Alrighty, so many different classes of ipv4 addresses, right? You have an idea already, how to solve it, right? We had that host address, the subnet mask. And then we figured out the range. So we know more or less that concept of drawing the line or have you finding what we increment buys, we can figure out where do you Hey, where do you fall in what range what network, which broadcasts, right? So here, it was easy, because it was classy.

Here, you want to have a class A, this will be your starting point. And then we'll do the same thing for all them, but just on different classes. Okay, we need 3000 hosts for mass with us. That's a legit question. You can see on exam, you can send an interview. And what's really cool though, you'll go Oh, you need how many 300,000 house Okay.

Oh yeah, you need this helmet. You need this mess. You blow their mind. Okay, because that's seriously, I'm serious. It's not serious. You can do this in your fingers.

I am not kidding. Okay? I'll be going on the interview, just write it down. We'll make him feel that bad. All right, because then they won't hire you because you don't wanna. Ah, then we're gonna do a Class B, or you need 400 host.

That's easier to count to the six by 12. Done. Go 23 Well, see how quick that's how you got to be. That's how you got to be. There's got to be a bit value in your mind right there. Yeah, just forget about the ruler.

You gotta have a bit value thing. 128 6432 60 you gotta have it. And also you can find you can find these addresses. Okay, quick, quick, quick, quick. classy. Really?

30 Host watch. I said fingers. I waited for the last one because I know it's alright. 248 1632 as soon as 30, there's 35. I'm five bits that are off three bits that are on the 27 for two to four. I know that bit table, but it doesn't.

You see? That's it. That's how I want you to get. I know you guys can do that. I know, I know. We have calculators out there, but believe me, a real world scenario.

You guys have spreadsheets, but and they're writing things down and they have calculators and all that, but it's so easy to just do it. You know, I can see you're doing ipv6. Yeah, man. There's so many freaking numbers in that thing. Okay. But for ipv4, come on.

Alright, so anyway, let's stop talking. Let's go ahead and figure these questions out CSI. Alrighty, welcome back. So now like I said, we're going to do different classes, or IP addresses, right. So we're inside the lab. Now we've talked about this a little bit.

So again, we got to follow the concepts that we learned in the previous lecture. Okay? So okay, we have a class A address here says 1016 is our starting point, right are 1016 00 12 you need 3000 holes, what mass would you use? Okay. So let's break this down into binary. Well, we know the X has eight bits in there.

So that's completely on, right? Because what is this, we learned that in conversions, to five, five, right, that's a bit, we need four more bits, right? For 12 910 1112. Okay, so that's 249 00. Okay. That's what that 12 represents.

Okay, so that means that we're working on the second octet, and we have 1234 bits on and we're going to draw a line right there. Okay. And then we have the other bits are off 1234 dot 12341234. That was 12341234 All right, so there are four octets, right one, octet, two octets, three and four. Okay? But we're focusing on the second octet.

Now remember your bid values and said no, here's we got some space one. Now, one 148 6432 16 a four to one, right? So 128 so we got 120 864 3216. Haha 16. Okay, we're incrementing by 16. Okay, and Okay, big deal.

What's the question? You need 3000 hosts? Oh, okay. Well, we have a lot more than 3000 hosts here, don't we? So right here we are cs 5136. So I'm actually gonna keep calling this way.

So it's okay, we need me 3000 holds Let's count by two and double as you go. from right to left 248 1632 64 128 256-512-1024 2048 wall comes after 2048 was a 24 841 8641 96. So we need to be there is rolling there. So our new mask, if that's what they're asking what mask would you use? Okay? The mask that I would use is 255 dot 255 because all that octet is on, none the third octet I have five bits on and five minutes on is what to 48 oops.

Zero. Did you see what I did? Okay, let's, let's go over again. This is my starting point right here. Okay, I just broke it into binary just to see whether I was okay. The question though, the question, I need 3000 hosts, you know, you got more than that with this mask that they're giving us.

Okay? So we start counting from right to left. So you know, you got to here was 256-512-1024 2048 and then we have 4192. Okay, so that's where we draw the line. Okay. And this would be the mass.

Now you would use this for your answer. caps. Okay, that will be the answer that would that you use. Okay. That's as simple as that. It's all it is doesn't matter.

They don't go insane. Answer the question, they'll start doing all sorts of craziness, will will have these many holes and then have these mini networks and the wall mass will be this and bla bla. No, no, no, no, no, no, no, they're not asking for none of that all they're asking you is it using this particular? These particular numbers, this IP address? What mass would you use? Okay, we'll use this mass.

All right, cool. Let's say you've answered the question. Let's go to a class B and A Class B. Okay, so once I do 2016, same thing. Oh, now we have x dot x. All right, that's where you have the default Class B there so 1-234-567-8123 45678.

So as many 400 holes, well, we know this is 256 right here, we just counted it. We're going one by 12. Well, there you go. That's really awareness. I counted by twos right to four 816 32 641 128 256 512 I have plenty, plenty but for answering the question, plenty. So what will be your new math?

The new mass will be 255 dot 2552254 dot zero. Because you're right there you're in the third octet, right in the third octet. that will be the answer. I can spell answer all right, simple answer the question. Okay. So here we go.

We got an Allen says you have a classy Oh, cool. All right. So x x x 12345678. Okay, but in 30 holes, okay to four 816 32 For certification or answering some professors question, this would be what you would use in a real scenario. If you have 30 host don't use this math. Obviously, you would use like the default Class II or something, because you always want to leave room to grow.

Okay? But in a test, you answer exactly what they want. So 30 holes, well, there you go. Yeah. 30 hosts Exactly. 248 1632 minus two is 30 exactly what they need.

Okay. What is my new mask? 255255255 dot two to four. That's that table. That's that table that I told you. We need to remember.

Okay, you need to know this is why it comes in handy. All right, this might come in handy. But again, once you have this line, what's your income in right here? 32 That's the big value was your increment right here, too. So we increment by two. Okay?

So we can grow by two all the way down. So we get to 254. Because guess what these numbers right here. This is the last network. This is the last network. So you will need to increment by whatever it is like in this case, here.

What would it be? Well, this is 120 864 3216 and an eight. So you increment by eight to get to 248. Okay, this is where multiplying comes in handy, right? That's all there is. You see the magical line gives you everything.

That's what they're calling it now. All right, that's what it gives you everything. All right. This will tell you how many networks you have available. This will tell you how many hosts you have available. Okay, and it gives you a whole bunch of other stuff too.

But again, well, you'll see it when we get there. But you see different classes of addresses. Just make sure that you are working in the octet. You need to be in. And don't forget, you have other artists meaning if you're in the second octet, your third and fourth, I mean the third octet, you have a fourth, if you're in the first octet, and that's just being a jerk, giving you a question like that, you have to do second, third and fourth octet. Okay.

But again, straightforward questions like this, you won't see I'll probably give example, towards the end of the section, that of more likely what you will see, okay, now what you will see but something similar, that will disguise an actual question is really an IP question. That's what they're testing your skills on. Okay, so that's it. We saw similar errors. Again, it's in the book in my book, the IP book on Amazon. Because the other books really, they take more of a mathematical approach where you need six whiteboards, annual 20 different talks, to figure it out.

No, no, you got 10 fingers. That's two extra. All you have is a bit you can figure it out. All right, I'll see you in the next One