{3}-4x$ are
- (i) 2 real and 1 imaginary
- (ii) all real
- (iii) all imaginary
- (iv) 2 imaginary, 1 real Correct Answer: (ii) all real (Solving $x^3 – 4x = 0 \Rightarrow x(x^2 – 4) = 0$, giving the roots $x=0, 2, -2$, which are all real).
Question (d): Elliptic curve cryptography follows the associative property.
- (i) True
- (ii) Partially true
- (iii) False
- (iv) None of the above Correct Answer: (i) True (Point addition in elliptic curve groups is associative).
Question (e): A block in blockchain consists of
- (i) nonce
- (ii) transactions
- (iii) hash of transactions
- (iv) All of the above Correct Answer: (iv) All of the above
Question (f): ___ is a process in computer science used to achieve agreement.
- (i) Consensus
- (ii) Reliability
- (iii) Safety
- (iv) Distribution Correct Answer: (i) Consensus
Question (g): Primarily hash functions are used for
- (i) authentication
- (ii) data integrity
- (iii) non-repudiation
- (iv) It depends on blockchain architecture Correct Answer: (ii) data integrity
Question (h): A cold wallet is connected to Internet.
- (i) True
- (ii) False
- (iii) Depends on connectivity
- (iv) Internet is not an issue for using wallet Correct Answer: (ii) False
Question (i): Bitcoin have a central authority.
- (i) Partially True
- (ii) True
- (iii) False
- (iv) Can be True or False Correct Answer: (iii) False
Question (j): ___ is a privacy protocol made to address the lack of privacy features of bitcoin.
- (i) Zerocoin
- (ii) Zero-encryption
- (iii) Zero-Hash
- (iv) Community authentication Correct Answer: (i) Zerocoin
VIIIth Semester Examination, 2023 (Code: 100816)
Question (a): In the future, Block chain applications will include
- (i) Only transaction involving crypto currencies.
- (ii) Only transaction between companies or government agencies.
- (iii) Crypto currency transactions, transactions between governments, companies and consumers, voting, healthcare and many other applications.
- (iv) Only transactions within the borders of 1 country. Correct Answer: (iii) Crypto currency transactions, transactions between governments, companies and consumers, voting, healthcare and many other applications.
Question (b): What best describes a blockchain?
- (i) A distributed ledger on a peer to peer network
- (ii) A Centralized Database
- (iii) An Exchange
- (iv) A type of Crypto currency Correct Answer: (i) A distributed ledger on a peer to peer network
Question (c): What is the maximum amount of Bitcoins that will ever be created?
- (i) Infinity, because there is no limit
- (ii) 21 million
- (iii) Nobody knows, because its created randomly
- (iv) Bitcoin isn’t real, so none will ever exist Correct Answer: (ii) 21 million
Question (d): What makes cryptocurrency secure?
- (i) Servers
- (ii) Cryptographic Math
- (iii) Government Banks
- (iv) Insurance Companies Correct Answer: (ii) Cryptographic Math
Question (e): Who introduced Bitcoin
- (i) The IMF
- (ii) Satoshi Nakamoti
- (iii) The Federal Reserve
- (iv) Stuart Haber Correct Answer: (ii) Satoshi Nakamoti
Question (f): Which of the following is true about the Bitcoin scripting language?
- (i) support infinite time/memory
- (ii) stack-based
- (iii) Turing complete
- (iv) None of the above Correct Answer: (ii) stack-based (It is deliberately non-Turing complete).
Question (g): What is the output of a cryptographic hash function?
- (i) A variable set of bits
- (ii) A fixed set of bits, derived from one-way mathematical operations
- (iii) An output that may be easily discovered by an adversary
- (iv) Outputs of such functions are of no importance Correct Answer: (ii) A fixed set of bits, derived from one-way mathematical operations
Question (h): Which hash function is used in Ledger?
- (i) SHA-64
- (ii) SHA-128
- (iii) SHA-256
- (iv) SHA-512 Correct Answer: (iii) SHA-256 (Assuming it refers to the Bitcoin ledger).
Question (i): Bitcoins are created as a reward for a process known as
- (i) Mining
- (ii) Wallet
- (iii) Bubble
- (iv) Ledger Correct Answer: (i) Mining
Question (j): Bitcoin have a central authority?
- (i) True
- (ii) False
- (iii) Can be true or false
- (iv) Can’t say Correct Answer: (ii) False
Special Examination, 2023 (Code: 100816)
Note: Many questions in this exam are repeats from the 2022 and 2023 regular papers. They are listed below with their verified answers.
- (a) Encryption is: (i) putting data into code making it difficult to read or understand
- (b) What best describes a blockchain? (i) A distributed ledger on a peer to peer network
- (c) ___ is a principle of data security: (i) Confidentiality
- (d) What makes crypto currency secure? (ii) Cryptographic Math
- (e) The value of $3^{51} \bmod 5$ is: (ii) 2
- (f) Which of the following is true about the Bitcoin scripting language? (ii) stack-based
- (g) ___ is used to store crypto currency: (iv) Wallet
- (h) Which hash function is used in Ledger? (iii) SHA-256
- (i) Bitcoin have a central authority? (ii) False
- (j) A hot wallet is connected to Internet: (i) True
B.Tech 8th Semester Examination, 2024 (Code: 100816)
Question (a): Which of the following is a primary goal of cryptography?
- (i) Data storage
- (ii) Data compression
- (iii) Data encryption
- (iv) Data retrieval Correct Answer: (iii) Data encryption
Question (b): In a blockchain, what is the purpose of a hash pointer?
- (i) To store transaction data
- (ii) To point to the next block
- (iii) To link the previous block and verify data integrity
- (iv) To encrypt transaction details Correct Answer: (iii) To link the previous block and verify data integrity
Question (c): What is the primary advantage of using a Merkle tree in blockchain?
- (i) Reduces the size of the blockchain
- (ii) Speeds up transaction processing
- (iii) Facilitates efficient and secure verification of large data sets
- (iv) Encrypts the entire blockchain Correct Answer: (iii) Facilitates efficient and secure verification of large data sets
Question (d): Which of the following statements is true about digital signatures?
- (i) Digital signatures provide data encryption.
- (ii) Digital signatures verify the integrity and authenticity of a message.
- (iii) Digital signatures are not used in cryptocurrency transactions.
- (iv) Digital signatures require the use of symmetric key algorithms. Correct Answer: (ii) Digital signatures verify the integrity and authenticity of a message.
Question (e): What is a key feature of the Elliptic Curve Digital Signature Algorithm?
- (i) It uses large prime numbers to generate keys.
- (ii) It is based on the hardness of integer factorization.
- (iii) It provides security using smaller keys compared to RSA.
- (iv) It does not involve public and private keys. Correct Answer: (iii) It provides security using smaller keys compared to RSA.
Question (f): In the context of cryptocurrencies, what does using public keys as identities mean?
- (i) Public keys are used to encrypt data for private communication.
- (ii) Public keys serve as unique addresses for users on the blockchain.
- (iii) Public keys are used to mine new cryptocurrency coins.
- (iv) Public keys are kept secret while private keys are shared publicly. Correct Answer: (ii) Public keys serve as unique addresses for users on the blockchain.
Question (g): What role does proof of work play in a blockchain network?
- (i) It ensures that all transactions are processed instantly.
- (ii) It provides incentives for participants to create new blocks.
- (iii) It eliminates the need for a distributed ledger.
- (iv) It simplifies the process of creating consensus without identity verification. Correct Answer: (ii) It provides incentives for participants to create new blocks.
Question (h): Which of the following best describes “consensus without identity” in the context of blockchain?
- (i) Using trusted third parties to verify transactions.
- (ii) Establishing consensus among participants without requiring them to reveal their identities.
- (iii) Assigning unique identities to all participants to prevent fraud.
- (iv) Allowing only known participants to join the network. Correct Answer: (ii) Establishing consensus among participants without requiring them to reveal their identities.
Question (i): In a decentralized system, how is data integrity typically maintained?
- (i) Through a single central authority.
- (ii) By using distributed ledger technology and consensus mechanisms.
- (iii) By storing data on local servers.
- (iv) Through manual verification by each participant. Correct Answer: (ii) By using distributed ledger technology and consensus mechanisms.
Question (j): What is the primary advantage of participating in a mining pool?
- (i) Increased anonymity for individual miners
- (ii) Higher chance of solving a block and earning rewards
- (iii) Reduced transaction fees for mined blocks
- (iv) Ability to use specialized mining hardware Correct Answer: (ii) Higher chance of solving a block and earning rewards
B.Tech 8th Semester Examination, 2024(S) (Special Exam)
(Note: The first question in this particular paper featured short-answer objective questions without multiple-choice options. I have provided direct one-sentence answers below.)
- (a) What is the ciphertext?
- Answer: Ciphertext is the encrypted or encoded version of plain text, rendering it unreadable without the proper decryption key.
- (b) How does hash pointer differ from a regular pointer?
- Answer: A regular pointer only indicates where data is stored, while a hash pointer also contains the cryptographic hash of that data, allowing you to verify that the data hasn’t been altered.
- (c) What is the role of a certificate authority (CA) in associating public keys with identities?
- Answer: A CA verifies the identity of an entity and issues a digital certificate that securely binds their identity to their public key.
- (d) What are the main types of cold storage used in cryptocurrency security?
- Answer: The main types of cold storage include hardware wallets, paper wallets, and offline computers.
- (e) What is liquidity?
- Answer: Liquidity refers to the ease and speed with which an asset or cryptocurrency can be bought or sold in the market without significantly affecting its price.
- (f) What is the block reward in Bitcoin mining?
- Answer: The block reward is a fixed amount of newly created Bitcoin awarded to the miner who successfully validates a new block, alongside any transaction fees.
- (g) How does local storage differ from server-side storage in terms of security?
- Answer: Local storage keeps keys exclusively on the user’s personal device, minimizing exposure to centralized hacks, whereas server-side storage entrusts keys to a third party, creating a single point of vulnerability.
- (h) What is a threshold scheme in key sharing?
- Answer: A threshold scheme (like Shamir’s Secret Sharing) divides a key into multiple pieces, requiring a minimum number (a threshold) of those pieces to be combined to reconstruct the original key.
- (i) What is a valid hash in Bitcoin mining?
- Answer: A valid hash is an output produced by the mining algorithm (SHA-256) that meets or falls below a specific target value determined by the network’s current difficulty.
- (j) What is the role of opcodes in Bitcoin Script?
- Answer: Opcodes are specific commands or operations (like OP_DUP or OP_CHECKSIG) used within Bitcoin’s stack-based scripting language to establish the conditions under which a transaction can be spent.
B.Tech 8th Semester Examination, 2025 (Code: 100816)
Question (a): Which of the following is a goal of cryptography?
- (i) Data mining
- (ii) Data redundancy
- (iii) Confidentiality
- (iv) Duplication Correct Answer: (iii) Confidentiality
Question (b): SHA-256 produces an output of:
- (i) 64 bits
- (ii) 128 bits
- (iii) 256 bits
- (iv) 512 bits Correct Answer: (iii) 256 bits
Question (c): A hash pointer points to:
- (i) Data only
- (ii) Hash of data only
- (iii) Encrypted key
- (iv) Both data and hash of data Correct Answer: (iv) Both data and hash of data
Question (d): What structure does a Merkle tree use to verify data?
- (i) Linked list
- (ii) Chain
- (iii) Binary tree
- (iv) Graph Correct Answer: (iii) Binary tree
Question (e): Which cryptographic technique is used in digital signatures?
- (i) Symmetric encryption
- (ii) Hashing
- (iii) Asymmetric encryption
- (iv) Compression Correct Answer: (iii) Asymmetric encryption
Question (f): The ECDSA algorithm is based on:
- (i) RSA
- (ii) Elliptic Curve Cryptography
- (iii) Hash trees
- (iv) Digital watermarking Correct Answer: (ii) Elliptic Curve Cryptography
Question (g): Consensus without identity is achieved in Bitcoin using:
- (i) IP tracking
- (ii) Identity verification
- (iii) Proof of work
- (iv) Digital tokens Correct Answer: (iii) Proof of work
Question (h): Bitcoin Script is:
- (i) Turing-complete
- (ii) Functional language
- (iii) Non-Turing complete
- (iv) Python-based Correct Answer: (iii) Non-Turing complete
Question (i): Hot wallets are typically:
- (i) Offline
- (ii) Connected to the internet
- (iii) Stored in paper form
- (iv) Invisible to exchanges Correct Answer: (ii) Connected to the internet
Question (j): Key splitting can be done using:
- (i) Shamir’s Secret Sharing
- (ii) AES encryption
- (iii) Hash functions
- (iv) Email forwarding Correct Answer: (i) Shamir’s Secret Sharing