Network Hardware: Computer Science OCR: GCSE (9:1)

Switch

A network device that directs packets of data on a local area network. It uses MAC addresses to route traffic to the correct device

Hub

This dumb network device has no means of storing MAC addresses so it sends all packets to all devices connected to it

Router

This network device joins two LANs or a LAN to a WAN. It uses the IP address on a device to route traffic to another router, which passes it on to its own LAN. A router connects your home LAN to the internet

Network Interface Card

A hardware component that connects a device to a computer network. Every networked device needs one, it has a unique MAC address

MAC Address

Unique identifier assigned to every NIC by the manufacturer. Switches use this to route packets. Short for Media Access Control Address, it can't be changed. Consists of six bytes written in hex, like this: A1:9E:13:7C:FF:04

Fibre Optic

This transmission media is a cable that has a glass core. Data is sent as pulses of light and these cables have much higher bandwidth and suffer less interference than copper but are expensive

Copper

The metal used inside standard data cables, this media is cheap and reliable but has more limited length and bandwidth

Wireless Access Point

Network component which allows Wi-Fi enabled devices to connect to a network. Usually built into a "home hub" internet router, and can be seen on the ceilings of schools and public buildings

Media

The method of connecting devices to a network, types are copper cable, fibre optic cable and wireless

Congestion

Caused by too many devices being connected to a network at once, or all the traffic filling up the bandwidth, this causes a network to slow down

Obstruction

An obstacle such as a walls or floor. It can reduce the strength of the wireless signal which means lots of packets get lost and have to be resent. This reduces bandwidth and slows down the connection

IP Address

A unique number that identifies each device on the network, this can change every time and is usually assigned by a Router or Switch. Traditionally four bytes written in decimal like this: 10.124.7.32

B1:5B:1A:72:EF:35

This is an example of a MAC address

192.0.1.44

This is an example of an IP address (in format IPv4)

Owned

All the hardware devices and transmission media that make up a LAN are this

Satellite

You would only see this device used in a WAN that spans the globe, never a LAN

Local

Another word for nearby, it's the L in LAN

Dumb

A hub doesn't know anything about the devices connected to it, so we say it is this

Smart

A Switch knows all the MAC addresses of its connected devices so it is intelligent, also called this

Smartphone

A phone that runs apps and has a network connection, it connects wirelessly to a LAN through a Wireless Access Point