CBSE Class 12 Computer Science HOTs Communication and Network

1 Mark Questions

Communication and Network Concepts

1 What is bleeding of signal?

2 Which communication medium is to be suggested for very effective and fast communication in guided medium?

3 In harsh industrial environment which cable would you like to use?

4 Which media have the ability to communicate over oceans?

5 What is the difference between microwave and radiowave transmission?

6 Which is the special case of microwave relay system?

7 Which transmission medium is useful for sparsely populated areas?

8 In which transmission medium Bandwidth allocation is limited?

9 What is baud?

10 Which network is easy to expand?

11 In which network there is no server?

12 In Ethernet card which connection is used for coaxial cable or twisted pair or for both?

13 Which device filter the data and which device can handle different protocol?

14 Which device do not control broadcast , filter traffic and filter collision?

15. Which networking device is used for less no. of nodes or which is for more no. of nodes?

4 Marks Questions

1. Knowledge Supplement Organisation has set up its new center at Mangalore for its office and web based activities. It has 4 blocks of buildings as shown in the diagram below:

e1)Suggest a cable layout of connections between the blocks.

e2) Suggest the most suitable place (i.e. block) to house the server of this organisation with a suitable reason.

e3) Suggest the placement of the following devices with justification

(i) Repeater

(ii) Hub/Switch

e4) The organization is planning to link its front office situated in the city in a hilly region where cable connection is not feasible, suggest an economic way to connect it with reasonably high speed?

Ans.1

(e2) The most suitable place / block to house the server of this organisation would be Block C, as this block contains the maximum number of computers, thus decreasing the cabling cost for most of the computers as well as increasing the efficiency of the maximum computers in the network.

(e3) (i) For Layout 1, since the cabling distance between Blocks A and C, and that between B and C are quite large, so a repeater each, would ideally be needed along their path to avoid loss of signals during the course of data flow in these routes. For layout 2, since the distance between Blocks A and C is large so a repeater would ideally be placed in between this path

(ii) In both the layouts, a hub/switch each would be needed in all the blocks, to interconnect the group of cables from the different computers in each block.

(e4) The most economic way to connect it with a reasonable high speed would be to use radio wave transmission, as they are easy to install, can travel long distances, and penetrate buildings easily, so they are widely used for  ommunication, both indoors and outdoors. Radio waves also have the advantage of being omni directional, which is they can travel in all the directions from the source, so that the transmitter and receiver do not have to be carefully aligned physically.

2. Ravya Industries has set up its new center at Kaka Nagar for its office and web based activities. The company compound has 4 buildings as shown in the diagram below:

e1) Suggest a cable layout of connections between the buildings.

e2) Suggest the most suitable place (i.e. building) to house the server of this organisation with a suitable reason.

e3) Suggest the placement of the following devices with justification:

(i) Internet Connecting Device/Modem

(ii) Switch

e4) The organisation is planning to link its sale counter situated in various parts of the same city, which type of network out of LAN, MAN or WAN will be formed? Justify your answer.

Ans.2. (e1) Any one layout

Layout option1

(e2) The most suitable place / block to house the server of this organisation would be Raj Building, as this block contains the maximum number of computers, thus decreasing the cabling cost for most of the computers as well as increasing the efficiency of the maximum computers in the network.

(e3)(i) Raj Building

(ii) In both the layouts, a hub/switch each would be needed in all the buildings, to interconnect the group of cables from the different computers in each block

e4) MAN, because MAN (Metropolitan Area Networks) are the networks that link computer facilities within a city.

3. “China Middleton Fashion” is planning to expand their network in India, starting with two cities in India to provide infrastructure for distribution of their product. The company has planned to set up their main office units in Chennai at three locations and have named their offices as “Production Unit”, “Finance Unit” and “Media Unit”. The company has its corporate unit in New Delhi. A rough layout of the same is as follows:

In Continuation of the above, the company experts have planned to install the following number of computers in each of their office units:

Production Unit  150

Finance Unit       35

Media Unit         10

Corporate Unit    30

i) Suggest the kind of network required (out of

LAN,MAN,WAN) for connecting each of the following office units:

• Production Unit and Media Unit

• Production Unit and Finance Unit

ii) Which one of the following devices will you suggest for connecting all the computers within each of their office units?

• Switch/Hub

• Modem

• Telephone

iii) Which of the following communication media, will you suggest to be procured by the company for connecting their local offices in Chennai for very effective (High Speed) communication?

• Ethernet cable

• Optical fiber

• Telephone cable

(iv) Suggest a cable/wiring layout for connecting the company’s local office units located in Chennai. Also, suggest an effective method/technology for connecting the company’s office unit located in Delhi.

Ans.3. (i)(a) Production Unit and Media Unit :MAN

(b)Production Unit and Finance Unit:LAN

(ii) Switch/Hub

(iii) Optical fiber

(iv) Optical Fiber/Star Topology Wireless/Satellite Link/Leased Line

Q.4. Nootan Vidya Mandir in OOTY is setting up the network between its different wings. There are 4 wings named as SENIOR(S), MIDDLE(M), JUNIOR(J) and OFFICE(O). Distance between the various wings are given below:

Wing O to Wing S      100m

Wing O to Wing M      200m

Wing O to Wing J       400m

Wing S to Wing M      300m

Wing S to Wing J       100m

Wing J to Wing M       450m

No. of Computers

Wing O       10

Wing S       200

Wing M      100

Wing J         50

(i) Suggest a suitable Topology for networking the computer of all wings.

(ii) Name the wing where the server to be installed. Justify your answer.

(iii) Suggest the placement of Hub/Switch in the network.

(iv) Mention an economic technology to provide internet accessibility to all wings.

Ans.4. (i) Star or Bus or any other valid topology.

(ii) Wing S, because maximum number of computers are located at Wing S.

(iii) Hub/ Switch in all the wings.

(iv) Coaxial cable/Modem/LAN/TCP-IP/Dialup/DSL/Leased Lines

or any other valid technology.

Q.5. Global Village Enterprises has following four buildings in Hyderabad city.

Computers in each building are networked but buildings are not networked so

far. The company has now decided to connect building also.

(a) Suggest a cable layout for these buildings.

(b) In each of the buildings, the management wants that each LAN segment gets a dedicated bandwidth i.e bandwidth must not be shared. How can this be achieved?

(c) The company also wants to make available shared Internet access for each ofthe buildings. How can this be achieved?

(d) The company wants to link its head office in GV1 building to its another office in Japan.

(i) Which type of transmission medium is appropriate for such a link?

(ii) What type of network would this connection result into?

Ans.5. (a) Total cable length required for this layout = 75 mts

(b) To give dedicated bandwidth, the computers in each building should be connected via switches as switches offer dedicated bandwidths.

(c) By installing routers in each building, shared internet access can be made possible

(d) (i) Satellite as it can connect offices across globe.

(ii) WAN ( Wide Area Network )