Wireless Network Technologies - CompTIA A+ 220-1101 - 2.3

Summary

The script discusses the technical aspects of 802.11 wireless networks, highlighting the importance of frequency ranges, specifically the crowded 2.4 GHz and the more spacious 5 GHz bands. It explains the concept of channels and their allocation by the IEEE, the role of governmental agencies in regulating wireless spectrum, and the impact of these regulations on network power and interference. The script also contrasts 2.4 GHz with 5 GHz networks, emphasizing the latter's greater number of available channels and bandwidth options, ideal for environments with high access point density. Additionally, it touches on Bluetooth technology, which operates in the 2.4 GHz ISM band, and its use in personal area networks with a typical range of about 10 meters.

Takeaways

• 📡 The 802.11 network operates on two main frequency ranges: 2.4 GHz and 5 GHz, with some standards utilizing both for communication.
• 🌐 Within these frequency ranges, there are specific channels assigned by IEEE for easier reference and management.
• 🔄 To avoid interference, access points in the same area should ideally operate on different wireless channels.
• 🏛 Governmental agencies regulate the use of wireless spectrum, dictating which frequencies can be used and setting power and interference limits.
• 📶 The 2.4 GHz band is commonly used but has limited non-overlapping channels (1, 6, and 11), leading to potential congestion in crowded areas.
• 🚀 The 5 GHz band offers a wider range of non-overlapping channels, providing more options for clear communication paths.
• 🔎 Devices can use bandwidths larger than 20 MHz for better throughput, including 40 MHz, 80 MHz, and up to 160 MHz.
• 📈 At higher bandwidths like 160 MHz, communication may occur in non-contiguous frequency areas.
• 🎧 Bluetooth also operates in the 2.4 GHz unlicensed ISM band, commonly used for short-range personal area networks.
• 🔗 Bluetooth devices typically have a communication range of about 10 meters, suitable for connecting peripherals to mobile devices.
• 🏭 Industrial Bluetooth standards can extend communication distances beyond 100 meters, but this is less common for consumer devices.

Q & A

What are the two primary frequency ranges used by 802.11 networks?

The two primary frequency ranges used by 802.11 networks are 2.4 GHz and 5 GHz.

Why is it important to be aware of the frequency and channels used in 802.11 networks?

It is important to be aware of the frequency and channels to avoid interference and to ensure efficient communication within the network.

How does the IEEE categorize the different frequencies for easier reference?

The IEEE assigns numbers to these frequencies, allowing for easier reference to specific channels or frequency bands in use.

What is the significance of using different wireless channels for multiple access points in the same area?

Using different wireless channels for multiple access points helps to reduce interference and improve the overall performance of the network.

Which governmental agencies are typically responsible for managing the wireless spectrum?

Governmental agencies responsible for managing the wireless spectrum vary by location but are tasked with regulating the use of frequencies for 802.11 networks.

What are the typical regulations set by these governmental agencies for 802.11 networks?

Regulations often include specifying the allowed frequencies, maximum power usage, and limits on interference caused by 802.11 networks.

Why are 5 GHz networks more popular than 2.4 GHz networks?

5 GHz networks are more popular due to the availability of more channels and the ability to use larger bandwidths, leading to better throughput and less congestion.

What are the three separate 20 megahertz bandwidths for 2.4 GHz networks as per IEEE channels?

The three separate 20 megahertz bandwidths for 2.4 GHz networks are IEEE channels 1, 6, and 11, ranging from 2412 MHz to 2482 MHz.

What is the significance of the 5 GHz spectrum in terms of channel availability compared to 2.4 GHz?

The 5 GHz spectrum offers many more 20 MHz channels than the 2.4 GHz band, providing more options for avoiding interference and improving network performance.

What does ISM stand for and why is it significant for Bluetooth and 802.11 networks?

ISM stands for Industrial, Scientific, and Medical. It is significant because it refers to the unlicensed part of the 2.4 GHz band that can be used by anyone without special government licensing.

How does the range of Bluetooth devices typically compare to that of industrial Bluetooth?

Consumer Bluetooth devices typically have a range of about 10 meters, while industrial Bluetooth standards can extend the range to over 100 meters.

Outlines

00:00

📡 Technical Specifications of 802.11 Networks

This paragraph introduces the technical aspects of 802.11 networks, focusing on frequency usage and channel allocation. It explains the distinction between 2.4 GHz and 5 GHz frequency ranges and the importance of using different channels to avoid interference. The IEEE's role in assigning channel numbers for easier reference is highlighted. Additionally, the paragraph touches on governmental regulations that dictate the use of specific frequencies, power limitations, and interference controls. The comparison between 2.4 GHz and 5 GHz networks is also mentioned, setting the stage for a visual representation of the popularity of 5 GHz networks.

Keywords

💡802.11 network

The term '802.11 network' refers to a set of wireless networking standards that use the 802.11 protocol to enable wireless local area networks (WLANs). In the video, it is the main subject, discussing the technical specifications necessary for their operation, such as frequency bands and channels. The script mentions how different 802.11 standards utilize either the 2.4 GHz or 5 GHz range, or both, for communication.

💡Frequency

Frequency in the context of the video pertains to the specific radio wave bands used for wireless communication. It is crucial for 802.11 networks as it determines the range and capacity of the network. The script explains that there are two primary frequency ranges used: 2.4 GHz and 5 GHz, each with its own set of channels and regulatory considerations.

💡Channels

Channels are specific groups of frequencies within a frequency range that are used to transmit data in wireless networks. The IEEE assigns numbers to these channels for easy reference. The script emphasizes the importance of using different channels for access points in the same area to avoid interference, highlighting the limited number of channels in the 2.4 GHz band and the abundance in the 5 GHz band.

💡IEEE

The IEEE, or the Institute of Electrical and Electronics Engineers, is a professional organization that sets standards for technologies worldwide. In the script, the IEEE is mentioned as the body that assigns numbers to wireless channels, facilitating the identification and use of specific frequencies in 802.11 networks.

💡Wireless Spectrum

The wireless spectrum refers to the full range of frequencies that can be used for wireless communication. The script discusses how governmental agencies manage this spectrum, dictating which frequencies can be used for 802.11 networks and setting limits on power and interference to ensure efficient use of the spectrum.

💡2.4 GHz Band

The 2.4 GHz band is a specific range of the wireless spectrum that is commonly used for 802.11 networks. The script describes it as having limited channels (1, 6, and 11) and being prone to interference due to its widespread use, which has led to the exploration of the 5 GHz band.

💡5 GHz Band

The 5 GHz band offers a wider range of frequencies for wireless communication, providing more channels and less congestion compared to the 2.4 GHz band. The script illustrates the popularity of the 5 GHz band due to its ability to support more access points and higher bandwidths, resulting in better performance.

💡Bandwidth

Bandwidth in the context of the video refers to the range of frequency within a channel that is used to transmit data. The script explains that beyond the basic 20 MHz bandwidth, 802.11 networks can utilize larger bandwidths like 40 MHz, 80 MHz, or even 160 MHz for higher throughput, although this may involve non-contiguous frequency areas.

💡Bluetooth

Bluetooth is a wireless technology standard used for data transmission over short distances, commonly employed in connecting peripherals to mobile devices. The script mentions that Bluetooth operates in the 2.4 GHz unlicensed ISM band, sharing the frequency with 802.11 networks but typically limited to a personal area network of about 10 meters.

💡ISM Band

The ISM band, which stands for Industrial, Scientific, and Medical, is a part of the 2.4 GHz spectrum that does not require special government licensing for use. The script explains that both Bluetooth and 802.11 networks commonly utilize this band due to its unrestricted access.

💡Personal Area Network (PAN)

A Personal Area Network is a computer network used for communication among computers and devices that are in close proximity to a person. The script refers to Bluetooth devices operating within about 10 meters as part of a PAN, emphasizing the short-range nature of typical Bluetooth communications.

Highlights

Technical specifications for 802.11 networks include awareness of frequency in use and channel assignments.

802.11 standards use 2.4 GHz and 5 GHz ranges, with some utilizing both for communication.

IEEE assigns numbers to frequencies for easier reference of channels in 802.11 networks.

Using different wireless channels for multiple access points in the same area can prevent interference.

Governmental agencies manage wireless spectrum regulations, dictating frequency use and power limits.

2.4 GHz networks, as per IEEE, include channels 1, 6, and 11 with a 20 MHz bandwidth each.

The 5 GHz spectrum offers more channels than the 2.4 GHz band, facilitating better spectrum availability.

Higher bandwidth options like 40, 80, or 160 MHz provide better throughput for 802.11 networks.

At 160 MHz bandwidth, 802.11 networks utilize two separate non-contiguous areas for communication.

Bluetooth networks operate in the 2.4 GHz unlicensed ISM band, facilitating wireless peripherals.

The 2.4 GHz unlicensed ISM band is available for anyone to use without special government licensing.

Bluetooth devices typically operate within a 10-meter range, forming a personal area network.

Industrial Bluetooth standards can extend communication distances to over 100 meters.

Consumer Bluetooth devices are generally limited to a 10-meter range.

The comparison between 2.4 GHz and 5 GHz networks highlights the popularity of the 5 GHz band.

Visual representation helps understand the advantages of the 5 GHz networks over 2.4 GHz.

Transcripts

If you're using an 802.11 network,

there are a number of technical specifications

that you need to be aware of.

One is the frequency in use.

You may have already seen in the 802.11 standards video

that there are many standards that use the 2.4 GHz range,

and other standards that use the 5 GHz range, and some of them

use both of those ranges to be able to communicate.

You also have to keep in mind that there

are separate channels within those frequency ranges

that can be used.

These are groups of frequencies.

And the IEEE has assigned numbers to these frequencies

so that we can much easier refer to which

channel we happen to be using.

That's why we often say if you're using multiple access

points in a particular area, you may

want to make sure each of the access points

is running on a different wireless channel.

And depending on where you are in the world,

there's probably a governmental agency

that's responsible for managing the wireless spectrum

or the frequencies that you would

use for these 802.11 networks.

These regulations often dictate exactly which

frequencies should be used.

They'll specify the maximum amount of power that

can be used on those networks.

And they'll set requirements and limits

over how much interference can be caused by these 802.11

networks.

We often see the 2.4 GHz and 5 GHz

networks compared with 802.11.

But I thought it'd be nice to see

a visual representation of why the 5 GHz

networks are so popular.

Let's start with 2.4 GHz networks.

These are the networks commonly seen as IEEE's channels 1, 6,

and 11.

And these are three separate 20 megahertz bandwidths

that range from 2412 MHz through 2482 MHz.

And that's where we get the 2.4 GHz band information.

These are the only channels available in 2.4 GHz.

As you can see, there are three to choose from.

And if you're in an apartment complex

with many 802.11 wireless networks,

you'll easily find a lot of activity on all three

of those channels.

Because of these limitations for 2.4 GHz,

we had to find some other available frequencies to use.

So we started using the 5 GHz spectrum.

Everything that is on this 5 GHz list that is not red

can be used to communicate.

So you can see, there are many more 20 MHz channels

available on a 5 GHz spectrum than there ever was on 2.4 GHz.

This allows you to easily find some available spectrum

in your area, especially if there

are a lot of access points being used simultaneously.

You may be using larger bandwidth than 20 MHz

to communicate because you can get much better throughput

that way.

So it may not be 20 MHz channels that you're choosing.

It may be a 40 MHz bandwidth, an 80 MHz bandwidth,

or the current largest 160 MHz bandwidth.

You can see when you get to 160 MHz

that there are really two separate non-contiguous areas

available to be able to communicate

at such a large bandwidth.

Not only do we often use these 802.11 wireless networks,

we also extensively use Bluetooth networks.

This effectively removes the wires from our peripherals

that we connect to our mobile devices.

So if you're using a headset, if you

have a set of external speakers, or you

have an external keyboard that you use on your computer,

it's probably using Bluetooth to communicate.

Bluetooth also uses the 2.4 GHz band.

The part of 2.4 GHz it uses is the unlicensed ISM part

of the band that stands for industrial, scientific,

and medical.

This is an area of the 2.4 GHz band

that doesn't require you to get any special licensing

from the government.

Anyone can use these particular frequencies.

And that's why Bluetooth and 802.11 commonly

use the 2.4 GHz band.

Bluetooth devices generally only communicate

in a small area around you.

We often refer to this as a personal area

network because of that.

So most of the headsets and other devices you'll use

will probably operate to about 10 meters in distance.

If you're in an environment that uses industrial Bluetooth,

there are additional standards available that

can increase that distance to over 100 meters.

But if you're using consumer devices,

you're probably not using a 100 meter distance

between you and your headset.

Instead, we can use the Bluetooth standards that

limit that to about 10 meters.