Just add little bit note.. Rather than memorizing 128 64 32 16 8 4 2 1 and so on so forth... just follow this link for above. Start with 128 (128+64 = 192) (192+32 = 224) (224+16=240) (240+8=248) (248+4=252) (252+2=254) (254+1=255) Overall, wonderful explanation for sub netting...
After spending a day trying to figure this out yours was the only explanation that's made any sense. Thanks man. BTW you sound like Jamie from Deus Ex.
thank u so very much this concept had been on my nerves and now watching ur video just before finals is something i can't explain....this is so perfect
This is the first video I've seen that differentiates between the public and private subsets of classes. That finally made a lot of stuff click for me! Thanks!
You can take the 128 and then add the next number under it, then keep adding... so 128 + 64 to get 192. Then add 32 to get 224, etc. So go right to left on the bottom multiplying by 2, then left to right on the top by adding the next number.
This video is an oversimplification of what is actually happening, but it is a helpful video nonetheless. Subnet-Mask ignores all the IPs below it but leaves all the high numbers(octaves) of what's left for the subnet. After you get the SubNetMask: 255.255.128.0 Just look at the last two Octaves(Numbers): 128.0 The first 2 octaves don't matter because they've already maxed out, and in the 3rd octave, anything below 128 doesn't matter to the subnet. Two of those left over IPs must be assigned to identify the subnet itself for delivering data and broadcasting data within the subnet. These are; 1) Network IP: 153.34.128.0 (That's the lowest unmasked value, it starts where the SubNetMask masked it) 2) Broadcast IP: 153.34.255.255 (Note the last two Octaves have gone max value, that's because the SubNetMask isn't stopping it) The FirstHost and LastHost are just in between those numbers.
Jordan,same deal with me. Lol : Jordan K 1 year ago this really helped me, and your explanation is so easy it made me laugh after being so confused from sitting in lectures
Thanks for this video. I'm in the process of studying for my CCNA and the subnet mask part was getting confusing for me but this video was a light bulb going on for me.
Thanks for taking the time to make the video. I have one criticism though, reading every part verbatim takes up a lot of time and removing this would make future videos more to the point.
Good Video!!! Still a little fuzzy about the the subnet mask. If it is a class A IP - will the subnet mask be in the 3rd octect? Or are the last two octects the only ones that can be manipulated?
hes expecting you to have a general concept of what your doing he explained that hes not going into depth he was just doing a video to help others but he wasn't going to go into depth so for what it was it was perfect for me, helped me pass my test with the way he explained it so its all about how much you actually know already, if you don't have an understanding in binary and networking your not going to understand anything hes talking about really, hes just helping people who already understand it but are still having trouble with it so hes offering a different solution and i like this solution it helped me a lot.
I agree. Actually, his explanation is somewhat clearer for me than other more detailed, drawn out longer videos. Straight-forward and no fluff works well for me.
CIDR gives you the number of bits that are 1's starting from the left. Finding the subnet mask from a CIDR is as simple as putting each 8 bit binary string into decimal.
Great video! The only thing I'm not getting is... Why did you subtract by 2 to get the last IP in the first example, but subtracted by 1 for the second one?
There is one thing I have a tiny problem with understanding. 11:35 here you talk about subtracting 2 from 136, why 2? Do we always subtract 2 from the final? Is it because 135 is the broadcast IP and thus we always subtract 2 to get the last available one?
Hi! I was wondering what happens if the subnet number is either 8, 16, 24, or 32. Would you subtract it from its own number or does it have to be subtracted from a number that is larger than it?
In example 2 there is no mention of the 4th octet, 242, and instead you work with the 3rd octet, 173. Is this to do with the subnet working out in the 3rd octet? As opposed to the first example where everything was done in the 4th octet.
Great Job man. I just have 2 questions. The top row in green? Are those the IP class ranges? And how do the bottom numbers correspond to the top one in green? Other than that, I got everything down.
I'm not sure if this was explained in the video but I just discovered that you don't have to memorize the chart. Just take 2 and keep doubling it to 128 for the top part of the chart you just take 256 and subtracted the bottom number's thus giving you the top numbers.
Why to memorize ... 255-1=254 but host number start with zero so again add one = 255 Similarly ( 255-2)=253 then 253+1 = 254 (255-8)= 247 then 247+1 = 248 (255-16)=239 then 239+1 =250 Not even need to remember 1 2 4 8 they are in power of 2 2^0 2^1 2^2 And so on And most important we don't get excel sheet Still nice job thank you
it was easy explanation but i got little confused when you start to do the firs host on the next example. i have to watch over and over hopfully i'll get it . much much better than my stupid cisco teacher
+jetawe gameTV Go watch the Asher Dallas Lecture Subnetting series .. I have watched it over the course of a few days and it has helped me get a really good understanding on how to subnet. it says there are 6 parts but there is only 3 parts available.
Maybe it wasnt totally clear, but he kinda explained in the beginning. IS that 2 of the addresses are reserved. One for network address and one for the broadcast address, These are the 2 that you subtract. So lets say you have a network with 64 hosts, but there are only 62 usable host because the network and broadcast address are reserved.
There are some "truths" you learn along the way when learning this stuff. A few of them are: - The NetID + 1 = The 1st Usable Host IP - The NetID + the Increment = The *Next NetID* - The *Next NetID* - 1 = The (previous NetID's) Broadcast IP - The *Next NetID* - 2 = The (previous NetID's) Last Usable Host IP
first example has 32 subnets with 8 host per subnet. He needed to list the ranges 0-7, 8-15, 16-23 for this to make sense. The second example is a class B (first 16 bit network, last 16 are host) cidr 17 on class B means ( 16 net, 1 subnet, and 15 host bits) 2^1 = 2 subnets and 2^15= 32768 host/subnet. the 2 (third octet) subnets are 0-127 and 128-255 (NOT 256). A 173 in the third octet fall into the second subnet (128-255). his network id and brocast IPs for this example were correct but his grouping on the right was not depicted well and should not have went to 256. Also he needed to explain the number of host for this example for the numbering (especially in the forth octet) to make sense.
I appreciate your creativity , I followed your way but it fails somewhere because it doesn't have specific formula. for instance Ip 184.136.0.0 /16 , 32-16 or 24-16 which is correct ? i am confused
Rahter tham memorizing all those numbers (128 192 224 ...) just keep in mind that you fill the first 29 bits with 1 and the rest of them you set them on 0. Tadah.
Just add little bit note..
Rather than memorizing 128 64 32 16 8 4 2 1 and so on so forth... just follow this link for above.
Start with 128 (128+64 = 192) (192+32 = 224) (224+16=240) (240+8=248) (248+4=252) (252+2=254) (254+1=255)
Overall, wonderful explanation for sub netting...
+Nijer Manus exellent tip
I have a question Khan. Why it in 128, not in 136 network. I am referring to 11:11. Thanks.
thank you
not all heroes wear capes
yes this is good also.
After watching many videos, I finally found this one that makes sense.
Tanx alot man 👍🏼 urs was the first video I watched that went straight to the point with clear instructions
Even after 4 years that u post this video, I say thank u
After all searched a lot of video regarding subnet masking got the right one,Thanks this video help me a lot.
After spending a day trying to figure this out yours was the only explanation that's made any sense. Thanks man. BTW you sound like Jamie from Deus Ex.
thank u so very much this concept had been on my nerves and now watching ur video just before finals is something i can't explain....this is so perfect
Thank you very much.I just starting cisco ccna and you helped me understand the concept of subnetting. 👏
This is the first video I've seen that differentiates between the public and private subsets of classes. That finally made a lot of stuff click for me! Thanks!
For those wondering, the top row, is just 256 minus the bottom row... You dont have to memorize it..
my same thoughts
Moe Zuiter
THANK YOU!!!
You can take the 128 and then add the next number under it, then keep adding... so 128 + 64 to get 192. Then add 32 to get 224, etc. So go right to left on the bottom multiplying by 2, then left to right on the top by adding the next number.
awesome one
thank you :)
i just wanna say that out of all the videos that I have seen this the only
one that is making m grasp subnetting great work man!!!!!!!
I tried this method on a past exam paper , and it worked, thank you !
Thank you so much for this! Of all the videos this helped the most. I've found this one of the most confusing subjects in networking.
Thanks again.
Watch "Subnetting is simple" by sunny classroom
You've just unlocked my many years problem within 16 min thank you so much
Great explanation, clear, slow and very precise ! I JUST LEARN SUBNETTING !!!! :))
Your second example just completely threw me off
SBrawlers same here
the second example threw me on
SBrawlers can someone please explain how on the second example the third octet how did he get 255 I'm so lost
This video is an oversimplification of what is actually happening, but it is a helpful video nonetheless.
Subnet-Mask ignores all the IPs below it but leaves all the high numbers(octaves) of what's left for the subnet.
After you get the SubNetMask: 255.255.128.0
Just look at the last two Octaves(Numbers): 128.0
The first 2 octaves don't matter because they've already maxed out, and in the 3rd octave, anything below 128 doesn't matter to the subnet.
Two of those left over IPs must be assigned to identify the subnet itself for delivering data and broadcasting data within the subnet. These are;
1) Network IP: 153.34.128.0 (That's the lowest unmasked value, it starts where the SubNetMask masked it)
2) Broadcast IP: 153.34.255.255 (Note the last two Octaves have gone max value, that's because the SubNetMask isn't stopping it)
The FirstHost and LastHost are just in between those numbers.
yea the second example got me right
this really helped me, and your explanation is so easy it made me laugh after being so confused from sitting in lectures
Jordan,same deal with me. Lol :
Jordan K
1 year ago
this really helped me, and your explanation is so easy it made me laugh after being so confused from sitting in lectures
Explained like a BOSS. No more doubts. Commendable work....
This truly helped...thanks!
you just safe my life in understanding this. thank you very much. May God bless you always.
Thanks for this video. I'm in the process of studying for my CCNA and the subnet mask part was getting confusing for me but this video was a light bulb going on for me.
This helped me a lot, thanks! This was a good tutorial.
Clear and straight to the point. Thank u
This is a great explanation! Thank you!
Thank you for this tutorial it helped clear things up
thank you so much sir.your video helped me alot b4 my practical exam. :-)
thanks man, i really appreciate your tutorial :)
Very informative. IP address and Subnetting simplified :)
I've been struggling with IP addressing all term. I finally get it. This is a clear, straightforward , and thorough explanation. Thank you!
Thanks for this best & clear enlightenment
Very well explained Mr. Khan...Grt video...Thank you.
Thank you, this helped a lot!
great explanation! Love it
OMG this makes sense! Thank you!
Great help on my report. Thanks a lot!!! ❤❤❤
This was great, thank you.
Thanks! Great review
great tut man! just want i needed for my exam
Thanks man! good explaining. well done. thanks
simply gr8...nice and simple
Amazing video and you made it simple with excel...
Thanks man
great work
Really helpful, thanks!
Thanks for taking the time to make the video. I have one criticism though, reading every part verbatim takes up a lot of time and removing this would make future videos more to the point.
Thank you ...u just brief it simply !1
Easy, simple,Nice method to teach
Thanks a lot I understand this better because my professor wasn't explaining this in a way that I was understanding.
Great video. thanks.
excellent helped me ALOT!
Thanks a lot for the class.. :)
Great video!! for a moment i thot RDJ was talkin ! :D
vary good way to calculate the subnet thanks so mach
Amazing explanation.
that is really good training thank you
Excellent teaching
thanks. it was useful
thanks you,really appreciate you help.
it's very helpful
thanks
Good Video!!! Still a little fuzzy about the the subnet mask. If it is a class A IP - will the subnet mask be in the 3rd octect? Or are the last two octects the only ones that can be manipulated?
Great video!
very easy method.....nice work
Thanks for the video
Thank you very much :)
Yeah this was pretty terrible. No real explanation of a lot of the concepts. 'Just remember these numbers' is not useful.
Craig Wallace totally agree, it was horrible. He needs to tie everything back to real concepts. This not a math class
hes expecting you to have a general concept of what your doing he explained that hes not going into depth he was just doing a video to help others but he wasn't going to go into depth so for what it was it was perfect for me, helped me pass my test with the way he explained it so its all about how much you actually know already, if you don't have an understanding in binary and networking your not going to understand anything hes talking about really, hes just helping people who already understand it but are still having trouble with it so hes offering a different solution and i like this solution it helped me a lot.
I agree. Actually, his explanation is somewhat clearer for me than other more detailed, drawn out longer videos. Straight-forward and no fluff works well for me.
most course give the same cheatsheet and do not explain about the how and the why.
very good video, thanks for uploaded in youtube this video thank you very much
Thx dude!
CIDR gives you the number of bits that are 1's starting from the left. Finding the subnet mask from a CIDR is as simple as putting each 8 bit binary string into decimal.
Are you using a mouse or a stapler?
Hole punch?
great concept
Thank you.
Great video! The only thing I'm not getting is... Why did you subtract by 2 to get the last IP in the first example, but subtracted by 1 for the second one?
GOD BLESS you.
Thank you!!!
Excellent..!! @nijer and howitthink
thank you!!
Thank you. :D
There is one thing I have a tiny problem with understanding. 11:35 here you talk about subtracting 2 from 136, why 2? Do we always subtract 2 from the final? Is it because 135 is the broadcast IP and thus we always subtract 2 to get the last available one?
Awesome
thank you
Best explanation ever seen in the internet , for subnetting . Good :-)
Hi! I was wondering what happens if the subnet number is either 8, 16, 24, or 32. Would you subtract it from its own number or does it have to be subtracted from a number that is larger than it?
Respect!
In example 2 there is no mention of the 4th octet, 242, and instead you work with the 3rd octet, 173. Is this to do with the subnet working out in the 3rd octet? As opposed to the first example where everything was done in the 4th octet.
nice video
one of the best vids ever on this subject
Great explanation.. Just need to practice it now. Thanks a lot!
Class A ip adresses are from 1-126and B from 128-191.127 is reserved.
Great Job man. I just have 2 questions. The top row in green? Are those the IP class ranges? And how do the bottom numbers correspond to the top one in green?
Other than that, I got everything down.
Candor please see my video for understanding subnetting in 10 minutes
legend
I'm not sure if this was explained in the video but I just discovered that you don't have to memorize the chart. Just take 2 and keep doubling it to 128 for the top part of the chart you just take 256 and subtracted the bottom number's thus giving you the top numbers.
2^3 is the same as saying double 2, 3 times
Why to memorize ... 255-1=254 but host number start with zero so again add one = 255
Similarly ( 255-2)=253 then 253+1 = 254
(255-8)= 247 then 247+1 = 248
(255-16)=239 then 239+1 =250
Not even need to remember 1 2 4 8 they are in power of 2
2^0
2^1
2^2
And so on
And most important we don't get excel sheet
Still nice job thank you
Question. When getting the subnet mask, where does 255.255.255 come from?
it was easy explanation but i got little confused when you start to do the firs host on the next example. i have to watch over and over hopfully i'll get it . much much better than my stupid cisco teacher
+jetawe gameTV Go watch the Asher Dallas Lecture Subnetting series .. I have watched it over the course of a few days and it has helped me get a really good understanding on how to subnet. it says there are 6 parts but there is only 3 parts available.
+Brenda Mejia i sure will thank you
You didn't explain last host address in detail. All you said was "subtract that by 2".
Maybe it wasnt totally clear, but he kinda explained in the beginning. IS that 2 of the addresses are reserved. One for network address and one for the broadcast address, These are the 2 that you subtract. So lets say you have a network with 64 hosts, but there are only 62 usable host because the network and broadcast address are reserved.
There are some "truths" you learn along the way when learning this stuff. A few of them are:
- The NetID + 1 = The 1st Usable Host IP
- The NetID + the Increment = The *Next NetID*
- The *Next NetID* - 1 = The (previous NetID's) Broadcast IP
- The *Next NetID* - 2 = The (previous NetID's) Last Usable Host IP
how did you get the 17 to subtract it from the 8? is there a way I can find it if I don't have excel? please respond soon
first example has 32 subnets with 8 host per subnet. He needed to list the ranges 0-7, 8-15, 16-23 for this to make sense. The second example is a class B (first 16 bit network, last 16 are host) cidr 17 on class B means ( 16 net, 1 subnet, and 15 host bits) 2^1 = 2 subnets and 2^15= 32768 host/subnet. the 2 (third octet) subnets are 0-127 and 128-255 (NOT 256). A 173 in the third octet fall into the second subnet (128-255). his network id and brocast IPs for this example were correct but his grouping on the right was not depicted well and should not have went to 256. Also he needed to explain the number of host for this example for the numbering (especially in the forth octet) to make sense.
Do a follow up for IPv6 please !!!!
I appreciate your creativity , I followed your way but it fails somewhere because it doesn't have specific formula. for instance Ip
184.136.0.0 /16 , 32-16 or 24-16 which is correct ? i am confused
Hello. What is the total # of hosts on the second example? Is (128*256) - 2 = 32766 the correct answer? Thanks
Rahter tham memorizing all those numbers (128 192 224 ...) just keep in mind that you fill the first 29 bits with 1 and the rest of them you set them on 0. Tadah.