Class B Subnetting with a Class C Address
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- Опубликовано: 21 сен 2024
- In the tutorial I use a class B subnet mask on a class C ip address which is called a supernet.
Find the network, broadcast, first and last usable host addresses in a class B subnet
www.danscourses...
I learned more than in any of my network lessons :) Our teacher rarely writes anything on white board, he just uses slides and talks too much.
@madedd02
I probably should have used an address between 128.0.0.0 - 191.255.255.255, but what is more important in this case is the class of the subnet mask. The class of the address (1st octet #) is only important if we are sticking to classful masks, but in subnetting the mask is altered anyway. So it is "Class B Subnetting" for me, in the fact that the mask is between a 16 and a 24 bit subnet mask and it is located in the 3rd and not the 4th octet. I hope that helps...
Gr8 explanation, loud talking, which is very desirable. Simple and educating
Keep going the same direction.
Big bow
Thank you! Solving for less then /24 had me stuck, realizing that (< 24 & > 16) was =class B (
Dude, thank you for this video. I've been using Stormwind training at my job and your video plus there training has FINALLY made me understand subnetting. Words can't express how much this video has helped me. Thank you!!!!
All I can say is that you are a gifted teacher who speaks the student language!.
I've watched several videos on sub-netting, but this is the most simplified and most explanatory. I haven't slept because i have a task to submit on Monday. Thank You for this short and beautiful video. And Joey! , thanks for asking this question.
@LittlePokeDigi to add an additional 10 subnets you will need to borrow 4 more bits from the subnet mask changing it from a /16 to a /20. that is, if you started with a /16 address. by changing the subnet mask to /20 you create an additional 16 subnets. example 172.16.0.0/16 ...to... 172.16.0.0/20, 172.16.16.0/20, 172.16.32.0/20, 172.16.48.0/20, 172.16.64.0/20, 172.16.80.0/20, 172.16.96.0/20, 172.16.112.0/20, ... and so on
That's knowledge ,pure knowledge which will become money one day .thank u Dan u rock
sir. you're mixing up the ip ranges between Class C {192-223} and class B {128 - 191}
is never matter what class is. its all about the subnet mask.
@@PineNutButter Yes
@@PineNutButter but we can not say /16 for class C it is for class B network for class C/24 so we can't say we borrow 6 bits from 3rd octet while we decrease 2 bits from 3rd octet.
That's the best netmask explanation I ever heard, thank you Dan!
The best channel for networking.. he made it very easy to learn networking.
@alebert32 I stand by what I said, if you are borrowing bits it is not classful, classful means the subnet mask is /8 /16 or /24 only. I titled the video as Class B Subnetting because I start with a /16 netmask and then I proceed to subnet it. Regardless of the number in the first octet the subnet mask is what is important in subnetting.
YOU HAD ONE JOB JOEY
lmao!
lol bro
Very good explaining? ❤ Love it. I wish everyone taught like this. An egoist tries to make himself look smart by confusing people, but a truly SMART person makes complex things very easy to understand.
@madedd02 You are right having the number 192 in the first octet would signal a class C address. However one thing that is not always covered when talking about address classes is that they need the netmask to actually cover the correct range of numbers in that class. So when I talk about class B I am referring to a starting netmask of 255.255.0.0 as opposed to starting with a netmask of 255.255.255.0
danscourses how to subnet 192.168.10.0/22 to get 5 subnet with host 190
@sbrave if the magic number is 4 (in the 3rd octet) meaning the subnet mask is 255.255.252.0 the the networks are 192.162.0.0 and 192.16.4.0 and 192.162.8.0 and so on so the last host in the 192.162.0.0 subnet is 192.162.3.255 and the last usable is 192.162.3.254 because 3.255 is the broadcast address or the last host of the subnet before it becomes a new subnet at 4.0 . In other words the octets turn over after 255 because an octet is 8 bits which is 0-255 or 256 total values starting at 0
I was kinda confused about subnetting class b networks. Looked about a bunch of other videos this morning. No luck. This video nailed it for me in five minutes. Thanks.
what ipv 4 means
Internet Protocol Version 4 👍
Never came across the magic number before. It's a good way of explaining it. Cheers
I came across your channel by accident but you explained in 5 mins what my teacher couldn’t show us in an 4hr course
This is the type of question's my professor is throwing at us like, what's the zero network? , how many bits borrowed? What's the formula for host, for network? last host, first host? Thank you this video makes things clear.
@LittlePokeDigi The magic number is the same in every octet or Class. /16 the magic number is 1, /17 magic number is 128, /18 magic number is 64, /19 magic number is 32, /20 magic number is 16, /21 magic number is 8, /22 magic number is 4, /23 magic number is 2, /24 magic number is back to 1,
That is money sir. Helped me a lot.
@alebert32 I am sorry, I meant Class C. Any number between 192.0.0.0 to 223.255.255.255 would indicate a class C address, but what really matters today is the length of the subnet mask. That was my point
Man god bless you i've been trying to do my homework and just couldn't get one right this video just saved me..
@abonao I think I should have used an address in the actual Classful B range for the video then it would avoid confusion. However in the video the important thing is the length of the subnet mask. If its length is /16 to /23 then it is subnetting in the Class B range.
i am studyin ccna and am trying to understand the subneting. i found it hard but i think watching through your video it gave me a hint of how to workout subneting. thank you and if you add more videos about subneting it wil help me more.
@MrTr4nc3 remember that the Subnet Mask is 11111111.11111111.11111110.00000000, so the subnet is happening in the 3rd octet (left to right) and the MagNum is 2. so the networks from the first subnet are: 192.196.0.0, 192.196.2.0,192.196.4.0, 192.196.6.0, 192.196.8.0, and so on until 192.196.176.0, 192.196.178.0. So ask yourself in this scenario what kind of address is 192.196.176.255 or 192.196.177.0 if it is between .176 and .178 then it is a valid host address how else can u get 512 hosts
your videos have been helping me through my apprenticeship in a great way, just wanted to say thank you, as i'm now reviewing some of those vids for my mid-term exam!
having my cisco ccna 2 4.0 practical test tomorrow and this helped me alot, thank you so much!
@madedd02 look at the cidr. 192.162.3.6 is a class c range, but the /cidr shows /22 is the class b range subnetmask. therefore the octet you need to look is at the 3rd octet from the left. and screw the class c subnetmask. Yeah I know you'll be confuse. Unless you want to do the boolean andding or the formulae which is complicated, this one is pretty straight forward.
COME ON JOEY! WHATS THE MAGIC NUMBER!!!!!!!!!!!!!?????????????
+Ferret2YourFace Here is a little summary :)
class "A" /8, "B" /16 and "C" /24 (Normally)
Now, /22 means we've borrowed 6 bits from Host portion to the Network or Sub-net ID portion in class "B".
Now, count from left to the right side of the bits in the following series of (Digits!!)...
128 64 32 16 8 (4) 2 1
WHAT IS THE 6TH BIT FROM LEFT TO RIGHT???
OF COURSE IT IS "NUMBER 4" :)
If we borrow 7 bits, the magic number will be "2".
It is the lowest Network bit we can CREATE ranges with.
(Hope it will help you a little :)
+shahab384 LOL he's trollin' dude ! xD
THE NUMBERS JOEY! WHAT DO THEY MEAN?!
Abusive to Joey much?
KJASHDKJASH
This is one lecture that I will never ever forget for it made my SUPER and SUB-netting grasp easy and understandable now. I am using Boson Calculator as a tool for verification and it always made me smile :-)! VERY VERY COOL!
dude, thats money alright...! might be able to pass the remaining CCNA chapter yet!! So easy to follow, thank you..
Regardless, if the ip address is 192.162.3.6 /22, the network is 192.162.0.0 /22 and the broadcast address is 192.162.3.255 /22 just like I showed in the video.
/22 subnetting is really useful with 4 sizes jump in the allowed sizes. Thank you.
@MrTr4nc3 In a /23 address 11111111.11111111.11111110.00000000 the last borrowed bit is in the 2's place so the magic number is 2 meaning the networks go up by 2. So the networks are:
192.196.176.0 - 192.196.177.255,
192.196.178.0 - 192.196.179.255,
192.196.180.0 - 192.196.181.255
Watch my video tutorials on subnetting with "the Magic Number" you will find them in my CCNA1 playlist
My question is (2)...Why is there a mask and is the mask the same definition as a disguise?
The title says subnetting a class c ip address as a class b because de CIDR is in the third octet. /22 (You can treat any ip address as any class if you are giving an example.) Lets say I have a couple of networks in my private company, I can still use this class C ip address and give it a class B netmask.
great stuff that helped me out a lot with the supernetting as you mentioned in your description
Hello! I am currently reviewing for CCna RS training. Planning to take CCNa Exam around october or november? hopefully.
I was searching on youtube. Found out your channel.
Current lesson we had is about VLan and subnetting.
I'm gonna study your videos as a guide as well as review what we had discuss in workshop.
Thank you for this. :)
Now it makes sense. Tomorrow I'll come back to watch the same video and be confused all over again...lol
Thanks for such a clear explanation!!!!!!
@danscourses Hi there, I watched the 3 videos and I understood the meaning of the Magic Number, it is a good point to use to understand the networks.Now I think I can do it all right! Thank you very much and congratulations on your good videos.
Why is it the last usable host if it keeps going up by 4. Surely as networks go up so do usable hosts?
@notomab3 Yeah the fact that he is using a class C IP to show a class B subnetting is REALLY FING CONFUSING!! I'm glad you have confirmed my suspicion that he was doing it wrong.
and all CIDR indicates is how many bits you are borrowing, either for a classful or classless
thanks for your time, and good luck
The 1st octet begins with 192, so it is a class C network but you assumed like class B network and why?
Because I used a class B subnet mask, then it is kind of like class B subnetting but with a class C number space (192). It really doesn't matter to speak of "classes" when you can do whatever you want with the subnet mask. That is the main point. how do you subnet when you start with /16 versus /24
@danscourses what happens if you are supernetting a class C and you get a /22?
i just think for the sake of the title and the use of a class c address was a bad decision. i was only trying to brush up on my studies.
Cheers mate, helped a lot, thats a quick and effecient way to subnet
thank you very much sir,..with
your patient and clear explanations,...very big help..
I appreciate this video so much. Thank you!
why are you working in the 3rd octet, when it's a class C address? I don't get it
+Erikson Tuazama
YEAH!!!!!!
exactly! you took the word right from my mouth. That is a class c address not a class b. class b ranges from 128 to 191.
+Tito Cotto Man ... You know that this is a CLASSLESS Ip adrress right ? it depends on the subnet mask to determine which Class it looks like , don't depend on ranges because it is Classless address looks like Class B but with additional 6 bits with it's subnet-mask...
+Tito Cotto Man ... You know that this is a CLASSLESS Ip adrress right ? it depends on the subnet mask to determine which Class it looks like , don't depend on ranges because it is Classless address looks like Class B but with additional 6 bits with it's subnet-mask...
This is classless and he also said he is using a class b subnet on c class address
be aware that in subnetting the 0 and the 255 is used differently in cisco etc
Good lectures in this channel. Could you please give the number of subnets and number of hosts per subnets for this particular example.
@danscourses
It's a CLASSLESS IP
but under class B
I have a question, what happen if the IP range are in the class b range, but the /CIDR shows in class C or A ? how do you make a calculation using the same method like the one you're teaching ?. I give an example, let say 155.162.3.6 / 25 or 155.162.3.6 / 7. How to applied your calculation ? please respond to my comment. Thank You.
How is it that you say you are going to subnet a class B address of 192.162.3.6, just because you decide to put a /22 in front of it, if the class of an address is defined by the first octet? If the first octet is a class C address. How does it magically convert into a class B just by altering the mask?
Isn't a class C address 192.168 instead of 192.162 as shown in the vid?
Thanx alot dan. You are so easy to follow
@alebert32 I agree, I am going to have to redo this video.... just dont want to, too lazy :)
great way to explain it!!
is this right ?
Broadcast Address: 191.240.93.255
Usable Host Range: 191.240.92.1 - 191.240.92.28
yes i got a question , the ip address you have used as in example ,is it a class b or c?
That's a lot of addresses. It should be called VLSM with a formerly known as a Class C address space subnetting. Very few companies will ever use this type of scheme. Since they can use all of the addresses they want withing their hidden private LAN.
@danscourses I have a similar problem with an address of 172.16.10.0 /23. but i don't understand how if the magic number is 2, do i just keep counting with 2's all the way up to 256? i'm not really explaining myself well. but in regards to the previous persons question, how did you get 192.196.176.0 to 192.196.177.255? how did you count that out? sorry if the question is kind of stupid, i just for some reason can't wrap my brain around it. Thanks!
@abonao Yes, I agree.
@danscourses I don't get it. Are you saying for each range address goes from ex:
192.162.4.0, to x.x.4.1, 4.2, 4.3 etc up to 254 and then rolls over to 192.162.8.0?
I'm still pretty new at this and everybody explains it differently...lol
To assist with determining the number of hosts, I have always kept it straight by adding the the zero bit binary place values together starting with the 7th bit in the last octet till you reach the first borrowed bit, i.e. - 2 + 4 + 8 + 16 + 32 + 64 + 128 + 256 + 512 = 1022.
Do you recommend doing it this way or do you have another method?
do you know where can i find how to convert a class C ip address into a subnet mask that can provide 32 subnets
I wish you would explain the magic #, your saying 4 but the last one is in the third position, CONFUSING help
Great explanation. Thanks Dan!!!
"THATS MONEY!" yes sir, yes sir it is :)
just one question, why you use 255 in broadcast and 254 as last usable?
That's good Dan although you forgot to mention 256-4=252 for the magic number or block.
novadhd The block is 4, (11111111.11111111.11111100.00000000)
2^6=64 Subnet and 2^10=1024-2 =1022 Host, to find the Magic Number you already know that /22 = 255.255.252.0 all you have to do is 256-252=Magic Number,
lets said 172.10.5.0/18 =255.255.192.0 now to find the MN all you have to do is 256-192=64(Magic Number) 0.0, 64.0, 128.0, and so on
11111111.11111111.11000000.00000000
Bits on=Subnet, Bits off-2=Host. 2^2=Subnet and 2^14-2=Host
Learn you power of 2 and you will be fine (:
I'm guessing this example should work the same for all like scenario's? So I should be able to use this method with the following examples
101.11.1.0 /15
172.11.1.0 /27
192.11.1.0 /22
would it work for things such as 172.11.1.0 /12?
very good video. Please keep it up! extremely helpful.
Thanks for help, very useful information !!!!
good video..learnt the mechanism..thanks
I want to explain the way im learning this but it would take like 6 or so messages just to explain it.
I am Network student .
i still dont understand i am busy with subnetting from last 3 weeks but every time i trying to do i get confuse and stuk in middel and then i forget everything any tips or practies.
help me sir
Class C has total of 254 host... Ip networks has three parts: Network id, host id, and broadcast id.
Easy to understand, thanks.
Hi there, Great video explaining the prefix thing. I cannot understand the following : If I have an address of 192.196.177.160/23, a network address of 192.196.176.0,why is the last usable address xxx.xxx.177.254 and not 176.254? It sounds stupid as I had the host address already using 177, but could you explain me why? Thanks again for your cool video.
HOW AM I SUPPOSED TO DETERMINE THE NETWORK, BROADCAST AND HOST ADDRESS IF I ONLY HAVE A RANDOM IP ADDRESS WITH NO /CIDR??
You use the first octet to determine if it is a Class A, B, or C address. In this example the first octet is a class C. Im not sure if he says that in the video. But if the IP address is classless you only worry about the mask. Look it up in Google to find the 5 classes of IP but you will only use 3 classes usually.
Welp too late now. I already failed my exam. ¯\_(ツ)_/¯
well...at least you know what to expect the next time.
that was confusing. I don't understand how you were able solve the broadcast address.
i got to calculate is net add= 191.240.93.0
1st host=191.240.93.1
last=191.240.255.254
broadcast=191.240.94.255
yes exactly.
Close to perfect explanation but you missed some critical information which will leave some people lost.
Well explained sir.
great explanation
yes
Can any explain me this: How many subnets and hosts per subnet can you get from the network 172.25.0.0 255.255.252.0?
Answer: 64 subnets and 1022 hosts?
I got the magic number which is 4
so the first usable network is 172.25.0.1
last usable network 172.25.3.254
172.25.4.0 so on....
in the first usable network i can have 253 connections?
so total i got 1012 connections in each subnet
and i figure 256 divide by 4 = 32 subnets
im getting wrong answer for my network connection in per subnet!
how do you get the magic number without knowing the CIDER /22 ??
You can't, unless you have the subnet mask in either binary or decimal.
ok HERE IS MY DELIMA. my teacher gives us the number of hosts.... and tells us to find each network for those hosts in those videos. im in college taking a cisco 1 class. but im not getting class b or a part of it like this one " subnet for : 177.177.0.0 with 16382 hosts, 2046 hosts, 254 hosts, 14 hosts and 2 hosts ( 2 hosts is always 30 i know b/c by then it has dropped back down into class C) but it confuses me and me being a woman i am looked down upon. im the ONLY girl in my class. HELP ME
Thank you teacher!!!! Lots of love from Malaysia 😍💕
191.240.92.0 /23 is your network address, now you tell me your broadcast. :)
checked my own subnetting calculator and it was right... just thought I'd mention that because this reply confused and annoyed me lol
JOEY WHAT IS THE MAGIC NUMBER?!
how would you do this if it was /16 or /24?