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When looking at the list of components that make up the real lifeblood of a network you have to begin by talking about the network adapter (or the NIC).
NIC stands for Network Interface Card. It’s the lowest cost most necessary component to have in order for computers, servers, printers, copiers and any other devices to allow them to actually connect to a network.
Multiple NICs?
Now you’re not confined to just 1 network card or adapter on each computer or device.
Some computers can use more than one network adapter card and some network adapter cards can have more than one physical port or interface on them for use with connecting to the network. There are several types of ports you’ll see on different network adapter cards.
Connectors Ports On NICs
The most common you’ll see is an RJ45 connector which is similar to an RJ11 which you see on like the old analog phone connectors, and may or may not be interchangeable but they aren’t actually interchangeably functional-wise.
These tend to take Ethernet cables like Cat5, Cat5e, Cat6, Cat6e and most recently Cat7…it allows them to connect (those types of Ethernet cables can connect) using the RJ45 port.
You’ll also find NICs that have what are referred to as SFP ports as well as SC, LC and GBIC ports that allow fiber-optic cables to connect to them.
There’s more about fiber optic cables and connectors later…
Just know for now that fiber optic uses light signals down a fiber optic glass cable that the GBICs and the other adapters on the ends of those fiber optic cables actually convert to electrical signals or convert from electrical signals to light transmitting down those fiber optic cables.
The proper cable connects into the port on this NIC card.
Then this NIC card connects usually to the motherboard of the computer or the device itself. I say this “device” because you can look at a network printer as one of the first examples of something that has a network adapter card for connecting to the network that isn’t technically classified as a computer even though modern network printer copiers scanners are essentially high-powered computers made for their tasks.
Built-In or Connected Manually?
Now most if not all desktop and laptop modern-day computers come with built-in network adapter cards.
However with many of the desktops you still find today the network card is not integrated into the motherboard so you have the capability of upgrading it to handle different cable connections or adapters or different speeds – these network cards also come in multiple different speeds.
So you can typically find them in the standard speed that’s being used right now more prevalently than you can slower speeds but they are out there.
We’re going to talk more about this in a later chapter as I’m going to wrap up this lesson on network cards right now.
But just know for now that each NIC (each network adapter card) is hard-coded with its own unique MAC address – MAC stands for Media Access Control and it’s hard-coded with this address number when the manufacturer BY the manufacturers when the manufacturers actually make them at the factory.
