This set of Computer Networks Multiple Choice Questions & Answers (MCQs) focuses on “Internet”.
1. What is internet?
a) a single network
b) A collection of unrelated computers
c) interconnection of local area networks
d) interconnection of wide area networks
Answer: d
Explanation: The internet is a global network formed by connecting wide area networks (WANs), enabling worldwide communication and data sharing.
2. To join the internet, the computer has to be connected to a ________?
a) internet architecture board
b) internet society
c) internet service provider
d) different computer
Answer: c
Explanation: The ISPs (Internet Service Providers) are the main agents through which every computer is connected to the internet. They are licensed to allot public IP addresses to its customers in order to connect them to the internet.
3. Internet access by transmitting digital data over the wires of a local telephone network is provided by _______
a) leased line
b) digital subscriber line
c) digital signal line
d) digital leased line
Answer: b
Explanation: DSL (Digital Subscriber Line) is the technology designed to use the existing telephone lines to transport high-bandwidth data to service subscribers. DSL was used to allow the early users access to the internet and it provides dedicated, point-to-point, public network access.
4. ISP exchanges internet traffic between their networks by __________
a) internet exchange point
b) subscriber end point
c) isp end point
d) internet end point
Answer: a
Explanation: ISPs exchange internet traffic between their networks by using Internet Exchange Points. ISPs and CDNs are connected to each other at these physical locations are they help them provide better service to their customers.
5. Which of the following protocols is used in the internet?
a) HTTP
b) DHCP
c) DNS
d) DNS, HTTP and DHCP
Answer: d
Explanation: HTTP is used to browse all the websites on the World Wide Web, DHCP is used to allot IPs automatically to the users on the internet, and DNS is used to connect the users to the host servers on the internet based on the Domain Name.
6. The size of an IP address in IPv6 is _________
a) 32 bits
b) 64 bits
c) 128 bits
d) 265 bits
Answer: c
Explanation: An IPv6 address is 128 bits long. Therefore, 2128 i.e. 340 undecillion addresses are possible in IPv6. IPv4 has only 4 billion possible addresses and IPv6 would be a brilliant alternative in case IPv4 runs out of possible new addresses.
7. Internet works on _______
a) packet switching
b) circuit switching
c) both packet switching and circuit switching
d) data switching
Answer: a
Explanation: Packet switching is the method based on which the internet works. Packet switching features delivery of packets of data between devices over a shared network.
8. Which one of the following is not an application layer protocol used in internet?
a) remote procedure call
b) internet relay chat
c) resource reservation protocol
d) local procedure call
Answer: c
Explanation: Resource reservation protocol is a transport layer protocol used on the internet. It operates over IPv4 and IPv6 and is designed to reserve resources required by the network layer protocols.
9. Which protocol assigns IP address to the client connected in the internet?
a) DHCP
b) IP
c) RPC
d) RSVP
Answer: a
Explanation: DHCP stands for Domain Host Control Protocol. It is responsible to remotely assign IP address to the clients connected to the internet. The server that performs this fuction is called the DHCP server.
10. Which one of the following is not used in media access control?
a) ethernet
b) digital subscriber line
c) fiber distributed data interface
d) packet switching
Answer: d
Explanation: Packet switching is not really related to media access control as it just features delivery of packets of data between devices over a shared network. Internet is actually based on packet switching.
11. An interconnected collection of piconet is called ___________
a) scatternet
b) micronet
c) mininet
d) multinet
Answer: a
Explanation: Piconet is the basic unit of a bluetooth system having a master node and upto seven active slave nodes. A collection of piconets is called scatternet and a slave node of a piconet may act as a master in a piconet that is part of the scatternet.
12. In a piconet, there can be up to ________ parked nodes in the network.
a) 63
b) 127
c) 255
d) 511
Answer: c
Explanation: A slave node in a piconet can be instructed by the master node to go into parked mode. Then the slave node enters the parked mode in which the node is not disconnected from the network but is inactive unless the master wakes it up.
13. Bluetooth is the wireless technology for __________
a) local area network
b) personal area network
c) metropolitan area network
d) wide area network
Answer: b
Explanation: Bluetooth is a wireless technology used to create a wireless personal area network for data transfer up to a distance of 10 meters. It operates on 2.45 GHz frequency band for transmission.
14. Bluetooth uses __________
a) frequency hopping spread spectrum
b) orthogonal frequency division multiplexing
c) time division multiplexing
d) channel division multiplexing
Answer: a
Explanation: Frequency hopping spread spectrum is a method of transmitting radio signals by rapidly changing the carrier frequency and is controlled by the codes known to the sender and receiver only.
15. Unauthorised access of information from a wireless device through a bluetooth connection is called ________
a) bluemaking
b) bluesnarfing
c) bluestring
d) bluescoping
Answer: b
Explanation: Unauthorised access of information from a wireless device through a bluetooth connection is called Bluesnarfing. It is done through exploiting the vulnerabilities of the Bluetooth device to steal the transmitted information.
16. What is A2DP (advanced audio distribution profile)?
a) a bluetooth profile for streaming audio
b) a bluetooth profile for streaming video
c) a bluetooth profile for security
d) a bluetooth profile for file management
Answer: a
Explanation: A2DP stands for Advanced Audio Distribution Profile is a transfer standard use to transmit high definition audio through Bluetooth. It is mainly used in Bluetooth speakers and wireless headphones.
17. In a piconet, one master device ________
a) can not be slave
b) can be slave in another piconet
c) can be slave in the same piconet
d) can be master in another piconet
Answer: b
Explanation: In a scatternet, a slave node of one piconet may act as a master in a piconet that is part of the scatternet. The scatternet uses this property to connect many piconets together to create a larger network.
18. Bluetooth transceiver devices operate in ______ band.
a) 2.4 GHz ISM
b) 2.5 GHz ISM
c) 2.6 GHz ISM
d) 2.7 GHz ISM
Answer: a
Explanation: Bluetooth operates on 2.45 GHz frequency ISM band for transmission. It is used to create a wireless personal area network for data transfer up to a distance of 10 meters.
19. Bluetooth supports _______
a) point-to-point connections
b) point-to-multipoint connection
c) both point-to-point connections and point-to-multipoint connection
d) multipoint to point connection
Answer: c
Explanation: In Bluetooth, each slave node communicates with the master of the piconet independently i.e. each master-slave connection is independent. The slave is not allowed to communicate with other slaves directly.
20. A scatternet can have maximum __________
a) 10 piconets
b) 20 piconets
c) 30 piconets
d) 40 piconets
Answer: a
Explanation: A scatternet can have maximum of 10 piconets and minimum of 2 piconets. To connect these piconets, a slave node of one piconet may act as a master in a piconet that is part of the scatternet.
21. WiMAX stands for ___________
a) wireless maximum communication
b) worldwide interoperability for microwave access
c) worldwide international standard for microwave access
d) wireless internet maximum communication
Answer: b
Explanation: WiMAX or worldwide interoperability for microwave access is a set of wireless communication standards. It provides support for multiple physical layer (PHY) and Media Access Control (MAC) options. It is based on IEEE 802.16 standards.
22. WiMAX provides ________
a) simplex communication
b) half duplex communication
c) full duplex communication
d) no communication
Answer: c
Explanation: WiMax was developed to provide wireless broadband access to buildings. It can also be used to connect WLAN hotspots to the Internet. It is based on IEEE 802.16 standards.
23. WiMAX uses the _________
a) orthogonal frequency division multiplexing
b) time division multiplexing
c) space division multiplexing
d) channel division multiplexing
Answer: a
Explanation: WiMAX physical layer uses orthogonal frequency division multiplexing as it provides simplified reception in multipath and allows WiMAX to operate in NLOS conditions.
24. Which of the following modulation schemes is supported by WiMAX?
a) binary phase shift keying modulation
b) quadrature phase shift keying modulation
c) quadrature amplitude modulation
d) all of the mentioned
Answer: d
Explanation: WiMAX supports a variety of modulation schemes such as binary phase shift keying modulation, quadrature phase shift keying modulation, and quadrature amplitude modulation and allows for the scheme to change on a burst-by-burst basis per link, depending on channel conditions.
25. WiMAX MAC layer provides an interface between ___________
a) higher transport layers and physical layer
b) application layer and network layer
c) data link layer and network layer
d) session layer and application layer
Answer: a
Explanation: WiMAX provides support for multiple physical layer (PHY) on the physical layer and Media Access Control (MAC) options for higher layers to provide wireless broadband access to buildings.
26. For encryption, WiMAX supports _______
a) advanced encryption standard
b) triple data encryption standard
c) advanced encryption standard and triple data encryption standard
d) double data encryption standard
Answer: c
Explanation: Both advanced encryption standard and triple data encryption standard are block cipher techniques and are popularly used in WiMAX and other applications for secure encryption.
27. WiMAX provides _______
a) VoIP services
b) IPTV services
c) Both VoIP and IPTV services
d) no IPTV services
Answer: c
Explanation: IPTV can be transmitted over WiMAX, and relies on packet-switching to offer reliable delivery. VoIP can be operated over a WiMax network with no special hardware or software.
28. Devices that provide the connectivity to a WiMAX network are known as _________
a) subscriber stations
b) base stations
c) gateway
d) switch stations
Answer: a
Explanation: Subscriber stations in WiMAX are transceivers (transmitter and receivers). They are used to convert radio signals into digital signals that can be routed to and from communication devices. There is a variety of types of WiMAX subscriber stations like portable PCMCIA cards and fixed stations that provide service to multiple users.
29. WiMAX is mostly used for __________
a) local area network
b) metropolitan area network
c) personal area network
d) wide area network
Answer: b
Explanation: WiMAX provides Wi-Fi connectivity within the home or business for computers and smartphones. WiMAX network operators typically provide a WiMAX Subscriber Unit to do so. The subscriber unit is used to connect to the metropolitan WiMAX network.
30. Which of the following frequencies is not used in WiMAX for communication?
a) 2.3 GHz
b) 2.4 GHz
c) 2.5 GHz
d) 3.5 GHz
Answer: b
Explanation: The 2.4GHz ISM frequency band is used for personal area network technologies such as Bluetooth and hence is not suitable for WiMAX which is mostly used for Metropolitan Area Networks.
31. SONET stands for ___________
a) synchronous optical network
b) synchronous operational network
c) stream optical network
d) shell operational network
Answer: a
Explanation: SONET stands for synchronous optical network. Frame relay uses SONET to physically transmit data frames over a Frame Relay network as SONET is cheaper and provides better network reliability than other carriers.
32. In SONET, STS-1 level of electrical signalling has the data rate of _________
a) 51.84 Mbps
b) 155.52 Mbps
c) 2488.320 Mbps
d) 622.080 Mbps
Answer: a
Explanation: STS-1 level provides the data rate of 51.84 Mbps, STS-3 provides a data rate of 155.52 Mbps, STS-12 provides a data rate of 622.080 Mbps and STS-48 provides a data rate of 2488.320 Mbps.
33. The path layer of SONET is responsible for the movement of a signal _________
a) from its optical source to its optical destination
b) across a physical line
c) across a physical section
d) back to its optical source
Answer: a
Explanation: The path layer in SONET is responsible for the movement signal from the optical source to the optical destination. It is ideally expected to find the shortest and the most reliable path to the destination.
34. The photonic layer of the SONET is similar to the __________ of OSI model.
a) network layer
b) data link layer
c) physical layer
d) transport layer
Answer: c
Explanation: The photonic layer in SONET is like the physical layer of the OSI model. It is the lowest layer among the four layers of SONET namely the photonic, the section, the line, and the path layers.
35. In SONET, each synchronous transfer signal STS-n is composed of __________
a) 2000 frames
b) 4000 frames
c) 8000 frames
d) 16000 frames
Answer: c
Explanation: SONET defines the electrical signal as STS-N (Synchronous Transport Signal Level-N) and the optical signal as OC-N (Optical Carrier Level-N). The building block of SONET is the STS-1/OC-1 signal, which is based on an 8-kHz frame rate and operates at 51.84 Mbps.
36. Which one of the following is not true about SONET?
a) frames of lower rate can be synchronously time-division multiplexed into a higher-rate frame
b) multiplexing is synchronous TDM
c) all clocks in the network are locked to a master clock
d) STS-1 provides the data rate of 622.080Mbps
Answer: d
Explanation: In SONET, STS-N stands for Synchronous Transport Signal Level-N. STS-1 level provides the data rate of 51.84 Mbps, and STS-12 provides a data rate of 622.080 Mbps.
37. A linear SONET network can be ________
a) point-to-point
b) multi-point
c) both point-to-point and multi-point
d) single point
Answer: c
Explanation: Synchronous Optical Network (SONET) is basically an optical fiber point-to-point or ring network backbone that provides a way to accommodate additional capacity as the needs of the organization increase to multipoint networks
38. Automatic protection switching in linear network is defined at the _______
a) line layer
b) section layer
c) photonic layer
d) path layer
Answer: a
Explanation: The Line layer in SONET operates like the data link layer in the OSI model and it is responsible for the movement of signal across a physical line. The Synchronous Transport Signal Mux/Demux and Add/Drop Mux provide the Line layer functions.
39. A unidirectional path switching ring is a network with __________
a) one ring
b) two rings
c) three rings
d) four rings
Answer: b
Explanation: One ring is used as the working ring and other as the protection ring in which each node is connected to its respective adjacent nodes by two fibers, one to transmit, and one to receive.
40. What is SDH?
a) sdh is similar standard to SONET developed by ITU-T
b) synchronous digital hierarchy
c) sdh stands for synchronous digital hierarchy and is a similar standard to SONET developed by ITU-T
d) none of the mentioned
Answer: c
Explanation: SDH is a standard that allows low bit rates to be combined into high-rate data streams and as it is synchronous, each individual bit stream can be embedded into and extracted from high-rate data streams easily.
41. Real-time transport protocol (RTP) is mostly used in _________
a) streaming media
b) video teleconference
c) television services
d) all of the mentioned
Answer: d
Explanation: RTP stands for Real-time transport protocol and is for delivering audio and video over IP networks. Its applications include streaming media, video teleconference, and television services.
42. RTP is used to ________
a) carry the media stream
b) monitor transmission statistics of streams
c) monitor quality of service of streams
d) secure the stream
Answer: a
Explanation: RTP is used to carry the media stream for delivering audio and video over IP networks. Its applications include streaming media, video teleconference, and television services.
43. RTP provides the facility of jitter ____________
a) media stream
b) expansion
c) media modification
d) security
Answer: a
Explanation: RTP provides the facility of jitter media stream through a jitter buffer which works by reconstructing the sequence of packets on the receiving side. Then an even audio / video stream is generated.
44. Which protocol provides the synchronization between media streams?
a) RTP
b) RTCP
c) RPC
d) RTCT
Answer: b
Explanation: RTCP stands for Real-time Transport Control Protocol and it works with RTP to send control packets to the users of the networks while RTP handles the actual data delivery.
45. An RTP session is established for ____________
a) each media stream
b) all media streams
c) some predefined number of media streams
d) no media stream
Answer: a
Explanation: An RTP session is required to be established for each media stream for delivering audio and video over the IP network. Each session has independent data transmission.
46. RTP can use __________
a) unprevileleged UDP ports
b) stream control transmission protocol
c) datagram congestion control protocol
d) all of the mentioned
Answer: d
Explanation: RTP uses unprevileleged UDP ports, stream control transmission protocol, and datagram congestion control protocol for data delivery over IP networks.
47. Which one of the following multimedia formats can not be supported by RTP?
a) MPEG-4
b) MJPEG
c) MPEG
d) TXT
Answer: d
Explanation: RTP is suitable only for multimedia and not for simple text files as the operation would result into wastage of resources. Other protocols like FTP are suitable for such transmissions.
48. An RTP header has a minimum size of _________
a) 12 bytes
b) 16 bytes
c) 24 bytes
d) 32 bytes
Answer: a
Explanation: Each RTP packet has a fixed header of size 12 bytes that contains essential control information like timestamp, payload type etc. for the receiving system processing.
49. Which one of the following is not correct?
a) RTCP provides canonical end-point identifiers to all session participants
b) RTCP reports are expected to be sent by all participants
c) RTCP itself does not provide any flow encryption or authentication methods
d) RTCP handles the actual data delivery
Answer: d
Explanation: RTCP works with RTP to send control packets to the users of the networks and provide canonical end-point identifiers to all session participants while RTP handles the actual data delivery.
50. Which protocol defines a profile of RTP that provides cryptographic services for the transfer of payload data?
a) SRTP
b) RTCP
c) RCP
d) RTCT
Answer: a
Explanation: SRTP stands for Secure Real-time Transport Protocol. It is like an extension to RTP which provides stream security through encryption, message authentication and integrity, and replay attack protection.