Networks - Intro

Put a phone in flight mode, with the Wi-Fi off too, and most of it goes quiet. The camera still works, and so does the calculator. Messages, maps and videos all stop, because almost nothing you do on a phone happens on the phone alone. The chapters before this one looked at a single computer on its own: its processor, its memory and its software.

This chapter joins computers together, from two devices on a desk all the way up to the whole Internet.

If networks are new to you, start with What a network is, and why bother. It gives the definition the rest of the chapter stands on, and why joining up is not all good news. If time is short, go to LAN, WAN and PAN, because the difference between a LAN and a WAN is set on every board. A common slip is giving only one side of a difference. That video shows you how to give both halves. Wired and wireless weighs a cable against Wi-Fi for a real place, like an airport. A common slip here is calling the cable itself faster, when the mark is for saying the data is sent faster. What makes a network fast pins down bandwidth, latency and range. A common slip here is describing bandwidth when the question asked about latency. Network topologies draws each shape, then cuts a cable in it. The boards differ on which shapes they ask for, and that video says so at the start. A common slip there is saying that one broken computer stops a whole bus network. The hardware that builds a network gives every box its job. A common slip here is treating a switch like a server, as if it stored the data itself. Client-server and peer-to-peer comes next, and it is about which computer asks and which one answers. If it is the web you need, go to The Internet, DNS and hosting. A common slip there is mixing up the web server with the domain name server. You can find any of these videos by searching its name or its code. The quickest way is the scholafly.com website, which indexes every video in every subject.

Next in the chapter is What a network is, and why bother. Hopefully that's next in your feed, but if not, search for ScholaFly C S oh seven, oh one.

Every other video is on scholafly.com too, easy to search by video code or by keyword. Whatever you're revising, go there and have a look, or, watch the next video.