Routers and Modems
In the good old days (in technology, that means anywhere from 5 to 15 years ago), you only needed a modem to connect to the Internet. It’s still all you’d need in the event only one device needed to access Netflix. However, a router is required when more than one device needs to access the Internet (or another device with an IP address).
A modem is like a translator; it converts signals it receives into the proper, or needed, format. Modem stands for MOdulator and DEModulator, which is a nod to its analog origins—encoding analog signals into digital ones so they can be transmitted, then decoded on the other end.
Again, the router enables multiple devices to connect to the Internet. For purposes of this discussion, we’re going to talk about home routers, the ones you use for binge watching. Service Providers use backbone routers that are much larger, have extensive routing tables, and cost the same as a private, low-end jet. Nowadays, most modems come with built-in routers, further muddying their distinct difference.
Think of a router as you do the post office. They need the correct address in order to deliver a package, right? A router needs the correct IP address to know where to send its information, which is maintained in packets. Don’t worry, we’ll get to packets later. The router takes a look at the destination address, then figures out how to best get there by examining the routing tables it maintains (think Google Maps).