INTRODUCTION

Data Processing, Information and Communication are three of the most important strategic issues for the success of every business or endeavour. We need information to do anything and most especially the right information, if we must be successful in our endeavours. 

In most cases information comes in bits and pieces called data. The data must be process, stored and converted into information be for it could be useful for communication.  

Today nearly all organization uses a significant number of computers and communication tools such are telephones, fax machines, personal handheld devices such as palm top, iPad, iPhone and mobile handsets. These tools for information processing and communication technology are often isolated from each other most especially the computers.  

While organizational managers today are able to use the newest applications, many departments still do not communicate and much needed information cannot be readily accessed. To overcome these obstacles in an effective usage of information technology, computer networks are necessary.

Computer networks can put down the barriers between information held on several other systems outside computers if they are networked. A border-less communication and information environment can only be built with the help of computer networks.

Computer networks allow the user to access local remote programs and remote databases either of the same organization or from other enterprises or public sources.

Computer networks provide communication possibilities faster than other facilities and provide optimal information and communication possibilities.

Besides these major reasons why any organization should not fail to have a computer network, there are other reasons as well:

1.      Cost reduction by sharing hard- and software resources

2.      High reliability by having multiple sources of supply of information.

3.      Cost reduction by downsizing to microcomputer-based networks instead of using mainframes.

4.      Greater flexibility because of possibility to connect devices from various vendors.

As a result of the importance of this technology, management of modern businesses that have not network their computers have a critical need for understanding the technology of computer networks, in other to benefit from the above reasons.

PART 1 

COMPUTER NETWORK

 1.         What Is A Computer Network

A computer network or data network is a telecommunications network which allows computers to exchange data.  A computer network is simply a collection of computers that are connected with wires, optical fibers, or wireless links so the various separate devices known as nodes can "talk" to one another and exchange data or computerized information.

In computer networks, networked computing devices exchange data with each other using a data link. The connections between nodes are established using either cable media or wireless media

2.       Why Network Computers

The primary reasons for networking computers are as follows:

1.       For easy sharing files and data.

2.    For sharing of resources or hardware devices such as printers, scanners, CD-ROM drives, hard drives and Internet connections. Without computer networks, device sharing is not possible.

3.    Communicate with other network users (e-mail, instant messaging, video-conferencing, etc.)

4.       Store data centrally (using a file server) for ease of access and back-up.

5.      Application sharing: Applications can be shared over the network, and this allows to implement client/server applications.

6.    User communication: Networks allow users to communicate using e-mail, newsgroups, and video conferencing etc.

7.      Network gaming: A lot of network games are available, which allow multi-users to play from different locations.

8.      Voice over IP (VoIP): Voice over Internet Protocol (IP) is a revolutionary change in telecommunication which allows to send telephone calls (voice data) using standard Internet Protocol.

3.       Types Of Computer Network

Basically there are four categories of networks:

1.       PAN (Personal Area Network)        

2.       LAN (local area network)

3.       MAN (metropolitan area network)

4.       WAN (wide area network)

Personal Area Network (PAN) is a home network of computers like laptops, desktop computers to a wireless router, printer, and other equipment in the house.  

Local Area Network (LAN) consists of a computer network at a single location, typically an individual office building. A LAN is very useful for sharing resources, such as data storage and printers. LANs can be built with relatively inexpensive hardware, such as hubs, network adapters and Ethernet cables. The computers are geographically close together that is, in the same building. If you work in an office, you probably use a LAN (Local Area Network), which is typically a few separate computers linked to one or two printers, a scanner, and maybe a single, shared connection to the Internet.

Metropolitan Area Networks (MAN), cover a whole town or city.

Wide-Area Networks (WAN) consists of computers that are farther apart and are connected by telephone lines or radio waves. Wide Area Networks cover a large geographical area. The Internet is a WAN that covers the entire world but, in practice, it's a network of networks as well as individual computers: many of the machines linked to the Net connect up through LANs operated by schools and businesses.

5.       Purpose of this Paper Presentation

The purpose of this paper presentation is to show how two computers can be networked without the use of HUB or Switch, in your home or office using Windows OS (Operation System) to share data.

PART 2 

ITEMS REQUIRED FOR THE NETWORKING A LAN

Items Required for the Networking a LAN

1.       Computers (Laptops, Desktops or Towertops) HUB or Switch or Router

2.       Ethernet Cable (CAT 5 or 6) of an appropriate length

3.       RJ–45 Plugs

4.       Cramping Tool

5.       LAN Tester

6.       Software to manage the network - Windows OS (XP, Vista, 7, 8 and 10)

1.       Computers (Laptops, Desktops or Towertops) HUB or Switch or Router

Talking about Local Area Network (LAN) in an office environment for example, generally you will need several computers, sometimes about 10 of them to be connected together for the purpose of networking. For the networking to be possible all the systems to be connected must have the Ethernet RJ-45 Port.  Ethernet RJ-45 Port could be located at the side of a Laptop and at the rear of a Desk or Towertop system unit. The pictures below shows the location of the Ethernet port in a Laptop, Desktop and Towertop Computers.  

Laptop, Desktop and Towertop Computers showing Ethernet Port

Ethernet is the name of the most commonly used LAN. A LAN (Local Area Network) is a network of computers that covers a small area like a room, an office, a building or a campus. Ethernet is a network protocol that controls how data is transmitted over a LAN. Technically it is referred to as the IEEE 802.3 protocol.

The protocol has evolved and improved over time and can now deliver at the speed of a gigabit per second. That's one million kbps.  The wired network in offices, at the banks, at home, hospitals, etc, is Ethernet LAN.

Most desktop, towertop and laptop computers come with Ethernet Card or Network Card integrated on the Mother Board inside the system unit so that it is ready to be connected to an Ethernet LAN through the Ethernet Port. Occasionally the Ethernet Card o the mother board can go bad. If it does, you card purchase an Ethernet or Network Card install it inside the system unit through the expansion slots provided at the back of the system unit. Below is the picture of an Ethernet Card.

  

Ethernet Card

Alternatively you can go for a USB Ethernet Card or Network Card, which you can plug into any of your USB Port of the Ethernet Card on the motherboard is not working. Below is the picture of USB Ethernet Port

USB Ethernet Port

2.      HUB, Switch and Router

To network a LAN, you need a HUB or Switch and a Router, depending on the size of the LAN.

There are three main devices that work to connect several computers to one another. A network Hub, Switch, and Router can all perform this function. Each device work differently and it is good to know how they work, for effective networking.

HUB

A network hub is designed to connect computers to each other having connecting ports just like a switch but with no real understanding of what it is transferring, meaning it is not an intelligence device. A network hub is used for a private network, one that does not have any connections to sources other than local computers meaning, no Internet access.

 

HUB Connected To Four Computers

How a HUB Works

When a hub receives a packet of data from a connected device, it broadcasts that data packet to all other connected devices regardless of which one data packet is intended for. For example if a data packet is transmitted from Computer A on the HUB intended for Computer D the data packet will be sent to all the other computer B and C connected to the HUB.

Disadvantage of HUB

Additionally, network bandwidth is split between all of the connected computers. So, the more computers that are connected, the less bandwidth that is available for each computer, which means slower connection speeds.

Network Switch

Network Switch is also used to connect computers to each other, like a HUB. The Switch differs from a HUB in the way it handles packets of data. When a switch receives a packet of data, it determines what computer or device the packet is intended for and sends it to that computer only.

 

Network Switch Connected To Four Computers

How a Switch works

For example if a data packet is transmitted from Computer A on a Switch, intended for Computer D the data packet will be sent to D directly.  This makes a Switch intelligent.

Advantage of a Switch

It does not broadcast the data packet to all computers as a HUB does which means bandwidth is not shared and makes the network much more efficient. Switches knows the location addresses of the devices that they are connected to almost instantaneously. The result is that most network traffic only goes where it needs to rather than to every port like the HUB. On busy networks, this can make the network significantly faster.

Network Router

A 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.

 

Two Network Connected with a Router

  

 A router is quite common to find in homes and businesses since it allows your network to communicate with other networks including the Internet. Basically, a router is used to connect other networks like the Internet and gives your network access to more features.  As far as simple traffic routing is concerned, a router operates exactly as a switch, knowing the IP addresses of the computers on its connections and routing traffic only to those computers.

3.      Ethernet or Network Cable (CAT 5, 5e or 6)

Category 5 Cable, commonly referred to as Cat 5, is an Unshielded Twisted Pair (UTP) cable used for carrying signals. This type of cable is used for computer networks such as Ethernet. It can handle 10/100 Mbps speeds (Fast Ethernet) at up to 100 MHz bandwidth is suitable for most varieties of Ethernet over twisted pair. Cat 5 is also used to carry other signals such as telephony and video.  Category 5 was superseded by the Category 5e specification, and later category 6 cable.

 

Used for computer Network, this cable is commonly connected to Ethernet Plug using 8P8C (8 position 8 contact) modular connectors which often referred to as RJ45 Connector. Below are pictures of two drums of Cat 5 Cable in blue and grey colour.

 

Cat 5 Network Cable

Category 5 Cable Standard

The standard for category 5 cable is defined in ANSI/TIA/EIA-568-A. ANSI/TIA-568 is a set of telecommunications standards from the Telecommunications Industry Association (TIA). The standards address commercial building cabling for telecommunications products and services.

The cable is terminated in either the ANSI/TIA-568-A scheme or the ANSI/TIA-568-B scheme, which are often referred to as the T-568A scheme and T-568B scheme, which has to do with the colour arrangement of the cables. The two schemes work equally well and may be mixed in an installation so long as the same scheme is used on both ends of each cable.

Colour Specification for Cat 5 Ethernet Cable

Cat 5 Cable comes in eight strands of four different pairs of cables of different colour arrangement.  The picture and diagram shows the colour code of Cat 5 UTP Cable.