Network+Hardware

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 * ** Component ** ||  ** What does it do? **  ||  ** Image **
 * File Server || A file server is a computer attached to a network that has the primary purpose of providing a location for shared disk access. This is for shared storage of computer files (such as documents, sound files, photographs, movies, images, database, etc.). || [[image:http://mnyiko.wikispaces.com/site/embedthumbnail/placeholder?w=200&h=147 width="200" height="147" align="left"]] ||
 * Network Interface Card || Network cards are needed if the computer does not have a built-in network chips on the motherboard. They allow the signal from the network to be transmitted to the machine – this could be a fixed cable, infrared or radio waves. || [[image:http://mnyiko.wikispaces.com/site/embedthumbnail/placeholder?w=200&h=93 width="200" height="93" align="left"]] ||
 * Network Cables || Network cables are used to connect one network device to other or to connect two or more computers. || [[image:http://mnyiko.wikispaces.com/site/embedthumbnail/placeholder?w=200&h=97 width="200" height="97"]] ||
 * Hub || A hub is a hardware device that connects multiple computers together in a network and allows them to share data packets.

Each computer will be connected to a single ‘port’ on the hub. So if you purchase an ‘8 port hub’, you will be able to connect up to eight computers. || ||
 * Router || A router is a device that transfers data from one network to another in an intelligent way. It has the task of forwarding data packets to their destination by the most efficient route.

In order to do this, the router has a micro computer inside it. This holds a table in memory that contains a list of all the networks it is connected to, along with the latest information on how busy each path in the network is, at the moment. This is called the ‘routing table’. || ||
 * Switch || A network cable can only have one data packet in it at any instant.

So if two or more computers want to place a data packet on to the network at exactly the same time, then a ‘ data collision’ will take place.

The network protocol is set up to deal with this. Basically it declares the collided data as unusable and forces the two computers to re-send their data packets at a slightly different time.

This is fine for a lightly loaded network with only a few computers on-line. You will not notice the small delay caused by data collisions. || ||
 * Modem || A modem converts the digital data from the computer into a continuous analogue wave-form that the telephone system is designed to deal with (MODulation). The reason for this is that the telephone system was originally designed for the human voice i.e. continuous signals. The modem also converts the analogue signal from the telephone network back into digital data that the computer can understand. (DEModulation). Hence the word MODEM.

Standard ADSL modems come in two forms. An external box that links to your computer through an USB port or network cable, or an internal modem that is plugged directly to the motherboard inside the computer. || [[image:http://mnyiko.wikispaces.com/site/embedthumbnail/placeholder?w=200&h=87 width="200" height="87" caption="CREATOR: gd-jpeg v1.0 (using IJG JPEG v62), quality = 100 "]] ||
 * Network operating system || A network operating system is the software that runs on a server and enables the server to manage data, users, group, security, applications, and other networking functions. ||  ||
 * Firewall || A firewall is a device designed to permit or deny network transmissions based upon a set of rules and is frequently used to protect networks from unauthorized access. This is necessary because people that would like their computer to no be hacked or to be penetrated by a virus then a firewall will help. With I firewall a virus will be given to the user by choice. || [[image:http://mnyiko.wikispaces.com/site/embedthumbnail/placeholder?w=200&h=67 width="200" height="67"]] ||
 * Driver || A device driver simplifies programming by acting as translator between a hardware device and the applications or operating system that use it. Programmers can write the higher-level application code independently of whatever specific hardware device. ||  ||
 * Booster || Each type of network cable has a maximum usable length. If you go beyond that length, the signal will be too weak to be useful.

Of course, computers on a real network can easily be more than 200 metres apart. Therefor the network cable is split up into segments. Each segment is less than the maximum length allowed. Joining the segments together is a device known as a ‘Repeater’. || ||
 * WI-FI || WIFI is a mechanism that allows electronic devices to exchange data wirelessly over a computer network. || [[image:http://mnyiko.wikispaces.com/site/embedthumbnail/placeholder?w=200&h=117 width="200" height="117"]] ||