CIDR and Subnetting

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Time
1 hour 19 minutes
Difficulty
Beginner
CEU/CPE
2
Video Transcription
00:02
Well, welcome back to cyber areas. Create a sudden it today we're gonna go over cider and submitting. I'm your instructor. Trendy arrow gladdened begin.
00:12
So you said we're gonna win with cider is And also we're gonna take a look at how to do some basic subject.
00:19
Cider is your classless inter domain routing. So what? This helps ISS
00:24
when you're somewhat classless Networking, right. Imagine the class full networking means you have your network said your B networks. You see networks meaning if you use a network, you have, you know, two million up you dresses for
00:37
that no network, which is, you know, you're probably not waste quite a bit of those I p addresses where, as you know, class see, you only have the ability to put in 254 eyed peas into a network.
00:49
So the way this is represented here was with a slash number notation. That number corresponds to the number of network bits and sudden it bits BB and used for that network. Right for that, Suddenly
01:02
so, slash 24 is a traditional, classy network being it's using 24 bits for the networking portion. There's eight bits for the host portion.
01:11
Right? So that would equate to a sudden that mask up to 55 to 35 to 35 in a Class B network. Thank you. Need you know, 16 bits, So slash 16. Class A is a slash acres. You need eight bids.
01:26
Uh, and the way that these were gonna work. You know, if you add up all eight bits in that octet, you're gonna get to 35 right?
01:34
You got a mirror that this is not supported in rip routing protocols. Right? So rip is a class full networking routing protocol,
01:42
so let's go ahead and move on to a little bit of cider practice. I will give a few seconds deposit and get some No paper and a pen. We'll go ahead and begin.
01:53
All right? Hopefully you guys got this done already. That's good. Go ahead and begin Otherwise. So here. We're gonna go ahead and just do 2 35 So what we need to dio is we need to add up our different bits. Right?
02:08
So we're gonna imagine this first bit here, so I got 1 28 plus 64 is 1 92
02:16
3rd 1 that's gonna be 2 24
02:21
Because this is your 32 place, remember?
02:23
When the next one gets it to 40 for a 16? Well, at 84 to 1,
02:30
which will.
02:31
So let's go ahead and do to 48.
02:36
2 52
02:38
onto what? That's a 5 to 54 then two. Well, 2 55
02:46
Okay,
02:49
2 55 total. Right.
02:51
So what we need, how many bits are we being used here? So this would be a slash eight
02:57
going screen, and we'll move on to the last one, so we know we need so
03:02
we need eight here.
03:06
Eight bits are being used here and eight bits. Are you being used here? So if we go ahead and just begin this with 1 28 we know that only one bit is being here. It used here. So this is gonna be a slash 25
03:19
right?
03:21
Because I always 000000
03:25
Right? Yeah.
03:27
So, essentially, this portion here would be your host.
03:30
Who's bits,
03:32
and this is the last octet. You have your sudden that bit.
03:38
So the last one, I hope you figured it out. We need 30 different bits.
03:43
So I'm gonna go ahead and move, Isn't it decimal? So I know that there's gonna be 2 55 to 55
03:51
too fortified to get us to the nearest classical network.
03:54
So I'm gonna go ahead and do my little thing that you hear networking bits sudden at best host bets.
04:02
So we know that we have 24
04:05
which would leave us with six sub nets and to host, right, because these two together would give you your slash 30.
04:15
So let's go ahead and put these 67 that bits into a for six on your to host bits. Right?
04:23
So essentially, we could just minus three awful of 2 35 because this would be three if you did a one of the one.
04:30
So 40 to 55 minus three would leave us with 2 52
04:36
So that is the last octet of that, son. That mask.
04:42
All right, clear screen. And we will move on here. So subheading, the way that is generally kind of scene is you need thio. It's a determinant based on the host eyepiece that you need, right? So if you have a network that only has 64 devices.
04:59
Then
05:00
you know you base your somewhat off that you don't need a full class C sub net if you need 64 I p addresses, right.
05:06
You actually need a slash 25. Because remember that 64 is being used, but then you need you have to minus two for the usable. See, actually end up with 62 usable I p addresses.
05:18
So the quick way I like to determine my son. That mask. Uh well, use this again. So do the slash 28 up here
05:28
I do my networking, my sudden obits and my host bits. So this would be
05:33
24. This would leave us with four sub nets and four Host that 1234 So 1 28 1 92
05:44
to 24 to 40. Right.
05:47
So here we're going. You know, we got our quick, sudden that mask So to 35 to 55 to 55 to 40.
06:00
And here's how the way that I utilize this last suddenly or this last said not here is so if we did 2 55 minus 2 40
06:10
2 56 apologize. That leaves us with 16 right? We know that our block size that we can utilize for I P addresses is 16. We can hold 69 piece per sub net.
06:21
Right.
06:24
So let's go ahead and move into a slash 22. Here, clear the screen off.
06:28
So slash 22. It gets a little bit different when you get into the class. Be submitting.
06:34
So network suddenly host.
06:39
So we're gonna do first class full 16. 16. It leaves us with this and 10 host bits. Right.
06:46
So we know that. 123456
06:50
No,
06:54
or 5678 Right. These are the last to our tests.
06:58
So let's go ahead and do the last bit. Maybe we could just minus three. So we know that this is a duck to 52. If you do the math of adding up, these or you could just minus three from that there.
07:13
So, you know, whatever, that stupid too.
07:15
So we can kind of do that same trick with a Class B networks to fortify or 2 56 minus 2 52
07:24
Right. That leaves us with
07:26
four. Okay,
07:29
So how that's gonna work is you can actually look at essentially think of it as we have four class C networks that we can utilize, right?
07:36
So I'm just simple 10 1
07:40
you know, 00
07:43
through 10
07:45
1.3 to 55. That's our actual eyepiece base that we can utilize for that slash 22. Right?
07:56
Because if you think about it, we're essentially using three
08:00
different, because then you have your 12 and your three networks, right?
08:05
They're using four different classy network. So you can still kind of use that trick. And it would be the same thing if you were to suddenly a class A network. You could you could essentially say you had this many class B submits to utilize.
08:20
Um,
08:20
so you have, you know, 10. 24
08:24
i p addresses. Because if you do to 55 by four class sees no,
08:31
10 24
08:33
the other way that you can do that here If you need to determine if you have Ah, this is one way. Actually utilize a calculator. Um,
08:41
if you look at this year, you have 10 sudden at best, Anyone who determined real quickly how many
08:46
I please you. Have you can do 10 or to raise 2 10 Remember, because you can use those basic. There's a base to system. And that would give you 10. 24 as well. Right?
09:00
I guess this would be to 56.
09:03
Let's go ahead and clear the screen off here. Let's go down to this bottom portion. Determined subject mass needed for the I. P is needed.
09:11
So one thing we can do here
09:13
due to 56
09:16
minus 66
09:18
All right, so that is gonna give us 1 90 right? So when you look at what we can utilize off, that's great. You essentially saying that your sudden that mask
09:28
needs to be
09:31
essentially below this number, Right?
09:33
So if we do the 1st 1 of 1 28
09:37
that's below. We can utilize that we can use one sudden. It bit
09:41
s o. The next one will be 64 which would equate to 1 92 So that would be about right? We can't utilize that. So then you're so that would be
09:52
this far.
09:54
So essentially saying that the last act Tet are saying to 55 to 45 to 55 that 1 28 or a slash 25. Right, Because you're using that one extra sudden up it.
10:09
So again, that would look like Network 24 Sub net one host seven.
10:18
All right. Hey, let's move on to 2112.
10:22
So let's take a look here. Here's where we're really going to want to utilize some actual calculator math unless you're really good at this stuff.
10:31
So let's look at what we're gonna utilize here,
10:37
because obviously we can't do our 10 24 trick. Here are the 256 minus the peace space, because we're gonna have to actually tap into the Class B network.
10:48
So let's try and figure this out here. The way I like to do it is kind of the lazy way is we know that
10:56
10 suddenly bits could just learn is 10 24.
11:00
So if we give it one extra so 11 would be
11:03
2048. Okay, we don't have enough still so 12
11:09
give us 40 96 minus two. Of course.
11:13
So we need to use 12
11:15
for the host.
11:18
I wish it if we d'oh in order here,
11:24
do 16. Because we're gonna use a Class B network for that.
11:28
Which means we had to borrow four bids for this. Which means we use four bits for the sudden mask.
11:35
So let's go ahead and do 2 55 to 55 because we know that is a Class B network right here.
11:43
And then we need to figure out for sudden it's a 1234
11:46
1234 There we go. So 1 28
11:50
and I'm just gonna go ahead and add these up. 64 32 16. So
11:56
1 92
12:00
to 24 watts, bed to 24 add that last 16 in there.
12:07
What gives the 2 40 So here would be our protector. Zero.
12:11
And this would be remember, So add these two up, so this would be a slash 20 network.
12:24
All right, so we're gonna go ahead and move on to the quiz here. Hopefully you remember. What is the subject mask you need for a network that requires 254 I p addresses?
12:35
Give you second deposit
12:39
already? Hopefully everyone got
12:41
that. You are going to require just a classy network, right? You just need
12:46
slash 24 because you need eight bits for 2 54 addresses that will give you a perfect amount. Now, again, that doesn't give you any room for expansion because you're going to utilize every I p address.
12:58
But that will work, right?
13:03
All right. In today's video, we went over what cider is. And we talked about how to utilize that Byner math to determine our sub net sizes.
13:11
Don't thank you for watching today's video, and I look forward to a senior next one,
13:16
huh?
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