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TechKnowSurge Catalog Videos What’s Network Media?
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What’s Network Media?

Network media refers to the physical or wireless means by which data travels between devices, with three primary options: copper cable, light-based transmission, and radio signals. Each method encodes binary data differently but serves the same fundamental purpose of enabling device-to-device communication.

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About this video

Network communication depends on a physical or wireless medium through which data travels between connected devices. That medium — referred to as network media — comes in three primary forms: conductive cabling such as copper wire, light-based transmission using photons, and radio frequency signals. Each approach is capable of representing the binary language of computers, encoding ones and zeros in a way suited to its physical properties. Copper cabling carries data by switching electrical current on or off, where the presence of voltage represents a one and the absence represents a zero. The specific voltage level is largely irrelevant — what matters is simply whether current is flowing. Light-based transmission works on a similar on-off principle, with light pulses representing ones and the absence of light representing zeros, a concept that mirrors older signaling methods like Morse code. Radio wave transmission follows the same binary logic but requires modulation of the wave itself to encode data, making it somewhat more complex at the signal level. All three methods have distinct advantages and disadvantages in real-world networking environments, including differences in speed, distance, interference resistance, and cost. While those trade-offs are addressed in greater depth elsewhere, grasping how each medium physically carries binary data provides the conceptual groundwork necessary for understanding network infrastructure, cabling standards, and wireless technologies at a professional level.

What you'll learn

What's covered

Network Media & Connectivity

Aligned to

CompTIA Network+
1.5 Compare and contrast transmission media and transceivers.
1.1 Explain concepts related to the Open Systems Interconnection (OSI) reference model.
Cisco CCNA
1.3 Compare physical interface and cabling types
Cisco CCST Networking
3.1 Identify cables and connectors commonly used in local area networks
3.2 Differentiate between Wi-Fi, cellular, and wired network technologies

Key terms

Physical Layer
Layer 1 of the OSI model, responsible for the transmission of raw bits over a physical medium.
Bandwidth
The maximum rate of data transfer across a network path, typically measured in bits per second.
Network Media
The physical or wireless means through which data is transmitted between devices, including copper cable, fiber optic, and radio signals.
Copper Cable
A conductor-based network medium that transmits data by varying electrical voltage to represent binary ones and zeros.
Fiber Optic
A network transmission medium that carries data as pulses of light through a glass or plastic strand rather than as electrical signals over copper, enabling very high speeds and immunity to electromagnetic interference. Fiber optic cables are used for high-bandwidth runs such as backbone links, long-distance WAN connections, and data center interconnects.
Wireless
A network medium that transmits data using radio waves manipulated to represent binary ones and zeros.
Binary
The base-2 number system that uses only the digits 0 and 1; the native language of digital computers, which store and process data as electrical on/off states.

Transcript

The reason why we'd want to start connecting our phones, our computers, and other devices all together is so we can get network services, for things like communicating amongst all of these devices. But how do we communicate amongst these devices?

Somehow we need to connect these devices together so we can communicate, and the way we do that is known as the network media — what the actual data is being transferred across. We pretty much have three options. We could run a cable between these two; usually we use copper cable to do that, but there are other conductors that we could use as well. Or we could send radio signals back and forth between these two devices. Or we could use photons: we can actually shine light from one to the other so we can pass information.

Sending a signal with light

For instance, I could use this flashlight to send a message to you. I could turn it on and off in some sort of pattern to send a message. I could use something like Morse code. Morse code uses dots and dashes, so a dot would just be a quick flash of the light, versus a dash would be an extended presence of that light — I could hold it open for a little bit longer. So a dot and a dash, and then I could send you letters, which you can translate into words, and that's a way of communicating back and forth.

When it comes to your computer, your computer speaks in ones and zeros, so that's pretty simple. I could turn the light off for a zero and I could flash the light on for a one, and as fast as I could flash, I could send you some sort of signal. So that is a way I could send a signal through light.

Sending a signal through copper and radio

I can do the same thing with a cable. If I've got a copper cable running between two devices, all I need to do is turn it off — no electrons flowing across it — and that represents a zero. I could turn it on, and that could represent a one. And it wouldn't really matter what voltage it is: 5, 10, 12, 24, 110. It really doesn't matter what the voltage is. Just turning it on with a voltage would represent a one, and turning it off would represent a zero.

Sending radio waves is a little more complicated than that, but it still can be done. We can send radio waves, and we can manipulate those waves to represent ones and zeros.

So now we've got our three different methods: our copper method, or our conductor, where we send electrons; we could send photons; or we could send radio signals. Each one of these methods has its pros and cons. But we at least have a basis now of how we can send messages between two devices.

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