What’s the difference between all of the 802.11 standards?

This is a quick summary of all of the wireless-data 802.11 standards (”Wi-Fi”) that are currently being created. These all use Infrared radio-frequencies to transfer data wirelessly, but there are a lot of different ”flavors” of the 802.11 standard. Not all of them are concerned with speed. Each flavor has it’s own letter after the 802.11 number.

The official site for all of these standards can be found on the IEEE 802 website at www.ieee802.org/11

To jump directly to each description, click:

- Note about bandwidths.

- Common Wi-Fi related terms.

- What does ”802” mean?

- 802.11 WG

- 802.11

- 802.11a

- 802.11b

- 802.11c

- 802.11d

- 802.11e

- 802.11f

- 802.11g

- 802.11h

- 802.11i

- 802.11j

- 802.11k

- 802.11l

- 802.11m

- 802.11n

- 802.11o

- 802.11p

- 802.11q

- 802.11r

- 802.11s

- 802.11t

- 802.11u

- 802.11v

- What happens when we run out of letters in the alphabet?

- Other wireless standards.

- A note about TCP/IP.

Note about bandwidths

Keep in mind that all data bandwidth, whether wireless or wired, is measured in Megabits Per Second (Mbps), not Megabytes per second (MBps). The difference is indicated by whether or not the ”b” in the initials is capitalized. A little ”b” indicates bits, and a big ”B” indicates bytes. This rule about initials is not always followed consistenly, but the concept is consistent. Networks always measure data-transfers in bits, not bytes.

For example, data-transfers betwen 2 hard-disks connected to a computer are usually measured in Megabytes per second. This is because all computer-files are measured in bytes so the disk-to-disk transfers are also measured this way. But data-transfers between 2 computers on a network are measured in Megabits. Network devices like routers and switches don’t care that 8 bits equals 1 byte, they only care about how many bits are passing through them. They’re basically just bean-counters.

So when you hear that a network has a bandwidth of ”10 Meg” (10Mbps), this means that it can transfer a 1.2 Megabyte (MB) file in one second.

(10 Megabits ÷ 8 bits = 1.2 Megabytes)

As a comparison, keep in mind that the average home Ethernet LAN has a speed of either 10 or 100 Megabits per second. Most DSL or Cable-modem lines offer maximum speeds of around 3 Megabits per second. So the LAN is almost always faster than the WAN.

Common Terms:

Wi-Fi

This is simply the marketing term for all 802.11-related wireless networks. It stands for ”Wireless Fidelity”, a reference to Hi-Fi stereos, and the high-quality sound they produce.

There is an organization called ”The Wi-Fi Alliance” that officially certifies equipment from different vendors as following the standard Wi-Fi rules and will work with each other. If something is stamped as approved by this group, you can sleep easily at night.

Wi-Max

This is the marketing term for the newer 802.16 wireless standards (also called ”HiperMAN”) being developed, which define long-range wireless networks. This doesn’t yet exist in any commercial products, as of January, 2005. The range will be around 50 kilometers (31 miles), it should provide bandwidths up to 70 Mbps, and will use a radio spectrum somewhere within 2 – 11 GHz, as well as 10-66GHz. It will most likely be used by ISP’s for wireless service to customers, as a broadband alternative to DSL or Cable-Modems.

AP
AP stands for ”Access Point”

This is a common term used with Wi-Fi devices. It simply refers to the box with the antenna, the ”point” that is offering ”access” to the Wi-Fi network.

AP’s are often integrated into routers, so you can use one box to connect to a DSL or Cable-Modem line and create a wireless LAN. But AP’s are also sold separately as separate hardware, in which case you’ll still need a router to connect to your ISP link.

Router

Many consumer AP’s come with routers built in to them, but a router is different from an AP, and can be bought separately. Routers segment networks and control how traffic is ”routed” from one network to another. This is different from a switch or a hub, which are usually used to extend a single network, providing more ports for more devices on that single network. A router breaks up a network into several distinct networks. So a router built into an AP forms the boundary between your local LAN and the Internet connection. If your AP is set up correctly, but the router isn’t, traffic won’t get past the router. Some AP’s are referred to as ”routers”, but this usually just means that the box has an AP and a router both built in to it.

Ad-Hoc Mode

This is Wi-Fi just between 2 computers. Used for transferring files from computer to computer, as opposed to connecting to a common Access Point for network access. Don’t use this mode if you want Internet access.

Infrastructure Mode
This is Wi-Fi to an Access Point: where you have one Access Point and several clients. Use this mode if you want Internet access.

SSID
SSID stands for”Service Set Identifier”.
This is just the name of the Access Point that provides the signal. This is any name you choose for the box, such as ”Fred’s Linksys” or ”Home Router”. If there is more than one Access Point within range you’ll see multiple SSIDs listed when you set up your Wi-Fi connection. You need to select at least one in order to connect.

WEP
WEP stands for ”Wired Equivaent Privacy”.

This is a security feature supported by most Wi-Fi Access Points, which require that you log on to the Wi-Fi network with an encrypted password. However, this feature is usually turned off on most Access Points by default, requiring you to choose to turn it on. This is because it requires some extra work to set up on the client side, and it’s famously easy to break into. Other, better security solutions are being worked on to replace WEP eventually.

LAN, WAN, MAN, WRAN, PAN, WPAN, WLAN, SWAN...
There’s no concept simple enough that it won’t eventually be made confusing with an acronymn. These acronyms are used a lot in the press, but they all refer to simple networking ideas. Some of the more common ones are:

o LAN
Local Area Network (Such as Ethernet)

o WAN
Wide Area Network (DSL, Cable-Modems, T1’s)

o MAN
Metropolitan Area Network (WANs within a city)

o WRAN
Wireless Regional Area Network (Bigger than a MAN, but smaller than a WAN...)

o PAN
Personal Area Network (Wireless keyboards and mice)

o WPAN
Wireless PAN (Another name for the above)

o WLAN
Wireless LAN (Another term for Wi-Fi stuff)

o SWAN
Switched WAN (Switches that don’t use wires)

There are many more, with more created every few months, but they all like to end with the letters ”AN”...

HiperLAN
”HIPER” stands for ”High Performance Radio”.

This is a different standard for wireless data networks developed in Europe, by the European Telecommunications Standards Institute (”ETSI”). It’s basically a competing set of standards for doing the same thing as 802.11, but since European countries use some of the same frequencies as 802.11 for different things, a different set of standards has beeen developed.

There are 2 versions of HiperLAN:

- HiperLAN/1 Uses the 5GHz frequency to support bandwidths of 20Mbps.

- HiperLAN/2 Uses the 5GHz frequency to support bandwidths of 54Mbps.

There are efforts under-way to allow 802.11 networks to interact with HiperLAN networks, since America and Europe need to learn how to play better together.

What does ”802” mean?

This is the name of the group of committees within IEEE that defines standards for data networking. IEEE is a much larger group that spends time defining international standards for anything having to do with electronics. It was founded back in 1884 to create standards for electrical power and radio, and has evolved since then. The 802 sub-group was created in 1980 to focus on networking issues.

Why does it have such a dull name? It is named ”802” because the group was created in February, 1980: ”80” for 1980, and ”2” for the second month, February, which is probably the dullest reason for the name of a committee ever invented.... (”Bluetooth” is much more creative).

Each standard begins with the numbers 802, followed by a dot-something. Letters that follow the numbers deal with modifications to the standard. So 802.11 deals with wireless data networks, and 802.11b deals with a modification to that standard. Any other number besides 11 deals with other non-wireless stuff.

If you’re interested, you can find a list of all of the 802 networking standards here.

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802.11 WG

This isn’t actually a standard, but refers to the Working Group within the IEEE committees that work on expanding the original 802.11 standard. Each letter that comes after 802.11 refers to a different task-group that’s working on an addition to this standard.

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802.11

- First released in 1997.

- Bandwidth: 1 – 2 Mbps.

- Frequency: 2.4GHz

- Range: 100 Meters (approx. 300 feet)

- It uses one of two radio techniques to transfer data over radio signals:

- FSSS (”Frequence-Hopping Spread Spectrum”)

- DSSS (”Direct-Sequence Spread Spectrum”). This is the method used by most subsequent 802.11 standards.

- This is the original IEEE standard for wireless data networks. There is no letter after it.

- It’s now often called ”802.11 legacy”
- The original 802.11 was based on 802.3, the standard for wired Ethernet, which is why it was originally called ”Wireless Ethernet”.

Pros and Cons:
This is an old standard, and is too slow for most general use today. It still exists in some legacy environments, but there’s little reason to use this standard today, with all of the faster and more common flavors of 802.11 available now.

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802.11a

- First released in 2000.
- Bandwidth: 6 – 54 Mbps

- Frequency: 5.15 - 5.35GHz
- Range: 50 Meters (approx. 150 feet)

- Realistically, this distance is only ever achieved outside, with no
obstruction. Indoors, the usual distance is about half that, 75 feet.

- It uses a different radio technique for transfering data wirelessly, called OFDM
(”Orthogonal Frequency Division Multiplexing”)

- Also called ”Wi-Fi5” (due to its use of the 5GHz frequency)

- This was the second revision of 802.11 to become commerically available,
around 2000, The second revision, 802.11b was actually finished first, and
became available in commerical products before 802.11a was. This is the main
reason why there are fewer products that use ”.a” instead of ”.b”.

Pros:

- This version of 802.11 is faster than ”.b”, with speeds up to 54Mbps, depending on how close you are to the Access Point.

- Since it uses a frequency of 5GHz, there is less chance of interference with other common wireless devices, like cordless telephones, or radiation from microwave ovens.

Cons:

- The range of ”.a” is less than ”.b”, about a third of the range. So you get faster bandwidth, but less range.

- Devices that use 802.11a usually cost more than those that use 802.11b.

- This version of 802.11a is less common than 802.11b. The 2 standards were worked on at the same time, but ”.a” became available in commerical products after ”.b” was, and they are not compatible with each other, since they use 2 different frequencies. The main benefit of this version of 802.11 is that it uses the 5GHz frequency, so you get less interference. But you have to deal with shorter range and more expensive equipment.

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802.11b

- First released in late 1999.

- Bandwidth: 11Mbps

- This in theory. Most of the time you’ll see 4-6 Mbps, due to how
close you are to the Access Point, and any interference in the area.

- Frequency: 2.4GHz
- Range: 100 Meters (approx. 300 feet)

- Realistically, this distance is only ever achieved outside, with no
obstruction. Indoors, the usual distance is about half that, 150 feet.

- It uses a radio technique for transfering data wirelessly called "High Rate DSSS” (Direct
Sequence Spread Spectrum). It also uses CCK (”Complementary Code Keying”), which
is a modulation technique that uses the radio spectrum efficiently.

- Also called ”802.11 High Rate”.

- There is an extension to this version of 802.11, called 802.11b+, which pushes the
bandwidth up to 22Mpbs. But this is not supported by most Wi-Fi vendors.

- There are devices that support ”802.11a/b”, which basically are 2 devices in one: the 2
standards are not compatible with each other, so a/b means that the device contains the
hardware needed to support both standards. These are usually more expensive.

Pros:

- This is, by far, the most common version of 802.11 in use today. Almost all public access-points, like airports, hotels, and coffee-shops, use the ”.b” version of 802.11. So this is the safest standard to use for most consumer products.

- 802.11b devices are usually cheaper than 802.11a devices.

Cons:

- The 2.4 GHz frequency used by ”.b” is ”unregulated”, meaning it’s also used by other common consumer items, like cordless telephones and the radiation from microwave ovens. If you use an 802.11b device next to one of these things you’ll get interference and may get disconnected from the network. So place you items wisely. (Most Wi-Fi routers let you select from 11 different ”channels”, which bump the frequency up or down a bit around the 2GHz range, which will sometimes reduce the amount of interference.)

- This is a limitation with all Wi-Fi devices, but the signal can be blocked or reduced by walls that contain lead pipes, or exterior walls with metal siding. So you should place the AP in an area free of interference. The signal can travel through walls, so it doesn’t need to be line-of-site, but anything metal in the area, like pipes or stair-railings, can cause weird signal-reductions.

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802.11c
- Also called "Bridge Operation Procedures". This defines how to ”bridge” 2 or more
Wi-Fi Access Points together, where a second Access Point receives and re-generates
the signal from the primary Access Point, in order to extend the signal’s range.

- This standard is used in most 802.11 devices, but it’s usually invisible to the user, so
it’s generally not of much interest to the consumer.

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802.11d
- First released in 2001.

- Also called "Global Harmonization".

- This standard deals with making 802.11 work in different countries. 802.11 has been
ratified in the US, Europe, and Japan, but other countries often have different standards.
Also, some frequencies, like 5GHz, are used for other things in other countries so
this flavor of 802.11 works to make sure interference doesn’t become a problem.

- This is also not a standard that’s relevant to most consumers, but it makes the world a

happier place.

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802.11e

- First released in 2002
- Also called "MAC Enhancements for QoS".

- QoS refers to ”Quality of Service” and addresses how to prioritize one kind of traffic
over another. Such as, a VoIP telephone using 802.11 has to be given priority on the
network over email, since voice delays can cause serious ”jitter” in the call. This
version of 802.11 creates ways to do this, using the MAC (”Medium Access Layer”)

to mark certain traffic as more important than others.

- Without this ability, network traffic is ”best effort”, meaning your mileage may vary.

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802.11f

- First released in 2003

- Also called "Inter Access Point Protocol" (IAPP)

- This flavor of 802.11 deals with ”roaming”, from one Wi-Fi Access Point to another
without getting disconnected from the network.

- Roaming has been supported by vendors prior to the creation of this standard, but

they’re proprietary: different vendors don’t play well when romaing. So if you bought

equipment from different vendors, roaming would usually break when romaing from

one Acess Point to another. So you can use roaming without 802.11f, but you need to

buy all your equipment from the same vendor.

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802.11g

- First relased in 2003

- Bandwidth: 54Mbps

- This in theory. Most of the time you’ll see around 25 Mbps, due to how
close you are to the Access Point, and any interference in the area.

- Frequency: 2.4GHz
- Range: 100 Meters (approx. 300 feet)

- Realistically, this distance is only ever achieved outside, with no
obstruction. Indoors, the usual distance is about half that, 150 feet.

- It uses the radio technique OFDM (”Orthogonal Frequency Division Multiplexing”) for

transfering data wirelessly.

- Also called "Higher rate extension to 2.4GHz band"

- There is an extension to this version of 802.11, called Super G, which pushes the
bandwidth up to 108Mpbs, using ”channel bonding”. But this is not yet supported by

most Wi-Fi vendors.

- There are devices that support ”802.11b/g”, which simply means that both standards are
supported. Since both standards use the same frequency, 2.4GHz, they both have the
same range and can be easily supported by one Access Point.

Pros:

- This version of 802.11 is basically an upgrade of 802.11b, the most common flavor of Wi-Fi used today. So it’s fully backwards-compatible with existing equipment, using the same 2.4Ghz frequency, but it’s much faster: 54Mbps compared to 11Mpbs.

- Since alomst all 802.11g AP’s and routers sold today support existing ”.b” clients, installing a ”.g” Access Point will mean that all of your existing hardware will still work.

- Because it’s backwards compatible, you can use ”.g” equipment like routers to offer faster speeds to client hardware, but if you’re still using ”.b” stuff in your computer everything will still work. You’ll just still be running at the ”slower” speed of 11Mbps. You need to buy a new Wi-Fi card for your computer to benefit from the higher speed.

Cons:

- 802.11g usually requires somewhat bigger hardware. Such as, most 802.11b cards are made with PCMCIA cards, but some 802.11g cards are bigger than this, requiring the use of non-PCMCIA slots or installation inside of your computer. For instance, as of 2004, Apple’s new computers are all now 802.11g capable, meaning that their old 802.11b PCMICA cards won’t work in their newer computers. So check to make sure you can use the new cards in your existing computer.

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802.11h
- First released in 2003

- Bandwidth: 6 – 54 Mbps
- Frequency: 5GHz
- Range: 50 Meters (approx. 150 feet)

- Also called "Spectrum Managed 802.11a"

- This version of 802.11 is basically a modified version of ”.a”, with basically the same
range and bandwidth. It exists due to how the 5GHz frequency is used in Europe. This

frequency is used by satellite communications in Europe, so using 802.11a Wi-Fi in this

environment would make European scientists very unpleasant. So this version was

developed to avoid this.

- It avoids the problem primarilly by using 2 radio techniques called DCS (”Dynamic

Channel Selection”) and TPC (”Transmit Power Control”) to use the same frequency

without causing problems.

- These are the same techniques used by another wireless data standard that has been
developed in Europe as a competitor to ”.a”, called ”HiperLAN/2” (not to be confused
with ”HiperMAN” which refers to the long-distance WiMax standard).

- If all goes well, and European scientists like what they see, 802.11h could eventually
replace 802.11a, since they’re both compatible with each other.

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802.11i
- Not yet released.

- Also called "MAC Enhancements for Enhanced Security"

- Wi-Fi is basically a wire that is ”wide open”. In a wired network you need access to the

physical wire if you want to spy on what traffic is passing by. But with Wi-Fi these
signals are much easier to intercept. Currently, Wi-Fi has not yet truly addressed this
problem aggressively.

There is a security feature called WEP (”Wired Equivaent Privacy”) that most Wi-Fi

Access Points support. But this is notoriously weak and easy to crack, since WEP
passwords are ”static” with low levels of encryption. So 802.11i is a work in progress

to try and create a much stronger security standard for wireless data.

- There is a newer security scheme called WPA (”Wi-Fi Protected Access”) which is
a bit more robust than WEP, but it will likely not be the final recommended standard
for wireless security.

- It will most likely achieve this by using another 802 standard, 802.1x, which does port-
based MAC authentication. It will also probably use AES (”Advanced Encryption
Standard”) to better encrypt passwords as they fly through the air.

- Due to the usual requirements of dedicated hardware to speed the encryption and
decryption of passwords, using the ”.i” security standard will probably require new
hardware.

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802.11j
- Not yet released.
- Bandwidth: 6 – 54 Mbps
- Frequency: 4.9 - 5GHz
- Range: 50 Meters (approx. 150 feet)

- It uses the radio technique OFDM (”Orthogonal Frequency Division Multiplexing”) for

transfering data wirelessly.

- This is a version of 802.11a meant for Japan, to accomodate their regulations.

- It will add some new channels in the 4.9 – 5GHz frequency range, modify the output
power, and reduce ”spurious emission” levels, all of which are legally required in order
to sell Wi-Fi in Japan. It will also enable it to work alongside HiperLAN/2 devices,
Europe’s competitor to the 802.11 standards.

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802.11k
- Not yet released

- This is a project designed to make the process of Wi-Fi Channel Selection more efficient.
When roaming, Wi-Fi clients usually connect to the Access Point with the strongest
signal. Even if that AP is over-utilized, this AP is still chosen due to the signal strength,

even if the load will cause a slower connection. 802.11k would allow a connection to be
made to an AP with a weaker signal, if that load is lighter, resulting in an overall
better connection.

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802.11l
- This standard does not exist. The letter ”L” was skipped because it looks too much like

the letter ”I”. This is probably the only time a standards committee ever made an attempt
to avoid confusion instead of encouraging it....

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802.11m
- In progress.
- Also called "802.11 Housekeeping" and "802.11 Cleanup".

- This is an ongoing project to maintain, edit, and clarify all documents related to all 802.11
standards. Basically an effort to be tidy.

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802.11n
- Not yet released.

- Bandwidth: 100 - 250Mbps
- Frequency: Not yet determined. Possibly 5GHz.
- Range: 50 Meters (approx. 150 feet)

- The faster speeds are partly due to a new technology called MIMO (”Multipe In Multiple
Out”) which creates several parallel channels for incoming and outbound data, and usually
requires several additional antennas on the hardware.

- Although ”.n” is not yet released, as of January, 2005, several vendors are selling 802.11
products that claim to be ”Pre-N”. This means that they are betting on one of several
versions of the ”.n” proposals currently competing for approval, and deliver the speed and
frequency that the ”.n” standard promises.

This is risky though, since the final standard may well incorporate several different

proposals and produce a final version that is different from anything being sold today. Some

vendors claim to support upgrading to the final standard when it’s released, but similar past

gambles have required that customers buy entirely new hardware to support the final
standard.

So it depends on how patient you are as a customer.

Pros:

- This version of 802.11 is a big jump in bandwidth over any previous version: at least 100Mbps compared to 54Mbps, the fastest currently available Wi-Fi, used by ”.g”.

- This version of 802.11 uses the same frequency as ”.a”, 5GHz. This is the ”safer” frequency to use, as opposed to 2.4GHz as used by ”.b” and ”.g”, so there is less chance of interference.

Cons:

- Because this version of 802.11 uses a different frequency than ”.b” and ”.g”, this means that its’ not backwards compatible with most of the Wi-Fi current installations at most airports, hotels, and coffee-shops. You get a lot more speed with this version, but you have to buy all new hardware. There may well be hardware that will be sold as something like ”802.11b/n” but this will mean that it contains double the hardware, in order to support both standards, so it will likely cost more. So this version will be most useful where the higher bandwidth is truly needed.

Keep in mind that most DSL lines and Cable-Modems are typically only 3Mpbs, so the 100Mpbs bandwidth available with ”.n” will be used only devices on your local LAN, not across the Internet. (Unless you have an ISP connection that is really as fast, or faster, than 100Mbps).

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802.11o
- Not yet released
- Also called ”The Fast Roaming Study Group”

- This standard is a spin-off of the 802.1i study-group, since it deals specifically with
issues related to using VoIP over 802.11 wireless networks. Specifically, it deals with
”handoffs” when roaming from one wireless Access Point to another, while using the
WPA security scheme.

Using WPA, roaming from one Access Point to another will create delays of
70 milliseconds to over 1 second, due to the need for the wireless client to re-authenticate
through the new Access Point. This is OK for most data applications, but it is a problem
when using a VoIP telephone. The goal is to reduce this delay to 50 milliseconds or less.

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802.11p
- Not yet released
- Bandwidth: 6Mbps
- Frequency: 5.9GHz.
- Range: 300 Meters (approx. 1,000 feet)

- Also called WAVE (”Wireless Access for the Vehicular Environment”).
- Also called DSRC (”Dedicated Short Range Communications”).

- This proposed standard addresses using Wi-Wi in moving vehicles, like cars or ambulances.
It deals with issues like hand-offs between Access Points as well as communicating in
”Ad-Hoc” mode, vehicle-to-vehicle.

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802.11q
- Not yet released.
- Also called ”VLAN Management”

- This is a proposed standard for segmenting wireless networks into multiple Virtual LANs”.
Currently, Wi-Fi networks are single ”flat” networks, with segmentation required on
routers or switches behind the Access Point. This standard would allow that within the
Access Point.

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802.11r
- Not yet released.
- Also called ("Fast Roaming")

- This is a spin-off from the 802.11f task-force, which deals with roaming from one
Access-Point to another. This newer flavor of 802.11 deals speficially with using wireless
VoIP telephones when roaming between Access Points. Currently, when romaing between
Access Points a wireless client needs to request new IP address info and re-authenticate
onto the network, which can take up to several seconds, which makes most phone calls
useless. This task force’s goal is to reduce this re-connection process to 20 milliseconds.

- Some vendors currently sell 802.11 equipment that claims to support Fast Romaing for
wireless VoIP clients, but these use proprietary technology, specific to each company.
They almost all use the notoriously insecure WEP security scheme to keep the
re-authenitcation times below 20 milliseconds, so once the 802.11r standard is decided
upon, customers of these vendors will most likely need to upgrade to new hardware.

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802.11s
- Not yet released.
- Also called ”ESS Mesh Networking” (ESS stands for ”Extended Service Set”)

- A ”Mesh” network is simply a network with multiple Access Points. Such as, a home
network that has one Access Point in each room, all creating one wireless network, is

meshed, eliminating any ”dead spots” in the house. So if one antenna fails, or interference
appears in a room (like someone turning on a microwave oven) the signal would still be
available through another, redundant antenna in the mesh.

- This task force is working on defining how this will work, and how such a meshed
network would he ”self-healing” in the event of an Access Point dropping off the net.
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802.11t
- Not yet released.

- Also called WPP (“Wireless Performance Prediction”)

- This is a project whose aim is to create some standard methods for testing Wi-Fi networks
and producing metrics that everyone can agree on. Their official mission statement is to
create a “Recommended Practice for the Evaluation of 802.11 Wireless Performance”.
Currently, testing Wi-Fi networks and collecting performance metrics is a bit of a loosely

defined process. This project is attempting to formalize that process.

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802.11u
- Not yet released.
- Also called WIEN (”Wireless Internetworking with External Networks”)
It’s not named after the German name for the city of Vienna....

- This is a project whose goal is to allow 802.11 networks to interact with other non-802
wireless networks, such as Cellular networks.
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802.11v
- Not yet released.
-Also called ”Wireless Network Management”

- This is a project to create a standard approach to centrally manage Wi-Fi Access Points
in a way that all vendors will agree on. Currently, all remote management and
configuration tools for Wi-Fi hardware is specific to each vendor, most of which are
are based on SNMPv3. But since SNMP requires that an IP connection already exists
prior to configuration, this makes it difficult to remotely manage an Access Point prior
to getting TCP/IP to work. This project’s goal is to resolve this and related issues.

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That’s the end of the 802.11 sub-standards, as of January 2005. That leaves 3 letters left for future additions: .w, .y, and .z.

The extension ”.x” probably won’t be used, since the term ”802.11x” is usually used to refer to all of the 802.11 standards. Since 802.11 by itself, without any letter after it, is the actual name of the original standard, the .x is added to it when referring to all of the addtions since 802.11 was first released in 1997.

What happens when we run out of letters in the alphabet?

This is a problem that apparently hasn’t been considered by the 802.11 committees yet. It’s been suggested that, if 802.11 exceeds 26 revisions, and therefore runs out of letters in the alphabet, that they would need to start doubling up letters, such as using 802.11aa or 802.11bb. But this would probably just be more confusing.

The ”11” in 802.11 can’t change since this covers the entire collection of wireless data standards. You can’t change it to the next number up, 12, or the next number down, 9. These already describe other networking standards. For instance, 802.9 describes the standards for so-called ”Isochronous Ethernet”, and 802.12 describes the standards for ”Demand Priority Networks”.

Also, the ”802” can’t change either, since this is the name of the IEEE group of committees devoted to all data networking standards.

We may need to resort to using something other than letters or numbers.

Emoticons might work, such as 802.11 ;-) or 802.11 :-0

Other wireless standards:

There are other ways to transfter data wirelessly, besides Wi-Fi. Most of these are slower:

- 900 MHz
This is the frequency used by most consumer wireless products, like wireless baby-monitors and some earlier cordless phones.

It is also used for pre-802.11 wireless LAN connections, in which you could extend a LAN between buildings by installing an antenna on each roof and aim them at each other, producing 2 - 10Mbps of bandwidth across the link. These kinds of devices actually use a wide variety of frequencies, but most of them use 900MHz.

- 3G
3G stands for “Third-Generation Wireless”, and usually refers to upcoming wireless data capabilities of cell phones. It is sometimes used along with the term UMTS (”Universal Mobile Telecommunications Service”) which is a specific approach to delivering these third-generation capabilities. Just to add to the confusion, UMTS is sometimes also called ”IMT-2000”.

The first generation of wireless (“1G”) lasted from the 1970’s through the 1980’s, and consisted of the original mobile telephones, which still used analog voice-signaling and worked a lot like amateur-radios.

The second generation of wireless (“2G”) began in the 1990’s and is still in use today, as of January 2005. It uses digital voice-encoding techniques, instead of analog, with names like “CDMA” (Code Division Multipe Access), “TDMA” (Time Division Multiple Access), and “GSM” (Global System of Mobile Communication). With the advent of the third-generation (“3G”) on the horizon, this later stage of the second-generation of cellular wireless is sometimes called “2.5G” (for “Second-and-a-Half Generation”).

When 3G finally sees the light of day it should include these capabilities:

o Integrated Voice, Video, and Data features.

o 2Mbps bandwidth, to support these new features.

o It will probably use the 2GHz frequency for transmission.

o Better roaming capabilities across the US, Europe, and Japan.

4G is the term used to describe future planned features of cellular networking following 3G. The goal for 4G is to provide cellular data rates up at around 20Mbps, as well as real-time multimedia tools like full-motion video-phones and GPS-related tools. But don’t hold your breath: since 3G is still in the hype phase, as of January 2005, anyone talking about 4G is beyond hype.

- Bluetooth
This is the name for ”short-distance” wireless technology used with wireless keyboards, mice, and headsets. It is sometimes referred to as a PAN (”Personal Area Network”) or a WPAN (”Wireless PAN”).

It’s not meant as a replacement for Wi-Fi, since it’s focused on short distances: 10 meters (around 30 feet), as opposed to the much longer range of Wi-Fi. Bluetooth is useful for replacing the wires between a keyboard and your computer, or an ear-piece and the cellphone in your pocket.

Bluetooth uses very low power, since the desired range is quite low. But newer high-powered Bluetooth devices may soon appear, pushing the range up to 100 meters (around 300 feet) making it comparable to Wi-Fi’s range. So perhaps then you’d be able to sit with your keyboard 300 feet away from your computer’s monitor, which will give you an excuse to replace it with a 60-inch plasma-screen so you can see what you’re doing from that distance.

o Useless Trivia:
Why is it called Bluetooth? The goal of technology is to unify all short-range wireless technologies into one, interoperable method. Therefore, it is named after a Danish viking named Harald Blåtand (Blåtand is Danish for ”Bluetooth”) who lived in the 10th century, and who unified Denmark and Norway into a single kingdom. He established Christianity as his new kingdom’s official religion, bringing his new country into ”fraternity” with the rest of Europe. So you might think of the Bluetooth technology as the Christendom of wireless data.

By the way, ”bluetooth” didn’t refer to his teeth, but refered to a dark complexion: Harald had very dark hair, which was unusual at the time for his fellow-pillaging Vikings.

The company Ericsson has even erected a modern runic-stone in Lund, Sweden, in memory of the jolly old Viking, in honor of their having used his name for their business. The enscription on the stone says, (translated from Swedish):

§ ”Ericsson Mobile Communications AB erected this stone to the memory of Harald Bluetooth who gave his name to a new wireless technology for mobile communication”.

(The Swedes can’t be accused of being ungrateful to their ancestors....)

- 802.15
This is the IEEE’s 802 standard applied to all PAN’s (”Personal Area Networks”), of which Bluetooth is one type. It’s actually based on Bluetooth, and is meant to be an industry standard for future wireless PAN technologies.

It’s somtimes referred to as UWB (”UltraWideBand”).

It is also sometimes called WiMedia, which is basically a marketing term for Wireless PANs (Is there no end to new acronyms.....?)

- RFD
RFD stands for ”Radio Frequency Device”. These are very short-range wireless devices, like proximity-badges: security-badges that are recognized when placed within a few inches of the reader, as opposed to ”swiping” it through the reader like a credit-card. They are also used in environments like hospitals and airports. They are mainly used to recognize security or ID credentials, not to transfer data.

A note about TCP/IP

An occasional source of confusion is the relationship between TCP/IP and Wi-Fi. The two terms are often used together, but they aren’t related in any way.

Think of Wi-Fi as equivalent to a wire, but a wireless wire. TCP/IP (often just called ”IP”) is one of many different networking protocols. Other networking protocols are Novell Netware, AppleTalk, DECnet, etc. Networking protocols run ”on top” of wired networks as well as wireless networks, but any protocol can run on pretty much any kind of network.

Sometimes a networking protocol is compared to a language, like English or Spanish, and networks themselves as telephone calls. You can speak either language over the telephone, it doesn’t matter. But in America you tend to hear English used most often over telephones.

When you set up a Wi-Fi network you will be running a particular protocol over it. Since IP is the protocol used over the Internet it’s therefore the most common protocol around today. It’s the default protocol used by all Windows PCs and Macs, so pretty much any Wi-Fi connection in use today uses IP as its protocol. But this is a choice, it’s not a technical requirement of Wi-Fi itself. It is technically possible to run any other standard networking protocol over Wi-Fi, if required. (Non-IP Wi-Fi isn’t yet supported by most vendors).

This is why Wi-Fi is sometimes referred to as a ”Layer 2” technology and TCP/IP is ”Layer 3”. (The actual electromagnetic wave-encoding would be ”Layer 1”). These ”Layers” go from 1 – 7, with the actual user-interaction, like Web-browsing, being considered Layer 7, and the inbetween Layers being magic.