Communication systems p1

Communication system

A system that allows people and systems to transmit and receive data and information electronically over a network.

Network

A collection of hardware and software that enables communication between devices.

LAN (Local Area Network)

A network that connects devices over a small distance, commonly used in businesses and schools.

WAN (Wide Area Network)

A network that connects devices over a large distance, such as the internet.

Node

Each device on a network is referred to as a node.

NIC (Network Interface Card)

A device required for a computer to connect to a network, which can be built into the motherboard or added separately.

Server

A specialized software or hardware device that provides processing services to network users, such as file sharing and internet access.

File server

A dedicated computer that stores files and application software for network access.

Print server

A computer that manages print tasks and queues print requests from users.

Web server

A server that provides access to the internet.

Hub

A non-intelligent device that connects nodes in a network, passing transmissions to all devices.

Switch

An intelligent device that connects nodes and directs signals only to the intended receiver.

Bridge

A device that connects two LANs using the same protocol, often used in multi-level buildings.

Gateway

A device that connects two networks using different protocols, typically linking a LAN to the internet.

Router

A device that directs messages between networks with similar protocols and can translate between different protocols.

Modem

A device that connects a network or computer to the internet, converting digital signals to analog and vice versa.

Transmission media

The medium through which messages are sent, including wired and wireless options.

Twisted pair cable

A type of wired transmission media using two insulated copper wires twisted together, offering low cost but slower speeds.

Coaxial cable

A wired transmission medium with a thin core of copper wire, more reliable than twisted pair but less flexible.

Fibre optic cable

A high-speed wired transmission medium made of thin glass strands, capable of long-distance transmission.

Wireless transmission

A method of communication using electromagnetic waves to connect nodes without physical cables.

Microwaves

A wireless transmission method requiring direct line of sight, limited to 40-50 km between towers.

Satellites

Microwave stations in the sky that facilitate communication over long distances.

Wireless LANs (WiFi)

A wireless network technology allowing devices to connect without cables.

Bluetooth

A short-range wireless communication system that does not require line of sight.

Infrared

A wireless transmission method requiring line of sight, used for short distances like remote controls.

Mobile phones

Devices that transmit data using radio waves, organized into cells with base stations.

3G

The third generation of mobile technology, enabling mobile internet and video calling with speeds up to 2 mbps.

4G

The fourth generation of mobile technology, significantly faster than 3G, supporting high-definition video and mobile TV.

5G

The latest mobile technology, offering faster speeds and larger bandwidth to support more devices simultaneously.