Networks Holistically

A computer network is a network of connected computers (computers meaning anything from a PC to your smart fridge).

Just like most IRL ‘networks’, computer networks exist to share information and resources.

Imagine that you share an apartment with four other people.

Your apartment has certain resources, like an oven, a washing machine, or a bathroom.

Imagine if every person in your apartment needed to have their own oven to make food.

That’s stupid.

It’s stupid because everyone in the apartment can walk over to the oven, understand what the buttons say, operate it, and tell other people that they’re using the oven.

This is possible because all the roommates have legs, all roommates are able to read the buttons on the oven, all ovens operate in a similar way, and all roommate speak a common language.

This is a sort of network. A series of conditions that make communication possible between individuals and make communication possible with resources.

Taking this to the computer network, you will often hear it explained with printers.

So imagine you score a job in a nice office, this office has six computers and one printer. Your job is to print fliers (idk what people do in offices tbh).

In order for each computer to be able to print fliers:

  1. Each computer must have a physical (or wireless (but it’s still physical as it’s done with microwave transmission)) way to contact the printer.
  2. The printer and the computer must know how to exchange information in a way they will both understand. (speak the same language)
  3. The computer must know how to operate the printer.
  4. The printer must work like a printer and follow a standard of operation shared between all printers (like an oven).

This is simplified but you get the idea, this is a computer network.

A network can be as small as two computers connected with a cable and as large as the entire internet.

Networks - in physical parts.

Computers don’t have vocal chords or legs, they need special ways to communicate with each other.

Laptops with an ethernet port have a wired connection through a thing called a Network Interface Card (or NIC).

These are the means through which a computer can be connected through a cable to another computer. A wired NIC is hiding behind the ethernet port on a computer.

The connecter is an ethernet cord AKA a copper ethernet cable AKA an Un-shielded twisted pair copper cable AKA a UTP AKA a RJ45 connecter.

You’d think this cable was on the run from the government. Many names for the same thing is just something you need to get used to.

This is a RJ45 connecter (ethernet cable) Image

Here is a NIC with an RJ45 connecter plugged in Image

NICs are cards with a Media Access Control address or a MAC address.

On ethernet or on wireless your device is identifiable by its MAC address.

MAC addresses are hard-coded, which means they can never be truly changed, they can be spoofed for various purposes, but they can not be changed.

If your device has both a wireless and a wired connection it will have two MAC addresses.

If you want to use a wired ethernet connection but your laptop does not have an ethernet port, you can buy an adapter that plugs into your HDMI, or High-Definition Multimedia Interface, port on one end and has an ethernet port on the other.