1. An RPC (remote procedure call) is initiated by the _________
a) server
b) client
c) client after the sever
d) a third party
Answer: b
Explanation: Remote Procedure Call is a method used for constructing distributed, client-server applications based on extending the conventional local procedure calling where the client initiates an RPC to start a connection process.
2. In RPC, while a server is processing the call, the client is blocked ________
a) unless the client sends an asynchronous request to the server
b) unless the call processing is complete
c) for the complete duration of the connection
d) unless the server is disconnected
Answer: a
Explanation: While the server is processing the call i.e. looking through the specifications, the client is blocked, unless the client sends an asynchronous request to the server for another operation.
3. A remote procedure call is _______
a) inter-process communication
b) a single process
c) a single thread
d) a single stream
Answer: a
Explanation: Remote procedure calls is a form of inter-process communication where the client initiates an RPC to start a connection process. It is used to construct distributed, client-server applications.
4. RPC allows a computer program to cause a subroutine to execute in _________
a) its own address space
b) another address space
c) both its own address space and another address space
d) applications address space
Answer: b
Explanation: RPC allows a computer program to cause a subroutine to execute in another address space which is usually the servers address space in a conventional client-server network.
5. RPC works between two processes. These processes must be ____________
a) on the same computer
b) on different computers connected with a network
c) on the same computer and also on different computers connected with a network
d) on none of the computers
Answer: c
Explanation: For the operation of RPC between two processes, it is mandatory that the processes are present on the same computer and also on different computers connected with its network.
6. A remote procedure is uniquely identified by _________
a) program number
b) version number
c) procedure number
d) all of the mentioned
Answer: d
Explanation: Each remote procedure can be uniquely identified by the program number, version number and the procedure number in the networks scope. The identifiers can be used to control the remote procedure by parties involved in the process.
7. An RPC application requires _________
a) specific protocol for client server communication
b) a client program
c) a server program
d) all of the mentioned
Answer: d
Explanation: The RPC technique for constructing distributed, client-server applications based on extending the conventional local procedure calling. It requires a client program, a server program and specific protocol for client server communication to build the system.
8. RPC is used to _________
a) establish a server on remote machine that can respond to queries
b) retrieve information by calling a query
c) establish a server on remote machine that can respond to queries and retrieve information by calling a query
d) to secure the client
Answer: c
Explanation: RPC or Remote Procedure Call is used to establish a server on remote machine that can respond to queries and to retrieve information by calling a query by other computers.
9. RPC is a _________
a) synchronous operation
b) asynchronous operation
c) time independent operation
d) channel specific operation
Answer: a
Explanation: RPC is a synchronous operation where the remote machine works in sync with the other machines to act as a server that can respond to queries called by the other machines.
10. The local operating system on the server machine passes the incoming packets to the ___________
a) server stub
b) client stub
c) client operating system
d) client process
Answer: a
Explanation: The local operating system on the server machine passes the incoming packets to the server stub which then processes the packets which contain the queries from the client machines for retrieving information.
11. Which of the following is not an alternative name for symmetric key cryptography?
a) Secret key cryptography
b) Public key cryptography
c) Conventional encryption
d) Private key cryptography
Answer: b
Explanation: Cryptography is mainly categorized into two types; symmetric key cryptography and asymmetric key cryptography(public key cryptography). Symmetric key cryptography uses only one key for both encryption and decryption.
12. What is the cipher text for the text “GREET HER”, if Caesar Cipher is used(key=3)?
a) KVIIY LIV
b) KVIIX LIV
c) LWJJY MJW
d) JUHHW KHU
Answer: d
Explanation: Caesar cipher is the substitution cipher, which belongs to classical cryptography. Cipher text will be obtained by replacing the plain text letters with letters three places further from them. If further letter is ‘z’, then process will circularly follows ‘a’.
13. What is the cipher text for the message “TAKE ME TO THE PARTY”, id Rail Fence technique is used with two rows?
a) TKMTTEATAEEOHPRY
b) TAKEMETOTHEPARTY
c) TAEKMEOTTHPEARYT
d) YRPHOEEATAETTMKT
Answer: a
Explanation: Rail fence is the transposition technique, that belongs to classical cryptography. First the plain text is written in a sequence of diagonals with defined number of rows, then the cipher text is read off as a sequence of all the rows from starting to end.
14. What are the two broad categories of symmetric key cryptography?
a) Transposition and substitution
b) Classical and modern
c) Stream and Block
d) Classical and Block
Answer: b
Explanation: Symmetric key cryptography has two types; classical and modern. Classical cryptography again divided into two types; transposition and substitution. Modern cryptography is of two types; stream cipher and block cipher.
15. Which of the following algorithm does not belong to symmetric key ciphers?
a) DES
b) RC4
c) AES
d) Diffie-Hellman
Answer: d
Explanation: Diffie-Hellman is the first asymmetric cipher and well known for its logarithm computations. It is used at its best to transmit the secret key between users for further symmetric encryption of messages.
16. Which of the following is an advantage of symmetric cipher?
a) (N(N-1))/2 keys are required for N people
b) sharing secret key over communication channel
c) Brute force attack for small key size
d) Quick encryption and decryption
Answer: d
Explanation: Quick encryption and decryption is done in symmetric key cryptography. Because, it uses less resources and cipher text length will be small or same as plain text. It encrypts huge amount of data quickly and provides confidentiality.
17. Which of the following is incorrect about symmetric key cryptography?
a) It uses common key for both encryption and decryption
b) It is a secret key cryptography
c) It uses single fixed length key for each algorithm
d) Symmetric key can be combined with asymmetric key to achieve more security
Answer: c
Explanation: An algorithm can make use of number of random keys and the keys can be any size. If the key length is increased, then it will become difficult to crack the key.
18. Which of the following is a disadvantage of symmetric cipher?
a) Quick encryption
b) Less computational power
c) High level of security
d) Transmission of secret key
Answer: d
Explanation: Symmetric key cryptography uses single key to encrypt and decrypt messages. If the secret key is shared through an unsecured channel, then there will be a chance for attacking the key.
19. Which of the following is not an application of symmetric encryption algorithms.
a) Data security
b) Cloud storage
c) User privacy
d) Bitcoin’s block chain
Answer: d
Explanation: Unlike data security, cloud storage and user privacy, bitcoin uses elliptic-curve cryptography over symmetric key cryptography. Elliptic curve cryptography not only used for encryption, but also for digital signatures and random generators.
20. Asymmetric ciphers are complex than symmetric ciphers.
a) True
b) False
Answer: a
Explanation: Asymmetric ciphers are much complex and slower than symmetric ciphers. Asymmetric ciphers have longer keys, which are more related to mathematics. As two keys are employed in asymmetric cipher, it is complex than symmetric ciphers.
21. What are the two keys that are used in asymmetric key cryptography?
a) Secret key and private key
b) Private key and public key
c) Public key and secured key
d) Secured key and private key
Answer: b
Explanation: In asymmetric key cryptography, each user needs to have 2 keys; one is public and another one is private key. Public key is used for encryption, private is used for decryption.
22. Who are three discoverers of the RSA algorithm in public key cryptography?
a) Rivest, shamir, Aldleman
b) Routest, Shamir, adem
c) Robert, shamuel, alice
d) Radmir, shadhur, Alice
Answer: a
Explanation: RSA algorithm is a public key algorithm, which was discovered at M.I.T in 1978. It is very strong but the only disadvantage is, it requires more key length in order to provide more security.
23. What is the first public key cryptography algorithm?
a) RSA algorithm
b) AES algorithm
c) 3DES algorithm
d) Knapsack algorithm
Answer: d
Explanation: Knapsack is the first public key algorithm, that was not that much secured and now it is not in use. Knapsack is the founding algorithm for further algorithms in public key cryptography.
24. Which of the following is not a property of public key cryptography?
a) Uses different keys
b) Every user has a unique private key
c) Public key can be same for number of users
d) Cannot deduce private key from public key
Answer: c
Explanation: There will be a unique public key for every user, who publishes it. Public key prevents spoofing, by acting as the receiver. Sender uses the public key of the receiver to encrypt the message and the receiver will decrypt the message with his secret key.
25. What are the types in schemes of public key encryption?
a) RSA, EIGamal, Elliptic curve cryptography
b) Elliptic curve, RSA
c) RSA, EIGamal
d) EIGmal, RSA
Answer: a
Explanation: RSA is the initial one and it achieves security using factoring of huge numbers. EIGamal uses numbers module p to strengthen the algorithm. Elliptic curve scheme uses discrete logarithms to achieve security.
26. Which of the following is correct about RSA scheme in public key cryptography?
a) It is efficient for decryption
b) Lengthy keys are required for more security
c) It is not efficient for encryption
d) It is not popular
Answer: b
Explanation: RSA schemes need at least 1024 bits in a key for providing good level of security. Symmetric key cryptography uses 128 bits. The more the key length, more the security in RSA, this is why RSA slows down the system.
27. Which of the following is an asymmetric key cryptography algorithm?
a) DES
b) AES
c) RC4
d) RSA
Answer: d
Explanation: RSA is named with the first letters of the discoverers (Rivest, Shamir, Aldleman). It uses lengthy keys for security and uses the concept of factoring large numbers to be secured.
28. Which of the following doesn’t match as a property of elliptic curve cryptography?
a) Used over RSA
b) Uses elliptic curve theory
c) Key length is larger than RSA
d) Uses discrete logarithms
Answer: c
Explanation: Elliptic curve cryptography is much faster and efficient than RSA algorithm. And keys are smaller in size, which are generated by elliptic curve equation.
29. Which of the following is the disadvantage of asymmetric cryptography?
a) No need of key distribution
b) Security
c) Using digital signatures
d) Used to decrypt small messages
Answer: d
Explanation: Public key cryptography cannot deal well with bulk messages. It uses very lengthy keys compared to symmetric key cryptography; this makes the system slow to proceed with bulk messages.
30. A sender encrypts a message using recipient’s public key in public key cryptography?
a) True
b) False
Answer: a
Explanation: A sender can make use of pubic directory to acquire the public key of the recipient. After acquiring the public key of the receiver, sender will encrypt the message using receiver public key. If sender encrypts the message with his own secret key, then only the sender can decrypt it.
31. Which of the following equation is correct in case of hash function, where M = input, N = hash value, H = hash function?
a) H = M(N)
b) M = H(N)
c) N = H(M)
d) N = M(H)
Answer: c
Explanation: M is a block of data that is accepted by the hash function. Hash function(H) accepts the input and hash function will be performed. N is the fixed length of hash value of the block of input.
32. What is/are the property(s) of a good hash function in case of producing outputs for set of inputs?
a) Apparently random hash values
b) Evenly distributed hash values
c) Apparently random and evenly distributed values
d) Evenly distributed but not apparently random values
Answer: c
Explanation: When a huge set of input blocks are given to a hash function, a good hash function will result in unique random values with no relation between them. At the same all the hash values will be equal that is fixed length.
33. What is the core objective of the hash functions in producing hash values?
a) Integrity
b) Authenticity
c) Confidentiality
d) Security
Answer: a
Explanation: Integrity means retrieving the lost data as soon as possible. Hash functions accomplish integrity, because, even one bit is changed in the data, it will result in a change of hash value with high probability.