5 Fundamentals Of Computer Networks

A network is a collection of connected computers. These computers can communicate by sending data between themselves

Resources can be shared. E.g. Printers and Scanners A network manager can manage other computers over a network. E.g. Updating Software and Fixing Problems Data can be sent between computers without the need for external storage

Choice of Hardware Bandwidth Topology Wired or Wireless networks

The choice of cabling and other networking hardware can have a big impact on the speed of a network.

Bandwidth is the amount of data that can be transferred in a given time. The greater the bandwidth, the better the network’s performance potential. Bandwidth is shared between all active users, so performance can decrease if there are too many users.

The topology of the network (how the computers are laid out and connected together) can have a large impact on the network performance

Wired networks are usually much faster and more reliable. Wireless performance depends on how well a computer can pick up the signal but is rarely better than a wired connection would be

Transmission media are different ways of physically transferring data along a network

Fibre-Optic cables Twisted-pair copper cables Coaxial Cables Radio Waves

This is often referred to as ‘Ethernet cable’.

Inside the cable, there are eight wires which are twisted into pairs. This is to reduce interference from other signals and improve transmission speed.

Twisted cables have different ratings to indicate how quickly data can be transferred. E.g. Cat-5e can transmit at 1 Gbps. E.g. Cat-6 can transmit at 10 Gbps.

Fibre-optic cables are made of thin strands of glass which transmit binary data as pulses of light.

Fibre-optic cables have many advantages: Do not suffer interference. Very high bandwidth (100 TBps). Because of the lack of interference, fibre-optic cabling is appropriate for long distance communication such as undersea cabling

Coaxial cable is a wired transmission media where an insulated copper wire is surrounded by a metal mesh to protect it from interference. This is most often used for cable television

The amplitude (strength) of a radio wave decreases as it moves further from its transmitter. This is why WiFi signal loses strength further away from a Wireless Access Point (WAP)

WAN stands for Wide Area Network

A WAN is a collection of computers connected over a large geographical area. WANs are used by multinational organisations that have international offices they need to connect to. A WAN is usually rented from a large telecommunications company because WANs are expensive to set up

The Internet - It is the largest WAN in the world

PAN stands for Personal area network

A personal area network (PAN) is a network used to connect a single user’s devices in their workspace

An example of a PAN would be connecting your phone to a headset via Bluetooth

LAN stands for Local area network

A LAN is a collection of computers connected over a small geographical area. The LAN is set up and maintained by the organisation that uses it.