• Class: Eight

    Chapter 1: Network

    Exercise Solution

    1. Fill in the blanks:

    a) Apache is an open source web server.
    b) Wireless-Fidelity is a mode of communication that is establishedby using radio frequency technology.
    c) A Webpage contains one or more web pages which are linked with each other.
    d) Bluetooth's PAN are also known as Piconets.

    e) A link to a different section of the same webpage is known as Named Anchor.

    2. Select the most suitable alternative:

    a) In LAN, data communication takes place at the rate of:
    (i) 100-1000 mbps          (ii) 10-20 mbps      (iii) 10-1500 mbps       (iv) None of these

    b) In this type of cable, data are transferred through electromagnetic waves:
    (i) Ethernet cable             (ii) Coaxial cable      (iii) Fibre optic            (iv) None of these

    c) It develops a network conectivity for locations within a distance of 100 mts:
    (i) Infrared                (ii) Wi-Fi                   (iii) Bluetooth                 (iv) None of these

    d) It includes drawings, paintings, scanned images, photographs, steel and video images:
    (i) Graphics             (ii)Audio                    (iii) Animation                  (iv) None of these

    e) In this type of network there is no specific tariff to be followed for its usage:
    (i) WAN                  (ii) MAN                     (iii) LAN                          (iv) None of these

    f) The centralized computer having huge storage capacity and very high processing speed are called as:
    (i) Server                (ii) Workstation           (iii) Tree                     (iv) Mesh

    g) The documents in websites that display information are called as:
    (i) Server                (ii) Webpage              (iii) ISP                       (iv) LAN

    3. Differentiate between the following:

    a) LAN and WAN

    Answer: LAN stands Local Area Network. In this type of network, computers are connected in a local unit or small geographical area. In LAN, data communication takes place at a rate of 100-1000 mbps. It is owned by an individual or an organization. There is no specific tariff for its usage.

    WAN stands Wide Area Network. In this type of network, computers are connected over large geographical area at less cost. In WAN, data communication takes place at a rate of 150 mbps. The common example of WAN is ‘Internet’.

    b) Ethernet and Co-Axial cable

    Answer: Ethernet is a computer networking technologies that connects LAN, MAN and WAN. It is a data link technology which generally use wired local area networks (LANs) and enables the device to communicate with each other.

    Co-Axial cable is an efficient electrical transmission media. It consists of a single line of conductor surrounded by an insulation layer and a conductive shield over it. Its transmission rate is 100 Mbps and bandwidth upto 400 Mhz.

    c) Bluetooth and Wi-Fi

    Answer: Bluetooth is a wireless network connectivity based on radio waves technology to communicate over a short range. It consumes less power and can communicate upto 100 meters.

    Wireless Fidelity is a wireless network connectivity established by radio frequency like Bluetooth but has stronger connection within 150 meters. It is also called “Wireless Ethernet”.

    4. Expand the abbreviations:

    a) TCP/IP      :   Transmission Control Protocol / Internet Protocol

    b) Wi-Fi        :    Wireless Fidelity

    c) RFC          :   Request for Comments

    d) WiMax      :    Worldwide Interoperability for Microwave Access

    e) ISP          :     Internet Service Providers

    f) NIU           :     Network Interface Unit

    g) MAC         :    Media Access Control

    h) CAN         :    Controller Area Network

    i) IMAP         :     Internet Message Access Protocol

    j) FTP           :    File Transfer Protocol

    5. Suggest the answer in one word only:

    a) Rajat wanted to establish network connection in his office so that employee of his organization can share the files and resources among themselves. Which type of network connection should he established to do so?

    Answer: Local Area Network.

    b) A company is opening its branch in a metropolitan city where they will give free services to their customer and also try to resolve their problem through phone calls. Which type of cable they should use so that they can achieve high bandwidth and high data transmission?

    Answer: Co-Axial Cable.

    c) Lakshya bought a new laptop and wanted to transfer some music and sound files which is stored in his mobile phone. Is it possible to transfer these files through wireless mode? If it's so then which facility does his mobile and computer should have to make those type of task possible?

    Answer: Yes. Bluetooth or Wi-Fi.

    6. Answer the following questions:

    a) What does the term Networking means in context to computer? Explain its advantages.

    Answer: The interconnection, as over communication media, of two or more than two computers to access and share information or resources between themselves is known as Networking. Each computer over network is called “Node”. It is also known as Workstation.

    Advantages of computer networking is as follows:

    File Sharing: Networking enables to easily share any type of data or information between nodes.

    Resource Sharing: It allows to use network-connected devices like printers, scanners etc. or share software between multiple workstations.

    Fast Delivery of Information: Networking helps in instant delivery of Information. File and resource sharing enables to save more time and effort.

    Cost Efficient: Networking has considerably reduced the expenses over data transfer and peripheral devices.

    b) What are the different types of Network? Explain their characteristics.

    Answer: Based on geographical area following are the types of Network:

    1. Local Area Network (LAN)
    2. Metropolitan Area Network (MAN)
    3. Wide Area Network (WAN)

    Characteristics of LAN:

    • It is smallest network in comparison of MAN and WAN.
    • Its geographical area is limited upto a building or small campus.
    • Data Communication rate of LAN is 100-1000 Mbps.
    • For data transfer, there is high bandwidth.
    • It is typically owned by an individual or an organization.

    Characteristics of MAN:

    • It covers a larger area than a LAN but a smaller area than a WAN.
    • It is confined to a specific town, city or region
    • Data Communication rate of MAN is upto 100 Mbps.
    • For data transfer, there is a moderate bandwidth.
    • It can be owned publicly or privately.

    Characteristics of WAN:

    • It is largest type of network.
    • It covers a larger geographical area, such as a continent, a state or a country.
    • It has lower Data Communication rate of 10-20 Mbps.
    • For data transfer, there is low bandwidth.
    • It has distributed ownership model.

    c) What are the common types of media used in guided networking? Explain them briefly.

    Answer: Common types of media used in guided networking are as follows:
    a) Ethernet Cable: It is used in in Local Area Network. It enables transmission speed of 100-1000 Mbps. The amount of data transmission depends on the quality of ethernet cable. It can be categorized into Straight Through Ethernet Cable and Crossover Ethernet cable.
    b) Coaxial Cable: It consists of a single line of conductor surrounded by an insulation layer and a conductive shield over it. It has a transmission rate of 100 Mbps that maintains bandwidth upto 400 Mhz. It is commonly used by cable operators in LAN.
    c) Optical Fiber Cable: In Fiber optics cable, data are transferred through electromagnetic waves. Using optical fibers, one can achieve a bandwidth of 20 Ghz and transmission rate upto 10 Gbps.

    d) Name the wireless network technologies used these days. Explain about their working.

    Answer: Followings are the wireless network technologies used these days:
    a) Infrared: Infrared (IR) is a wireless communication technology used over short range. IR communication has major limitations because it requires line-of-sight, has a short transmission range (few feet) and is unable to penetrate walls.
    b) Bluetooth: Bluetooth is a short-range wireless communication technology that allows devices such as mobile phones, computers and peripherals to transmit data or voice wirelessly over a short distance. Bluetooth employs radio waves for communication. It consumes less power and the physical range of transmission is up to 100 metres.
    c) Wireless-Fidelity (Wi-Fi): It is a mode of communication network that is established by radio frequency (RF) but has more power resulting into a stronger connection. It is also called “Wireless Ethernet”. It is used to establish network in offices or within the small campus of an organisation.

    e) List the advantages of cloud computing.

    Answer: Advantages of cloud computing are as follows:
    a) Cost Saving
    b) Reliability
    c) Productivity
    d) Performance
    e) High Speed

    7. Suggest the solution for given situation in one word/line:

    a) One day when Rahul went to his computer lab and saw that all the computers were connected to a single printer and whoever is giving a command to print, the print out comes from that printer. Can you name the concept of communication?

    Answer: Networking.

    a) Two friends were talking to each other about their mobile. One of them heard his favourite song in other friend’s mobile. He requested to copy those songs in his mobile too. Suggest the most appropriate way to transfer data without using wire.

    Answer: Wireless-Fidelity (Wi-Fi).

    8. Write sort notes on:

    a) Workstation

    Answer: It refers to the computer connected in a network. Workstation is also known as Node.

    b) Network Interface Unit

    Answer: Network Interface Unit is a device attached to each node. It acts as a common interface to establish connection between networked computers to connect to an outside network. It is also known as Network Interface Card.

    c) Modem

    Answer: It stands for Modulator-Demodulator. It is a peripheral device which modulates (convert digital signals into analog signals) from transmitting workstation and demodulates (convert analog signals into digital signals) at the recipient’s workstation.

    d) Switch

    Answer: Switch is a small hardware device that is used to amplify data signals and create a smaller network segment or several subnets of bigger network. It is used to prevent overloading of data in the traffic of a network. It is also responsible for forwarding and transforming data packets between the sub networks.

    e) Web Portal

    Answer: A web portal is a specially designed website that brings information from diverse sources, like emails, online forums and search engines, together in a uniform way. It is a website that provides a broad array of services, such as search engines, e-mail, online shopping, etc.

    f) Hub

    Answer: Hub is hardware device which is commonly used to connect several devices together in a LAN (Local Area Network). It contains multiple ports. It acts as a common connection point for devices in a network. It can be either Active or Passive. It is also known as “Repeater”.

    g) Router

    Answer: It is an electronic device that has the ability to connect LAN which have different protocol. Router forwards packets over network on the basis of address of destination.

    h) Hyperlink

    Answer: A hyperlink is a word, phrase, or image that enables to link webpages. It enables to jump to a new document or a new section within the current document.

    i) Bandwidth

    Answer: It refers to the speed of transfer of data over a network. It represents the capacity of a network for supporting data transfers. It is expressed in Bits Per Second.

    j) Cloud Computing

    Answer: Cloud computing is the on-demand availability of computer system resources, especially data storage and computing power, without direct active management by the user. The term is generally used to describe data centers available to many users over the Internet.