1. Revision on Communication hardware

2. Key words –
Bandwidth. Ping. leased line. ADSL. VPN.
Fibre optic –
Lighter. 200 megabytes per second. Longer than copper.
Can be bidirectional
Copper –
Twisted pair, most common communication thing.
Unshielded is not protected against electromagnetic things.
Network hardware –
Modem, router (provides an internet connection) , server, client. WAP. Ethernet cable. Hub. Switch (switches between devices. Network topologies (bus, star, ring etc.)
Wireless –
Can be 400 megabytes per second. Use on home networks. Connects to router. Walls can cause interference. WiFi, Bluetooth, microwave, laser, 3g/4g, satellite, infrared (needs a line of sight, wont work well outdoors).