Computer Network Assignment A134183 & A134389

This assignment has been introduced to students of Faculty Information and Science Technology to see how the students can learn and gain knowledge through this wiki project. As we know, wiki has been widely used by the students to do research and gain some info to complete assignments that had been given by the lecturers. Apart from that, wiki helped a lot because it has reference part which is brings you directly to some relevence sources.

Background
A Computer Network. What is a Computer Network?

A computer network is a collection of computers and devices which is two or more, connected together via communications devices and transmission media. This allow users to communicate and share resources among each other. In the 1960s, the Advanced Research Projects Agency (ARPA) started funding the design of the Advanced Research Projects Agency Network (ARPANET) for the United States Department of Defense. It was the first computer network in the world. Development of the network began in 1969, based on designs developed during the 1960s.

Benefits
Many advantages or benefits can be obtain from the Computer Network. The following are the advantages of Computer Network:
 * Facilitating communications - by using Computer Network, people communicate efficiently and easily via e-mail, instant messaging, chat rooms and etc.
 * Sharing hardware - In a networked environment, each computer on the network has access to hardware on the network. this allow users to save money which is, sometimes a hardly can be too costly.
 * Sharing data and information - any authorised computer users can access data and information stored on other computer in the network. A large company, for example have a database of customers information which is, any authorised person or users of a smart phone can access to the database.


 * Sharing software - users on the network have the access to the software. To support multiple user's access of software most vendors sell network version or site licenses of their software which usually cost less tahn buying individual copies of the software. A network license is a legal agreement.
 * Transfering funds - also called as electronic funds transfer (EFT) which allows users connected to a network and transfer money from one bank account to another via transmission media.

What is Network Classification
There are two type of transmission technology: Broadcast networks have a single communication channel that is shared by all the machines on the network. Short messages, called packets in certain contexts, sent by any machine are received by all the other. An address field with the packet specifies for whom it is intended. Upon receiving a packet is intended for itself, it processes the packet; if the packet is intended for some other machine, it is just ignore.
 * broadcast,
 * point-to-point (peer-to-peer).

As an analogy, consider someone standing at the end of a corridor with many rooms off it and shouting.

Although the packet may actually be received (heard) by many people, only Watson responds. The other just ignore it. Another example is an airport announcement asking all flight 444 passengers to report to gate 10.

Broadcast systems generally also allow the possibility of addressing a packet to all destinations by using a special code in the address field. When a packet with his code is transmitted, it is received and processed by every machine on the network. This mode of operation is called broadcasting. Some broadcast system also support transmission to a subset of the machines, something known as multicasting. one possible scheme is to reserve on e bit to indicate multicasting. the remaining n-1 address bits hold a group number. Each machine can "subscribe" to any or all the the groups. When a packet is sent to a certain group, it is delivered to all machines subscribing to that group.

On the other hand, point-to-point (peer-to-peer) networks consist of many connections between individual pairs of machines. To go fro the source to the destination, a packet on this type of network may have to first visit one or more intermediate machines. Often multiple routes, of different lengths are possible, so routing algorithms play an important role in point-to-point networks. As a general rule (although there are many exception), smaller, geographically localized networks tend to use broadcasting, whereas larger networks usually are point-to-point

Two Types of Network based on Physical Scope
There are many types of network based on physical scope. The two most common types of network are as follows:
 * Local Area Network - A local area network which is also known as LAN is a network that connects computers and devices in a limited geographical area such as home, school, computer laboratory, office building, or closely positioned group of buildings. Each computer or device on the network is a node, often shares resources such as printers, large hard disks and programs. Often the nodes are connected via cables.
 * Metropolitan Area Network - A metropolitan area network which is called as MAN is a high speed network that connects local area networks in a metropolitan area such as a city or town and handles the bulk of communications activity across that region. A MAN typically includes one or more LAN's but covers a smaller geographic area than wide area network (WAN). A MAN usually is managed by consortium of users or by a single network providerthat sells the service to the users. Local and state government, for example regulate some MANs. Telephone companies, cable television operators and other organisation provide users with connection to the MAN.

Basic Hardware Components
Network cards

A network card which is also called as network interface card (NIC) is a piece of computers hardware taht enables a computer or device taht does not have built-in-networking capability to access a network. The network cards coordinates the transmission and receipt data, instructions and information to and from the computer or device containing the network card.

Reference
Shelly,Gary B. and Vermaat,Misty E. "Discovering Computers 2010, Living in a Digital World", 2010 Edition