Computer Network MCQ
1) Which of these is a standard interface for serial data transmission?
Answer: (b) RS232C
Explanation: The RS232C is a standard interface for serial data transmission that defines the protocol and physical interface for transmitting serial data fairly easily between associated appliances and computers.
2) Which type of topology is best suited for large businesses which must carefully control and coordinate the operation of distributed branch outlets?
Answer: (d) Star
Explanation: The star topology is the best network topology for large businesses because it is simple to control and coordinate from the central computer.
3) Which of the following transmission directions listed is not a legitimate channel?
Answer: (d) Double Duplex
Explanation: Double duplex is not a legitimate channel for transmission in computer network.
4) "Parity bits" are used for which of the following purposes?
Answer: (c) To detect errors
Explanation: The parity bit is also known as the check bit, and has a value of 0 or 1. It is used for error detection for blocks of data.
5) What kind of transmission medium is most appropriate to carry data in a computer network that is exposed to electrical interferences?
Answer: (b) Optical fiber
Explanation: The optical fiber is made of glass or plastic. In this cable, the transmission of data occurs in the form of light rather than the electric current, so this cable provides higher data transfer speed than other cables.
6) A collection of hyperlinked documents on the internet forms the ?.?
Answer: (a) World Wide Web (WWW)
Explanation: World Wide Web (WWW) creates a collection of hyperlinked documents on the Internet.
7) The location of a resource on the internet is given by its?
Answer: (b) URL
Explanation: A URL (Uniform Resource Locator) is a database connection that describes the database's location on a computer network and the retrieval process. A URL is a different form of URI (Uniform Resource Identifier) although the two words are used interchangeably by many people.
8) The term HTTP stands for?
Answer: (c) Hypertext transfer protocol
Explanation: The term HTTP stands for Hypertext transfer protocol.
9) A proxy server is used as the computer?
Answer: (a) with external access
Explanation: A proxy server is a computer that acts as a gateway between a user's computer and the Internet. The proxy server is also called application level gateway. By this the client computer can establish indirect network connection to another network.
10) Which one of the following would breach the integrity of a system?
Answer: (b) Full access rights for all users
11) Which software prevents the external access to a system?
Answer: (a) Firewall
Explanation: A firewall is a network securing software that prevents unauthorized users and dangerous elements from accessing the network. Software firewall acts as a filter for our network which prevents harmful information.
12) Which one of the following is a valid email address?
Answer: (a) firstname.lastname@example.org
Explanation: A proper email address is a combination of the email prefix and email domain, both in appropriate formats. The domain appears to the right side of the @ symbol and the prefix appears to the left side of the @ symbol.
For example, in this email address email@example.com, "javat" is the prefix, and "point.com" is the domain.
13) Which of the following best describes uploading information?
Answer: (b) Sending information to a host computer
14) Which one of the following is the most common internet protocol?
Answer: (c) TCP/IP
Explanation: TCP/IP is the most common internet protocol because it is the most widely used network protocol.
15) Software programs that allow you to legally copy files and give them away at no cost are called which of the following?
Answer: (d) Public domain
Explanation: Public domain software can be modified, distributed or sold by anyone without any attention, but no one can ever own it.
16) The term FTP stands for?
Answer: (c) File transfer protocol
Explanation: The term FTP stands for File transfer protocol.
17) At what speed does tele-computed refer?
Answer: (c) Baud rate
Explanation: In telecommunication, baud rate is a specific unit of the speed rate. It is one of the significant functions that determine the speed of the communication over the data channel.
18) Which one of the following is not a network topology?
Answer: (d) Peer to Peer
Explanation: Peer to Peer network is a network to which all computers are used the same resources and rights as other computers. Its network designed primarily for the small local area.
19) The maximum length (in bytes) of an IPv4 datagram is?
Answer: (c) 65535
20) Which of the following statements could be valid with respect to the ICMP (Internet Control Message Protocol)?
Answer: (b) A redirect message is used when a router notices that a packet seems to have been routed wrongly.
21) The IP network 192.168.50.0 is to be divided into 10 equal sized subnets. Which of the following subnet masks can be used for the above requirement?
Answer: (c) 255.255.255.0
Explanation: This address belongs to class C, so 8 bits are reserved for the host ID. 24 bits are reserved for network ID.
22) When the mail server sends mail to other mail servers it becomes ___ ?
Answer: (a) SMTP client
Explanation: The SMTP client is an organization that allows sending emails using the SMTP server. SMTP servers can't send emails to other SMTP servers separately. It is based on client-server architecture.
23) The length of an IPv6 address is?
Answer: (c) 128 bits
Explanation: An IPv6 address is 128 bits long, which has 2^128 address space.
24) Consider the following:
Which of the above is consider as (a) signal transmission medium is data communications?
Answer: (c) (1) (2) and (5)
25) Which of the following address belongs class A?
Answer: (a) 220.127.116.11
Explanation: 18.104.22.168 address belongs the class A because the first octet value of this address lies between 0 and 127.
26) Which of the following is correct IPv4 address?
Answer: (e) 22.214.171.124
Explanation: 126.96.36.199 is correct IPv4 address because IPv4 is a standard numbering system that uses four integers from 0 to 255. The IP address is a group of numbers that identify user system on the network.
27) Which of the following IP addresses can be used as (a) loop-back addresses?
Answer: (b) 127.0.0.1
Explanation: A loopback address is a special IP address whose IP address is between 127.0.0.1 to 127.255.255.255. It is reserved for loopback. It doesn't require a physical connection to a network.
28) The term WAN stands for?
Answer: (c) Wide Area Network
Explanation: The term WAN stands for Wide Area Network.
29) Which of the following cannot be used as a medium for 802.3 ethernet?
Answer: (c) A microwave link
Explanation: A microwave link cannot be used as a medium for 802.3 ethernets, because a microwave link is a transmission network that utilizes a beam of radio waves in the microwave frequency spectrum to relay video, audio, or data between two places.
30) What IP address class allocates 8 bits for the host identification part?
Answer: (c) Class C
Explanation: In class C only, 8 bits are reserved for the host ID, and 24 bits are reserved for network ID.
31) The term IANA stands for?
Answer: (a) Internet Assigned Numbers Authority
Explanation: The term IANA stands for Internet Assigned Numbers Authority.
32) How many versions available of IP?
Answer: (c) 2 version
Explanation: There are only two IP versions are avilable in the present: IP version 4 (IPv4) and IP version 6 (IPv6).
33) Which layer of the TCP / IP stack corresponds to the OSI model transport layer?
Answer: (a) Host to Host
Explanation: The host to host layer conforms the transport layer of the OSI model. This layer is responsible for the final correspondence and error-free distribution of data.
34) An Aloha network uses an 18.2 kbps channel for sending message packets of 100 bits long size. Calculate the maximum throughput.
Answer: (c) 0.6027
Explanation: In Pure Aloha, Efficiency = 18.4%
Usable bandwidth for 18.2 kbps = 18.2 * 0.18 = 3.276 kbps
Therefore, the maximum throughput of Pure Aloha
= 1/2e * 3.276
= (18.4 * 3.276) / 100
35) On a simplex data link, which of the following is a possible error recovery technique?
Answer: (b) The use of hamming codes
Explanation: The hamming codes is an error recovery technique that can be used to detect and correct the errors. It was developed by R.W. Hamming.
36) Which of the statement is correct with regard to Time Division Multiplexing (TDM) and its variants?
Answer: (a) and (b)
37) The term IPv4 stands for?
Answer: (a) Internet Protocol Version 4
Explanation: The term IPv4 stands for Internet Protocol Version 4.
38) The term LAN stands for?
Answer: (b) Local Area Network
Explanation: The term LAN stands for Local Area Network.
39) Which of the through is share the data of two computer?
Answer: (b) Network
Explanation: There are many ways to share data between two computers, but a network connection is established before data sharing.
40) In specific, if the systems use separate protocols, which one of the following devices is used to link two systems?
Answer: (b) Gateway
Explanation: If the system used separate protocols, gateway device is used to link two systems.
41) How many digits of the Data Network Identification Code (DNIC) identify the country?
Answer: (a) first three
Explanation: The first three digits of the Data Network Identification Code (DNIC) is identify the country (first digit to identify a zone and other two digits to identify the country within the zone).
42) Which of the following methods is used to broadcast two packets on the medium at a time?
Answer: (a) Collision
Explanation: A collision occurs when two or more computers are attempting to transfer data across a network at a time.
43) Which of the following is true with regard to the ping command?
Answer: (c) Ping summarizes the packet loss and round-trip delay between two IP end points.
44) The private key in asymmetric key cryptography is kept by?
Answer: (b) Receiver
Explanation: Only the receiver keeps the private key. Its purpose is to ensure that the message can only be decrypted by the intended receiver.
45) Which of the following algorithms is not used in asymmetric-key cryptography?
Answer: (c) Electronic code book algorithm
Explanation: An electronic code book algorithm is a mode of operation for a block cipher, where each frame of text in an encrypted document refers to a data field. In other terms, the same plaintext value would also give the same value for ciphertext.
46) In the cryptography, the sequence of the letters is rearranged by?
Answer: (a) Transposition ciphers
Explanation: A predefined technique shuffles the sequence of letters in a plaintext message in the transposition ciphers.
47) What is the maximum efficiency of pure aloha at G = 1/2?
Answer: (d) 18.4
Explanation: The maximum efficiency of pure aloha formula is G * e-2G.
Given, G =1/2
=1/2 x e-2 x 1/2
= 1 / 2e
48) What is the maximum efficiency of slotted aloha at G = 1?
Answer: (a) 36.8
Explanation: The maximum efficiency of slotted aloha formula is G * e-G.
Given, G = 1
= 1 x e-1
= 1 / e
49) Which of the following statement is true about error detection techniques used on communications link?
Answer: (d) All of the these
50) The correct order of corresponding OSI layers for having functionalities of routing and reconciling machine representation differences with shared access resolution and ASCII test protocol is?
Answer: (c) Network, Presentation, Data link, Application