Introducing Computer Networks and Loval Area Networks

9th grade Unit 1 : Computer Networks: the LAN AY 2016/2017

Pioneer Middle School of Sfax 9 Teacher: Mrs. IMEN TEKAYA BOUAZIZ

I- Computer Networks

I-1 – Presentation of a computer network: Task1: Observe carefully these figures and describe them.

PIONEER MIDDLE

SCHOOL OF SFAX:

THE 9th LEVEL Lesson 2: INTRODUCING THE

LOCAL AREA NETWORK

9th level Unit 1 : Computer Networks: the LAN AY 2015/2016


* Terminals, and communication devices: iPad; iphone; smart phones; e-book; PSP;smart TV; …

**wires, cables, or a telecommunication system: are means of connection (physical links) through wires or wireless connection.

A network is a system of interconnected computers and peripherals (such as printers, scanners, network cards, modems, routers, work stations); it can consist of as few as two computers or millions of computers that are spread over a large geographical area connected (linked) by different types of physical links (for example, optical fiber cable, coaxial cable, telephone line, satellite transmission, radio waves, Wi-Fi, blue-tooth, infra-red, etc.) allowing the movement (the transfer, the transmission) or the exchange of information between one center to the other; and the sharing of hardware and software resources.

So, Some of the primary reasons ( the purposes ) for networking PCs are as follows:

To provide services and Sharing files, Sharing printers and other devices in order to reduce the equipment costs, Enabling common administration and security, Supporting network applications such as Electronic mail or videoconferencing or groupware, etc, and Sharing Databases services.

Task 3: According to the previous task and pictures, what are the components of a computer network?

A network computer is composed of :

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A computer network is a system of two or more ………………, terminals, and

communication devices* linked (……………..) by …………, cables, or a telecommunication

system** in order to …………….. software resources (data, files, programs, applications)

or hardware resources (printer or scanner, etc) and …………………….information. It allows

computers to ……………………. with each other. The purpose is to provide services and to

reduce distances and equipment costs.

Task 2: According to the last task, define a computer network.

Complete the following definition with words from this list: information, exchange, computers, connected, communicate, wires, share

Observations



I-2 – Types of computer networks:

A- Types of computer networks according to the geographic scale: It depends on how much large is the area where it spans.

Task4: Fill in the blanks with the correct words.

Local Area Networks (LAN) is a network

that is confined to a relatively ………….. area.

It is generally limited to a geographic area such

as a lab, school, or building.

The defining characteristics of LANs include their …………………… data transfer rates and their technology is generally less expensive.

WAN (…………….. Area Network) spans

a ……………….. physical distance.

A WAN is a geographically-dispersed

collection of ………… The data transfer rate is

quiet …..………. . The ……………......... is the

largest WAN, spanning the Earth. WANs are

more susceptible to errors due to the

distances data travels. They are more

sophisticated and complex than LANs. Their

technology is expensive.

Networks may be class if ied according to a wide variety of characterist ics su ch as:

Scale , the medium used to transport the data , Topology, Communication protocols

used, Organizational scope, etc.



Metropolitan Area Network or shortened by MAN. A

network in a city with high-speed data transfer,

which connects various locations such as campuses, offices,

government, and so on. MAN network is a composite

of several LANs Coverage of this MAN among 10 to 50

km, MAN is the right network to build a network

between offices in the city of factories / establishments

and headquarters are within its range.

There are other computer networks like: Campus Area Network (CAN), Home Area

Network (HAN), personal area Network (PAN)…

The Data Transfer Rate (DTR) is the speed at which data can be transmitted between devices.

It’s often expressed in KB per second (KB/s) or MB/s. it depends on the distance, the quality of the line,

and the wire gauge.

Task 5: we want to make computers of the

following company to communicate and to

exchange data between them. How to do it?

…………………………………………………..

…………………………………………………..

Evaluation1: Deduce the differences between a LAN and a WAN? Complete the following table:

LAN WAN

Geographic area

Network cabling (means of

connectivity)

Data Transfer Rate (DTR)

Evaluation2: Give examples of LAN and WAN networks?

LAN WAN



B- Types of computer networks according to the main types of LAN architectures:

C- Network topologies: Types of computer networks according to their topology in a LAN Activity 6: Focus on these computer networks. What are the differences between them?

Observation: The difference between the three computer networks is in their ………….. : …………………………………………………………………………………………………

We talk about Network Topologies, so what does it mean?

Wireless Networks

The Wireless LAN provides wireless network communication over short distances using Wi-Fi, radio waves or infrared signals.

Or combined with :

Wired networks

The Wired LAN is a network using wires like cables to connect its components.



Activity 6: fill the blanks using these terms: nodes, the shape, Links, layout.

Activity 7: Try to search from the Internet the different kinds of network topologies.

There are many network topologies (used in LANs) such as:

………. topology: All devices are connected

to a ………………., called the ……. Bus

networks are relatively inexpensive and easy

to install for small networks.

……… topology: All devices are connected to

one another in the shape of a closed loop.

Ring topologies are relatively expensive and

…………….., but they offer …… data transfer

rate and can span ……… distances.

………….. topology: All devices are

connected to central equipment: …………Star

networks are relatively easy to install and

manage. All data must pass through the hub.

Tree Topology: integrate multiple star topologies

together onto a bus. In its simplest form, only hub

devices connect directly to the tree bus and each hub

functions as the "root" of a tree of devices. This

bus/star hybrid approach supports future expandability

of the network much better than a bus (limited in the

number of devices due to the broadcast traffic it

generates) or a star (limited by the number of hub

connection points) alone.

Network Topology refers to ................................, or the ...................... of a computer network. It determines how different ........................ and ....................... (Computer, printer, modem…) are connected to each other in a network and how they communicate.

http://en.wikipedia.org/wiki/Data_link

http://www.webopedia.com/TERM/T/device.html

http://www.webopedia.com/TERM/T/bus.html

http://www.webopedia.com/TERM/T/network.html

http://www.webopedia.com/TERM/T/ring_network.html

http://www.webopedia.com/TERM/T/star_network.html

http://www.webopedia.com/TERM/T/hub.html

http://www.webopedia.com/TERM/T/data.html

http://en.wikipedia.org/wiki/Computer_network

http://en.wikipedia.org/wiki/Computer_network



Evaluation3: Enumerate the advantages and the disadvantages of each network topology?

Bus topology Ring topology Star topology Tree Topology

Advantages

Disadvantages

II- LAN devices:

Computers

Network Interface Card

(Ethernet card)

Cables (cable RJ45)

Hub or switcher and router

Server (desktop computer)

Wireless NIC Wired NIC



Activity 8: Match each picture with its device’s description.

Device’s description Picture

a) Network Interface Card (NIC)

A NIC (pronounced 'nick') is also known as a network card.

It connects the computer to the cabling, which in turn

links all of the computers on the network together. Each

computer on a network must have a network card.

a+…

1)

b) Hub and Switch

A hub is a device used to connect a PC to the network. The function of a

hub is to direct information around the network, facilitating

communication between all connected devices. However in new

installations switches should be used instead of hubs as they are more

effective and provide better performance. A switch, which is often

termed a 'smart hub'.

Switches and hubs are technologies or ‘boxes’ to which computers,

printers, and other networking devices are connected. Switches are the

more recent technology and the accepted way of building today's

networks. With switching, each connection gets "dedicated bandwidth"

and can operate at full speed. In contrast, a hub shares bandwidth across

multiple connections such that activity from one PC or server can slow

down the effective speed of other connections on the hub.

b+…

2)

c) Network RouterA network router is quite

different from a switch or hub since its primary function is to

route data packets to other networks, instead of just the local

computers. A router is quite common to find in homes and

businesses since it allows your network to communicate with

other networks including the Internet. Essentially, a router

bridges the gap between other networks and gives your

network access to more features, e.g. afirewall, QoS, traffic

monitoring, VPN, and more.

c+……….

Activity 9: You have a folder that contains text documents, images and sound files. You want to give

a copy of this folder to your friends. Propose solutions to do it and comment it.

3)

http://www.computerhope.com/jargon/f/firewall.htm

http://www.computerhope.com/jargon/q/qos.htm

http://www.computerhope.com/jargon/v/vpn.htm



The local network is built to facilitate sharing hardware and software resources:

Sharing documents Sharing Printer Sharing messages Sharing screen

However, how we set up a Local Area Network?

Create a video to explain how, than share it with us.

1 How to Share Folders and Files in a Windows 7 Network Home Group: Homegroups in Windows 7 make it easy to share files, folders, music, pictures, videos, and printers with other people on your home network. After you have created or joined a Windows 7 homegroup, use these steps to share your folders and files with other computers connected to the homegroup.



2 How to Add a Shared Printer to a HomeGroup Network in Windows 7

Windows 7 is designed around networking. Consequently, Microsoft has designed it to be easy to add

a network printer to a HomeGroup network using Windows 7. And thanks to HomeGroup networking,

when you add a printer to a computer in the HomeGroup network, Windows automatically recognizes it

and adds it to the Device Stage on every computer in the HomeGroup.



With Windows 7, you can have both regular networks and HomeGroup networks. As long as a printer

(or other device) is attached to a computer within your network, you can add it to your HomeGroup,

even if the computer its attached to isn’t going to be part of the HomeGroup.

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1 3 Choose Start→Devices and Printers.

You see the Device Stage list. You may or may not have any printers indicated at this point.

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2 4 At the top, click the Add a Printer button.

Windows 7 asks whether you want to add a local printer or a network, wireless, or Bluetooth printer.

Enlarge

3 5 Click the Add a Network, Wireless, or Bluetooth Printer paragraph.

Windows starts searching for printers throughout your entire network. Usually, it finds the

printer you want. Sometimes it doesn’t. The wizard should show you a list of found printers.

http://media.wiley.com/Lux/34/147334.image0.jpg?h=400&w=535








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4 6 If you see your printer in the list, go to the next step. If Windows isn’t finding it,

click the Stop button and then click The Printer That I Want Isn’t Listed. Click the

Browse button and then locate the printer on your network.

If the wizard doesn’t display the printer you want to install, you can install it by typing its name into the Printer text

box under the Select a Shared Printer by Name option. The name should be in the form \\host\printer

Substitute for host the name of the printer’s host computer. Substitute forprinter the share name of the shared

printer (look on the host computer’s Printers list). The completed name should look something like

this:\\Dimension\LJ4.

5 7 Select the printer, click the OK button, and click the Next button.

Windows asks Do You Trust This Printer?

6 8 Click Install Driver. Then click Next.

Windows whirs and clanks for a while and then asks whether you want to make the new printer

your default printer.

7 9 Select the default printer and click Finish.

Your new printer appears in the Device Stage list. Notice that the Device Stage lists the type of printer

and tells you which computer it is attached to — in this case, Tamgaan (a Windows XP computer).

File and printer sharing has to be allowed on both the host computer and the computer the printer is

hooked into. To turn on file and printer sharing, choose Start→Control Panel and, under the Network

and Internet icon, click the Set Up File Sharing link.

How to Share Your PC’s Printer in Windows 7





Windows allows you to share a printer that is connected to your computer with other computers on your network

or within your workgroup. To share a printer attached to your Window 7 PC with other computers on the network,

follow these steps:

1. Open the Control Panel.

2. Choose the View Devices and Printers link found beneath the Hardware and Sound heading.

3. Right-click the printer icon.

4. Choose Printer Properties from the pop-up menu.

5. Click the Sharing tab.

6. Choose the option Share This Printer.

7. (Optional) Type a share name.

Be descriptive. The name Larry’s Color Laser is a good description, as is Mom’s Inkjet in the Den.

8. Click OK to share the printer.

Shared printers sport a tag on their icon in the Printers window. The icon looks like a man and a woman.

Some types of printers, such as PDF printers or Fax printers, cannot be shared on the network. Windows

bluntly tells you so when you make the attempt.

A shared printer is available only when the computer it's attached to is turned on.

You cannot print on a shared printer when the computer it’s attached to is in Sleep mode or Stand By mode.

Likewise, because Hibernation turns a computer off, you cannot use the printer attached to a hibernating PC.

You can print to any printer directly attached to the network, though that printer must be turned on as well.

The computers you share your printer with can be running any version of Windows, not just Windows 7.

Because you’re sharing one of the computer’s hardware resources and it affects all users on the computer,

you need administrator access to share the printer.

How to Enable File and Printer Sharing (Windows 7 and 8)

You can turn your humble Windows client computer running Windows 7 or Windows 8 into a server computer so that other

computers on your network can use your printer and any folders that you decide you want to share. In effect, your computer

functions as both a client and a server at the same time. A couple of examples show how:

It’s a client when you send a print job to a network printer or when you access a file stored on another server’s hard

drive.

It’s a server when someone else sends a print job to your printer or accesses a file stored on your computer’s hard drive.

Here are the steps to enable file and printer sharing in Windows 7:

1. Click the Start button, type Control Panel, and press Enter.

This step opens the Control Panel.



2. Double-click the Network and Sharing Center icon and then click Change Advanced Sharing Settings.

This step opens the Advanced Sharing Settings page, which lists network settings for each network you’re connected to.

a. For a home computer running Windows 7: Two networks are listed: Home or Work, and Public.

b. In Windows 8: The Home or Work network is called Private.

c. For a computer connected to a domain network: A third network named Domain is listed.

3. Click the down arrow next to the network you want to enable file and printer sharing for.

a. For a home computer: Click the down arrow next to Home or Work (Windows 7) or Private (Windows 8).

b. For a computer connected to a domain network: Click the down arrow next to Domain.

The figure shows the settings for a Domain network. The settings for a Home or Work network are the same.

Do not enable file or printer sharing for the Public network. Enabling file or printer sharing on a public network exposes

your computer’s data to other users on the same public network.

4. Select the Turn on File and Printer Sharing option.

5. Click the Save Changes button.

This action saves your changes and closes the Advanced Sharing Settings page.

6 Easy Screen-Sharing and Remote-Access Tools:

Here you go, free and easy-to-setup screen-sharing and remote-access tools. There are several ways you can benefit from

these apps: (1) Remote-Control: Help out your friend or mom with PC problems remotely, (2) Screen-Sharing: Collaborate on

running programs and documents with friends. (3) Remote-Access: Access your PC files from work, school, etc.

Screen-Sharing and Remote-Collaboration Apps 1. CrossLoop – secure, easy-to-setup, screen-sharing application for your Windows desktop.

Share your screen sessions with others.

http://www.crossloop.com/



Share/Collaborate on running programs (Word, Excel, Powerpoint, etc) with friends or colleagues.

File transfer and sharing.

Available in more than 20 languages.

CrossLoop Video intro:

https://www.youtube.com/watch?feature=player_embedded&v=F8xZ4nDmTTA

2. TeamViewer – slightly more complicated than Crossloop (not for dummies) but provides more or less

same capabilities. Remote desktop sharing, collaboration, file transfer, chat, etc. You (the sharer) can

decide whether you want to share the desktop or just allow the file transfer.

https://www.teamviewer.com

3. Yuuguu – little desktop application (Mac, Windows) that lets you (a) share your screen with others, (b)

collaborate on running programs with friends, and (c) access and control someone’s PC (friends, family, etc.) .

Yuuguu comes with in-built chat application that allows you to store and keep history of all Yuuguu conversations

online.

http://www.teamviewer.com/

http://www.yuuguu.com/



4. Unyte Lyte – Offers simple screen-sharing without any remote-control capability. Basically, the only thing

you can do with it is to invite someone and guide them through documents, websites, etc. On the other hand, it

can be integrated into your Skype client.

To Access your PC remotely

5. SoonR – access your PC remotely using your mobile or any other PC (work, school, etc.). Search files,

view/share documents (PowerPoint, Word docs, etc.), access email clients (Outlook, Mac Mail, etc.), run your

Skype client, and lots more right from your mobile or any web-enabled PC.

6. sVNC – “sVNC is a downloadable application that users who need support can easily install, so a Mac

guru (like you!) can help them out.“. Basically, it’s a program that enables you to provide remotes users with

access and control of your system. http://www.videolan.org/

7. PopMessenger

PopMessenger is a network-messaging program designed to chat and send messages over local network (LAN). The messenger can be used both as a multiple users chat and private-message exchange with offline messaging ability. To give the opportunity of delivering short messages to multiple individuals, the program provides you with a broadcast messages option that allows you to notify all users or a certain user group about different dates, events, etc. Moreover, it offers file exchange option so that you can easily send and receive different files from your friends. The messenger can log all your messages to the log folder you choose on your computer so that you could find and read them whenever you need. In the interface settings, you can determine text font and background color settings as well as set up sound alerts of incoming and outgoing messages, invitation to private chat, etc. This easy-to-use program allows you to stay in touch with your friends and colleagues and to get information of any kind quicker. It does not require an Internet connection as it works inside your local

network, which helps to considerably save your Internet traffic.

http://www.unyte.net/products/unyte.php

http://www.soonr.com/

http://svnc.sourceforge.net/



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Introducing Computer Networks and Loval Area Networks

Education

Transcript of Introducing Computer Networks and Loval Area Networks