How do we Calculate VLSM?

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Alrighty, welcome back. So how do we calculate vlsm? Yeah, the three rules, remember, highest laws, uses your network should be should be in contiguous right. Always keep these two in mind. But let's go to a lab. And it's going to done and you'll see the order that we do it in.

Okay? And always remember to check your math and you're doing the line right and all that because you it's easier to get along. Okay, CSI. Alright, we'll go on to the vlsm How to lab. Alright, so we saw more or less the concepts of what to do. So here, I already went ahead and put in the networks that we're going to or the number of nodes that we're going to need.

So we see we start from highest to lowest right from 350 300 201 5050 and 45. And then we have the 172 16 00. So we're going to pretty much the same example that we saw previously. Okay. And then we have our bid values up here so we can know you know where the line is and stuff like that. All right.

So the rule states that you must use the zero network first. So right off the bat, you know that this is gonna be 172 dot o Ctrl, z, okay? Block 172 72 dot 16 dot zero dot zero. All right, that's going to be your network ID right from the start. That's going to be your starting point. All right, so we know that we need to count for 350.

Why, you know, we come from right to left, start by two and double as you go. So go up to here, that's 256. And then we come over here that's 512. For our first lunch. is going to be right there. Right there.

So we know that Okay, one bit in the first line is right there on the third octet. So to calculate for broadcast, there you go. Okay, one and then this is all to verify. Okay, so let's take out, let's put in the broadcast address, we got 172 again. Now let me just turn this log on, because this is gonna make life a whole lot easier. Right 172 dot 16 dot, third octet, zero, plus this one is one, and then dot.

What's the fourth octet? Well just add all the bit values means you're adding all these guys right here. So that's 255 to 500. So what's our host range While we have x dot x dot what's after 000? dot one? What's before?

Okay, we'll have in there. No, no, my God, there we go. What's before one dot 255? One dot 254. There's one not one women, one, not one. Then we have the line.

And then we have x dot zero dot one dot 234. Okay, let's put this guy back over here. All right, so we have the range. Here's our zero network. Here's our network ID. Here's our broadcast one dot 255.

And then what's in between? So what's our new cider, cider, classless inter domain routing, that's what it stands for. Right? variable length subnet masking classless routing All that stuff means the same stuff. So we have a slider. And where is it?

There it is. Okay, we have 16 Plus we have seven more bits. That's a 23 was 23. So that's our new cider. So okay, so what will be our new network ID while we look at one dot 255, then the next one must be 172 dot 16 dot two dot zero. That's our next starting point, because 255 flip for the one or two, reset itself to zero.

And if you look at our network increment, it is two. Okay, it is two. All right, cool. So we're done with the first one. We're good to go. Now we need 300 nodes.

Well, guess what? We don't have to move the line. We need to keep it there. We have no choice because we put it here then we only have 256. We have to keep the line there. All right.

So we do the same procedure. All right. Add that one to that. 255 to the to the zero. So we've got 172 dot 16. Two plus one is three, zero plus 55 is 25.

Wow, that's some pretty hard math there. Okay, we got x dot x, mean it up, okay? And then we have to not one, right, that's zero. And then we have a little line here. And then we have x dot x dot three dot 24. That's before that one, right?

So we're good. There's bring this back is what hit him. I don't find though. Okay, and we still are using the same cider 23. Okay. So that's all we got went.

That's the last available IP that we use. So what's after that one, two dot zero. We need 300 hosts, we can move the line so we keep it the same. We add that That one to the two gives us the three, we add the 255, right? adding all of the values together to the fourth one, that gives it to the five then you find out what goes in between what's after two zero what's before, three that 255. And we do the same.

All right, so what's our next starting point? For dot zero, right, as we maxed out there, so we got 172 dot 16 dot four dot zero. Awesome. How many nodes? 200. Okay, well, we now are like gonna be right here.

That's 256. Hang on the last 248 1632 64 128 mB 256. Right. So, things you probably know, Jesus. Okay. All right, so we got there.

So this is our new line right here. So now we're in the fourth octet. Now we're in the fourth octet, so forget about this here. Okay, forget about that there. Oh, this is getting annoying. Okay, here we go.

Alright, so now we're going to go ahead and find the broadcast. Well know the first three octets are now not going to change 172 dot 16 dot four dot one Whoa, you know all the big valleys are right? To 55. Okay, what's in between x dot x dot four dot one through x dot e get away. Okay, line, okay. x dot x dot four dot 254.

Okay, that's before that. Let's bring this back over here. Okay. And then we're going to go ahead and put our new cider, which is one bit one bit over. So that's a 20 far. We're in the fourth octet, four octet.

Well, either way, we maxed out. So what's the next available IP address? 172 dot 16 dot. Come on. Five dot zero. Very good.

Okay. 500 nobody 150 Well, I do 248 1632 64 128 still not enough. So align needs to stay right words out. Okay. No big deal. So we're going to do once again 72 dot 16 dot four dot Activity five again, Mike goes we're adding those last eight bits.

And then what's in between x dot x dot five dot one through x dot x dot five dot 254. Okay, that doesn't want to play to fly for sleep with us back here more or less with each other. Okay? And we have the same thing, ciders a mask, okay. All right, I'm going to 50 now now we're gonna have 50 but we will need a starting point. Whoops.

Before, sorry, five. So what's our starting point this maxed out right. So 606 dot zero. So 172 dot 16 dot 16 dot zero. There you go. When he 50 though.

Okay, so this line is not gonna be any good anymore. So we're gonna go to four 816 3264. There we go. There's our new line right there. Awesome. The means that we have two bits in, right?

We're over here. Okay? two bits in either 128 and 64. So there will be 63. Okay, this will be 63. Let me say something real quick here.

For this ones are 23. Yes, the broadcast is okay. I'm good. All right. So this would be 63. Again, focus on the fourth octet.

So 172 dot 16 dot six dot 6363. That's our broadcast. What's in between x dot x dot six dot one through x dot x dot six dot 62. Okay. Let me line this up better. I mean bring this over here.

Okay, and now we then move the line two bits over. So this is now a 26. Okay, and then the last one here, right? What's the next available now within reach our max didn't reach our max. But what's the next available six dot 64 right and if you see if you look at it 64 is our increment on the fourth octet. So 64 is your 64 so we're good 172 dot 16 dot six dot 64.

All right. So we didn't move on, we have to keep it there. All right, and then again 63. So this will be 127 172 dot 16 dot six dot 127. And then what will be the range x dot x dot six dot 65. That's after 64 and x dot x dot six dot 126.

That's before 127. All right, that's it. And then go too far there, and then the mass remains the same. Or you can see it varies slightly 2324 to 26. Right? But again, it all depends on the needs of your network, the point of all this and you're not gonna have to do this This is I'm doing it so you can understand the concepts of vlsm and how you would do it.

Basically they just gonna say okay, if you have a cider 30 or things like that, and you have a cider 23 you know what's up and then we're going to go to seven now we're what is vlsm things of that nature. But now you know how this works. You start with a zero network, you find how many hosts you need, like in the first example is 250. You draw put the line where it was, which was a 23 mask, you find your broadcast and you look for your range, next available IP two dot zero and do the same process over and over and over again. And again, this is to not to waste IP addresses public IP addresses public you can do this in a private network if you want to as well. I doubtful that's going to happen but you could do that you can do it in a private network as well.

But this was really meant just like Nat Okay, now it was also meant for the you know, to slow down the demand. Or the death of ipv4. So was vlsm so was vlsm. Okay? But you need to follow those rules, you need to follow those rules, especially these main two which are started the zero network and start from the highest and then go to the lowest. That's it.

And you start with whatever they give you, whatever they give you. Okay. Not sure whatever starting point they give you, that's where you start townie or whatever the case may be, right. But they can give you a classy and then you're always working as a 24. And they want you to do a vlsm one in there. So then you only work in the fourth octet.

So this can change I just use a bigger example using a Class B network. But this is not a concept before I saw that we did one. This is all it is to vlsm. No big deal. See in the next

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