Data Communication and Computer Network 1


SKU: 907f26d135fa Category:

Assignment A

1). Explain critically the statement: “The channel from my VDU to the computer uses full duplex asynchronous transmission”.

2). Describe how a business might use an existing telephone network as a computer network? Describe some other commercial alternatives to telephone networks.

3). Why is multiplexing needed in data communication systems? Illustrate time division multiplexing and frequency division multiplexing.

4). A band of frequencies range from 100 to 190 KHz is being allocated for channels. Each channel is 5 KHz wide with a 1 KHz guard band. Sketch the channel assignments from 100 to 112 KHz.

5). With the help of a diagram, explain how an analog signal is converted to a digital signal?


Assignment B

1). Can we develop our own multimedia? If yes, explain with illustration, how?

2). What is MIDI? How MIDI can be used, also explain the way of connecting the devices to MIDI?

3). Why circuit switching is preferred over packet switching in voice communication? Explain.




Case Study

A) A system is designed to sample analog signals, convert them to digital form with a 4 bit converter and transmit them. What bit rate is required if the analog signal consist of frequencies between 400 Hz to 3400 Hz.

B) Illustrate the satellite communication system and calculate the order of delay in the above channel.


















Assignment C (Multiple choice Objective Questions)


Multiple Choice Questions


1. In FDM every user uses

A Same frequency band

B Different frequency band

C A frequency band which he is assigned at random

D None of the above


2. To know where on byte ends and the next one begins, the communications must establish—-

A Transmission Channel

B Transmission mode

C Transmission media

D Transmission mean


3. When data is sent during sent time periods, what do you call the transmission modes?

A Synchronous

B Asynchronous

C Protocol

D None of the above


4. What do you call the combination of video signals, voice signals and data signals?

A Teleconferencing

B The internet

C Bulletin board system

D Videoconferencing


5. When must you use a modem?

A When the communication link includes analog signals

B When you are using fiber optics

C When the bandwidth is wide

D All of the above


6. Communication that involves computer, establishing a link through the telephone system is called

A Teleprocessing

B Telecommunications

C Microprocessing

D None of the above


7. WAN hardware includes

A Multiplexors and routers


C Bridges and modems

D None of the above


8. For communications wide area network use

A Special purpose telephone wires

B Fiber optic cables and microwaves

C Both a and b

D None of the above


9. Modem EPABX use

A Space division multiplexing

B Time division multiplexing

C Frequency multiplexing

D None of the above


10. When computers are linked with a direct, high speed connection, what is the result called?

A Telecommunications

B A network

C A connection

D An information system


11. What are the two types of networks?


B Highway and systems

C Local area network and wide area network

D Both a and c


12. When do you call physical layout of a LAN?

A Connectivity

B Interface

C Bridge

D Topology


13. Since the advent of local area network, mainframe computers have

A Become less popular

B Become more popular

C Been unaffected

D Disappeared


14. A CB radio call is very much like

A Full duplex transmission

B Half duplex

C Quarter duplex

D No duplex


15. To send simultaneous voice and data signals, a LAN should use

A Twisted pair wire

B Baseband coaxial cable

C Broadband coaxial cable

D Two coffee cans with lots of strings.


16. A data highway is a good description of which network topology?

A Bus

B Star

C Ring

D Token ring


17. A dead workstation on a token ring network can cripple the network without

A Special software

B Wire centres or special bypass hardware

C Extra tokens

D A dead station token


18. A broad cast address enables a message to go to

A A single work station

B A single group of work stations

C Several groups of work stations

D A selected peripheral


19. A jam signal sent through a network means

A The network traffic is too congested.

B There has been a data collision

C It’s time to go

D The printer’s paper feeder is jammed


20. The IEEE 802.3 standard is most similar to

A IBM’s token ring network

B Xerox’s Ethernet LAN

C A generic star network

D A generic token ring network


21. For a relatively large network covering a long distance the best network topology would be

A Bus

B Token ring

C Token bus

D Super bus


22. Which of these is not a field in the Ethernet message packet?

A Type

B Data

C Zip code

D Address


23. Fast Ethernet has a maximum transmission speed of

A 10 mbps

B 25 mbps

C 50 mbps

D 100 mbps


24. Asynchronous transmission mode transmits

A Ethernet style packets

B X.25 switched packets

C 53 byte cells

D Very large frames for greater efficiency.


25. ATM can achieve a maximum speed of

A 100 mbps

B 500 mbps

C 1 gbps

D 1.2 gbps


26. Protocol is used to communicate between

A Similar module

B Dissimilar module

C Both a and b

D None of the above


27. Which of the following topology is least effected by removal/ addition of work stations?

A Ring

B Star

C Bus

D None of the above


28. Which one of the following is a guided transmission line?

A Pair of wires

B Optical fiber cable

C Coaxial cable

D All of the above


29. The following modulation requires the lowest bandwidth






30. Which of the following is associated with network?

A Node

B Star topology

C Both a and b

D None of the above


31. Satellite communications use

A Medium frequency band

B Microwaves

C Optical frequencies

D None of the above


32. Which of the following is not a guided transmission line?

A Pair of wires

B Wave guides

C Laser beam

D None of the above


33. Which of the following is the feature of multimedia?

A Sound

B Animation

C Picture

D All of the above


34. Multimedia can be used in which of the following fields?

A Education

B Entertainment

C Engineering

D All of the above


35. Maximum length of a data packet in packet switching method is

A 1 bytes

B 128-4096 bytes

C 10MB

D None of the above


36. Data transfer rate for LAN is normally

A 1-100 Mbps

B 1-2 Mbps

C 1-10 Mbps

D None of the above


37. Which of the following network is suitable for networking within a building?




D All of the above


38. Network disk drives are really

A Hard disk drives

B Network file servers

C Floppy disk drives

D Logical disk drives


39. Different network can be linked using

A A remote PC

B A disk server

C A router PC

D Spooled disk files


40. Users can shorten the set up of their network workstations environment by

A Using the NetWare manuals

B Using electronic mail

C Using elevator seeking

D Using login scripts