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

Summary

This script offers an in-depth look into the evolution of wireless networking standards, starting from 802.11a/b to the latest 802.11ax (Wi-Fi 6). It explains the differences in frequency bands, speeds, and technologies like MIMO used in these standards. It also touches on the practical aspects of setting up long-range networks, the challenges of interference, and the importance of adhering to regulations. Additionally, it covers RFID and NFC technologies, highlighting their applications in various settings.

Takeaways

• 📡 Wireless networks are now expected in many public places like restaurants and conference rooms, and they are standardized by the IEEE 802.11 committee.
• 🌐 The term 'Wi-Fi' is a trademark of the Wi-Fi Alliance, which tests the interoperability of wireless devices.
• 🔋 802.11a was the first wireless standard released in 1999, operating at 54 Mbps in the 5 GHz frequency range, but has less range than 2.4 GHz networks.
• 📶 802.11b, released around the same time as 802.11a, operates at 11 Mbps in the 2.4 GHz range, offering greater range but is susceptible to interference from other devices.
• 🚀 802.11g, released in 2003, is an upgrade to 802.11b, increasing speed to 54 Mbps while maintaining compatibility and operating in the 2.4 GHz range.
• 🔄 802.11n, also known as Wi-Fi 4, was introduced in 2009 and can operate at both 2.4 GHz and 5 GHz frequencies, with a maximum theoretical throughput of 600 Mbps.
• 🌟 802.11ac, or Wi-Fi 5, introduced in 2014, operates only in the 5 GHz range, supports up to 160 MHz channel bandwidth, and can achieve nearly 7 Gbps throughput.
• 🔋 802.11ax, or Wi-Fi 6, released in 2021, operates in both 2.4 GHz and 5 GHz frequencies and introduces OFDMA to improve efficiency in crowded areas.
• 📈 The progression of Wi-Fi standards has led to significant increases in speed and efficiency, with Wi-Fi 6 offering up to 9.6 Gbps theoretical throughput.
• 🏢 When setting up long-range wireless networks, such as connecting buildings, it's important to consider the use of directional antennas and local regulations.
• ⚠️ Safety and regulatory compliance are crucial when installing external antennas, and professional expertise may be necessary for proper setup.
• 🆔 RFID and NFC technologies are widely used for identification and communication purposes, extending to mobile devices for contactless payments and access control.

Q & A

What is the IEEE 802 committee responsible for?

The IEEE 802 committee is responsible for the standards of local area networks (LAN) and metropolitan area networks (MAN), including the wireless networking part, which is the 802.11 standard.

What does Wi-Fi stand for and who is responsible for its trademark?

Wi-Fi stands for 'Wireless Fidelity' and the trademark is held by the Wi-Fi Alliance, which is responsible for testing the interoperability of different wireless devices.

When was the 802.11a wireless standard released and what is its main frequency range?

The 802.11a wireless standard was released in October of 1999 and it operates exclusively in the five gigahertz frequency range.

What is the maximum speed of the 802.11a standard and why might it not be commonly used today?

The 802.11a standard operates at 54 megabits per second. It may not be commonly used today because it has been largely replaced by faster and more advanced standards.

How does the 802.11b standard differ from 802.11a in terms of frequency and speed?

The 802.11b standard operates in the 2.4 gigahertz range and has a maximum speed of 11 megabits per second, which is slower than the 54 megabits per second of the 802.11a standard.

What is the advantage of using the 2.4 gigahertz frequency range as used by 802.11b?

The 2.4 gigahertz frequency range tends to bounce off of devices rather than being absorbed, which can result in a longer range for 802.11b networks compared to higher frequencies.

What is the 802.11g standard and how does it relate to 802.11b?

The 802.11g standard was released in June 2003 and operates in the 2.4 gigahertz range like 802.11b. It is an upgrade that increases the speed to 54 megabits per second and is backwards compatible with 802.11b devices.

What is the difference between 802.11n (Wi-Fi 4) and its predecessors in terms of frequency and bandwidth?

802.11n (Wi-Fi 4) can operate at both five gigahertz and 2.4 gigahertz frequencies and supports wider channel widths of up to 40 megahertz, allowing for more data transfer compared to 802.11a, b, and g.

What is MIMO and how does it improve wireless network performance?

MIMO stands for Multiple Input Multiple Output. It is a form of communication that allows devices to transfer much more information simultaneously between the end station and the access point, improving wireless network performance.

What are the main differences between 802.11ac (Wi-Fi 5) and 802.11n (Wi-Fi 4)?

802.11ac (Wi-Fi 5) operates exclusively in the 5 gigahertz range and supports up to 160 megahertz of channel bandwidth, as well as multi-user MIMO, resulting in a maximum theoretical throughput of nearly seven gigabits per second, which is an improvement over 802.11n.

What is the main focus of the 802.11ax (Wi-Fi 6) standard and how does it address the issue of crowded wireless networks?

The 802.11ax (Wi-Fi 6) standard focuses on improving performance in crowded environments by introducing OFDMA (Orthogonal Frequency Division Multiple Access), which allows for more efficient communication in areas with a large number of users.

Outlines

00:00

📶 Evolution of Wireless Networking Standards

This paragraph introduces the prevalence of wireless networks in modern settings and the role of the IEEE 802 committee in setting standards for these networks. It explains the 802.11 standard and its various iterations, from 802.11a, which operates at 54 Mbps in the 5 GHz range, to 802.11b, which offers 11 Mbps in the 2.4 GHz range. The differences in range and speed due to frequency are discussed, as well as the interoperability testing conducted by the Wi-Fi Alliance. The paragraph also touches on the environmental factors affecting wireless signal propagation and the commonality of 2.4 GHz frequency conflicts with other devices.

05:02

🚀 Advancements in Wi-Fi Technologies

The second paragraph delves into the progression of Wi-Fi standards, starting with the introduction of 802.11g as an upgrade to 802.11b, offering increased speed while maintaining backward compatibility. It then discusses the 802.11n standard, also known as Wi-Fi 4, which operates at both 2.4 GHz and 5 GHz frequencies and introduces MIMO technology, significantly boosting data transfer capabilities. The summary also covers the 802.11ac standard, or Wi-Fi 5, which exclusively uses the 5 GHz band and supports up to 160 MHz channel bandwidth, further enhancing data transfer rates with multi-user MIMO capabilities. The paragraph concludes with the release of the 802.11ax standard, Wi-Fi 6, which addresses the challenges of high-density network environments with the introduction of OFDMA.

10:04

🔋 Overview of RFID and NFC Technologies

The third paragraph provides an overview of RFID technology, its applications in access control, manufacturing, inventory management, and pet tracking. It describes the functioning of passive RFID tags, which use radar technology for power, and mentions active RFID tags that have their own power source. The paragraph also introduces NFC, or Near Field Communication, explaining its use in mobile payments, device pairing, and as an access card, highlighting the convenience it brings to everyday life through the integration with smartphones and smartwatches.

15:07

🛠 Considerations for Long-Range Wireless Networks

The final paragraph discusses the practical aspects of setting up long-range wireless networks, including the need for directional antennas and the considerations for signal strength when connecting buildings. It touches on the importance of adhering to local and federal regulations regarding wireless communication, such as frequency availability and transmission power limits. The paragraph also addresses the safety requirements for outdoor antenna installations, including protection against lightning, and suggests the potential need for third-party expertise in such installations.

Keywords

💡Wireless Networks

Wireless networks refer to the interconnected infrastructure that allows devices to communicate without the use of wires. In the context of the video, they are the focus as they have become a common expectation in various settings like homes, businesses, and public spaces. The script discusses how these networks are standardized by the IEEE 802 committee, specifically the 802.11 standard for wireless networking.

💡IEEE 802 Committee

The IEEE 802 committee is a group within the Institute of Electrical and Electronics Engineers that is responsible for developing and maintaining standards for local area networks (LANs) and metropolitan area networks (MANs). The script highlights the committee's role in creating the 802.11 standard, which governs wireless networking technologies.

💡802.11 Standard

The 802.11 standard is a set of protocols that define the communication between devices in a wireless local area network (WLAN). The video script explains that this standard has various iterations, such as 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, and 802.11ax, each offering different capabilities and performance improvements.

💡Wi-Fi Alliance

The Wi-Fi Alliance is a non-profit organization that certifies products for interoperability within the wireless industry. In the video, it is mentioned that the term 'Wi-Fi' is a trademark of the Wi-Fi Alliance, which tests wireless devices to ensure they work well together, a critical aspect of wireless networking.

💡Frequency Range

Frequency range refers to the specific bands of radio frequencies used for wireless communication. The script explains that 802.11a operates in the 5 GHz range, while 802.11b and 802.11g operate in the 2.4 GHz range. The choice of frequency range affects the network's speed, range, and susceptibility to interference.

💡MIMO (Multiple Input Multiple Output)

MIMO is a method for increasing the capacity of a radio link by using multiple antennas at both the transmitter and receiver. The video script discusses how MIMO was introduced in the 802.11n standard and further developed in subsequent standards to allow for more simultaneous data transfers, improving network performance.

💡Throughput

Throughput refers to the rate of successful message delivery over a communication channel. The script provides examples of maximum theoretical throughput for various 802.11 standards, such as 54 Mbps for 802.11a and up to 600 Mbps for 802.11n, illustrating the performance improvements over time.

💡RFID (Radio Frequency Identification)

RFID is a technology that uses radio waves to identify and track tags attached to objects. The video script mentions RFID as another form of wireless technology, commonly used for access control and inventory management, and explains how it operates differently from traditional wireless networks.

💡NFC (Near Field Communication)

NFC is a set of protocols that enable short-range communication between devices. The script describes NFC as an extension of RFID technology used in mobile phones and smartwatches for contactless payments and device pairing, highlighting its convenience in everyday applications.

💡Signal Modulation

Signal modulation is the process of varying one or more properties of a periodic waveform, called the carrier signal, with a modulating signal that typically contains information to be transmitted. The video script explains that changes in signaling modulation in the 802.11ac standard allowed for more efficient data transfer over wireless networks.

💡OFDMA (Orthogonal Frequency Division Multiple Access)

OFDMA is a method of encoding digital data on multiple carrier frequencies, allowing multiple users to share the same channel. The script discusses how OFDMA was introduced in the 802.11ax standard to improve wireless network performance in crowded areas by allowing more efficient communication among multiple devices.

Highlights

Wireless networks are now a common expectation in public spaces like restaurants and conference rooms.

IEEE 802 committee is responsible for setting standards for wireless networks, including the 802.11 standard for wireless networking.

Wi-Fi is a trademark from the Wi-Fi Alliance, ensuring interoperability of wireless devices.

802.11a was the first wireless standard released in 1999, operating at 54 Mbps in the 5 GHz frequency range.

Higher frequency of 802.11a can result in less range due to signal absorption by objects.

802.11b operates at 11 Mbps in the 2.4 GHz range, offering longer range due to signal reflection.

The 2.4 GHz frequency range is shared with other devices like baby monitors and Bluetooth, leading to potential interference.

802.11g was an upgrade to 802.11b, increasing speed to 54 Mbps while maintaining 2.4 GHz operation.

802.11g is backwards compatible with 802.11b, allowing for a smooth transition and coexistence of devices.

802.11n, also known as Wi-Fi 4, introduced the ability to operate at both 2.4 GHz and 5 GHz frequencies.

802.11n supports channel widths up to 40 MHz and higher throughput with MIMO technology.

Theoretical maximum throughput of 802.11n can reach 600 Mbps with four MIMO streams.

802.11ac, or Wi-Fi 5, operates only in the 5 GHz band with support for up to 160 MHz channel bandwidth.

802.11ac introduces multi-user MIMO, allowing multiple users to communicate simultaneously over MIMO streams.

802.11ax, or Wi-Fi 6, supports operation at both 2.4 GHz and 5 GHz frequencies with various channel widths.

802.11ax introduces OFDMA to improve efficiency in crowded areas with many users.

The maximum theoretical throughput of 802.11ax is 9.6 Gbps with eight streams of multi-user MIMO.

Wireless networks require consideration of local and federal regulations regarding frequency use and signal strength.

RFID technology is widely used for access control, inventory management, and pet tracking.

NFC extends RFID technology to mobile devices for contactless payments and device pairing.

Transcripts

Wireless networks have become almost commonplace

in our homes and businesses, and we've almost

come to expect that when we walk into a restaurant

or a conference room that there will

be a wireless network available to use.

The standards for these wireless networks

come from an IEEE LAN MAN standards committee.

This is the IEEE 802 committee.

And the wireless networking part of this committee

is the 802.11 standard.

But as you're probably aware, there

are many different wireless standards.

And in this video, we'll step through each one

of those 802.11 standards.

Instead of referring to these as 802.11 wireless networks,

you'll often see this abbreviated as a W-Fi network.

This is a trademark from the Wi-Fi Alliance, who's

responsible for testing the interoperability of all

of these different wireless devices.

The first standard we'll look at is the one

from the very beginning.

It's the 802.11a.

This is one of the very first wireless standards

that was released back in October of 1999.

It's a standard that operates exclusively in the five

gigahertz frequency range.

It can use other frequency ranges with special licensing,

although these days you don't often see very many 802.11a

networks still around.

The 802.11a wireless standard operates at 54 megabits per

second.

And although this doesn't seem very fast now,

back in 1999 when this was first released,

that was a great deal of speed on a network that suddenly

was able to operate wirelessly.

Because we are operating at five gigahertz frequencies,

we don't tend to have the same range as lower frequencies such

as the 2.4 gigahertz range that's used by 802.11b.

With these higher frequencies, the objects around us tend

to absorb the signals, whereas with 802.11b they tend

to bounce off of those devices.

And therefore, we get a little bit more distance

from a 2.4 gigahertz based network.

As I mentioned, it's not common to see 802.11a in use these

days.

And very often this will be a type of network

that has already been upgraded to a much faster and newer

standard.

And about the same time that 802.11a was released,

the IEEE also finalized the 802.11b standard.

This is not an upgrade to the a.

Instead this is a completely different standard

that operates with different frequencies

and different speeds.

802.11b operates in the 2.4 gigahertz range and its maximum

speed is 11 megabits per second, which is certainly much slower

than the 54 megabits per second we were able to get with

802.11a.

So why would we choose the slower 11

megabit per second wireless standard

when a 54 megabit standard already was available?

In many cases, this is associated

with the frequency in use.

As I mentioned earlier, 2.4 gigahertz frequencies

tend to bounce off of devices instead of being absorbed.

And therefore, we get a bit longer distance

in 2.4 gigahertz networks.

This, of course, will depend on the type of environment.

If you're in a warehouse, you may choose 802.11a

because there's so much open space.

But if you're in an office setting with a lot of people

and desks, you may choose 802.11b because that frequency

works a lot better in that environment.

One challenge we have with this 2.4 gigahertz range

is that wireless networks are not the only devices that

can use those frequencies.

It's very common to see things like baby monitors,

cordless phones, or even the Bluetooth standard

take advantage of 2.4 gigahertz frequencies.

This means that we could have frequency conflicts when

trying to communicate using all of these devices

simultaneously in one single area.

It's also difficult to find 802.11b networks that might

still be operating.

And if you do run into an 802.11b network,

it's probably because you're upgrading it to a newer

version.

One of the first upgrades available to these 802.11b

networks was the standard for 802.11g.

This was released in the June 2003 time frame.

And just like 802.11b, 802.11g also operates in the 2.4

gigahertz range.

The reason that this was such a useful upgrade for folks

running 802.11b was that we increased the speed on the g

standard to 54 megabits per second,

which is about the same as we found with 802.11a.

This 802.11b g standard is backwards compatible with the b

standard.

That means that we could upgrade our access point to the 802.11g

and still continue to use our b devices on the same network.

And although 802.11g operates at higher speeds,

it still suffers from the same frequency conflicts that we

have with the 802.11b because all of these devices will be

using 2.4 gigahertz frequencies.

In 2009, a new standard was released that effectively

upgraded 802.11a, b, and g to a new version of 802.11n.

As you probably noticed, it can be

confusing to keep track of all of these different letters

and numbers.

So instead of using the standard name of 802.11a or 802.11g,

we're now referring to these standards as Wi-Fi standards.

So 802.11n can also be called Wi-Fi 4.

Technically speaking, 802.11a, b,

and g could also be called Wi-Fi 1, 2, or 3.

But because those standards are so old and indeed

difficult to find implemented on anyone's networks these days,

we are starting with Wi-Fi 4 as the standards

for this numbering scheme.

Because 802.11n or Wi-Fi 4 is designed to upgrade 802.11a, b,

and g, this standard is able to operate at both five gigahertz

and 2.4 gigahertz simultaneously if your access point supports

that.

We also have more bandwidth available

for each individual channel.

We can have up to 40 megahertz channel widths.

And what this really means is we're

able to transfer much more data at the same time

over this network.

If you do have a wireless access point that's able to use those

40 megahertz channel widths and it has four antennas on it,

you can get a maximum theoretical throughput from

802.11n of 600 megabits per second,

which is obviously a large improvement over 802.11a, b,

or g.

This 802.11n standard also introduced a new form

of communication for wireless networks called MIMO

or Multiple Input Multiple Output.

This means the devices can transfer much more information

simultaneously between the end station and the access point.

In January of 2014, we introduced 802.11ac,

which we now refer to as Wi-Fi 5.

And this was another improvement over the previous standard

of 802.11n.

Wi-Fi 5 operates exclusively in the 5 gigahertz range.

So unlike 802.11n, there is no 2.4 gigahertz available

in Wi-Fi 5.

We can also use much more of that wireless spectrum

simultaneously because 802.11ac will support up to 160

megahertz of a channel bandwidth.

This translates into more channels

that can be used simultaneously and therefore

more data that can be transferred

over that wireless network simultaneously.

This standard also changes how information is transferred

over that wireless network.

We refer to this as signaling modulation.

And this also increased the amount

of data that was able to be transferred

at any particular time.

This newer 802.11ac standard, not only uses multiple input

multiple output but increases the capabilities of that MIMO

by adding multi-user MIMO.

So multiple users could be communicating

over multiple input and multiple output simultaneously.

This standard supports up to eight of those multi-user MIMO

streams, which translates into a maximum total throughput

of nearly seven gigabits per second for 802.11ac.

We mentioned earlier that 802.11ac operates only

in the five gigahertz band.

But if you look at access points that may be available to buy,

you'll see some of them say that they are 802.11ac access points

that operate at five gigahertz and 2.4 gigahertz.

In those cases, the communication that's occurring

at 2.4 gigahertz is actually using the 802.11n standard

and anything at five gigahertz is using the ac standard.

The upgrade to 802.11ac arrived in February of 2021 with

the 802.11ax standard or what we call the Wi-Fi 6 standard.

This is a standard that operates at either five gigahertz

frequencies or 2.4 gigahertz frequencies

and on some access points can use both of those

simultaneously.

The standard also supports many different channel widths.

So we can have bandwidth of 20, 40, 80, and 160 megahertz

for people communicating on that wireless network.

If we look at the standards for 802.11ax,

we can get a total throughput per channel of about 1.2

gigabits per second.

This is a relatively small increase in throughput

when you compare it to other improvements in the standards

through the years.

But there is a difference in how this particular version was

designed.

802.11ax was designed to solve some of the problems we have

with using these wireless networks in areas where there

are large number of people.

So if you're at a sporting event or a trade show,

you may find it difficult sometimes

to communicate over these wireless networks.

With 802.11ax, we introduced a new form of communicating

called orthogonal frequency division multiple access

or OFDMA.

This takes a type of communication

that we've used for some time on our cellular networks

and brings it into the world of 802.11.

This allows us to put 802.11ax networks in places with large

numbers of people and be able to communicate without a huge loss

in efficiency over those wireless networks.

So here's the summary of these different standards.

802.11a operated on five gigahertz frequencies and did

not have MIMO support.

Its maximum theoretical throughput per stream

was 54 megabits per second.

And in the case of 802.11a, we only had one stream to work

with.

So we had a maximum throughput of 54 megabits per second.

802.11b operated in the 2.4 gigahertz range and it operated

at a maximum throughput at 11 megabits per second.

As the upgrade to 802.11b, 802.11g also operated at 2.4

gigahertz and had a maximum throughput of 54 megabits per

second.

If you run into an 802.11n network,

you can operate it either five or 2.4 gigahertz frequency

ranges and can use up to four separate streams of multiple

input and multiple output.

This gives us a total throughput per stream

of 150 megabits per second or a maximum throughput of 600

megabits per second overall.

802.11ac is a five gigahertz technology only.

It supports eight downloadable streams

of multi-user, multi input, multi output at 867 megabits

per second for each stream, making

a total theoretical throughput maximum

of 6.9 gigabits per second.

And 802.11ax operates at both five gigahertz and 2.4

gigahertz.

It also supports eight streams, but the multi-user MIMO in ax

supports a download and upload streams simultaneously.

That gives us a maximum theoretical throughput

per stream of 1.2 gigabits per second

and a maximum theoretical throughput of all

streams at 9.6 gigabits per second.

If you purchase an access point, bring it home, and plug it in,

you'll probably get a range of about 40 to 50 meters

if you're using the built in antennas.

If you're working in a corporate environment

and you want to connect two buildings together with 802.11,

then obviously that type of antenna is not going to work.

Instead you'll need some fixed directional antennas

and you may need to increase the overall signal

strength of the 802.11 signal.

In our offices and homes, we have

signals that might be bouncing or be absorbed

by the things around us.

When we're sending a signal between buildings,

there's usually not much in the way that would cause the signal

to bounce or be absorbed.

We would use very directional antennas like this Yagi antenna

to be able to have a very focused point to point

connection between an antenna on one building and the antenna

on the other building.

If you're planning to set up a long range fixed wireless

network, make sure you look at the rules

and regulations in your area.

Wireless networks have their own complexities

associated with them.

And when you layer on local and federal rules and regulations

regarding wireless communication,

it provides some additional challenges

to the implementation.

If you're using a wireless service that's

transmitting to your home or you're

trying to connect different wireless

services between buildings, you may

want to look to see what frequencies

are available to use.

You may have 2.4 and five gigahertz frequencies

available natively in the standard,

but there may be other frequencies available

that you can apply for which might provide you

some advantages over using the busier 2.4

gigahertz or five gigahertz frequencies.

You'll need to check with the 802.11 standards

and see what options might be available for the type

of network that you're installing.

Not only are there rules and regulations

about what frequencies you can use and where you can use them,

there are also regulations about how much of this signal

can be sent.

There are different regulations on whether these signals will

be inside of the building or outside of the building,

so make sure you know all of the differences

when you're installing the network.

And ultimately, you'll need to install an antenna outside

if you're receiving a signal from a service provider

or you're connecting two buildings together.

Installing antennas outside have their own set

of safety requirements not only in where

you install the antenna and that it's not near any power source,

but you also have to make sure that the antenna is protected

in case it happens to be hit by lightning.

In many cases, it might make more sense

to bring in a third party who has

an expertise in installing these types

of external or outdoor networks.

Another wireless technology that's widely used

is RFID or Radio Frequency Identification.

If you have an access badge that unlocks the door by holding it

up to a sensor, it's probably using

RFID inside of that badge.

If you're in manufacturing and you have an assembly line

or you need to keep track of inventory,

then you will extensively use RFID.

And we even use RFID at home to keep track of our pets.

So if we happen to lose that pet, they can easily be scanned

and that identification information

will be tied back to you so that your pet can be returned.

This is one type of RFID tag.

You can see this one is designed to be cylindrical.

And you can see how small it is because it's

next to this grain of rice.

If you have an RFID tag inside of your access badge,

then it's probably a flat one like this where the antenna is

around the outside and the RFID chip is right in the middle.

As you can see in these pictures,

there's often no battery inside of these RFID tags.

Instead this uses radar technology.

As we send signals out, that signal

is being captured by the antenna that

is converted to power added to the chip that effectively

powers and allows this device to transmit back.

Although this is one way to communicate via RFID,

there are other RFID tags that do have a power source.

We refer to those as active or powered RFID.

We've extended the use of RFID into our mobile phones

and our smartwatches through the use of NFC.

This is Near Field Communication and it's

a way for our mobile devices to be

able to have two way conversations

with other devices that we might use.

For example, we might be checking out at a store

and we can use our phone or our smartwatch

to pay for those goods because we've associated our credit

card with the NFC technology that's in our devices.

You might also see NFC used if you need

to pair two Bluetooth devices.

And because we often carry our phones

and our smartwatches with us, we can

use NFC to act as an access card so

that we can use our phone to unlock a door instead

of a separate card.