Chpt17a Networking Fundamental

8/9/2019 Chpt17a Networking Fundamental

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Chapter 17Networking Fundamental


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Slide 2Chapter 17 Networking FundamentalVer 1.0 10 April 2001

Network

What is a Network?2 or more computers connected toshare data

What are the 3 components ofNetwork?1. Protocol

2. Transmission Media3. Network Services (Shared

Resources)

What are the objectives of Network?Sharing of files, peripherals, storageand software. Data transfer is fast.

What types of Network are there?LAN (Local Area Network)WAN (Wide Area Network)

How do you define a LAN?Network within a site eg a building

How do you define a WAN?

Network of LAN over a largegeographic area.

Comparing LAN and WAN, which hasfaster transfer speed?

LAN

LAN

WAN


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Types of LAN

What are the Types of LAN?1. Peer-to-Peer2. Server-based

What are the characteristics of Peer-to-Peer?1. Workstation can both function as

Server and client2. Each PC can share its resources eg

printer, files (Server)3. Each PC can use other PC resources

(Client)4. Management of PC is local (by the

user)

5. Not very secure

In what situations are Peer-to-peersuitable?1. 10 to 20 workstations2. Security is not very important

What are the operating systemssupporting Peer-to-Peer network?

1. Windows 3.1

2. Windows 95

3. Windows 98

4. Windows NT Workstation

5. Windows 2000 Professional6. Windows 2000 Server

What is Peer-to-Peer Network alsoknow as?

Workgroup

Peer-to-PeerNetwork


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Types of LAN

What are the characteristics ofServer-Based Network?

1. Centralised server to manage allfile, printer, and application sharing

2. A System Administrator managesthe network resources eg useraccess

3. More secure

In what situations are Server-basedsuitable?

1. Many users

2. Need to manage access to network

resources3. Security is very important

What are the operating systemssupporting Peer-to-Peer network?

1. Windows NT Server

2. Windows 2000 Server


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Network Topologies

What is Topology?Physical layout and logical organisationof a LAN.

What is Physical Topology?

How network are actually connected

What is Logical Topology?

Actual path that the signal travels overthe network

What are the 3 types of LAN

Topologies?1. Bus

2. Ring

3. Star

4. Mesh

What is a Bus?Every PCs are connected to a sharedcable or backbone. Terminatingresistors are attached to both end ofthe cable. Simple and low cost.

Bus Topology

Terminating Resistor Terminating Resistor


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Network Topologies

What is a Ring?Clients and Server form a loop. Ring isimplemented as Logical Star, where allclients are connected to a hub.

What is a Star?All clients radiate from a central hub.Reliable as a failed client will not affectother computers. Larger the network,higher the cabling cost.

What is Mesh?

Every PC is connected to other PCs.Most reliable but very costly.

Ring Topology

Star Topology

Mesh Tologogy


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LAN Protocols

What is the function of Protocol innetwork?

Provide a common language for PC tocommunicate

What are the 2 common LAN protocols?

Ethernet and Token Ring

What is Ethernet?

Introduced by Xerox. Use CSMA/CD toensure data is sent safely from 1 PC toanother in the shared media.

What is CSMA/CD?

Carrier send multiple access/collisiondetection.

How CSMA/CD works?The shared media (BUS topology) mustbe cleared before a PC can sent itsdata. If more than 1 PC put its data onthe media, there is a collision. Data aredestroyed. All PCs all then hold backand try again at different random time.

What is Token Ring?Introduced by IBM. It uses acirculating Token to grant a PC theright to transmit data. Every PC has anequal chance to transmit data.

How Token Ring works?Any PC that want to transmit data willwait for the Token to arrive. It thentakes the Token, mark it as busy, sendthe data and release the Token (free)for next PC.


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Cable

What do the Number 10 or 100 means?Transmission speed. 10 for 10Mbps

What does the Base means?Baseband

What does the T in 10BaseT means?Twisted Pair

What does the FL in 10BaseFL means?Fiber Optics cable

Cable Description Max Length

10Base5 Use as backbone, 15-pin D-shapedconnector (AUI) and transmit at 10Mbps

500m

10base2 (Thinnet) Speed = 10Mbps, Use BNC connector 185m

10BaseT Unshielded twisted pair (UTP)

Cat 3, 4, and 5 ,RJ45 connector

Speed = 10Mbps

100m

100BaseT Cat 5 UTP , RJ45 connector

Speed = 100Mbps

100m

10BaseFL/100BaseFL Optic-Fiber cable, 10Mbps or 100Mbps 2Km


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Networking Interface Card

What is also commonly known as?NIC

What is the purpose of the NIC?

Links the Computer to the Network.Serve as input or output device,transferring data in and out of thecomputer.

What types of NIC is available?

1. Server NIC

2. Standard NIC

How difference is the Server NIC?

Has own processor and RAM to processgreat amount of data flowing throughthem.

BNC

DB15

RJ45


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Other Networking Devices

What are the other network devices?1. Repeater

2. Hub

3. Bridge

4. Router

5. Switch

6. Gateway

What is a Repeater?

Amplify signal to prevent degradationof signal when it travel over longdistance. Used to extend the network

beyond the cable specifications

What is a Hub?

Central connection point connecting PCsin a Star topology

Repeater

Hub


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What is a Bridge?Network is often split into smallersegment to reduce data traffic. Bridgeis used to connect 2 or more segmentinto 1 logical network. PC from 1segment can communicate with anotherPC from another segment.

What is a Router?

Redirect data traffic using IP address.It can determine the best path toredirect the data in a network.

Bridges

Network Segment

Network Segment

Network A

Network BNetwork CRouter


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What is a Switch?Direct information flow on a networkfrom 1 PC to another. Function like ahub, but must faster by providingdedicate path between 2 PCs.

What is a Gateway?

Device or Computer than connectsnetwork that uses different protocols(language). It transfers and translatesdata for use by either network.

Network

Server

Internet

Gateway

The Internet


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Checking/Installing Network Protocols

Where to check Installed Protocols inWindows 9x?

Control Panel, Network applet

Where to check Install Protocols inWindows 2000?

Control Panel, Network applet, LocalArea Connection

How to add a Network Protocol inWin9x?

1. Control Panel, Network applet

2. Add, Protocols

Eg to install NetBeui protocol:click Microsoft, Click NetBeui

How to add a Network Protocol inWin92000?

1. Control Panel, Network applet

2. Right-click Local Area Connection

3. Properties

4. Install

5. Add

(Windows 9x)


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InterNetwork Protocols

What is network Protocols?Agreed rules for transmitting databetween two devices

What are the common Protocols?

1. IPX/SPX

Use in Novel Network2. NetBEUI

Use in Microsoft Network

3. TCP/IP

Default protocol used in theInternet.

4. AppleTalk Use in Apple Network

5. PPP (Point-to-Point)

Use to connect computer tothe Internet

6. SMTP (small mail transfer protocol) Protocol to sent emails between

servers

7. POP (post office protocol)

Protocol use by client to receiveemails

8. HTML

Authoring language to createdocument on the Web

9. FTP

Use to send files through theInternet


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Internet: TCP/IP

What is TCP/IP?Transmission control protocol/Internetprotocol

What is its function?

Handles the delivery of data in theinternet

What is IP?

Unique logical address used to identifyeach clients connected to the Network,eg 143.10.4.122.

What are the format used in IP?

Either Dotted Decimal (above example)or in Binary,

11111111.11111111.11111111.11111111

What does IP comprises?A Network ID and a Client ID. TheClient ID identifies the PC in theNetwork.

What are the classes of IP?Class A : 1 126 (255.0.0.0)

Class B : 128 191 (255.255.0.0)Class C : 192 223 (255.255.255.0)Class D : 224 239Class E : 240 -255

How can you identify the Network IDfrom the Client ID?Use Subnet Mask eg 255.255.255.0Eg 10.128.12.1 with subnet mask255.0.0.0. Network ID is 10 and ClientID is 128.12.1


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Troubleshooting TCP/IP

What are the tools used to check/determine IP problems?

1. WINCFG (Win9x only)

2. IPCONFIG

3. PING

4. TRACERT

How to activate these commands?

1. Start, Run, Command

2. Type the utility name eg IPCONFIG

What can be done with WINCFG?

Release and Renew IP

How to show all information withWINCFG?

WINCFG /ALL

What can be done with IPCONFIG?1. Check IP address

/ALL

2. Release IP address

/RELEASE or /RELEASE_ALLfor Win9x

3. Renew IP address /RENEW or /RENEW_ALL forWin9x

What is the use of PING?

Check connection eg PING WWW.SG

What is the use of TRACERT?

List the paths taken by the IP to reachdestination. Able to find out the pointof connection failure.


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Network Services

What are the 2 Network Servicesrequired in Network?

DHCP

WINS

What is DHCP?

Dynamic Host Configuration Protocol

What is the function of DHCP?

A protocol for assigning dynamic IPaddresses to devices on a network.With dynamic addressing, a device canhave a different IP address every timeit connects to the network.

What is a DHCP server?A server that provide IP addresswhenever a client PC request it.

What is WINS?WINS is a Microsoft NetBIOS nameserver (NBNS)

What is the purpose?WINS eliminates the need for a clientto broadcasts to find the computernames it want to communicate usingknown IP addresses. Improve networkperformance.

DHCP ServerClient

Request for IP address Provide IP address


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Internet Connection Sharing

What is Internet Connection Sharing?

Allows 1 PC to share its internetconnection with other PCs

What are the Microsoft OperatingSystems that support ICS?

Windows 98 Second Edition

Windows ME

Windows 2000

How to install ICS in Windows 9x?

Install the ICS via Control Panel,

Add/Remove Program, Windows Setup,Internet Tools

How to install ICS in Windows 2000?

1. My Network Places,

2. Properties of 1 exiting connection

3. Sharing and enable ICS

Host PC withICS installed

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