Cisco CCIE Enterprise 350-401 Topic: Infrastructure Part 6
December 14, 2022

39. BGP Best Path Selection Lab

Let us perform the lab task in the lab. What we are going to do, first of all, is show you the entire setup that we have here. As you can see, we have four different autonomous systems. Say A is 50, then A is 100, which is 900, and a S is 200. The router is now router seven, as seen from a S 200. For example, I have a loopback, and that loopback is loopback seven, seven, seven. And for that particular network, I’m advertising with the BGP network command. So they will go and reach Ace 900, and then they will go and reach Ace 100. It will travel inside a S100 to router number two. So, before I show you the entire path and how it gets there, let me quickly show you the configuration that we have. So if I go here and check the configuration, sure.

And in Section BGP here, you can see the configuration, and these IPS that you are seeing over the interface—these IP addresses—you can refer to the topology diagram as well. So router one here, you can see it has very minimal configuration; it has one interface, and then we are advertising one of the networks. Then, on router number two, you can see the BGP configuration, where we are running EIGRP inside the ASA. Then there are two neighbour peer commands from routers 3 and 4. And, of course, we have one EBGP configuration with router 1, as well as one BGP configuration with router 3. So let me do this. Here you can see the configuration for router three. Router 3 also has an EVGP relationship, as shown in the diagram. So, as shown at the top, the EBGP relationship with A is 90 to 0. Likewise, we have a router-four configuration for BGP. Then we have the BGP configuration for router five, and then you can see routers six and seven as well. This is the router six configuration, and finally, router seven. Now what we have done is that you can see that inside router seven we are advertising one of the loopbacks with the VGP network command, and then we are going and seeing how it is reaching router number two. So if I go and check IP BGP, first of all, I’ll show the BGP table. So clearly, you can see this as it is getting prepended. So the originator for that is 200. So you can see that this is seven, seven, seven.

So the originator is now 900, and it is approaching S 100. Now you can see that you are on the correct and best path, so it is telling you 172 1 7 if you check 172 1 7. So this is the best path; via this, it is going and reaching here, although you have the alternate path as well, which is 107, 216, and 6; that’s the only star we have, and the star means valid. So, let’s see what happens if I go check the IP route for this specific network. So here you can see that it is coming via 172-1712, and they have learned that this is the router tag and how many hops, et cetera. Correct. As a result, it is learning. So what I want at this point in time is that it should go and learn via this particular neighbour, not via this neighbor’s other thing that we can see here that is changing the next stop. So, if I go here and look at the diagrams, it will obviously change the next top whenever it goes and moves to the EBGP. Correct. So from here, either from router three or from router four, it will go and reach router number two. But suppose you have another router in the same network as router two. So at that point in time, you can see some differences.

So you’ll need to exercise some next-half self-command. Correct? If I go to router number one and check show IP BGP now, who is the next hop since this is the EBGP relationship for this route? So he is saying that his next step is changing, and that’s okay. But if router one is also inside AS100, then that will be the problem anyway. So what is our target here? We want to learn this particular route from this next person or from this peer. So let’s use the weight attribute. Before that, I want to create an IP prefix list. So IP prefix lists say loopback 777 is the name of my network. Even I can go and give the sequence number, and then I can use this if I want. So sequence ten and then permit 77732. All right. Then I’ll go make one route map. Say my name, please. Then what I want here is to match, so let’s see, match, and see what our options are. So match the IP address, and that is the prefix list. What is the prefix list? We have created this. Okay, now I’m going to set the weight with this. Say, for example, 8989. Then I will give a default statement for route mapping where I will not match anything. Say, for example, that you are at Route 100 and want to check the route map configuration. So we’ve created a single IP prefix list. We followed the route map. Then we have to set the width for that. Now we should go and apply this to the neighbor. And to which neighbour do you want to apply? So you want to apply this to 172, one six-one we want to apply to this neighbour that’s going, and what’s the route map we have? Because this is weight, the route map’s name is “my TT.” As a result, I’d like to apply in the indirection.

So, as you can see, it is telling you that this is not the configuration that we have done. If you go and check, we have created the neighbour with a loopback, correct? So we should apply the loop-back statement. So here you can see that I have a neighbor, and the neighbour is router number four. That is on the route map, and that will be in my direction. All right. Now, if you go and check IP BGP clearly, you can see that the next stop did not get changed. So, for example, that’s a problem actually with IBGP, and that’s just to prevent the loop. So that’s a loop prevention mechanism. So what does it mean that you can see when the routes are coming and when they are entering as they put their IP as a next stop here? When it reaches here, it should put these IPSas on hold first of all, correct? So we should go and make some small changes in the configuration. So let me go and make a small change in the configuration. So let’s do this. I can go to the third router, say routerBGP 100, and tell my neighbour to come up next. Likewise, we can go to router number four as well. Then we can tell that the next shop is router BCP100’s neighbor. Now, if you go here and check IPGP, you’ll see that the next shop will get changed. Otherwise, I’ll force this VGP to converge. Here you can see the risk. The order of precedence does not change, but the priority does. You can see that the Wait update has been done, and it is going via the bottom router.

So here you can see that Wait has done his job, but it should change the next stop as well. And now you can see that they have changed the next stop. That’s correct. Actually, the weight has been changed. The next stop has been changed. So this is the use case with the weight. Now, what we want here is, instead of weight, the same thing I want to do with the local preference. So first of all, I’ll go to routerBGP 100 and I’ll remove this command. I don’t want this wait, for example, so we don’t need this wait. And then we want to use the local preference. So for local preference, let’s go and check the route map as well. Because now I have a local preference, I want to create one route map as well. This time, I don’t want to apply this policy to R 2, but rather to R 3 and R 4. So how the local preference is working is that they are much more intuitive than weight, and their attributes can flow inside the ES. That’s the key we have. So, what we can do here is, first of all, see how the 777 is getting reached by router number two. Then here, over router three, I will set the local preference to 300. And for router number four, I’ll set the local preference to 150 because I want it to go in this direction. Assume we can pull it off. I’ll go and create one more network here. So, for example, eight, eight, and eight as well. Already, we have 7,777. I’ll create one more. 77777, for example, should go in this direction, and 8888 should go in this direction. So, how do we go about doing that? So, let’s think about that. Let’s try to perform that task.

40. BGP Best Path Selection Lab Continue

And then I want to create one more loopback because the deterministic criteria, I want to put some conditions inside the route map so I can go and create the network statements like this, okay? So I have two different IP prefix lists, and even though I can copy and paste the same configuration to four as well, just to save our bandwidth, is that all right? So once we get here, we should go ahead and create the route map. Say local preference what I want to this route map save permit in match IP address and that is the prefix list seven. For this I want to set the local preference, for example, eight eight. Okay, then I’ll go to the other statement that is, say, 20.And then I’ll go and match the address that is this guy here. And then I want to set the local preference a little less. So here you can see the strategy for seven-seven-seven, where we have the higher local preference. Similarly, I’ll go and create one more route map here towards router number four, where I want to match the 88. So statement number one, I’ll go and match the IP address that is eight-eight.

And then I’ll set the local preference, say for example, 9999, that is very high. And then I can go to the other statement where very high. And here for eight, what is the local preference? Very low. So just the condition for seven, seven, we have high local preference for it rated. We have low local preference. Here the reverse is correct. Now we should go and apply this to the neighbor. IP router BCP 100. My neighbor is this guy here. And then the route map is local preference in direction. Correct. Now here also, I can go ahead and check router BGP 100. My neighbour is this guy. And the route map that we are going to use is the local preference name and then the inward direction, right? Now, if I go here, that should be the best path. So here we can clearly see that they are losing the backup. So here you can see that now the routes are converging and getting set with the correct local preference. But still, if you want to clear the IPBGP star, you can go and do that. And then you can go and check show IP BGP. So it will take some time, but it will build that out. And clearly, whatever our target was, we were.

41. BGP AS-Prepend & MED

As pathologists and doctors, we can also testify. Now the difference between Ace Path Prep and Meg, the local preference, and the weight is that the rules for prepaid are going to be applied to the outbound routes, which will dictate the best inbound path. This is just the reverse of what we have studied and done. So, in this case, suppose you have route 1051 and want to compare B to D to see how it will reach routers C and E. So in that case, what we can do, for example,  in the case of a path prep, is know that a path is like a number of hop count.As a result, if the number of as is lower, that will be preferred. So, if I go into router B and add a prepend 134 times, the same route that she will get from D, E, and C will be a hundred and its own AC 900 like that rather than going and getting the route with a 100 multiple times.

So, naturally, it will prefer and learn the route from D. So here you can see that the same way we can create the access list or prefix list, we can create the route map, and then inside the route map we can go and set the ACE path prep. We can use any number, for example, 200, and then we can go and apply to our neighbour that we have applied for an example weight and that we have seen for the local preference as well. So we are applying to this neighbor, which means we are making the path B to C as bad as A. So obviously, you will see that the traffic will be preferred from 172-1711, and here you can see in the output that yes, we have the valid and best route via 172-1711 rather than 172-1611. The same methodology can now be used, and the same result can be obtained with the mere, which is nothing more than a multi-exit discriminator. By default, it will be zero. We know that metric values are lower and better. Assume you go to router B and set a higher Meg value, then the routers D and E to create the Cpath will be preferred again; similarly, you can go and create the route map. You can match the access list or the prefix list, and then you can set the Meg volatile value. For example, 200 here. That is much bigger than zero. So that’s the reason. Here again, you can see that zero is better or lower than 200, and that’s why the traffic is preferred over A. So we can accomplish the same thing with preprint that we can accomplish with me. All right, so let’s just stop here.

42. Wireless Basics 01

In three, we must learn and understand the fundamentals of wireless technology, the AP, how the APS will connect to the control plane’s WLC, and how to perform baseline troubleshooting. So let’s just start with the basics of wireless. Now, wireless is very different from wire technology. We know that in wire technology, there are routers, switches, cables, and modern endpoint systems with nick cards that connect the interfaces.

And this is how network infrastructure is constructed. Aside from that, wireless technology is a free medium that is not entirely accurate. Still, in wireless technology, you have air as a medium or some sort of transport, but not the physical transport. So maybe wire inside wire also carries the wireless waves that go from one place to other place.But again, that is not the exact use case we have. Later in this course, you’ll see that we have different types of frequency ranges, different types of wavelengths for different wireless frequencies, and which particular range we’ll use on land. It’s actually a broad thing, and in that broad thing, we are using one small spectrum or one small slice of that wavelength for our wireless networking or for our wireless use. So let’s start with the very basics, and then slowly we’ll add things to this. We’ll add some more concepts to this. As you can see in the diagram, there is a sender and a receiver. That’s the normal way of communicating. So if there is a receiver, if there is a sender, and if they are connected, then only communication will happen, correct? In the case of wireless, it shows that there is a rope between the sender and the receiver, but there is no visible media, as in wireless. But you have the waves. For example, use the term “wave.” So here, you can see that you have the electric and magnetic fields. In the diagram, you have E and M, which are propagating inside the air.

So air is the medium where it is propagating. Now, if this wave is not constant, suppose you start one person and stop, so that will not reach the receiver. So that means your wave should be constant. So it should have constant height up and down. So you can see that you have ups and downs. That means the flow of the wave should reach the destination. So, with this slide, you’ll understand, “Okay, we have media air, and then we have the wave.” That type of wave is electric and magnetic. So we have electromagnetic waves. Now, again, you can see that you have one sender who will send, and then you have the receiver who will receive. So at this point in time, I assume that everyone knows that we have the access point. We know that you have an access point. Nowadays, every network has an access point that sends wireless signals. And then, for example, you have a laptop where you have the receiver, so he’s receiving, and you have an access point that is sending. Okay, so in order for communication to occur, your receiver must be able to receive, and the sender must be able to send in all directions. Later on, we’ll study about canteen and all, and we’ll see what the use case is for the direction of sending the frequencies and the wavelength of sending the signals. Okay, so you’ve got a sender and a receiver. All right, then what is frequency? The up-and-down cycle in one second is defined as frequency. Okay, so let me show you the definition. I’ve also taken the definition. So here you can see that the frequency is the number of times the signal makes one complete up-and-down cycle. So when you go up and down in 1 second, suppose you are making 4 up and down in 1 second, so that’s 1 second, and your frequency is 4 Hz.

Now again, what is Herch? Obviously Herch. This is one of the scientists who has done research, developed or given his thesis and papers related to electromagnetic waves, and written so many books. All right, so hertz is the most commonly used frequency unit, and there’s nothing other than one cycle per second. So you’re sending the wave now. Remember you have rope and you are sending the wave; how many ups and downs do you have in 1 second? That is 1. Suppose you have 1000, or tens of thousands, or hundreds of thousands, et cetera, of thousands of thousand. So that will be determined in hertz, kilohertz, megahertz, and gigahertz. We are very specific about gigahertz in our wireless LAN network, so we will go and discuss. So now this is the thing. I told you that we have a wide range of spectra. So we have cosmic rays, gamma rays, and X rays. We know that some things come from the sun, and that some of the rays are dispersed throughout space. Some of the rays we are using for medical and health care as well—ultraviolet light, microwaves—we know all these things. But what we are going to use, we are going to use here in terms of gigahertz. So, if you see this spectrum beginning at zero, I’m focusing on or focusing here; let me focus this spotlight. From one gig to ten gigs Okay? So we have a one gigabyte to ten gigabyte slice. So there’s 2.4 GHz wireless and 5 GHz wireless.

And then again, you have the bands for that. So we are going to focus on this spectrum, and this frequency is actually what we are going to use inside our wireless network. Okay? At 5 GHz, for example, you can see it starting at five, going to one five, and ending at 5825. Remember? This is in gigahertz. Now, if you convert this into megahertz, that means that there are 100,000 MHz. Let’s make this easy. So say, for example, you have ten, then ten free, then ten six. And, if I’m not mistaken, this is a ten nine. So your Mega is ten six. Ten.3 is your kilo. So this is your kilo, this is your mega, and this is your gigahertz. Okay? Suppose this is the range you have. 5.15 to 5.20, for example. So what is the difference? Actually, the difference is 100.1 kHz. And now, if you convert this into meg, what will happen? Perhaps 1 MHz. Because then you have to multiply this by one, two, and three. So, I believe 10 equals one gigahertz. All right? So there’s a tenth difference. Actually, we have so much everywhere that there is a ten megabyte difference here.

Again, if you go and see this, so 00:10 megahertz, et cetera, et cetera, that’s the band we have. Let me show you some examples related to that on the next slide. So you can see that all of these spectral ranges are displayed here. Similarly, there is a distinction between the spectrum and that which is defined as a channel. So suppose for this particular range, that is, 2.4 GHz, starting at 2.412 GHz and reaching 2.484 gigahertz, we have 14 channels. Now, for one channel, what will be the difference? So, for example, the difference will be 2.417, which appears to be very small, but the value is bigfour, one, two, which equals 50 zero. This is in gigahertz. That means that you have 5 MHz. So again, if you multiply by 1000, you’ll get 5 MHz. Okay? These are the calculations we should be aware of. Again, it’s primarily mathematical, with a dash of physics thrown in for good measure. So what about the channels here? You can see the channels and the difference between them.

43. Wireless Basics 02

Let’s continue. So here you can see that you have 14 channels, and in between them, the gap is 5 MHz. Again, if you see the overlapping and non-overlapping channels, you’ll find that there is one condition. So if the signal bandwidth is less than or should be less than the channel width,

So here you can see the signal bandwidth and the channel width. If the signal bandwidth is less, there is no overlapping. However, if the signal bandwidth exceeds the channel width between 1234, you have a narrow channel. So you have the overlap in that case. Okay. So these things should be considered. Again, what’s the concept of phase? Phase means how much shift there is in the actual cycle. Assume that the first diagram shows a 0% shift or zero degree of shift. So that’s where the two lines are showing in parallel. But suppose you have a shift of 30 degrees, 60 degrees, or 180 degrees, then you can check the phase shift. So again, these are purely terms related to physics. Some sort of electrical and magnetic signals Again, we are studying networking. All right. So what are the terms that we are going to use more and more and more?So you’ll find the frequency, the hertz, the wavelength, the channel width, et cetera. So one of the key terms we have is “wavelength.” What is the wavelength now? The wavelength is the length of one cycle.

So the wavelength is measured by the physical distance that a wave travels over a complete cycle. and that will be represented by Lambda. Lambda defined the wavelength. For a 2.4 GHz signal, the wavelength is 4.92 inches. For a 5 GHz signal, the wavelength is 2.36. Okay. So again, this is the mathematical calculation. The length of one cycle is the wavelength. Likewise, how are we going to measure the power? As you can see, our power is measured in decibels. If you see the diagram, you’ll find that the power is defined. This amplitude is defined as the distance between two peaks. There are two peaks, one of which is in the positive direction. For example, one is in the negative direction. So the maximum length in between the two peaks will give you the amplitude. And this amplitude we are going to measure will be measured in either watts or milliwatts. As you can see, new terms and phrases are appearing at an increasing rate. So when power is measured in watts or milliwatts, it is considered an absolute measure. Again, we have one mathematical formula that we are going to discuss about that.But the important thing here is that for wireless land, the power will lie between 100 milliwatts and one milliwatt. And if you convert to watts, that is 1.1 watts, or 2.001 watts. So better to go and measure in milliwatts.

As a result, wireless land will have a power range of 121 to 125 milliwatts. But for other services, you can see that for AM radio station broadcasts, this is 50,000 watts. So you can see how powerful it is. So, for example, 16,000 watts for FM radio is huge power, correct? All right, so let’s focus only on the land side, on the wireless land side. And let’s try to understand the mathematics behind that. Suppose you have three transmitters, transmitters 1, 2, and 3 in the diagram below, and you want to check the relative power between transmitters 1, 2, and 3. So you can see we have one better mathematical formula. We’ll go and check the mathematical formula. So what will be the power difference between t one, t two, and t three? For that, it will be measured in decibels. And decibel is a logarithmic function mathematical formula. Now, if you just completed your graduation in mathematics, biology, or maybe engineering, then it’s very easy and convenient for you to check this formula in DB. So when we say “ten base ten, p two by pone,” that means that this is “ten, log ten, p two.” Actually, divide means p 2 minus p 1.

So you can think like this—it’s not the exact number, say ten. I can count on ten being outside because ten is common. So this means log ten, p two, minus log ten, p 1. And suppose you have a formula, such as p1 into p2. So, plus; that’s the log function we have. Assume you have a formula that goes something like this: log p 2 into p 1. So that means you can take ten outside. This is equivalent to log ten, p 2, plus log ten, p 1. And absolute means that either it’s a plus or a minus; you are taking the magnitude of that or the module of that. All right? So, let us try to understand, and I’ll return to resolve this, what the difference is between power one and power ten. We will not do the difference in power rather than what we can do now. That will go in and measure the DB. Okay? So DB means, for example, if t is two by tone, and then you have log ten, and then you have ten, that means that will be ten. According to mathematics, log ten to the ten equals one. So the difference is ten. Okay, I’ll come back to this. We will go over this further later.

After one or two slides, Let me go and complete the slides first. So then we have three different laws, including the law for zero. Suppose you have the same power, so the relative power difference will be zero, because, for example, ten by ten will give you one, and log ten is the base. One base ten equals zero. Consider the law of threes. Suppose you have a difference of two. So, if you get the value of log ten, base two, you’ll get three DB. as well as one by two minus three DB. Okay, so what does it mean? That is, if you have ten x five and log ten, and you have ten again, you have ten based on ten. This will be logged in to here, and it will come to three DB. This is the formula again; no need to mug up at this point; we can mark this thing as having a value of three. Okay? And one divided by two equals a negative. So this value will be less than three. We’ll talk about it more later in the section, after oneslide. Then we have the law of ten; what does it mean? So if you have ten base ten, that will be one. So one in ten is obviously ten, and one divided by ten is minus. So then you have minus ten. Okay, great. So we now understand the zero, three, and ten laws. Let’s try to solve some of the questions. So here you can see, first of all, we have the summary table. So if the difference is two, then the power difference will be three GB. If one by two minus three divided by ten minus ten equals ten plus ten GB, But again, what does it mean?

So from this example, it will be clear. As you can see at the bottom, the power consumption for A, B, and C is 4, 8, and 16, respectively. B is now how much more than A plus. Okay? So let’s try to understand. Now if you go into B by A, you will find eight by four, which will be two as per the formula. Please inform me that Logan is two, and two equals three GB. As a result, B equals A plus three DB. What will happen now? Again, 16 byeight indicates that two C will be B plus three DB. And if B is A plus three DB plus three DB, that means A plus six DB. Okay, so this is the way that we can go and calculate. If I have some complex calculations, you might think this is a very simple example. So, for example, in this diagram, you can see that you have five and 200. So how can I resolve this? So what we can do in this case is that you can go and check—sorry, divide by five—200. So, how much will that be? 40. This 40 will now be included in the calculation—two into two into ten, correct? So two means three DB plus three DB plus ten hat we can So that means that E is equal to six plus ten. So e is equal to d plus 16. So little mathematical computation If you do, then you can go and check the relative power between two of the transmitters or two of the antennas. So this fundamental understanding is required before we can learn about other wireless technologies. So what is DB? What is the meaning of pain, amplitude, and wavelength? Etcetera. All right, so

44. Three Spread-Spectrum

We have three modulation techniques that will fall under the three-wavelength category. We have FHSS (frequency hopping spread spectrum),  DSS (direct sequence spread spectrum), and OFDM (orthogonal frequency division multiplexing). You can see that the name itself is big, and we are going to discuss exactly where they fit in the wireless LAN and which standards match which particular spectrum, right? So if you go and check the technical details, like the physics and the electronics behind that, you’ll find that there are so many things to understand. To understand one spectrum behind the scenes, It has a complex mathematical and physical structure. So we take those things and use them in our digital world, in our networking world. So let’s see what exactly we are using. Although most of the engineers are using wireless technology, we are not aware, behind the scenes, which particular spectrum of the modulation technology we are using. with which particular standard? Ita standard.

So first of all, we have the FHSS, which are the early ones with the evolution of wireless land technology; we have this methodology; we have this modulation technique; and we have this spectrum. So here you can see that it has 79 channels, and you have problems as well. And we have some benefits as well. So what is the problem here? You can see that the frequency hopping will follow this rule. So channel two will move to 25, then 64, then 10, then 45. Like that, it will jump. Now here in the diagram, you can see that first of all, it is supporting 2.4 GHz spectrum, and then you can see in the diagram that two, then it is going to 25, then 45, then 64, returning back to 10 and vice versa. Now, what is the problem? The problem here is that they are limited to a one- or two-Mbps feed. That’s one of the big problems because nowadays we are looking for speed, and this is one of the biggest problems. Now, what is good is that whenever we are talking about fast-evolving technology, it’s actually easy to set up and use, etc. Now all other technologies, such as modulation technologies, are also easy to set up and use. But behind the scenes, the circuit, the chip, the encoder, et cetera, are a little bit complex because they have evolved from one technology to other technology.

So what is the solution? So then we have the next approach, a spectrum approach, which is DSSS (direct sequences spread X spectrum). It can give you higher throughput. So, for example, by the end of this slide, we have on some slide. So we’ll see that.So it is going to give you, for example, eleven MPs of speed. That is still not enough. Correct? This also falls within the 2.4 GHz band. As you can see, FHSS and DSSS are both in the same spectrum band. Their overall throughput speed is Although eleven MPs is good, nowadays we are working in a digital workplace, after all. It is usually less than the other disadvantage. that because the channels are overlapping. So they have only three non-overlapping channels. Channels one, six, and eleven Now, what is the technology behind it? So, let’s try to understand. This technology, this diagram, can be seen here. This is how the bids are arriving. They are getting cod, which means they are getting arranged again. They are getting packed inside the block. And then it is getting modulated, and then it is going outside as a signal. So, how’s it going? So first of all, we have the scrambler, what it is doing, and the data waiting to be sent in. First scrambler. Whenever any request is made, it’s up to the scrambler; it will do some scrambling and then decide how the data will go. Now, next is the coder. And it’s important what the coder is doing—they are converting data into multiple bits. The coder’s job is to convert whatever data there is. So you can see that the database is coming. The coder then converts that data into multiple bits. Each of the newly coded bits is referred to as a chip. So here you can see in the diagram that all these bits are called a chip. Now, here we have DSS using encoded technology.

So you’ve probably seen this abbreviation somewhere. We have Barker codes and complementary code keying (CCK).That’s a coding methodology. Now, next, we have the interlocutor. what the interleaver is doing. Again, whatever input you receive must be of high quality. So, obviously, the data bits from the coder will be spread into a separate block by the interleaver. So you have data, then bits, and finally block data, bit block. Finally, we have the modulation. The modulated signal will then be broadcast into the air as an RF signal. Now, more or less, the DSS and the next technology, that is, OFDM, both use the same technology behind the scenes. But in DM, you can imagine that you have parallel processing. So suppose that DSS or DT Plus have this modulation technique for one stream of data. Now, if you do 64-bit parallel processing (for example, 48 plus four parallel processing), obviously your overall throughput will increase. So, suppose you have 11 Mbps and can multiply it by, say, 52. So the next technology we have is that much throughput in terms of MVPs because we are still looking for higher throughput and speed. So we have the OFDM modulation technique. What OFDM does is aid in parallel processing. That’s the main thing. So here you can see that, in contrast with the IFTMsends database running in parallel, that’s the key over multiple frequencies, all contained in a single 20 MHz channel.

Now there is technology. So they have guards for twelve subcategories, pilots for four subcategories, and data for 48 subcategories. Guards will be present, but this pilot and 48 subcategory for data will be used. You may believe you have that much parallel processing or that many parallel signals in a row. There are so many here that you can see you have 48 subcategories. and that’s huge. Correct? Great. So you might see that frequency again now and then; these are the theoretical things. Having 52 subcategories, 48 fields, and four palettes This is because the twelve guard frequencies are not actually transmitted but are silent in the channel spacing. As a result, the modulation for each data point is repeated 52 times. So you have 52 times as many subcategories. Let me go and show the diagram. So here you can see in the diagram that you have coordinated data. Then you have 48 subcategories. You can see inside the subcategory, and then you have the channel. So you have a 20 MHz channel, and it is spread across 48 subcategories. Now, of course, they have to use scrambling, coding, interleaving, and modulation, but for all subcategories. And that’s why it’s parallel processing. So whatever we studied in DSSis is having the same effect. Say, for example, 48 times in parallel.

45. The 802.11 Amendments

We have it. AAA. Standard. So let’s see that. First and foremost, we have 802.11, which was introduced in 1997, and then 811, which was introduced two years later. It supports the 2.4 GHz band, as seen here. The modulation is duplex, and the data is supported up to eleven MPs. Now, eleven MPs is not a big deal nowadays in the digital world. So that’s why we need some higher throughput. So next we have eight two-point-eleven GHz, which are also in the band of 2.4 GHz. However, the data rate here begins at six MPs and progresses to 54 Mbps. As a result, it provides significantly higher throughput than the 802.11-B interface introduced in 2003.

The problem in this eighty-two point eleven G is that, while you have bands, they are different bands. So we have a note here that G and B used completely different transmission types. One is using DSS, and one is using DM. And we discussed these technical details in the previous section. As a result, because they use different communication channels and signals, the devices that support these transmission types will not communicate. Okay. And the other thing is that they have a very limited non-overlapping channel as well. So that’s why we have 80, two points eleven (A). although this will also support 54 Mbps. But it is using a different channel; it is using a different band, the 5 GHz band. But it has a long range of non-overlapping channels. So here you can see that the band is different for a two-point-eleven A, which is the five-gig band, and the speeds range from six Mbps up to 54 Mbps. At this point, we can still see that 54 Mbps is not what the digital workplace is looking for, because Lansing now has 100 Mbps.

We need fast throughput. We have different types of devices in the workplace. We have IoT-based devices, we have many mobile devices, and we need faster speed. So that is the evolution of the introduced two points eleven N that supports 600 Mbps. That is the theoretical maximum. But it is supporting a huge amount of bandwidth.

The data rate is huge, and they also have very few overlapping channels. The good thing about this is that you can see in the summary that they are supporting both bands 2.4 and 5. So in this list, we can see that we have two-point-eleven, where we have both DSS and FHSS. We have a story about this in our previous section. This feed was two MB. After two years, eleven B came into the picture, whose modulation is D TIPAla, which is supporting eleven Mbps. Then we have eleven A, which is using TM at 54 Mbps. But you can see the band is different. So there are eleven A and eleven G. You can see the band is different, but they can have the same modulation technique. And their overall throughput is 54 Mbps. Now, in 2009, we have 82 points eleven and where they are supported, both bands, the bandwidth you can see the modulation is OFTM, but the theoretical throughput is 600 Mbps. Alright, so let’s stop here.

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