The Absolute Beginner’s Guide to Understanding Networks

Networks are about communication

When you are new to the high-tech industry and first start digging into networking concepts, you may find it intimidating. Words like bits, bytes, MAC, protocol, and others can sound like a jumble of terms that make no sense—a feeling that comes with anything new or unfamiliar. To make matters worse, engineers tend to resort to acronyms that sound almost like another language altogether.

I faced that very same situation nearly 30 years ago when I began my career in IT. I still remember how awkward it felt at first. Since then, I have found ways to explain some of the concepts more simply.

While this set of blogs focuses on the CCNA certification, the journey must begin somewhere. Forget the complicated aspects of network technology. Let’s start by peeling back the layers to something more basic: the what rather than the how. It’s true that networks use complex processes and methods, but why? What is the goal?

First and foremost, networks are about communication.

Having a conversation

Humans have a hard-wired need to communicate with each other. Some of this stems from the need for self-expression, relationship-building, the exchange of ideas, and the development of a sphere of influence beyond oneself. Take a casual look around on a given day, and you will see this played out constantly, whether it be in a conference room, coffee shop, village, or roadside fruit stand.

Nearly every conversation on the planet (and perhaps even off of it) shares certain basic elements. This can shed light on the principles of networking, as you will see later.

Basic communication model

Every conversation follows the same basic pattern, which public speaking experts call the communication model. The model features a sender (the person speaking), a receiver (the one listening), a message (what is being communicated), and a medium (how the message is transmitted). The process typically happens as illustrated by Figure 1.

• Sender: Has some sort of idea or message to convey.
• Encoding: Sender turns the idea into words.
• Message: Contains a series of words ready to send.
• Medium: Words are sent by analog sound waves to the receiver.
• Decoding: Receiver hears the words, interprets them, and understands the original idea.

Networking is about computers having a conversation

Now let’s apply the same logic using two computers instead of people, because the process is ultimately nearly identical.

• Sending Device: Has data it wants to transmit to another computer.
• Encoding: The sending device breaks the data into chunks or packets, adding information about where it came from and where it is going (called encapsulation).
• Message: A message is a series of these packets (the message broken up into sections).
• Medium: Packets are transmitted as electrical impulses (bits) over a wire (the network).
• Decoding: The receiver converts the bits back into packets and reassembles the entire message for use in some form.

Let’s use email as an example of network communication

To make this more practical, consider how you might send an email to someone else using your phone or personal computer.

• Sending Device: You type out an email message and press Send.
• Encoding: Your computer takes the email and breaks its contents into a series of packets.
• Message: The stream of packets contains all the pieces of your original email, including your email address and that of the person you are communicating with.
• Medium: Your computer converts those packets into electrical impulses (bits) on a wire and transmits them on the network based on the sender’s address.
• Decoding: Your recipient’s computer converts the bits back into packets, extracts the information, and reassembles the data back into an email message for them to read.

Some final thoughts

Yes, the mechanics of the entire operation have many moving parts, and with that comes complexity. That alone can make trying to understand the process intimidating. Even so, the core concept is simply about communication, namely, having a conversation. Always go back to the basics before tackling the deeper principles. For a career in the IT field, understanding these elements can make all the difference between success and failure. This is where your journey can start!