AHSANULLAH UNIVERSITY OF SCIENCE & TECHNOLOGY

2012

Introduction to Computer in Business

(Course: 215) Assignment on: Network System: A case study

on Ahsanullah University of Science &

Technology

School of Business

1 4 1 - 1 4 2 L O V E R O A D , T E J G A O N I N D U S T R I A L A R E A , D H A K A 1 2 0 8

INTRODUCTION

NETWORK:

A Network is a set of technologies including hardware, software & media that can be used to

connect computers together. It enables them to communicate, exchange information & share

resources in real time. Network open up new ways to communicate, such as e-mail & instant

messaging (IM).

By allowing users to share expensive hardware resources such as printer, network reduce the cost

of running an organization.

TYPES OF NETWORKS:

Network can be classified in two ways:

1. Common types of Network: It includes:

Local Area Network (LAN)

Wide Area Network (WAN)

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2. Hybrid Network: It includes:

Campus Area Network (CAM)

Metropolitan Area Network (MAN)

Home Area Network (HAM)

Network Topology:

The logical Layout of the cables & devices that connect the nodes of the network is called

Topology. The kind of topology or combinations of topologies to use depends on:

a. The type of computers & cabling in place

b. The distance between computers

c. The speed at which the data must travel around the

network

d. The cost of setting up the network

The Types of Network Topology:

Different types of topologies are as follows:

Bus Topology

Star Topology

Ring Topology

Mesh Topology

Bus Topology: Network use one cable, all the nodes & peripheral devices are connected in a

series to that cable.

Star Topology: All the nodes are connected to a hub or switch & communicate through it.

Ring Topology: Connects the network’s nodes in a circular chain, with each node connected to

the next. The last node connects to the first completing the ring.

Mesh Topology: A cable runs from every computer to every other computer.

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Networking History in Ahsanullah university of Science & Technology

(AUST):

At AUST there is internet & Wi-Fi connection. The Internet Connection was connected in June-

July, 2008. The Internet Service Provider (ISP) is Metronate Bangladesh Ltd. The Wi-Fi

connection was connected in December, 2010. It is connected by Banglalion. The band width

speed of the Internet is normally 100 kbps.

Department wise Networking System in AUST:

There are 7 departments. All the departments have total 10 computer labs which are connected

to a router through star topology. Most of the PC is connected to the Internet. They are connected

Through Local Area Network (LAN). The basic connecting system is as below:

Figure: Internal Networking System in a Lab

The features of the computer labs of AUST are as follows:

School of Business Department:

There are total 40 PCs.

They are connected through Local Area Network

(LAN)

Operating System: Windows XP

Service Pac -2

Software: Microsoft Office 2007, SPSS, Turbo –C

for using C++

1 piece Pentium 4 & the rest are XP

Monitor: Samsung

Server Switch Blue Cable/

Internet Cable PC

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Department of Textile Technology:

There are total 31 PCs

Operating System: Windows XP

Link+ Internet

Printer Connected

1 PC has Core-1,rest of the PCs have Dual Core

Software: Programming, Graphics, Textile related

software

Speed: 60-100 kbps

Department of Electrical & electronic Engineering:

Having 3 Computer Lab

Total 38 PCs, 10 have Internet connection, all are

running

Speed: 60-100 kbps

Monitor: Model-CRT

O.S: Windows XP

Service Pac- 2,3, license key & without license key

Core 2, Dual Core

Software: C++, Met lab, Or cad, Micro-wild, Silos,

DHCH-2

Department of Computer Science & Engineering:

Windows XP

Having Internet connection

Linux

Software: S- 27

Besides the core network & Internet Service System of the university are also maintained under

the guidance of the department, & the major servers are located at the “University Server

Room”.

Department of Civil Engineering:

Having Computer Aided Design & Drafting Lab

Monitor: 26 are IBM, rest are ACO

O.S: Windows XP

Having 34 PCs, all have internet connection

4 PC have Dual Core, 26 have Pentium -4

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Software: Auto-cad, E- tabs, Microsoft 2007

6 PCs have Service Pac- 2, rest have Service Pac -3

Speed: 10-20 kbps

Ram: 4 PC have 2 GB, 25 have 512 GB, 1 has 1GB

Hard-disk: 26 PC have 80 GB, 8 PC have 300 GB

Department of Architecture:

Having 1 Computer Lab, 30 PCs

O.S: Windows XP, Microsoft 2007

4 PCs have internet connection

Software: Auto-cad, Sketch-up

4 PCs have Core 2

Network Media:

Network media refers to the means used to link a network’s node together.

Types of Network Media: Network media is of two kinds:

1. Wire-Based Media

a. Twisted pair cable

b. Coaxial cable

c. Fiber optic cable

2. Wireless Media

a. Radio signal

At AUST there is both the wire-based & wire-less network media. They basically use “UTP cable” &

“Fiber optic cable”.

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UTP Cable: UTP is Unshielded Twisted Pair loom. It can flow data in a distance of 100 meters

authentically. If the distance is more than 100 meters then intermediary devices can be used. Maximum 3

intermediary devices can be in this regard. The market value of UTP cable is TK.30-35 per meter.

Image: UTP Cable

Fiber Optic Cable: The inner part of this cable is of glass-core. There is gel which protects the inner part

& helps to avoid hard-crack. It is expensive. The market value of Fiber Optic Cable is Tk. 200-250 per

meter.

Image: Fiber Optic Cable

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Network Hardware: All data moves between PCs, it needs to be channeled properly to

reach its final destination. To make this possible, the proper hardware must be attached to &

between all PCs.

Types of network Hardware:

1. Network Interface Cards (NICs): Hardware

components to control the flow of data.

2. Network linking Devices: Interconnect at least two

computers. It includes Hubs, Bridges, and Switches & Routers.

3. Cabling Equipment: It is designed to work with a

certain kind of network topology & each one has certain standard feature. It includes

Ethernet, fast Ethernet, Gigabit Ethernet, and Token Ring.

Switch

Definition: A network switch is a small hardware device that joins multiple computers

together within one local area network (LAN). Technically, network switches operate at layer

two (Data Link Layer) of the OSI model.

Network switches appear nearly identical to network hubs, but a switch generally contains more

intelligence (and a slightly higher price tag) than a hub. Unlike hubs, network switches are

capable of inspecting data packets as they are received, determining the source and destination

device of each packet, and forwarding them appropriately. By delivering messages only to the

connected device intended, a network switch conserves network bandwidth and offers generally

better performance than a hub.

Image: Switch (Front Side) Image: Switch (Back Side)

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Image: Connected Switch

Router

Definition: Routers are physical devices that join multiple wired or wireless networks

together. Technically, a wired or wireless router is a Layer 3 gateway, meaning that the

wired/wireless router connects networks (as gateways do), and that the router operates at the

network layer of the OSI model.

Home networkers often use an Internet Protocol (IP) wired or wireless router, IP being the most

common OSI network layer protocol. An IP router such as a DSL or cable modem broadband

router joins the home's local area network (LAN) to the wide-area network (WAN) of the

Internet.

By maintaining configuration information in a piece of storage called the routing table, wired or

wireless routers also have the ability to filter traffic, either incoming or outgoing, based on the IP

addresses of senders and receivers. Some routers allow the home networker to update the routing

table from a Web browser interface. Broadband routers combine the functions of a router with

those of a network switch and a firewall in a single unit.

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Image: Router (Front Side) Image: Router (Back Side)

Node

Definition: A node is any device connected to a computer network. Nodes can be computers,

personal digital assistants (PDAs), cell phones, or various other network appliances. On an IP

network, a node is any device with an IP address.

Total Networking System in AUST:

In AUST there are two types of connectivity, wire-based connectivity & wire-less connectivity.

In wire-based connectivity the Server is connected through “Fiber Optic Cable” to the Router.

“The Router” is a Networking device. It is used to connect two or more than PCs. There are

many ports in a Router. One port is connected to the “Mail Server” & another one is connected

to the “Proxy Server”.

Proxy Server:

All the PCs of the University are connected to the Proxy Server. This Proxy Server is configured

in a way that it can do multiple works.

It works as Proxy server/ Squid Server

It works as Dynamic Host Configuration Protocol (DHCP) Server

It works as Bandwidth Controller (Squint)

It works as MRTG, Bandwidth usage

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The Proxy Server is Linux Based Server. This Proxy Server can allocate net facility for a specific

time in different Laboratories. The speed of the Switch is 100 mbps in LAN Bandwidth. If

anybody searches for any websites which was searched before on that day then the proxy server

would provide it from its cash-memory. In case of downloading huge page it would be faster.

The DHCP is in configured in AUST Server. There are so many PCs in AUST. Every PC has a

unique IP address. To get unique IP address “Obtained IP Address Automatically” must be

selected. Then every PC would be identified uniquely. There would be no conflict, no

overlapping.

The Bandwidth Controller supplies 4 mbps. It controls how much mbps would get each

department. It can assign bandwidth. In this case Linux –Based Package Software is used. It can

be monitored from the server that which PC gets how much mbps.

The MRGT is updated in every 5 minutes. It shows graphically that if they get the required mbps

that is 4 mbps. It can be shown on day basis or monthly basis.

Mail Server:

The Mail Server is used by the teachers or employees of the University. They use this Server by logging

in mail.aust.edu. They have unique IP address through which they can send/transfer mail.

Networking:

The Proxy Server is connected to a Switch through the “UTP Cable”. There is a limitation to transfer data

through UTP Cable. It can transfer data to a maximum distance of 100 meters without any loss. If the

distance is more than 100 meters then data missing is occurred.

As a result, when the distance is more than 100 meters they use “Fiber Optic Cable” to transfer data. In

AUST Building there is 4 Blocks (Block A, Block B, Block C & Block D). These Block have a distance

more than 100 meters. So, there is 4 Manageable “Fiber Switch”. Each Fiber Switch is situated in the

middle position of the building. As for example in level 3, EEE department there is a Fiber Switch in the

central position. The Fiber Switch is connected by Fiber Optic Cable as the distance is above 100 meters.

All the PCs of Block A is connected to the Fiber Switch of Block A & so on.

The Server is used to distribute proper internet service to all the students & if there is any need to control

anything.

The AUST has Caspersky Anti-virus Server. The Server based Anti-virus is used in different computer

labs.

AUST’s Server is hosted in USA. The main server is there. From here, they can up-load, customize etc.

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Wi-Fi Network:

In AUST there is Wi-Fi connection. It is completely detached from wire connectivity. The connectivity is

received by Banglalion Outdoor Unit. It is, as described before, connected to the Proxy Server, then

Switch, then wire-less Router. It can be monitored by proxy server also. The Wi-Fi network is connected

in Ground Floor & level-1.

Image: Wi-Fi Wireless

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Image: Wi-Fi & Internet Network

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The Network System in AUST can be shown in flow-chart:

UTP Cable

Fiber Cable UTP Cable Fiber Cable

Fiber Cable Fiber Cable

UTP Cable

Figure: Network System

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ISP

Router

Mail

Server

Proxy

Server

Manageable Fiber+

UTP Switch

Manageable Fiber

Switch

Fiber Switch

(Block-C)

Fiber Switch

(Block-D)

Fiber Switch

(Block-A)

Fiber Switch

(Block-B)

PC 1 PC 2

Switch/ hub

Kaspersky Anti-

virus Server

The Wi-Fi Zone of AUST is shown in the following flow-chart:

UTP Cable

Figure: Wi-Fi Network

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Banglalion

Outdoor Unit

Proxy

Server

Switch

Wireless

Router

Wireless

Router

Wireless

Router

Wireless

Router

PC PC PC PC

CONCLUSION

From this survey & assignment we can see how a Network System is connected in an

Organization. I have learnt how it works, also learnt the structure of the Network System. In the

Network System the most common factor is to connect the switches/routers/devices in a proper

way with a cost-effective media. The UTP Cable plays the most important role in this regard. As

it is less expensive than Fiber Optic Cable. A proper Network System can go along run in

management of an organization.

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REFERENCE

Introduction to Computer by Norton

Computer Labs of AUST

Lab Assistants of AUST

System Engineer of AUST

Different Books/websites

www.about.com

www.buzz.off.com

www.dictionary.com

Images from AUST Computer Lab, Server Room &websites

www.answer.com

Thank You