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Go.

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So let's go back because you mentioned a whole bunch of terms there.

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So let's start right at the beginning.

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In wi fi, we have these things called channels.

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So as an analogy, are you is that kind of like a radio channel where I'm like in my car driving and

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then I go to a certain frequency and then I get a radio station?

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Is that is that what is that what you're talking about?

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That is exactly it.

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Right.

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A channel in WiFi terms is really a range of frequencies.

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So in 2.4 gigahertz, there's 14 channels in the US.

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But we only use we like to use three channels because they're what we call non overlapping.

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And I don't know if you guys recall ever being in the car listening to radio and then you hear two radio

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stations at the same time, right?

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That's that's similar to having channel access points operating on the same channel in the same area.

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And so it's hard to understand what's going on when you have access points on the same channel, providing

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service in the same area for a bunch of devices.

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And think of wi fi as a, as a standard radio, like a two way radio where you have to speak, you have

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to wait for the other person to respond.

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But if you guys try to talk at the same time, nothing happens because no one understood each other

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or that transmission failed because you can't speak at the same time.

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That's how that's how WiFi works.

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It's really like one user or one device transmitting at a time, but it happens very quickly.

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Yes.

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I mean, this is that going back to the analogies.

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I just want to give people, you know, the the foundation and then we can come back to this if DMAA.

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Is that right?

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Yeah, that's correct.

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And and mu-mimo mimo thingamajig.

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So we still need to get to that.

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But let's start with the basics.

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Okay.

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So we've got a channel which is kind of like 20 megahertz as the size of a party starting at 20 megahertz.

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Yeah.

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Okay.

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So then you so that's like a radio station broadcasting on a specific channel.

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In Ethernet, we have carrier sends multiple access collision detection.

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And I think what you've just explained is this carrier sends multiple axis collision avoidance, SMS

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slash CIA, is that right?

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That's correct.

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Now, I've heard some hype that.

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Why Fi and I'm going to not mention names, but wi fi used to be like a hub.

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But now in this new version, it's like a switch type thing.

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And I've read that actually in some technical books because it sounds like what you've said is in this

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new version of wi fi rather than like a 2020 gig megahertz or is megahertz, is that right?

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20 megahertz channel.

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And only one person being able to speak on that channel, like with your your two way radio analogy.

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Now that channel is split up into sub channels where traffic from multiple, multiple people can be

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can be sent at the same time.

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Is that correct?

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It is correct.

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And I still think using the term switch is still incorrect in a way.

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And I think the reason why vendors like to use the word switch or switch like is because of the the

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theoretical speeds that you can get out of WiFi six and even in, in WiFi five.

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Getting over a gig.

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Right.

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Yeah.

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They always mention over a gig, so they're saying it's switch like because in a switch we're used to

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one gig ports.

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I think it's getting closer to being like a switch, but it's still technically not.

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It's still half duplex, wi fi is still a half duplex medium.

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So yeah, we're dealing with collision avoidance and whenever there is a collision, you know, in wi

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fi, you have to back off with a what's termed as OC.

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I sense a collision because I did not get an acknowledgement of my frame from recipient.

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So I'm going to wait because I think there's, there's something going on and it's a random timer.

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And that's what actually slows down your throughput is if you have a lot of collisions, the wait time

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starts to increase, that window starts increasing as you have more collisions.

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But I still think switch like is an improper term.

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Sorry I interrupted you.

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So are you saying it's still.

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It's still acts like a hub, even in wifi six?

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Yep.

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It's it's because we're subdividing the channels.

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And when you subdivide those channels, it's still a very specific frequency.

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So a device will lock on to that specific frequency, and only that device should be using that frequency.

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And that's why I say fi six will be better when all the devices are using wi fi are all wi fi six.

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So when you mentioned about channels and I'm sorry to hop on this, I just want to try and get through

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some of these terms and then we can like take it to Wi-Fi six.

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We had.

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A single channel.

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And then you mentioned in AC, I think that they do this thing called channel bonding or something.

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Can you explain that?

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Yeah.

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So channel bonding is is very common in the five gigahertz frequency.

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And so in five gigahertz, you have multiple channels, 20 megahertz channels, I think about 24 or

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25.

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And so the most common the first one is Channel 36, and then your next channel is Channel 40.

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If you bond those two together, Channel 36 and 40, put them together, you now have a 40 megahertz

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wide channel and you have a channel bigger, big enough to hold more data.

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So your throughput goes goes higher.

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So is that the analogy?

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Like, I had a single lane and I've got two lanes on a highway or something.

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Yeah, that's correct.

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Yeah.

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Yeah.

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You doubled your lanes.

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Right.

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So if you look at traffic as an example, single lane, all that traffic behind in that single lane,

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it's slow.

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But if you open up a lane, you ever notice how some cars just start going to the second lane and now

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you can now it speeds up.

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There's more cars going down the road.

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That's a that's a good analogy.

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Yeah.

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So I mean, the AC didn't actually increase the speed of like a single channel or did it do that in

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addition to, you know, increasing the speed by giving us more channels?

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Yeah, it gave us the 160 megahertz channel with which I personally don't use anywhere.

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And there's a number of reasons why which we can dig into.

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Yeah.

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So I mean the, the way just trying to understand this, the way that the speed increased is because

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we got more lanes and then we can bond that and send more data by using multiple lanes from the from

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the access point down to a client.

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Yeah, that's correct.

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So can you explain MIMO or how do you pronounce a MIMO?

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And, you know, I believe there was a difference between AC and AX.

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Now that's quite a big change.

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Yeah.

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So there's MIMO was introduced, I think back in 802 11, and that's a multiple input, multiple output.

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And that's just meant to the best way to explain this is to speed up the the medium by using multiple

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radios on your access point or your devices and being able to transmit, again, more data.

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That's we're just trying to transmit more data as fast as we can with without breaking the law of physics.

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Yeah.

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Yeah.

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So I saw you had an interview and you were talking about this issue about the law of physics.

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And it seems like this is a major issue for a lot of wireless deployments, is this you can't bend physics

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and you have to you know, you'd love to go faster, but physics doesn't allow you type thing things

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that.

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Right, right.

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And a lot of it is also because of the unlicensed frequency that we use.

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If you have a license frequency, which our devices can't use that because it has to be tuned to that

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frequency, then, I mean, that frequency is all yours.

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It's a lot cleaner.

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You can do potentially like full duplex wireless technologies and that's that's actually capable that's

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out there.

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And but we see that a lot with point to point transmissions explain this thing about the the the the

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multiple antennas because I see like Netgear and some of these vendors have like a whole bunch of antennas

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on their AP.

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So how does it work with these antennas?

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You know, why does how does it work practically to send more data?

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Do the antennas work on different frequencies or how does it work?

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Yeah.

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So the there's a set of radios that will work on 2.4 gigahertz and a set of radios that will work on

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five gigahertz.

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And then you'll have multiple what's called radio chains, right?

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You'll see like two by two, three by three, four by four.

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All that really means is you got to, to transmit and to receive three, transmit, three, receive.

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And so what that means is you can use that number of radios to transmit data.

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And the reason why more antennas is usually good is because you can now use like antenna diversity.

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So maybe one antenna can hear a transmission better than another radio.

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And so there's these algorithms that that these vendors use to try to take advantage of that through

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one antenna.

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And then there's a lot of what we call reflections because signal bounces around everywhere.

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Yeah.

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And maybe another antenna can hear some of that transmission.

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And so what it'll try to do is combine those signals internally and try to basically boost that receive

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signal so it can what's called modulate that signal, take that that signal in the air and make it digital

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and make it understandable.

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I think that's really important.

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Sorry, I interrupt you.

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You carry on.

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And I'm saying that's that's basically why we have more antennas on access points is that also helps

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increase your your your speed, your throughput on your wireless network.

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You can send more data that way.

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And the signal is more resilient with with multiple antennas because now you've got more ears listening

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and, and more mouths talking.

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I mean, I think it's a really important point that you raised.

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I mean, the whole idea here is we're taking a digital stream of zeros and ones and then we modulating

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it into waves on the air and then somehow trying to modulate that on the other side back into zeros

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and ones.

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So, I mean, I like your analogy of the radio stations, because if there's a lot of noise from other

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devices communicating, it becomes difficult to modulate that.

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So pushing you on this now.

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So when if I've got I mean, you call it radio chaining.

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If I've got like two by two type thing where I've got two transmitting and two receiving, they still

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use in the traditional sense.

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Only one channel, is that right?

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Or do they split channels, use multiple channels?

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How does it work?

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Yeah, it's it's based on whatever channel you've configured your access point to use.

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That's what those, those radio chains will use the operating channel that's configured.

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So whether that's 20 megahertz wide or 40, it's going to use whatever channel you've configured to

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to use it for.

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So I know in WiFi six they suddenly have increased this.

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So can you just talk around that?

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And I don't want to try and mention the values because I'll get it wrong, but I know in a sea it went

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higher and then actually went higher again.

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About the channels.

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Yeah.

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So all the radio chaining is at eight by eight by eight or something.

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Yeah.

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So they've increased that in WiFi 6 to 8 by eight which there aren't many access points right now that

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are that are eight by eight.

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And that's just a lot more radio chains because of how complex wi fi is.

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Now with WiFi six and all the sub channels you have, you're going to want a lot of antennas to to be

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able to grab that signal and also to be able to send that signal.

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And also a lot of that depends on another term, mu-mimo, which we can get into also.

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Yeah, let's talk about that.

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I mean, so firstly, I mean, what you're saying is eight by eight means eight transmit eight receive

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top setup.

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Yeah.

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Right, right.

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That's correct.

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And and that's greater than a a C, which is four by four.

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Is that right.

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Yeah.

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So I mean they've basically allowed you to add more radios to get better throughput based on like what

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you said.

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More ears and more mouths I suppose is the analogy.

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Yeah.

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And it's not just for the access points, it's for the devices to the limiting factor.

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For that, though, is the reason why you don't see an eight by eight phone is because that would probably

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drain your battery, you know, within minutes because of how many electronics have to be powered up

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in order to have an eight by eight.

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Right.

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Most of our mobile devices are two by two to transmit to receive.

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And so maybe the question is, well, why?

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Why should I have an eight by eight or even a four by four if my devices are two by two?

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Yeah, well, when, when you talk about things like mu-mimo, you could use different antennas to send

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data to like a beam beamforming like send a signal out a specific antenna towards a specific direction

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passively because the antennas aren't an active antenna.

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It's not, it's not changing its internals to like send data, but it's going to try to form a signal

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towards a general area of where maybe that device would be.

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So I could send a device to a transmission to you.

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David But then somebody else could be sitting on this side and I could send a transmission there using

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different antennas.

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And the thing is, for me, with mu-mimo or multi user, multi user, multiple input, multiple output

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is that it's very hard to to really see if that works well.

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It's hard for me to see if that works with the technology I have access to.

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Right.

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There isn't say like a command line where I can go, how well is Mu-mimo working?

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And so and also Mu-mimo depends on the spatial diversity of the clients.

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So if you have ten clients all clustered together, it's kind of hard to beam form to one of those ten

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clients because they're all in the same general direction.

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And that's where you'll hear a lot of people saying like, maybe Mu-mimo doesn't work.

235
00:14:18,880 --> 00:14:23,440
But for me, it's I don't know how to check if it actually works.

236
00:14:24,450 --> 00:14:24,830
You mean?

237
00:14:24,830 --> 00:14:25,880
It's very interesting what you said.

238
00:14:25,880 --> 00:14:31,520
So just so that I understand, because once again, I'm going to be the guy that he's the slowest student

239
00:14:31,520 --> 00:14:32,240
in the room.

240
00:14:33,020 --> 00:14:37,820
Beamforming is, as you explain it, so you can push a beam this way and a beam that way to try and

241
00:14:37,820 --> 00:14:39,320
get better throughput.

242
00:14:39,680 --> 00:14:46,100
And then just on this mu-mimo, what there's a difference now, a big difference that I read between

243
00:14:46,100 --> 00:14:47,660
this and AC or wi fi five.

244
00:14:47,660 --> 00:14:50,570
Isn't there something to do with the receiving and transmitting?

245
00:14:50,690 --> 00:14:51,650
Yeah, it allows.

246
00:14:51,650 --> 00:14:56,270
So in AC or wifi five, it was what they call downlink.

247
00:14:56,270 --> 00:15:02,390
So from the AP to the client, you could do mu-mimo with 11 ax.

248
00:15:02,390 --> 00:15:04,640
You can do mu-mimo in both directions.

249
00:15:04,640 --> 00:15:08,270
You could do it downstream and also from the client back to the AP.

250
00:15:08,870 --> 00:15:14,330
So does that mean that getting back to like your your example, it's not switch, it's not a switch,

251
00:15:14,330 --> 00:15:20,420
but it's switch getting closer to switch like so that means that the AP can send to multiple clients

252
00:15:20,420 --> 00:15:23,810
at the same time, but the multiple clients can send back at the same time.

253
00:15:23,810 --> 00:15:24,410
Is that right?

254
00:15:24,920 --> 00:15:31,010
Yeah, it's getting to where it seems like a switch, but it's still half duplex.

255
00:15:31,020 --> 00:15:34,340
Yeah, but the idea is, is like, if you.

256
00:15:34,370 --> 00:15:35,000
Sorry, go on.

257
00:15:35,150 --> 00:15:35,900
No, no, no, go ahead.

258
00:15:36,080 --> 00:15:38,450
Now I'm just going to say my apologies to everyone.

259
00:15:38,960 --> 00:15:41,120
Rules in California, I'm in the UK.

260
00:15:41,150 --> 00:15:42,320
There's quite a bit of delay on the link.

261
00:15:42,320 --> 00:15:45,350
So forgive us, you know, for, you know, speaking one another.

262
00:15:45,350 --> 00:15:46,070
This is the problem.

263
00:15:46,070 --> 00:15:47,450
We're doing wireless here, dude.

264
00:15:47,480 --> 00:15:52,940
It's like it's not full duplex but sorry you carry on the.

265
00:15:53,240 --> 00:15:58,340
I already lost my train of thought there but now so I was going to say, you know, it's not like a

266
00:15:58,340 --> 00:16:04,070
switch you it's kind of getting to switch like with where the app can send at the same time sorry,

267
00:16:04,070 --> 00:16:08,570
the app can send to multiple clients at the same time and the clients can send back at the same time.

268
00:16:10,320 --> 00:16:12,180
So did you want to say something about that or.

269
00:16:12,180 --> 00:16:13,380
I'm going to push you now.

270
00:16:13,590 --> 00:16:14,140
Yeah.

271
00:16:14,160 --> 00:16:21,390
So the caveat there is we always have to remember with WiFi six is we're taking one channel and say

272
00:16:21,390 --> 00:16:29,550
that's channel 36 and we're dividing that channel into sub channels, which are very small frequencies.

273
00:16:29,550 --> 00:16:32,700
So that's what the devices tuned to.

274
00:16:32,700 --> 00:16:38,640
They tuned to that small frequency which which Wi-Fi six, it's called resource unit.

275
00:16:38,820 --> 00:16:41,550
And so the resource unit is a small channel.

276
00:16:41,550 --> 00:16:45,030
And when I say channel, a channel in wi fi is also a frequency.

277
00:16:45,240 --> 00:16:52,080
So it's a very small frequency that a device will tune to and transmit or receive on that frequency.

278
00:16:52,080 --> 00:16:59,250
And that's how you can get the multiple devices being able to receive or transmit because then the app

279
00:16:59,280 --> 00:17:06,210
with its, you know, chips and the math can determine, Kate, that client is on this sub channel of

280
00:17:06,420 --> 00:17:12,810
channel 36 and that clients on this sub channel, it coordinates all that and the resource units, it's

281
00:17:13,200 --> 00:17:16,770
it could expand into different combinations, right.

282
00:17:16,770 --> 00:17:25,290
So with resource units, if you if a device took up the full channel, that's one resource unit.

283
00:17:25,290 --> 00:17:30,990
But the full channel, technically that's 242 resource units and that device can use it all.

284
00:17:31,020 --> 00:17:34,320
You can further subdivide that channel into smaller resource units.

285
00:17:34,320 --> 00:17:39,030
I'm not going to bore everyone with all the numbers, but let's say there's two devices.

286
00:17:39,030 --> 00:17:45,060
You can split that channel into two channel to sub channels and they can transmit and receive at the

287
00:17:45,060 --> 00:17:45,540
same time.

288
00:17:45,540 --> 00:17:46,590
So that's kind of the logic.

289
00:17:46,590 --> 00:17:50,460
It goes further down and you could have up to like eight sub channels.

290
00:17:52,020 --> 00:17:52,230
Yes.

291
00:17:52,230 --> 00:17:53,460
I mean, this is quite a change, isn't it?

292
00:17:53,460 --> 00:18:00,270
Because in the past we had like a channel 20 megahertz and only I could speak on that or you could speak

293
00:18:00,270 --> 00:18:00,750
on that.

294
00:18:00,750 --> 00:18:03,780
But now they breaking it up into these.

295
00:18:04,020 --> 00:18:06,210
Did you call it resource units or sub channel type thing.

296
00:18:06,210 --> 00:18:06,420
Yeah.

297
00:18:06,420 --> 00:18:06,840
Yeah.

298
00:18:07,320 --> 00:18:11,610
In the in the in the draft, it's called resource units.

299
00:18:11,610 --> 00:18:16,920
But really I like to say call it sub channels because we speak in channels anyways.

300
00:18:16,920 --> 00:18:18,330
So that's what it really is.

301
00:18:18,990 --> 00:18:19,230
Yeah.

302
00:18:19,230 --> 00:18:22,860
So basically you're taking 20 megahertz and you splitting it in two.

303
00:18:22,890 --> 00:18:30,000
So you and I both get ten megahertz so we can both send at the same time because rather than using the

304
00:18:30,000 --> 00:18:33,200
full channel we're using one of these sub channels.

305
00:18:33,210 --> 00:18:33,750
Right.

306
00:18:33,750 --> 00:18:34,120
Yeah.

307
00:18:34,120 --> 00:18:37,410
But I still see a sma slash a you see sma slash.

308
00:18:37,440 --> 00:18:42,420
It's still a collision avoidance because there's still possibility of collisions that can happen.

309
00:18:42,840 --> 00:18:43,170
Right.

310
00:18:43,170 --> 00:18:48,540
And then one thing I didn't mention before is we still have this transition from WiFi five to WiFi six.

311
00:18:48,540 --> 00:18:50,940
So you're going to have a mix of devices.

312
00:18:50,940 --> 00:18:56,160
And the if anything, that's not Wi-Fi six is not going to be able to take advantage of those WiFi six

313
00:18:56,160 --> 00:19:00,180
capabilities because you have to be a Wi-Fi six device.

314
00:19:01,200 --> 00:19:01,420
Yeah.

315
00:19:01,480 --> 00:19:06,780
So all the previous versions of wi fi, they use the full channel, is that correct?

316
00:19:07,140 --> 00:19:07,620
Yeah.

317
00:19:07,620 --> 00:19:12,300
So if you wanted to transmit and I wanted to transmit, I'd have to wait for you.

318
00:19:12,300 --> 00:19:15,690
But with I, I'd have to wait for you to transmit first and then I can transmit.

319
00:19:15,690 --> 00:19:20,790
And then with wi fi six, the AP can just subdivide the channel and we can both transmit at the same

320
00:19:20,790 --> 00:19:21,150
time.

321
00:19:21,150 --> 00:19:26,610
So it's like, it's like going to a fast food drive through, you know, single lane drive through.

322
00:19:26,640 --> 00:19:26,980
Yeah.

323
00:19:26,980 --> 00:19:32,010
You had to wait for the guy in front of you to order, but then they came out with two lane drive thrus.

324
00:19:32,250 --> 00:19:34,980
So now you can, you can place two orders at the same time.

325
00:19:34,980 --> 00:19:39,300
Like they try to make that efficient, that line more efficient and make you go through the line faster.

326
00:19:39,600 --> 00:19:41,340
It's it's very similar to that.

327
00:19:42,580 --> 00:19:43,180
I mean, that's great.

328
00:19:43,180 --> 00:19:47,260
I mean, I can understand the analogy of using a switch because it kind of sounds like that, but not

329
00:19:47,260 --> 00:19:49,960
entirely because it's still Kerry avoidance within that channel.

330
00:19:49,960 --> 00:19:55,090
And if you have a an old device broadcasting like crazy in that channel, that's going to affect you.

331
00:19:55,480 --> 00:19:56,020
Exactly.

332
00:19:57,220 --> 00:19:58,270
No saying exactly when.

333
00:19:58,290 --> 00:20:02,350
This is what Wi-Fi six is trying to solve is that density problem.

334
00:20:02,350 --> 00:20:07,960
Because what I like to tell people about wi fi is you have this pie on the table, right?

335
00:20:07,960 --> 00:20:09,370
This delicious looking pie.

336
00:20:09,400 --> 00:20:13,450
If you were the only one there at that table, you can have that pie all to yourself.

337
00:20:13,450 --> 00:20:17,260
But as soon as somebody else comes, now, you got to split that pie.

338
00:20:17,290 --> 00:20:18,910
Maybe in half, right?

339
00:20:18,910 --> 00:20:21,940
Depends how hungry you guys are for for data.

340
00:20:21,940 --> 00:20:24,550
And then the more people come that's smaller.

341
00:20:24,550 --> 00:20:26,590
You get a smaller slice of that pie.

342
00:20:26,620 --> 00:20:31,750
That's kind of like that's kind of how wi fi is, is the more people there are, the a small sliver

343
00:20:31,750 --> 00:20:38,550
of airtime you're going to get because this this is the first time I mentioned airtime because wi fi,

344
00:20:38,550 --> 00:20:39,970
it travels through the air.

345
00:20:40,000 --> 00:20:44,620
What we're trying to do is get people to communicate and get off the air faster.

346
00:20:44,620 --> 00:20:45,120
Right.

347
00:20:45,310 --> 00:20:48,490
Transmit your data, get off the air so somebody else can can transmit.

348
00:20:48,490 --> 00:20:53,860
And so that's what we're trying to make more efficient is that air time utilization, that air time

349
00:20:53,860 --> 00:20:55,780
efficiency is what they what they call it.

350
00:20:56,840 --> 00:20:56,910
Yeah.

351
00:20:57,040 --> 00:21:00,400
I mean, I'm glad you've used that analogy of the pie because I mean, the problem I think with wi fi

352
00:21:00,400 --> 00:21:03,150
is we've only got a certain number of channels, haven't we?

353
00:21:03,160 --> 00:21:06,010
So I mean, you mentioned like they're trying to extend the channels, is that right?

354
00:21:06,010 --> 00:21:07,990
In Wi-Fi six, give more channels four.

355
00:21:08,230 --> 00:21:09,940
They're not trying to extend the channels.

356
00:21:09,940 --> 00:21:12,700
There's a separate project where they're in.

357
00:21:12,700 --> 00:21:15,130
I know in the U.S., I'm not sure about other countries.

358
00:21:15,130 --> 00:21:22,660
They're trying to expand the number of another frequency, like the six gigahertz frequency for wi fi.

359
00:21:22,660 --> 00:21:29,380
And if they did that, we would have a lot more frequency to use and distribute users across different

360
00:21:29,380 --> 00:21:29,950
frequencies.

361
00:21:29,950 --> 00:21:33,850
So that way everyone can get access to different pies.

362
00:21:34,060 --> 00:21:39,820
There's more pies available, and that way there's less what's called this?

363
00:21:39,820 --> 00:21:45,300
The first time I'm going to say this contention, because if you think in terms of a switch, right,

364
00:21:45,310 --> 00:21:51,580
you you have a single port, a switch, switch port and whatever is connected there, that's a single

365
00:21:51,580 --> 00:21:52,300
collision domain.

366
00:21:52,300 --> 00:21:52,510
Right.

367
00:21:52,510 --> 00:21:57,130
I'm sure your your audience will understand that with a hub.

368
00:21:58,140 --> 00:21:59,850
Hopefully you guys know what a hub is.

369
00:22:00,510 --> 00:22:03,120
Yeah, the audience is a level.

370
00:22:03,120 --> 00:22:04,380
I think most people know what a hub is.

371
00:22:04,380 --> 00:22:07,290
Yeah, it's just I haven't seen a hub in so long except for wireless.

372
00:22:07,290 --> 00:22:08,130
I can go and get you one.

373
00:22:08,130 --> 00:22:12,870
I've got one upstairs, but a hub is a single collision domain.

374
00:22:13,020 --> 00:22:14,760
Yeah, that's what wi fi is.

375
00:22:14,760 --> 00:22:15,240
It's like.

376
00:22:15,240 --> 00:22:16,170
It's like a hub.

377
00:22:16,170 --> 00:22:17,700
It's a single collision domain.

378
00:22:17,700 --> 00:22:24,240
And so when we have different channels, we're trying to create different collision domains, because

379
00:22:24,240 --> 00:22:28,560
if you have Channel one and Channel six, those are two collision domains.

380
00:22:28,650 --> 00:22:34,950
But if you have an API on Channel one, let's say here's a room, here's an app and an app right here,

381
00:22:34,950 --> 00:22:40,140
both on channel one that is effectively a single collision domain because they're on the same channel.

382
00:22:40,470 --> 00:22:46,950
So what we're trying to do is create multiple collision domains so that we don't run into what's called

383
00:22:47,400 --> 00:22:54,390
like co channel contention, where a lot of channels, a lot of devices are contending to use airtime

384
00:22:54,390 --> 00:22:57,210
because they're all they're all communicating on the same channel.