Comput3r N3tworks

Hi, everyone! Time passes so fast that here comes the fourth lesson of us with our lecturer, Dr.Dayang. Today we learn about 'Computer Networks'. After the lesson today, I gain some extra knowledge on networking, for example types of LAN used, definition of server, the differences of the four transmission media (Router, Gateways, Bridges and Hub). Besides, my coursemates have put pretty much effort on presenting the application of E-mail to us which is very informative and systematic. I really learn a lot and this is the first time I am exposed to the software named 'Thurderbird' that is very useful fo rme to check my e-mail even I am offline.

Below are the summarize of mine for today's lesson:

What is networking?

• Networking is a collection of computer and other hardware devices that are connected together to share hardware, software and data as well as to communicate of one another.

What is server?

• Server is to store all software that controls the network and to share by all the computers attached to the network. 

How many types of network classification?

• Network used based on geographic coverage.
• Basically have four types of Network: LAN (Local Area Network), WAN(Wide Area Network), MAN( Metropolitan Network) and PAN(Personal Area Network).

LAN

• restricted to relatively small area. e.g. lab, school or building
• rarely more than a mile apart.
• typical LAN configuration: 1 computer = a server
• cable are used to connect the network (cable can be bound and unbound)

WAN

• connect larger area such as JB Malaysia, World Cable or satellite uplinks used to connect this type.
• is complicated.
• using multiplexing to connect local and metropolitan network : hybrid network.

MAN

• usually spans a big/large campus.

PAN

• computer network organized around an individual person.

How are networks categorized?
 based on 3 properties: -

• Topology      : geometric arrangement of the network
• Protocol       : common set of rules and signals the communication on the network use to          communicate
• Architecture : peer to peer / client / server

How many types of transmission media?
2 types:-

• bounded media (with cable) and unounded media (wireless)
• bounded media e.g. twisted pair wire, co-axial cable, fiber optic cables
• unbounded media e.g. AM and FM radio, TV broadcasting, satellite communication, microwave radio, infrared signals.
•  e.g. Router, Gateways, Bridges and Hub.

Router

• Devices which connect two or more networks that use similar protocol.
• Operates at a network layer of O.S.I model
• Data is grouped into packets / block of data. Network address allows routers to calculate more accurately and efficiently the path of the computer.

Router

Gateways
• Devices which connect two or more networks that are different protocols.
• Operate at all seven layer of O.S.I model.
• Perform data conversion that is why slower in speed and expensive devices.

Gateways

Bridges

• Used to connect similar network segments
• Bridges work at the data link layer of O.S.I model.
• Bridge possesses infomation about the data they receive with slow performance.

Bridge

 Hub ( 4 types of Hubs : Passive Hub, Active Hub and Switch/Intelligent Hub)

• Are basically multiports repeaters for U.T.P. cables.
• Hubs have ports for other type of cable such as coaxial cable.
• Range on size for 4 ports and specific to the network type.

Hub

That's all from me.. Thank you for reading:)