Speaker 1: Get in touch with technology with tech Stuff from how
Speaker 1: stuff works dot com. Hey there, and welcome to tech Stuff.
Speaker 1: I'm your host, Jonathan Strickland. I'm an executive producer at
Speaker 1: how Stuff Works in I love all things tech, and
Speaker 1: one of the most pervasive modern technologies today is WiFi,
Speaker 1: which is fascinating since as a standard, it just had
Speaker 1: its twenty first birthday not long ago. The original WiFi
Speaker 1: standard was released in nine seven, but the development of
Speaker 1: WiFi stretches back further than that, and I thought it
Speaker 1: might be interesting to trace that history and get to
Speaker 1: know more about the tech that lets us set up
Speaker 1: a local coffee shop situation, you know, to catch up
Speaker 1: on emails. How, how did that come to pass, and
Speaker 1: how does it actually work? Well. Decades before there was
Speaker 1: a WiFi standard, there was a Lohan net. Back in
Speaker 1: the late nineteen sixties, computer scientists and students at the
Speaker 1: University of Hawaii. We're trying to come up with a
Speaker 1: way that would let students on the various Hawaiian islands
Speaker 1: communicate with the main frame computer on the Oahu campus
Speaker 1: at the university. Their work was concurrent with the work
Speaker 1: of BBN, a company that was working on our bonnet
Speaker 1: and our ponette, you may remember, was the predecessor to
Speaker 1: the Internet. The purpose of our ponet was to find
Speaker 1: out ways to connect remote computers together, remote computers that
Speaker 1: were working on different computer architectures, and have a way
Speaker 1: that they can meaningfully communicate with each other. Well, this
Speaker 1: was happening around the same time. Now, one thing the
Speaker 1: group wanted to do was take advantage of a special
Speaker 1: way to send data between computers called packet switching. M
Speaker 1: I T had developed packet switching back in nineteen sixty five,
Speaker 1: so it was still a relatively new technology when the
Speaker 1: folks over at the University of Why You decided to
Speaker 1: try and create their own Aloha net. So what exactly
Speaker 1: is packet switching and why is it so important and
Speaker 1: how networks send information? Well, let's say you want to
Speaker 1: transfer a large file from one computer to another, a
Speaker 1: really big one. Let's say that it's maybe several gigabytes
Speaker 1: in size, which today is a pretty big file. Back
Speaker 1: in the days of nine that would have been an
Speaker 1: unimaginably huge file. But let's stick with it. Now. Let's
Speaker 1: say you're trying to send that file over a network.
Speaker 1: The bandwidth of that network might limit how large a
Speaker 1: file you'd be able to send. In other words, your connections,
Speaker 1: your routers, your switches, your buses, if they have a
Speaker 1: limit on how much information can pass through at one time,
Speaker 1: that might mean that you can't send that file. It's
Speaker 1: just too big to fit through the pipes. If you
Speaker 1: want to have kind of a poor analogy, but a
Speaker 1: physical analogy, imagine that you have a very narrow road
Speaker 1: and you're driving a really wide truck, and you're really
Speaker 1: wide truck is actually too wide for the narrow road. Well,
Speaker 1: looks like you're gonna have to find another way to
Speaker 1: get your truck to the other side of that road.
Speaker 1: That's kind of what I'm talking about here. So packet
Speaker 1: switching was a way to make this more manageable, to
Speaker 1: allow files to transfer across a network in a way
Speaker 1: that did not overly stress the infrastructure. Essentially, packet switching
Speaker 1: works by dividing files up into chunks of data called packets.
Speaker 1: You can think of them as like envelopes that have
Speaker 1: letters inside of them, and each letter is part of
Speaker 1: a file that you're sending across the Internet. Packets contain
Speaker 1: a little extra information in them in addition to the
Speaker 1: file itself. That information includes data about the computer that
Speaker 1: was sending the file the computer that's supposed to receive
Speaker 1: the file, so kind of like the return address and
Speaker 1: the send address, those two things would be included, and
Speaker 1: also how that particular chunk of data fits in with
Speaker 1: the rest of the information that's being sent. So you
Speaker 1: can also think of it as sort of like instructions
Speaker 1: on how to put a puzzle back together. So if
Speaker 1: I go with the mail analogy, as in like postal mail,
Speaker 1: every single piece of information is a piece of a puzzle,
Speaker 1: and with that piece of a puzzle, I include a
Speaker 1: little bit of instructions about where that piece fits. I
Speaker 1: might say this piece is the bottom right corner of
Speaker 1: the puzzle, and then the envelope has the address that
Speaker 1: I'm sending from and the address I'm sending to. Well,
Speaker 1: that's kind of like a packet of data. In packet switching,
Speaker 1: you send these smaller, more manageable chunks of data across
Speaker 1: a network. The chunks may or may not follow the
Speaker 1: same pathway to get to their destination. They may not
Speaker 1: all go through the exact same nodes across the Internet.
Speaker 1: The neat thing is they can all split up and
Speaker 1: take different pathways, and typically you have duplicate packets journeying
Speaker 1: to the destination to help ensure that the full file
Speaker 1: arrives where it needs to go. Otherwise the file will
Speaker 1: be corrupt because it will be missing a piece of
Speaker 1: the puzzle. Once the packets get to the right computer,
Speaker 1: they get reassembled into whatever the original file was, whether
Speaker 1: it's a text file, an image video, whatever it might be.
Speaker 1: The team at the University of Hawaii wanted to use
Speaker 1: packet switching technology coupled with radio transmissions in order to
Speaker 1: send information from the main frame and to receive information
Speaker 1: from students across the island chain. They decided to create
Speaker 1: a system that would transmit information using radio signals that
Speaker 1: were in the ultra high frequency or UHF range. UHF,
Speaker 1: apart from being a hilarious weird Al Yankovic movie, is
Speaker 1: a range of radio signals that fall into the spectrum
Speaker 1: that at the low end is at three hundred mega
Speaker 1: hurts and at the upper end is at three giga hurts.
Speaker 1: Now it hurts is a unit that refers to one
Speaker 1: cycle per second. I've talked about this recently, but it's
Speaker 1: always good to go over this again. Now imagine that
Speaker 1: a radio wave is a long sign wave with smooth,
Speaker 1: even peaks and valleys, and they just repeat over and
Speaker 1: over and over again. Now, if you were to take
Speaker 1: an arbitrary point, such as the peak of the wave,
Speaker 1: and measure it to the next peak over, you would
Speaker 1: have one wavelength of that radio wave. Radio waves travel
Speaker 1: at the speed of light, regardless of wavelength, if it's
Speaker 1: a short wavelength or a long wavelength. So if you
Speaker 1: know how long a wavelength is for a radio wave,
Speaker 1: you know how many radio waves will pass a given
Speaker 1: point in space every second, because you already know the
Speaker 1: speed at which they will travel. A three hundred mega
Speaker 1: Hurts radio wave will have three hundred million waves pass
Speaker 1: through a given point in space per second. A three
Speaker 1: giga Hurts radio wave will have three billion radio waves
Speaker 1: pass that same point per second. The three gig Hurts
Speaker 1: waves clearly have to be smaller than the mega Hurts
Speaker 1: ones because they're all traveling at the same speed. So
Speaker 1: the only way you can cram more wavelengths past the
Speaker 1: point per second is by decreasing the wavelength. The radio
Speaker 1: spectrum as a whole, by the way, starts all the
Speaker 1: way down at three hurts meaning only three extremely long
Speaker 1: radio waves would pass a given point in space every second,
Speaker 1: and it goes all the way up to three terra hurts,
Speaker 1: which is equivalent to three thousand giga hurts or three
Speaker 1: thousand billion cycles per second. So while UHF stands for
Speaker 1: ultra high frequency, it's nowhere near the top of the spectrum.
Speaker 1: Aloha net relied on to such frequencies in the UHF range.
Speaker 1: One frequency was used for outgoing signals from the main
Speaker 1: frame to the other computers, so the main computer would
Speaker 1: send signals out over one frequency to students, but the
Speaker 1: other frequency was used by the other computers to send
Speaker 1: messages back to the main frame, so the students machines
Speaker 1: would use a different frequency. So you had kind of
Speaker 1: two channels in a way. You had the outgoing and
Speaker 1: the incoming. But this created a possible problem. There could
Speaker 1: come an instance in which more than one computer was
Speaker 1: trying to communicate with the main frame at the same time,
Speaker 1: and when that happened, the signals were said to quote
Speaker 1: unquote collide with one another. It's sort of like trying
Speaker 1: to have multiple people talk over a single radio channel.
Speaker 1: Only one person can speak at a time. If multiple
Speaker 1: people try it's just a mess. So alohan Net adopted
Speaker 1: a strategy in which the main frame would send out
Speaker 1: a received signal whenever an incoming message came in without
Speaker 1: a collision. It was essentially saying, I am confirming that
Speaker 1: I got your message, and that would tell the sending
Speaker 1: computer that the message got through, and if the sending
Speaker 1: computer did not get such a response, it would attempt
Speaker 1: to send the packets of data again at a randomly
Speaker 1: determined time interval. That random interval was meant to decrease
Speaker 1: the possibility that another collision would occur because obviously more
Speaker 1: than one computer is involved in this, and if both
Speaker 1: computers tried to send the exact same data packets at
Speaker 1: the same time intervals over and over again, you're just
Speaker 1: gonna keep getting collisions. This time, there would be the
Speaker 1: hope that there would be no collisions because you would
Speaker 1: have this somewhat random time interval that is spacing things
Speaker 1: out a little bit. Now. In its original configuration, alohan
Speaker 1: that was not terribly efficient. It had a throughput rate
Speaker 1: of just eighteen percent and most of the bandwidth went unused,
Speaker 1: and so the team needed to come up with a fix. First,
Speaker 1: they tried the old time sharing route. Time sharing is
Speaker 1: when you have several terminals connected to a centralized computer.
Speaker 1: The computer can only work on one set of instructions
Speaker 1: at a time, and so users have to wait a
Speaker 1: turn to access the computers processing power and memory and etcetera.
Speaker 1: But computers work really fast and so frequently it would
Speaker 1: feel like you were working on a mainframe in real
Speaker 1: time at the same time as everybody else, though in
Speaker 1: fact the computer is actually rushing to complete one set
Speaker 1: of instructions before starting on the next one. The problem
Speaker 1: with time sharing over radio network was that the computers
Speaker 1: had to follow a schedule of when they could send packets,
Speaker 1: so if it wasn't their time to send a packet,
Speaker 1: they had to wait and so and meant that there
Speaker 1: were wasted cycles since sometimes the computer had nothing to
Speaker 1: send and so those scheduled transmission times would go unused. However,
Speaker 1: this did increase the throughput rate for a Looha net,
Speaker 1: so it improved things a little bit. The team decided
Speaker 1: to try a different approach to improve the system further,
Speaker 1: and they designed instructions so that client machines, the ones
Speaker 1: that are sending request to the centralized computer, would monitor
Speaker 1: the traffic on the radio channel to determine when the
Speaker 1: channel was free. So essentially they're listening for the quiet spots,
Speaker 1: and then the client machine would send packets over that
Speaker 1: radio channel. The packets were actually smaller at this point,
Speaker 1: which would allow for more gaps between packets, and that
Speaker 1: would allow other computers to slip other packets in. So
Speaker 1: while the messages appear to be consistent and continuous, in
Speaker 1: fact it's a bunch of tiny little puzzle pieces, and
Speaker 1: occasionally there's enough of a gap for other puzzle pieces
Speaker 1: to sneak in, and the centralized computer would just sort
Speaker 1: everything based upon the meta information on the packets. This
Speaker 1: approach got the name Carrier Sense Multiple Access or c
Speaker 1: s m A. The system continued to monitor collisions as well,
Speaker 1: so it's full name was c s m A DASH
Speaker 1: c D or Carrier Since Multiple Access with Collision Detection.
Speaker 1: Now I've got more to say about the evolution toward WiFi,
Speaker 1: but before I go further, let's take a quick break
Speaker 1: to thank our sponsor Aloha. Nette was up and running
Speaker 1: by nineteen seventy one, but it would still be more
Speaker 1: than twenty years before we'd see the first WiFi standard
Speaker 1: get unveiled. He could be fourteen years before I have
Speaker 1: another big moment to talk about in the evolution toward WiFi.
Speaker 1: That moment happened in nineteen five when the United States
Speaker 1: Federal Communications Commission, or FCC changed the rules about the
Speaker 1: radio spectrum. Every country has rules about which frequency bands
Speaker 1: in the radio spectrum may be used for specific applications.
Speaker 1: For example, in the United States, AM radio has all
Speaker 1: frequencies between five thirty five killer hurts and one thousand,
Speaker 1: six hundred five killer hurts. No other technology is allowed
Speaker 1: to use those radio frequencies. This prevents various technologies from
Speaker 1: interfering with one another. If you didn't have restrictions on
Speaker 1: who could use which frequency, then whatever frequency was the
Speaker 1: strongest had the greatest UH energy behind it in any
Speaker 1: given area would win out and it would be chaos.
Speaker 1: And so the United States divvied up the radio spectrum
Speaker 1: for specific uses, which included not only communications technology but
Speaker 1: also stuff like microwave ovens. Say what, and by the way,
Speaker 1: this is not just the US. Other countries also have
Speaker 1: done this, But it's because technology like microwave ovens can
Speaker 1: generate radio frequencies of their own, not to communicate, but
Speaker 1: that can be a byproduct of their operations. So the
Speaker 1: United States FCC mandated that manufacturers of microwaves and other
Speaker 1: technologies that create these radio waves make sure their products
Speaker 1: only generated radio frequencies within specific bands in order to
Speaker 1: avoid creating interference for other technology. So it's not like
Speaker 1: the US specifically said, hey, let's set aside the slice
Speaker 1: of radio frequency spectrum so that microwaves can talk to
Speaker 1: one another. In staid, they said, hey, let's make sure
Speaker 1: all microwave oven manufacturers be certain that their ovens only
Speaker 1: generate radio frequencies in this slice so that the ovens
Speaker 1: don't interfere with communications equipment. In other words, they set
Speaker 1: aside a certain slice of the radio spectrum and said
Speaker 1: this is your playground. You can create stuff that creates
Speaker 1: radio frequencies in this range, and that shouldn't mess up
Speaker 1: anything that's on either side of that frequency range. These bands,
Speaker 1: the ones set aside for equipment that can generate radio
Speaker 1: waves but aren't necessarily communication tech, are called I S
Speaker 1: M bands. The I s M stands for Industrial, Scientific,
Speaker 1: and Medical. These bands cover several different separate groups of frequencies,
Speaker 1: but two of them include the two point four giga
Speaker 1: Hurts to two point five gig Hurts band and the
Speaker 1: five point seven to five gig Hurts to five point
Speaker 1: eight seven five giga Hurts bands. These are going to
Speaker 1: be very important for our discussions on WiFi. Now again
Speaker 1: we look at five, when the FCC decided it would
Speaker 1: open up three I s M bands to unlicensed use
Speaker 1: that would in flude the two point four giga Hurts
Speaker 1: and the five point seven to five gig Hurts bands.
Speaker 1: Unlicensed use required a couple of technological allowances. One was
Speaker 1: that the transmitters would have to be very low power
Speaker 1: in the one watt range. Another was that gadgets making
Speaker 1: use of that frequency would need a high tolerance to
Speaker 1: interference since other devices were still going to be giving
Speaker 1: off radio waves at those frequencies. Essentially, what the FCC
Speaker 1: was saying is, you can develop technologies that can work
Speaker 1: on these ranges as long as they aren't so powerful
Speaker 1: that they're going to interfere with other technologies, and you
Speaker 1: do it with the understanding that there's already stuff out
Speaker 1: there that's generating radio waves in these frequencies. So whatever
Speaker 1: you create needs to be done in such a way
Speaker 1: that it can tolerate that This decision in set the
Speaker 1: foundation for WiFi, which still would not debut for another decade,
Speaker 1: but that didn't mean there weren't people working on the
Speaker 1: idea in the meantime. One of those people was Vic Hayes.
Speaker 1: Hayes had joined the NCR Corporation in the nineteen seventies.
Speaker 1: In CR, which originally stood for National Cash Register, had
Speaker 1: been involved in various technologies since its founding in the
Speaker 1: late nineteenth century. In CR's goal was to create a
Speaker 1: standard that the company could then use in its own systems.
Speaker 1: The idea was that the standard would allow companies to
Speaker 1: create systems that connected devices like front end retail equipment
Speaker 1: such as cash registers and back end mainframe systems and
Speaker 1: using radio waves instead of cables or other clunky methodologies.
Speaker 1: And they didn't want to go a proprietary route. They
Speaker 1: wanted to create a standard that would work so that
Speaker 1: various O E M companies could create products that used it.
Speaker 1: Hayes had done some work and authoring standards for data
Speaker 1: communications as part of his job previously, and NCR was
Speaker 1: interested in finding an unlicensed use for the two point
Speaker 1: for giga hurts I s M band, n c R
Speaker 1: and a T and T had developed a working predecessor
Speaker 1: to the would essentially evolve into WiFi in nine, and
Speaker 1: that was called wave land. They submitted the design of
Speaker 1: this wireless protocol to the I E E E A
Speaker 1: O two LAND slash MAN Standards Committee. Land, by the way,
Speaker 1: stands for local Area network and MAN for a Municipality
Speaker 1: Area network or Municipal Area network. This led to the
Speaker 1: need to form a new working group within that committee,
Speaker 1: The eight O two Committee to Create a Standard for
Speaker 1: Wireless Networking Communication NCR chose Hayes to head up a
Speaker 1: working group to that effect in nine. The working groups
Speaker 1: designation was a O two point eleven and their goal
Speaker 1: was to create a standard for wireless local area networks. Now,
Speaker 1: a local area network is pretty self explanatory. It's a
Speaker 1: network of computing devices that are locally connected to one another,
Speaker 1: generally contained within a building or maybe a campus of buildings.
Speaker 1: The devices can intercommunicate with one another. A LAND can
Speaker 1: be but doesn't have to be connected to wider networks
Speaker 1: like the Internet, and in the old days, the only
Speaker 1: way you could set up a LAND was to actually
Speaker 1: have physical connections between all the different machines and some
Speaker 1: sort of hub, but NCR wanted to do away with
Speaker 1: those physical connectors and create a standard that manufacturers could
Speaker 1: use to build in wireless communication capabilities directly into their products.
Speaker 1: Hayes had some radio communications background and had previous experience
Speaker 1: helping create communication standards, but still wasn't sure he was
Speaker 1: the right man for the job. As it turned out,
Speaker 1: he absolutely was. He gathered a group of experts together
Speaker 1: and they began to debate what needed to go into
Speaker 1: the standard, and the first big argument was over two
Speaker 1: different modulation strategies, frequency hopping or direct sequence. Both of
Speaker 1: those techniques are meant to use a larger bandwidth for
Speaker 1: transmission than what would otherwise be necessary for the specific
Speaker 1: type of data you're sending back and forth. Frequency hopping
Speaker 1: spread spectrum or f h s S divides a large
Speaker 1: bandwidth into parallel, narrow channels there are large enough to
Speaker 1: hold the data in question. If we go back to
Speaker 1: talking about vehicles and roads, this would be saying, let's
Speaker 1: imagine that you have a really, really wide highway I'm
Speaker 1: talking twenty lanes wide. Uh, and at first you don't
Speaker 1: have any lanes painted in there, it's just an enormous road. Well,
Speaker 1: you could try and use it that way. But frequency
Speaker 1: hopping would allow you to create narrower lanes, lanes that
Speaker 1: are wide enough for a vehicle, so that you could
Speaker 1: have twenty vehicles traveling on there if they all were
Speaker 1: sticking to their own lanes. That's kind of the idea
Speaker 1: behind frequency hopping. The system sends data in a semi
Speaker 1: random way to one of those channels, but that means
Speaker 1: the other channels go unused in the process, and because
Speaker 1: only one channel is in use at any given time,
Speaker 1: you're technically wasting bandwidth equal to the size of the
Speaker 1: channel multiplied by the number of channels minus one channel,
Speaker 1: because you're already using one. So this would be like saying, yeah,
Speaker 1: you have a highway, it's twenty lanes wide. You've painted
Speaker 1: these lanes in there, so you can randomly choose a
Speaker 1: lane between one and twenty and you're fine, But that
Speaker 1: means the other nineteen lanes are going unused. It's not
Speaker 1: an efficient use of space. That was the argument against
Speaker 1: this strategy. Uh, that's obviously inefficient, but it was also
Speaker 1: technically easier to do, and so about half the working
Speaker 1: group wanted to pursue frequency hopping as the modulation methodology
Speaker 1: of choice because while it wasn't efficient, it was easier
Speaker 1: to implement. Direct sequence spread spectrum or d S S
Speaker 1: S introduces pseudo random noise into the signal it sins
Speaker 1: in order to change the phase of the signal itself.
Speaker 1: This creates the digital equivalent of static. It would seem
Speaker 1: to be meaningless information when you received it, but if
Speaker 1: you knew which pseudo random sequence was used to create
Speaker 1: the phase shift, you could reverse that whole process. You
Speaker 1: could d spread the static and extract the meaningful information
Speaker 1: out of it. D S S S is more challenging
Speaker 1: to implement than f H S S, but it also
Speaker 1: is more robust, and so the other half of the
Speaker 1: group wanted to follow that idea. Both of those methodologies
Speaker 1: would allow for multiple devices to communicate across a band
Speaker 1: of frequencies without interfering with one another, and the I
Speaker 1: E E E Rules stated that in order to adopt
Speaker 1: a strategy, you had to secure the support of at
Speaker 1: least seventy of the working group, but each method had
Speaker 1: about of the support. The only solution was to create
Speaker 1: a system that could support both modulation strategies, and so
Speaker 1: that's what the group decided to do. I'll wrap up
Speaker 1: the history of WiFi and give all a low down
Speaker 1: on what the different variations mean in just a second.
Speaker 1: But first let's take another their quick break to thank
Speaker 1: our sponsor. While the working group began to hash out
Speaker 1: the standards that would become fundamental to WiFi, a group
Speaker 1: of engineers, astronauts and astronomers were developing a technique that
Speaker 1: would become just as important. Vick Hayes, whom I mentioned earlier,
Speaker 1: is sometimes called the father of WiFi, but another man,
Speaker 1: John O'Sullivan, also gets that title on occasion. O'Sullivan is
Speaker 1: an electrical engineer, and he focused on radio astronomy. He
Speaker 1: led a team that developed a way to reduce multi
Speaker 1: path interference of radio signals, something that was absolutely necessary
Speaker 1: if you want to have a smooth experience with a
Speaker 1: wireless local area network. His team's work would receive a
Speaker 1: patent credited to the Commonwealth Scientific and Industrial Research Organization
Speaker 1: or c s i r O, which is an Australian
Speaker 1: federal government agency. The really funny thing to me is
Speaker 1: that this research was originally part of an experiment to
Speaker 1: try and detect expanding many black holes. That experiment failed,
Speaker 1: but the technique would end up changing the world once
Speaker 1: incorporated into WiFi. Meanwhile, back in the eight O two
Speaker 1: point eleven Working Group, the standard was getting closer to
Speaker 1: becoming a real thing. The very first version of the
Speaker 1: protocol was unveiled in It had a maximum download speed
Speaker 1: of two megabits per second, which is excruciating lee slow
Speaker 1: these days, and that was only if you could use
Speaker 1: the D S S S approach. Remember, it involved both
Speaker 1: the direct spread and the frequency hopping. If you used
Speaker 1: frequency hopping, you topped out at one megabit per second.
Speaker 1: That didn't exactly cause everyone to throw their cables out
Speaker 1: their respective windows in a fit of joy, but it
Speaker 1: was progress. In ninet, the Working Group released a new protocol,
Speaker 1: and this one was called eight O two dot eleven B.
Speaker 1: It also used D S S S and the two
Speaker 1: point for a gigahertz band, but it was able to
Speaker 1: boost speeds up to eleven megabits per second. While this
Speaker 1: was the second protocol released by the group, it was
Speaker 1: the first to be widely adopted as a wireless local
Speaker 1: area network standard. Chances are, if you were an early
Speaker 1: adopter of wireless technology, this was the standard your computer
Speaker 1: was using, as it was the first that time that
Speaker 1: manufacturers actually embraced this technology when they started making network adapters.
Speaker 1: Later on, the functionality would be built directly onto laptop
Speaker 1: motherboards instead of having to get an adapter that you
Speaker 1: would plug into your laptop. But this was still pretty
Speaker 1: darn slow compared to wired connections. A little later in nine,
Speaker 1: a new methodology launched. It was called eight O two
Speaker 1: point one one A. And yes, these designations are getting
Speaker 1: awfully confusing because the naming standard jumps around a bit.
Speaker 1: We just talked about AT two point eleven B and
Speaker 1: the original one was just called AT two point eleven
Speaker 1: and now we're talking about ATO two point eleven A.
Speaker 1: This one had a couple of major differences from the
Speaker 1: earlier versions. First, it worked on a different band of frequencies.
Speaker 1: Instead of using two point four giga hurts, at two
Speaker 1: point eleven A relied on five giga hurts, And that
Speaker 1: meant the AT two point eleven A standard was not
Speaker 1: compatible with the earlier ones because it was using a
Speaker 1: totally different range of frequencies for communications, so you could
Speaker 1: not use a Dot eleven A device with a Dot
Speaker 1: eleven B device. They talked on different radio frequencies so
Speaker 1: they could not communicate with each other, but it was
Speaker 1: also faster, with the top speed of around fifty four
Speaker 1: megabits per second. In addition, it relied on something called
Speaker 1: orthogonal frequency division multiplexing or o f d M. Now,
Speaker 1: this is a way to in code data across multiple
Speaker 1: carrier frequencies, and maybe someday I'll try to tackle that
Speaker 1: concept in a full episode, but it gets super technical,
Speaker 1: so I'm going to leave it for now because I'm
Speaker 1: running out of time and we still have a couple
Speaker 1: of versions of WiFi we have to touch upon. The
Speaker 1: next one is at two point eleven G. That standard
Speaker 1: debuted in two thousand three, and it uses the two
Speaker 1: point for giga Hurts radio band, so back to two
Speaker 1: point four but like at two point eleven A, it
Speaker 1: also used o f d M, and that would give
Speaker 1: point eleven G a max speed of fifty four megabits
Speaker 1: per second. And because it communicates on the two point
Speaker 1: four giga Hurts range, it is compatible with eight to
Speaker 1: two point eleven B, and so a lot of the
Speaker 1: equipment you could buy, such as a wireless router, would
Speaker 1: have the designation of eight to two point eleven B
Speaker 1: slash G, meaning it could operate across both standards. Also,
Speaker 1: you should know that communication can only go as fast
Speaker 1: as the slowest component involved in the communication. So if
Speaker 1: you had an AT two point eleven B device communicating
Speaker 1: with an AT two point eleven G device, you could
Speaker 1: only hit speeds about to eleven megabits per second because
Speaker 1: that was the top speed limit for B. So it's
Speaker 1: kind of like a a chain is only as strong
Speaker 1: as its weakest link. The connections are only as fast
Speaker 1: as their slowest point. In two thousand nine, we got
Speaker 1: at two point eleven IN. This standard allowed for the
Speaker 1: use of multiple antennas when transmitting information, which increased speeds
Speaker 1: up to four hundred fifty megabits per second. What's more,
Speaker 1: the eleven N standard could operate across both two point
Speaker 1: four and five giga hurts bands, meaning it could also
Speaker 1: communicate with all the older standards like AT two point
Speaker 1: eleven B, slash G and at two point eleven A.
Speaker 1: Then in two thousand twelve we got at two point
Speaker 1: eleven A C and yes I am crying, thanks for asking.
Speaker 1: This standard operates in the five giga hurts range and
Speaker 1: has ends for speeds in the gigabit realm, which is
Speaker 1: wicked fast. It's also really useful if you've got a
Speaker 1: lot of machines connected within that single wireless land, because
Speaker 1: you've got a lot of bandwidth to play with. Now,
Speaker 1: at ce seen some companies showed off devices that are
Speaker 1: using a new version of WiFi has not yet had
Speaker 1: an official release. It's called eight O two point eleven
Speaker 1: a X, and the devices at ce S were reported
Speaker 1: to have a top data transmission speed of eleven gigabits
Speaker 1: per second, which is really wicked fast. It can operate
Speaker 1: in both the two point four and five giga Hurts bands,
Speaker 1: and it should launch sometime in two thousand nineteen officially. Now,
Speaker 1: there are other versions of the WiFi standard that don't
Speaker 1: use the two point four or five giga Hurts ranges.
Speaker 1: They tend to be for other types of technologies than
Speaker 1: mobile devices and computers. They could be for something like
Speaker 1: an in vehicle network, for example, And I didn't cover
Speaker 1: them because you're not likely to work with them yourself
Speaker 1: in an average setting. But I hope this gives you
Speaker 1: a little more information about WiFi. Maybe in a future episode,
Speaker 1: I'll dive into deeper detail of exactly how WiFi works.
Speaker 1: But you have a general idea it's all about radio frequencies,
Speaker 1: mostly in the two point four gig hurts or five
Speaker 1: giga hurts five point seven to five gig hurts range,
Speaker 1: to be specific, and that it involves various modulation techniques
Speaker 1: so that multiple devices can communicate with a centralized router
Speaker 1: or hub in order to send information with to each
Speaker 1: other and also to the Internet at large. So it's
Speaker 1: been a very useful technology, one that has transformed our
Speaker 1: world in meaningful and difficult to anticipate ways, and I
Speaker 1: suspect the that will continue to be the case. In fact,
Speaker 1: we may even see wireless technologies supersed wired ones to
Speaker 1: the point where people who are using high speed connections
Speaker 1: for their jobs or for stuff like high end gaming
Speaker 1: will choose to go wireless rather than wired, because we
Speaker 1: may eventually get to the point where it's just faster,
Speaker 1: it's just less latency, higher data throughput rates. If that happens,
Speaker 1: it's really a game changer. I hope you guys enjoyed
Speaker 1: this episode. If you have any requests for future topics,
Speaker 1: I should cover here on tech stuff, whether it's a technology,
Speaker 1: maybe it's a person in technology, maybe it's a company,
Speaker 1: or maybe there's someone you would like me to interview
Speaker 1: or have on as a guest host, let me know.
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