Student Feedback
220-1001: CompTIA A+ Certification Exam: Core 1 Certification Video Training Course Outline
All About the CompTIA A+
Book Chapter 1 - Safety and Prof...
Book Chapter 2: The Visible Comp...
Book Chapter 3 - CPUs
Book Chapter 4 - RAM
Book Chapter 5 - Firmware
Book Chapter 6 - Motherboards
Book Chapter 7 - Power Supplies
Book Chapter 8 - Mass Storage Te...
Book Chapter 9 - Implementing Ma...
Book Chapter 10 - Essential Peri...
Book Chapter 11 - Building a PC
Book Chapter 17 - Display Techno...
Book Chapter 18 - Essentials of ...
Book Chapter 19 - Local Area Net...
Book Chapter 20 - Wireless Netwo...
Book Chapter 21 - The Internet
Book Chapter 22 - Virtualization
Book Chapter 23 - Portable Compu...
Book Chapter 24 - Understanding ...
Book Chapter 25 - Care and Feedi...
Book Chapter 26 - Printers and M...
All About the CompTIA A+
220-1001: CompTIA A+ Certification Exam: Core 1 Certification Video Training Course Info
Gain in-depth knowledge for passing your exam with Exam-Labs 220-1001: CompTIA A+ Certification Exam: Core 1 certification video training course. The most trusted and reliable name for studying and passing with VCE files which include CompTIA A+ 220-1001 practice test questions and answers, study guide and exam practice test questions. Unlike any other 220-1001: CompTIA A+ Certification Exam: Core 1 video training course for your certification exam.
Book Chapter 3 – CPUs
4. Installing a CPU
There are few things more gratifying in this nerd's world than a brand new motherboard and a brand new CPU. I love the smell of new electronics in the morning. Anyway. So what I want to do in this episode is talk about installing a CPU. Now, before we get too excited, a big part of installing the CPU happens before you even buy anything because we're going to get all interested. Maybe you're into Intel CPUs; maybe you're interested in AMD; maybe you've read some reviews in terms of price per hour that indicate AMD is the hot thing. Maybe. Intel has been going back and forth for decades. As a result, it becomes a major debate. Right now, I'm a fan of AMD, okay? So I bought myself an AMD motherboard. Now this motherboard ended up subtitut terribly. Well, it's actually incredibly exciting to me. But before I bought this board, I went ahead and had to do some things. For example, I may have had a particular CPU in mind. So I want to buy a motherboard that first of all,it had to be an AMD motherboard if I wanted tobuy an AMD CPU interchange between AMD and intel folks. But maybe there was a particular CPU that I really liked. And in this particular case, I've got an AMD Ryzen processor, and I wanted to make sure I got a motherboard to support that. So there are a couple of things that I'd be looking at. All this uses an Am four-pin socket. So I wanted an AM4 four-socket motherboard. And one of the most important things you'll ever get is the Motherboard Book. So this motherboard and I'm looking at this thing, ormaybe I'm looking at online resources, and I want tosit there and see what exactly can this handle? So the first thing I'm going to lookat is it's an Am four motherboard. In fact, it even says so on the outside of the box. That's great. But the other thing I'm worried about is speeds. So I'm actually looking at the documentation to see how fast of a CPU this particular motherboard can handle. There are A4 four-socket CPUs that would be so fast that this motherboard couldn't handle them. So this is exactly what you want to look into. You're usually buying the motherboard and the CPU at the same place at the same time, and usually you've got a salesman right there going, "Okay, so you want to use this rising here on this particular board." You're in great shape. So that's literally how we go about that. Now, once I'm assured that I've got an acceptable CPU for this particular board and vice versa, it's time for me to start putting things on here. So first of all, let's take a look right here at this socket, which is number 4. Now this is what we call a zero insertion for a socket. And they're all fairly certain in that there's some kind of bar that we lift up, and it makes it ready for us to drop in a CPU. So that part is pretty straightforward. So what we're going to do hereis we're going to grab the CPU. Oh, by the way, I own all this equipment, so I'm not using my static tools. If you are doing this in a professional environment, you'd probably want to consider using an anti-static wristband. So I'm going to go ahead. This is my rise in price. I'm going to make it look pretty. So what we're going to do is drop it. Now, even if I had anti-static tools on me, I'm going to be really careful about how I touch stuff. In particular, I don't even want to graze my finger against these tiny little pins. So we want to be really careful here. Now take a very close look at this processor, and then look at the ZIP socket next to it. If you look, there are notches in the corners here. All CPUs have an orientation, and they're only going to drop in one way. The problem is, these pins are so fine that you want to try to get it right the first time or so. Now, I can see here; I don't know if the camera could pick it up, but this is kind of like a triangular notch. That's a triangular notch? That's a triangular notch. But this one's a little square shaped.So that's what we call the orientation notch. And if I look here at the socket, I can see a square notch right here. So I know that this one has to line up in this corner. Boom, it dropped in. Now, if a CPU doesn't go the right way, it's usually pretty obvious that it's got a little skew. It's not going to feel like it's dropped in easily. A lot of times I'll hold it up from the side to make sure everything's nice and flat. But that's really all there is to installing the CPU itself, popping it in, making sure everything looks good, and then closing the arm to lock it in. So that part is pretty easy. Now, the problem we have with any CPU today is that it generates phenomenal amounts of heat. so we're going to have to put some kind of cooling on it. Now, what I have here is what we call an OEM CPU. On almost all these OEMs, I pulled the CPU out, but they pretty much all come with a fan. So we tend to call these OEM fans. OEM fans are nice because AMD made this fan themselves, and they guarantee me that it will provide sufficient cooling for this particular system. If skews are simple to add, fans are more difficult. It appears that the industry changes how you drop in a fan every few years. So it can be a bit challenging. So as I pull this up, I'm going to be looking at some fun pieces here. We'll set this off to the side since it's probably going to be powering the fan itself. And what I want you guys to look at is right here. Look up on this What you're looking at here, folks, is called thermal paste or heat dope. I can actually smear it around a little bit. This is actually used as a barrier—well, not necessarily a barrier—as a way to pull the heat even better from the CPU to the cooling system itself. Let's take a look at this cooling system while we're at it. So we got everything just right. We've got all these cooling fins, and then there's a fan on top. So that's pretty straightforward. How do you get these fans on? I mean, it literally changes all the time. You can read the instructions and try to figure it out. Or you can be like me and just kind of cowbong it. So that's me, Mr. Vegas. So I'm going to go ahead and put these on. I can see two notches right here that correlate to two pins on the sides. So let's just drop that in and see what happens. looking for any type of orientation that tells me it goes one way or the other. So I dropped it in on one pin. These things are always tight. Always tight. So I've got one end over here, and I've got to lock it on this guy. There's a lot of tension in these. And this is typical, in fact, of a well-placed fan. Do you see it's hooked over on this end as well? So, yeah, it took a little force. even had to bring in a pair of needles. No, that's okay. In fact, a well-mounted fan should be incredibly tight, like this. There are a lot of guys who are into performance and will do stuff. For example, they'll scrape that thermal paste off, and then they'll polish the copper to the point where it looks like a mirror. Then they'll get their own thermal paste and reapply it. There are all these little tricks people can do. In fact, if you really want to scare yourself, check out something called "Deliting." That's where they literally take the metal cover off the top of the CPU, and then they fill it with stuff, which is absolutely terrifying. I don't do these things, but here's a good way to test to make sure that your fans are mounted well. I would never, ever consider a fan well mounted if I couldn't easily pick the entire motherboard up by the fan itself. So this is a good tight mount, and it's always a little tricky when you have to use a lot more force than you're used to. Fans are always a problem with that. This is actually a pretty easy installation. I could show you some Intel fans where you have to use these crazy little screw things. It's different every time. So one thing I'm going to do right now is pick it up, and I just want to see if it looks level. I want to see if everything looks like it's mounted tight and if I caught anything. Your eyeball is about all the test you'll need to confirm whether you're correct or not. and as I look, it looks really good, and I'm pretty happy. Now this fan needs electricity, and that's what this little connector is all about. So you're going to have to look around on here and find that there's usually a little connector that says CPU fan. So this is actually here to provide power to the CPU fan. All motherboards are going to have this now. So it's a four-pin connector, and I'm just going to drop that in. Mike Myers, the popular computer guy, still has trouble and always has trouble getting these things in. There we go. You put them in backwards. There's a small guide in there; make sure they're in there. Now I want to be sure of these other types of connectors. Right now everybody's excited about RD, and basically what that means is we can light up this fan with all kinds of beautiful RGB LED lights. Now I'm not against them, although they can be a little irritating at times. But if you want to use those in particular, AMD is always going to provide a little connector like this for you to put them on. I'm going to skip them for right now because I'm not a big fan of the lights, but that's basically your set. In order to test this, we're going to have to buckle on a few more pieces. So for right now, let's just hang tough and accept that that's what looks like a really nice installation for my CPU.
5. Liquid Cooling
CPUs generate a lot of heat. And one of the things in tech we like to do is come up with alternatives to the OEM fans that come with our CPUs. Pretty much any Intel or AMD CPU is going to come with a fan made by AMD. That's guaranteed to work as long as you're not doing anything weird now. Nerds—well, we like to do weird things. Weird thing. Number one, we like to overclock. We like to push our system at its rated speed. And number two: fans make noise. Fans are noisy. And if it makes fans less noisy, I'm going to go for it. So one of the tricks we like to do is use something like this. So this is a fan. This is made by a company called Cooler Master. These are really, really popular fans. They're designed to take out more heat, and they do a really good job at it. You can find a lot of different kinds of fans out there. You can also get fans that don't necessarily have more heat, but they just have much bigger fans. And the idea is that they can turn, so they're quieter. But if you really want to be a cool kid, you're going to do something like over here.What I've got in this case right now is a very simple but incredibly effective liquid cooling system. So if you take a look right here, I've got a big chunk of metal inside. This metal coolant, which is basically water with a little alcohol in it, runs through a bunch of little veins. I can't show that to you without destroying it. It's all a sealed system. You'll notice that there are two hoses here. So one hose is pulling away hot fluid and bringing it into here, which is cold. These two fancy things serve as a radiator. I'll show that to you in a SEC. And the other one returns cool fluid and returns it here. So it's a very liquid cooling system. Let me take this off so you can actually see the radiator. Be careful. Things might go bang here. So if you take a look, I've got some wiring in here. Oops, I dinged it already. So this is just a regular radiator, pretty much identical to those you see in automobiles. And what's happening is all that hot fluid is going through all these different veins, and the fans are blowing air through it and cooling it off. Liquid cleaning is absolutely amazing. Number one, the big reason I like liquid cooling is it quiet down. Yes, I have some fans on there, but I can only turn these fans at a very low rate of speed. So the system becomes almost silent. And I like quiet computers. The other big advantage to liquid cooling is that if you want to turn the knob up a little bit, it can yank out a tremendous amount of heat. Because when you're overclocking CPUs, they generate even more than the rated amount of heat, and you need something to pull all that heat away. Now, this is a very simple system. If you want to go crazy on liquid cooling, be my guest. You can get systems that will cool the CPU. They'll cool down your video cards. They can cool down your hard drive. You can build all your own custom stuff with your own custom radiators and hoses. And you can even make clear little hoops with little sparkly bits of gold in them. So everybody thinks you're really, really cool. But understand the benefits of liquid cooling. Or, number one, it makes your computer quieter. And number two, it draws more heat away than any fan could ever hope to do.
Book Chapter 4 - RAM
1. RAM Technology
If you're going to have a computer, you're going to have some RAM in it. So, in this episode, I wanted to discuss the various types of Ramtechnologies that have been developed over the years. Because I want you to understand what you're buying in the board or selecting a system in order to get the type of RAM you require for your computer. So take a look. What I've got here in front of me is a bunch of RAM technologies that span a number of years. And what I'd like to concentrate on is this stick of ram right here. This is, as far as I'm concerned, the original RAM. This is known as synchronous DRAM, or SDRAM. There was a Ram before this, but it was the Ram of your forefathers. And I don't want to talk about it. It's not on the exam. Find a computer that still uses that agent, Ram. Well, it's probably going to be in a museum. So anyway, SDRA is interesting because in other episodes, we talk about the system crystal that sets the metronome for PU. Well, synchronous means that it's synchronised to the same crystal. And that's very useful because we can rely on this stick of Ram to do something at any given time. So SDRAM was the first one out of the box. Now, what's important for me is that, as you just stick with Ram, there are a couple of things that I want you to notice. Number one, this is 168 pins. Got them real quick. Oh, I'm kidding. But what is very important is that you'll notice that there are two notches. SDRAM sticks are the only type of RAM out there that has two notches that you're going to run into anymore. Now, SDRAM runs fantastically well, but just like your CPU has a speed, your SDRAM has a speed. So when we talk about SDRAM, we talk about the speeds associated with it. So with SDRAM, it was just running at whatever your motherboard speed was, which was 66. Whatever it was, that was just the speed associated with it. We're going to see that this gets a little bit more complicated as the technologies improve. So the first big leap forward from DRAM is this stick right here. This stick is known as double data rate (DDR) SDRAM. But most of us will just say DDRM. DDR double data is the clue. Basically, for any one given click of the clock, this would give us two bits of information, which was a huge breakthrough and really sped Ram up a lot. Now, the problem we're going to run into is, how do we define that speed? Because when you're going to buy RAM, your motherboard needs RAM at a certain speed. It's in the Motherboard Book. So when you go to the store to buy your RAM, you need to make sure that you have those speeds. And that's where we come into the DDR or P ratings. Let me give you an example of this for DDR. Here are some examples of DDR speeds that we used to see. So you'll notice on the left we have a clock speed. And this is basically the speed of the motherboard itself. The speed ratings, or DDR speed ratings, are known as such: it will say DDR, then a dash, and then some speed. Now, if you look closely, it's pretty straightforward. All you have to double it. It's a double data rate. That makes sense. Now, the next thing I want you to look at is the PC speed rating. You can see either one of these when you're buying RAM. It's going to be printed on the RAM stick, or at least in the box you get it in. The PC Speed rating simply measures the same speed, but in bits rather than bites. So just take the DDR rating, multiply it times eight, and you get the PC rating. Pretty straightforward, right? Fantastic. DDR was a huge breakthrough. And it's really important to me that you be comfortable with the DDR and these PC ratings. In fact, you're about to see a few more of these as we progress through.So time marches forward, and let's go ahead and get our next generation. And this DDR is no exception. Now, forget the metal cover. To me, these metal covers are called heat spreaders. I think they're more sales than anything else. That's my opinion. But what's important—and you've got to look very carefully—is hard to catch this.So if SDRAM used 168 pins and DDR used 184 pins, the nose was only a single notch. DDR Two uses a 240 pin. And it looks like the notches are in the same place. But if I put them right next to each other, notice the subtle offset between those two notches. Be glad for that. The idea is that one particular motherboard is going to use one particular technology of RAM, and they don't want you to accidentally put DDR into a motherboard that needs DDR. So we're glad that the notches are a little bit offset. DDR-2 really set the standard for RAM systems, and it had a long, long lifespan. It also had some speed ratings. Let's take those. So here's a table of common DDR 2 speeds. Now, keep in mind all these tables. I don't list every poppy that would be 40 feet long, but these are the more common ones. So once again, we look at our speed, which I call the motherboard speed, and you'll see that's the speed of the system crystal itself. Now, with DDR, it goes ahead and does the double, as I mentioned before. But with Dark Two, it actually doubles a second time by using this interesting function you call a prefetch. But the bottom line is that DDR2 was really four times faster than regular SDRAM, twice as fast as DDR. So if we take a look at this First of all, when you look at the speed ratings, again, these are printed on the boxes. When you buy RAM, notice the DDR 2. The actual DDR Two rating is goingto say DDR Two on the box. On the box, when we're talking about DDRTwo, you'll see it says PC Two. Then, take whatever speed you have, look at the third column, multiply by eight, and you'll have that PC rating you've always wanted. Remember that it's on the exam. So it is important if I'm holding two different sticks of Ramand and I don't have the notches memorized, so I can't tell them apart, and the sticks don't say DDR or DDR too; all I need to do is look at that PDC rating. If the PC rating says just PC, then we know it's DDR. If it says PC Two and then a dash, then we know that it's DDR-2 just by looking at the speed rating. Fantastic. Let's go ahead and keep marching on. Now, what I've got right here is DDR 3. Yep. DDR Three once again doubled the bandwidth of DDR Two and created some wonderful bandwidth. Now, again, if we look at the sticks very, very carefully, by the way, DDR Three uses a 240-pin stick just like DDR does. But again, can we catch it on camera? It should be more obvious this time. We can see that the slots are very far apart, preventing you from accidentally inserting it into the wrong motherboard (DDR-3). It didn't have that long of a lifespan. It was around for a while. but it also has some much faster speeds. Let's take a look at those. So, at this point in the game, I'm hoping you're kind of used to looking at the table. So on the left, once again, is our core speed. Notice that the core speeds keep getting faster and faster. Technology marches on. Motherboards are getting faster. So the actual DDR I/O speed is going to be four times that in this case. So what we DDR is actually doubling once more. So our speed rating now—look, this is very important. See, it says DDR. Three CTC, three? That's how you know the speed rating defines the actual technology of RAM. Just because it says PC, just because it says DDR 3, we instantly know that we're talking about DDR 3 memory. And all you have to do, once again, is take a look at the top one where it says DDR 3800, multiple times eight, and you get the actual PC Three speed rating. People will say to me, Mike, why are these two different speed ratings so important? Well, the answer is pretty simple. because RAM makers will use one or the other. When you actually look at the box itself, a lot of them are using both whenyou actually look on the box itself.but I can't guarantee it. And I want you to be able to go into your computers and order the right stuff for your system. The motherboard book itself is going to use these to tell you what kind of RAM you need. So be comfortable with this terminology. The last type of general purpose RAM I want to talk about is DDR-4, and I've got it stuck right here. Now. DDR four used 288 pin stick. And again, this one, as you can see, is well offset from anything else. There's no question that these are different types of technology. DDR-4 is the RAM that's described on the Comp Tia A+ exam. And it's currently by false common. It's probably going to be around for a while. DDR Four has some outrageous speed. Let me show you those as we take a look at the speeds here with DDR 4. First of all, if you look on the left side, these are the motherboards. They're getting faster. But this time, as opposed to the other tables, we tend to use the term band when we're talking about DDR Four.So what we're talking about is MT per second. We're talking about mega-transfers per second. That is, the actual amount of data being moved, rather than just the number of clock clicks. But we still have our DDR-4 and our PC rating when we're talking about DDR Four.When discussing speed ratings, the terms DDR-4 and PC-4 are used. Like any other type of technology, RAM has been improving over there. What's important for you is that when you're picking a particular motherboard, that motherboard must use a particular type of technology. The newest technology is used in the newer types of boards, but there is plenty of room for older technology, Ram. You'd be surprised how many big laser printers or dedicated systems still use older RAM. Check out any electronics store you see. You can still buy DDR 2 today. So make sure you're comfortable with the different types of technologies. Make sure you're comfortable with the pin counts, and make sure you use the right RAM for your system.
2. RAM Capacity
Every stick of RAM stores a certain amount of data that we can use. Now, you can't just look at the chips or anything like that to give you an idea. And whether it's DDR, DDR two, or DDR three, that has nothing to do with it either. That's just speed. So when we're talking about the capacity of RAM, it's actually kind of fascinating. The Ram chips, the way their internalorganization is, is based on a square. So in this particular example, I'm holding a piece of RAM in front of me that is 256 megabytes, which in today's world is incredibly small just because of the way RAM is manufactured. When they make a bigger chip, they tend to, because it's a square, double each side. So if you think about this, if this is 206 and it's a square, when we double each side, we're, in essence, making it four times bigger. So the next step for Ram is going to be one gig. And then, from there, 16 gigs. Get the idea? Now, when we talk about capacity, we're going to say things like one gig, four gigs, and 16 gigs. However, you can on Ram, that's going tobe like 512 meg, two gig, eight gig. That's only double. And they do this by doing something very interesting called double-sided sided Ram.So if we take a look at the stick I've been playing with, if we flip it over and look at the back, there are no RAM sticks on it. So this is going to be a single-sided stick of ram. However, if we take a look at this guy righthere, you'll notice that there's Ram on both sides. Double sided fix are very, very common. The only downside to double-sided RAM is that there are a few motherboards out there that might have a problem with it. So one of the things we always want tocheck is we want to look at the motherboardbook and verify that it uses double sided Ram. Okay? Now that we understand the difference between single-sided and double-sided, the next thing I want to talk about is our channels. So I want to look at this motherboard here right in front of me. Take a look at this. We've got four slots where I can snap in. Now, that's pretty common on most of these desktop motherboards, that you have these four slots. However, let me show you another one. And in this case, you're going to notice that it has two slots. In fact, there's a motherboard out there today that could have eight or even 16 slots on big server systems. The reason we have so many slots is because we want flexibility in terms of our RAM. In general, when you're inserting Ram into a motherboard, youcount all the Ram up, and that's your total Ram. So if I put in two 8-gig sticks, this system has 16 GB of RAM. If I put in four, eight-gig sticks, then this system is going to have 32GB of RAM. However, we do something that's known as channeling. If you take a look at these, look at all three of these boxes. Now, if you look at this, you'll see they're soldiers. There are two in here. Trust me, even with this one, you can actually buy two RAM sticks. RAM is almost always sold in pairs these days. The reason they do this is because pretty much all motherboards use this concept called channels. So if we zoom back in on this big motherboardin front of me, what we're looking at is avery common situation where we have today dual channel memory,which means I have to put two Ram sticks ofthe exact size and hopefully speed into very specific slotsin order to put those channels are. It's always a little bit of fun. So I had to dig through the Motherboard book. I'm actually going to see if we can bring this up on the screen. So first of all, we have a little diagram that orients us to this motherboard right here. So I'm sure it's 90 degrees, but we can figure it out. If you take a look right here, it tells us that these two that are closest to the CPU fan are channel A, and the two further away are channel B. If you want this computer to run as fast as it possibly can, you will put two sticks of RAM in it because it's a dual-channel motherboard. Dual channel is really common these days, even in triple channel, where you always had to put three sticks in. But it was the motherboard that told you what to do. Using channels makes some amazing stuff happen. In fact, when I'm talking to the Ram, when I'm using channels, I can literally talk to both sticks of Ram at once, as though I had this huge, monstrous, super fast piece of Ram. Now, on a lot of motherboards that require dual-channel memory, if you try to put one stick in, it won't even boot. In a particular case, he's showing you a situation where you can put in one stick of RAM and it will work. But I need to warn you right now: when you boot this thing up, you're going to get a big error thing.It's going to say running-angle channel mode, which is actually telling you that you're not taking advantage of the power of this motherboard. So let's take a look back at you. If you're only going to put in two sticks, you have to put them in two very specific slots. Don't put them in the other two. Don't try any other combination. The computer probably won't boot up. And if you want to put in four, well, that's easy. Just fill them all up. The only other trick with channels is to make sure that you're putting identical RAM in any given channel on any given channel. You want to make sure they're the same speed. You want to make sure there's the same capacity. That just has to happen on a separate channel. And you could do this, although I personally don't like to do it. You could install different-speed RAM. I would recommend against it. Some other boards are stuffy about it. I'm really persnickety about using the same speed across the board. However, what I can put on that different channel is different, so I'm not. However, that starts to make for some interesting counting. So you're ready? Play along with my mic. So let's say we're going to go ahead and put two sticks of 8GB RAM in here. So according to the motherboard, we snap it into these two slots. That's going to give us a total of 16 gig of RAM. Now, you don't have to put the same capacity in the other channel. So let's say we put in two, four gigs, anotherone, that's a total of eight gigs of Ram. So 16 plus eight means I've got 24 gigs of RAM on this system. So if we take out the two eightes and put in 216s, remember, they have to be identical. We now have two plus eight, which equals 40 gigs of RAM. This creates some really interesting scenarios. Like, say I've got a motherboard that only has one channel on it and two slots like the one we just saw. Assume it contains two four-gigabit sticks. In that case, the total capacity of that system is 8GB. So somebody comes up to you and they go, "Hey, Mike, I would like to add more RAM to this computer." And you have to tell them that, well, in order to add more RAM, there are only two sets. So we're going to have to taketwo sticks out and put more in. That always confuses people. They're like, Why are you giving me Ram back? I just wanted to add more. The answer is, you only had two slots. So, when it comes to Ram, be cautious of your capabilities. Understand that you have a certain number of slots and a certain number of channels. Motherboards are almost these days,almost always dual channel. And remember, more than anything else, the motherboard is the key. It will always tell you what to do to make your system work properly.
3. RAM Features
Let's consider in this video one of the most popular types of network topologies, and that's a star topology. And we commonly see an Ethernet switch as the central point of that star. And then radiating out from that central point, we've got different network devices, such as a laptop. We might have an access point for wireless communication. We might have a printer or an IP phone. And the Ethernet switch sits in the middle, and it kind of looks like a star. However, this is not the only device that we might find in the star topology. Before we had Ethernet switches that were widespread, we had Ethernet hubs. Now, a hub is not nearly as intelligent as an Ethernet switch. It doesn't do a great job of forwarding traffic. You send a packet into that Ethernet hub, and it just regenerates it out of all the other ports because it doesn't really know where it's supposed to go. And even that switch is much better. The laptop is talking to the printer. We send the packet into the switch, and the switch knows that this printer lives off of this port, and it only sends the packet where it needs to go. But back to our discussion of the topology, there are a few characteristics I want you to know about a star topology. First, if one of the links were to fail, that wouldn't impact the other links. If the laptop link were to go down, the access point, the printer, and the IP phone would continue to function. That's not the case with some networks, such as a bus topology. Perhaps we were using ten base two or ten base five Ethernet technologies in those networks, and we had an end user device that tapped into a coaxial cable. And if that coaxial cable were to fail, or in other words, if that link were to fail, every device connected to that coaxial cable would also fail. But here, a single link failure does not bring everybody down. But that's not to say there's not a single point of failure. That central point of the star and the Ethernet switch In our example, that is a potential single point of failure. Because if that switch goes down, what happens to network connectivity? For all the devices we talked about, they don't have a way to get to the network. That's why, in high-availability environments such as a data center, we might have a server with more than one network interface card for redundancy. One network interface card might connect to one Ethernet switch, and another network interface card might connect to a different Ethernet switch again for redundancy. That way, we could lose a switch and still have connectivity out to the rest of the network. However, with most user-facing devices, such as a laptop, that's probably going to be a single point of failure. And there's one more thing you should remember about star topology. We've already mentioned that it is very popular in modern networks in the form of an Ethernet switch.
Pay a fraction of the cost to study with Exam-Labs 220-1001: CompTIA A+ Certification Exam: Core 1 certification video training course. Passing the certification exams have never been easier. With the complete self-paced exam prep solution including 220-1001: CompTIA A+ Certification Exam: Core 1 certification video training course, practice test questions and answers, exam practice test questions and study guide, you have nothing to worry about for your next certification exam.