Wireless Network Technologies - CompTIA A+ 220-1101 - 2.3
Summary
TLDRThe 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
📡 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.
Mindmap
Keywords
💡802.11 network
💡Frequency
💡Channels
💡IEEE
💡Wireless Spectrum
💡2.4 GHz Band
💡5 GHz Band
💡Bandwidth
💡Bluetooth
💡ISM Band
💡Personal Area Network (PAN)
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.
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