1. Fill in the blanks:
(a) The word 'communication' means sending and receiving data between two individuals or among many people.
(b) Telecommunication is a system of transmission of sounds, images, texts or data in the form ofelectronic signals
(c) The modes for transmitting data from one device to another are Simplex, Half duplex and full duplex.
(d) Bandwidth is measured in bps (bits per second)
(e) Fiber optical wire cable is used with a Straight Tip connector.
(f) TCP/IP is one of the oldest protocols of internet.
(g) MODEM is short form of modulator - demodulator.
(h) Linux is an example of network operating system.
(i) Computer network is a group of computers, in which a server acts as main computer.
(j) Microwave antenna requires line of sight to make communication.
2. State true or false:
(a) False
(b) True
(c) True
(d) True
(e) True
(f) True
(g) False
(h) False
(i) True
(j) True 3. Tick the best answer:
a. LAN
b. MS DOS
c. Switch
d. BNC
e. Fiber Optics
f. LAN
g. Modem
h. Gateway
i. Micro Waves
j. Simplex mode
k. can address many users
l. service of internet
4. Full forms:
a. WLAN = Wireless Local Area Network
b. WAN = Wide Area Network
c. STP = Shielded Twisted Pair
d. UTP = Unshielded Twisted Pair
e. POP = Post Office Protocol
f. NIC = Network Interface Card
g. HTTP = Hyper Text Transfer Protocol
h. MODEM = Modulator - Demodulator
i. SMTP = Simple Mail Transfer Protocol
j. BNC = British Naval Connector
k. VOIP = Voice Over Internet Protocol
l. FTP = File Transfer Protocol
m. IRC = Internet Relay Chat
n. ARP = Address Resolution Protocol
o. PPP = Point to Point Protocol
5. Match the following:
a) Protocol = Rules to exchange data
b) LAN= Network within a building
c) MAN= Network within a city
d) Coaxial = BNC
e) Cat 5 = RJ -45
f) Hub = central device for star topology
g) ISP = Service provider of internet
h) HTTP = Protocol
6. Technical Terms
a) Communication
b) Telecommunication
c) Medium
d) Half duplex
e) Full duplex
f) Bandwidth
g) Guided Media
h) Unguided Media
i) Computer Network
j) Topology
k) Repeater
l) Post Office Protocol (POP)
m) Router
n) MODEM
o) Protocols
p) e-commerce
q) Internet Telephony
r) Telnet7. Write Short notes :
a) Router : A router is an intelligent device that connects two different networks. It uses the address for filtering and forwarding the data. In addition, it can also provides additional features such as the ability to determine the best route for a destination.b) MODEM: MODEM is the short form of Modulator-Demodulator. This is a device used tp transfer the data of one computer to another using telephone lines. During the modulation phase, it is used to translate digital signals of a computer to analog signals, which then transmitted across the standard telephone line. The reverse takes place during its demodulation phase, as the MODEM receives analog signals from a phone line and converts into digital signals for the computer.
c) Repeater:The transmitted signals become weak due to some problem in the transmission mediums or the distance between the two locations. A repeater is a device that amplifies the incoming signals, creates a new copy of it and transmits the signals on the network. Repeaters are required in the network if the distance between two devices is long.
d) Hub:A hub is a device with multiple points or ports. It acts as a central point from where different computers and other devices are connected. It also amplifies the signals and sends them to all connected devices. The hub is mostly used in the physical star topology.
e) Star Topology: In a star topology, all computers or network devices are connected through a central device called hub or switch. The computers are connected to the hub or switch using unshielded twisted pair, shielded twisted pair or fiber optics cables. This is the most popular network topology used to connect computers and other devices in a network. In this topology, the central point device (hub or switch) may regenerate the signal, which helps to transfer data to a longer distance.
8. Answer in short:
a) Define Data.
Ans: A raw fact about anything which does not give any complete meaning is called data.b) What is Information?
Ans: The processed data which gives some or complete meaning is called information.c) In which mode communication television system works
Ans: Simplex moded) What is telent?
Ans: A program that allows the user to log into a remote computer on the internet as a user on that system is called telnet.e) Define e-commerce.
Ans: The activity of buying or selling goods and other online services using the internet is called e-commerce.f) What is topology?
Ans: The arrangement or connection pattern of computers or nodes and other devices of a network is a known as network topology.9. Answer the following questions:
a)Define data communication. What are the components of data communication?
Ans: The collection of hardware, software and other devices that allows to exchange data, information and voice between two or more devices through a wire or radio waves is called data communication. The Components of data communication are as follows: - Data - Sender - Medium - Receiver - Protocolb) Explain the different modes of data communication.
Ans:There are three main ways or modes for transmitting data from one device to another. They are: (i) Simplex Mode , (ii) Half-duplex Mode and (iii) Full-duplex Mode i. Simplex Mode : In this mode, transmission can take place in only one direction. It is called unidirectional transmission mode. The data or information is transmitted by only one device and other devices receive it. Television broadcast is an example of simplex mode of transmission. Other examples of simplex mode are TV broadcasting, Radio transmission, etc. ii. Half-duplex Mode : In this mode, data can be transmitted to both directions, but only to one direction at a time. It means half-duplex system can alternately send and receive data. Some suitable examples of half-duplex system are wireless, handset and walky-talky. iii. Full-duplex Mode: This mode allows simultaneous transmission of data to both directions. It allows both communicating devices to transmit and receive data simultaneously. A suitable example of full-duplex system is telephone system, where two people can communicate over a telephone. Both can talk as well as listen to each other at the same time in this system.c) Write any two differentiate between LAN and WAN.
| LAN | WAN |
|---|---|
| i) It is controlled or owned by a single organization. | i) It is controlled or owned by multiple organizations. |
| ii) The diameter is not more than a few kilometers. | ii) It covers a larger geographical area. |
| iii) Example: Network within a Room | iii) Example: Internet |
d) Define a computer network. Write any two advantages and disadvantages of it.
Ans: Two or more computers connected to each other to share data, hardware, software and other resources is called computer network.Two advantages of Computer Network:
i. Sharing of hardware and software resources ii. Communication becomes easy and cheaper.Two disadvantages of Computer Network:
i. Failure of server stops application being available. ii. The system opens to hackers.e) What are the three architectures of computer network? Write about the peer-to-peer architecture.
Ans: 1. Centralized Computing network 2. Client Sever network 3. Peer to Peer NetworkPeer to Peer Network
- The technique of data transmission from node to fashion in which each node behaves like as server or host temporarily is called peer to peer architecture. - There is no client or good and powerful server. - In the peer network the network users simply share disk space and other resources.f) What is client-server architecture of computer network? Write any three features of it.
Ans: The client–server network consists at least one server and one or more clients or workstations, where users do their work. The server is the main computer, which gives services to the workstations.Three features of client server architecture:
1. The network in which the all workstations or nodes are connected with main server. 2. The data sent by any computer, at first reaches to server, and then passed to each workstation. 3. The star topology is the suitable example of client server architecture.g) What is a protocol? Write the name of protocols work for email.
Ans: Sets of rules that the computers on the network must follow to communicate and to exchange data with each other is called protocol. SMTP - Pushes mails to the server POP - Pulls mails from the serverh) What is NIC? Write its function in a computer network.
Ans: A hardware device that acts as an interface through which a computer is connected to a network is called Network Interface Card (NIC) . Each NIC is assigned a unique MAC (Media Access Control) address by the manufacturer. The role of NIC in a computer network is to convert data into electrical signals and transfer them through cables and vice - versa.i) Draw a diagram of the star topology and label the important components.
j) Draw a figure of bus topology. Write any two advantages and disadvantages of it.
Advantages of Bus Topology:
1. It is easy to set up computers and other devices in bus topology, because all the devices are connected through a single wire. 2. It requires fewer cable media, so it is cheaper than other topologies.Disadvantages of Bus Topology:
1. The whole network system collapses if the cable or backbone is damaged. 2. It is difficult to detect the errors in this network.k) Write the advantages and disadvantages of the star topology.
Ans:Advantages of Star Topology:
1. It is easy to set up and configure. 2. Failures of a single computer or cable does not affect the entire network.Disadvantages of Star Topology:
1. It requires more cable in comparison to bus topology. So , it is costlier. 2. Failures of the central device (switch or hub) break down the whole system.l) Differentiate between peer to peer and client server architecture.
| Peer to Peer | Client Server |
|---|---|
| (i) Clients and server are not distinguished; each node acts as client and server. | (i) There is a specific server and specific clients connected to the server. |
| (ii) The data is stored in a centralized server. | (ii) Each peer has its own data. |