Network is a collection of computers devices connected together via communications devices and transmission media.
COMMUNICATIONS DEVICES:
Hardware component that enables a computer to send (transmit) and receive data, instructions, and information to and from one or more computers.
| MODEM: Device that enables a computer to communicate over analog networking media |
| WIRELESS ACCESS POINT: Device on a network that connects wireless devices to that network. |
| HUB: Device that provides common central connection point for nodes on network. |
| SWITCH: Devices used to connect multiple devices on a single network. |
| ROUTER: Devices that connects multiple networks together. |
| NETWORK INTERFACE CARD: An adapter card that connects computers on a network. |
| REPEATER: Device that enhances the weaken signal and repeat it at its original strength. |
The materials or substances capable carrying one or more signals.
PHYSICAL: Send signals through cable, wire or tangible materials.
| Twisted pair cable: Consists of pairs of copper wire that are twisted together. |
| Coaxial cable: Consisting of centre wire inside a grounded, cylinderical shield, capable sending data at high speed. |
| Fiber optic: Consists of dozens or hundreds of thin strands of glass or plastic that use light to transmit signals. |
WIRELESS: Sends signals through air or space.
| Infrared: Sends signals using infrared light waves from one device to another. |
| Microwaves: Radio waves that provides high speed signals transmission using electromagnet radio wave. |
| Cellular Radio: Form o broadcast radio that is in wide use for mobile communication. |
| Broadcast Radio: Distribute radio signal through the air over long distances and short distances. |
| Communication satellite: Earth-orbiting devices that relays communication signals over long distances. |
| Bluetooth: Networking standard for every short-range wireless connection. |
| ADVANTGES | DISADVANTAGES |
| Hardware sharing - Network facilitate the sharing of hardware devices such printer. | Undesireable sharing - Viruses are easily spread over network and the internet. |
| Data and information sharing - Enables many people to access and share the same data such as database and group software development. | Security issues - A computer hacker can get unauthorized access by using different tools. |
| Facilitate communications - People communicate efficiently and easily via e-mail. | Network hardware, software and setup costs - Setting up a network requires an investments in hardware, software of network. |
| Internet access sharing - Small computer networks allow multiple users to share a single internet connection. | Illegal or undesireable behaviour - Typical problem include the abuse of company resources, distractions thet reduce productivity, software privacy. |