Subnet the Easy and Fast way CCNA ICND CCENT

[neuregel]

why does it always seem the best teachers for ip addressing / subnetting are always british?

[manchester90210]

@neuregel

We clearly have too much time on our hands ;-)

[kiran34rk]

nice video,very help full

[VHSyBETA]

i dont get it why he says we MUST always start from 32....

[manchester90210]

When dividing a defined number of subnets from a network we start counting bits from wherever the network mask finished, counting from left to right.

When dividing a Network into as many subnet's as possible but making sure there's a defined number of hosts in each network we start from the end of the address space and counting from right to left, effectively we will always count from the 32nd bit and reserve the host portion as we count from right to left.

Tony.

[Mad2k5]

So, is this all subnetting is?

[manchester90210]

@Mad2k5

Interesting Question.

A Subnet simply put is a method for network enabled devices to calculate wether a destination IP address is on it's LAN or if it needs to send the packet's to the Default Gateway.

Therefore Subnetting is the art of dividing those LANs into Sub LANs. or sub'NET's.

If that is what you meant by your question then my answer is Yes :D

[TaliBruner]

Oh he is Cute!!!!

[hdofu]

I wish my professor made this much sense... he sound kind of like the disney character don carnage.

[mk97000]

Good job mate I like the way you explained it all, thank you

[anura182]

Hey can u help me with this:

Needs 6 department and at lease 60host per subnet....

so which ip class and subnet mask should i use?

Pls Help Thanks



[anura182]

Hey i have problem choosing ip class and subnet.

I have layout everything on this packet tracer file...

Plas Help Me... :[

[Crossmedia101]

That was really helpful.

Do you have more video's?

[sizzletron]

All - Application

People - PRESENTATION

Seem - Session

To - Transport

Need - Network

Data - Data

Processors - Physical

[Wookard]

All  - Application

People - Physical

Seem - Session

To - Transport

Need - Network

Data - Data

Processors - Physical

[megamanx2006]

Mike meyers nemonic jajaja

[eslweb]

Thanks, fantastic video.

[sjipsesjov]

manchester90210 can you explain the OSI model, so it's possible for me, to remember? 

I ask you, because you seem to be a really good instructor, my instructor is not good at all!

Cause I don't want to fail my first Cisco exam :)

[sjipsesjov]

Awesome! But too bad Im not allowed to use any notes to my Cisco exam :S

I must say, It's quite hard to remember all of that, I also have remember the OSI model!

[syedmobinsaeed]

Gr8 ... its really easy now !! Thanks..

[johnmacward]

I'm horribly confused, still stuck at the whole idea of "subnet ZERO", I mean what is it?

[chromatic1976]

this video can be confusing, you have to learn to do it the long way first. Just remember, the whole and only purpose of the subnet mask, is to tell you what part of the ip addres is the network part and what part is the host part, good luck you will eventually get it

[johnmacward]

I do know how do it the full way, but not expertly - I probably need to be "good" at the long way, confident and sure before I get this stuff.

[cmetcalf27]

Thanks! Just one more question. Can I find the broadcast range (network, first host, last host and broadcast) using these charts?

[cmetcalf27]

Thank you for this video. How can I use it to find the number of valid subnets on the network 99.0.0.0/17? Thanks again

[toofarpunk]

/17 is a 255.255.128.0 subnet mask. 99.0.0.0 is a class A. Class A is Network.host.host.host. So if you look at just the host portion of the subnet mask, you have 8+1=9 bits. 2^9=512. 512 is your answer.

[RenegadeFury]

You're a really good teacher, you should make more videos.

[manchester90210]

Why thank you. I'd love to make more videos but I'm crazily busy it seems. I'm still working on financial justification to create a lot more of these types of videos.

[luccass43]

hi sir,

since this table came on show,it made my life a lots easy to understand subnettings,

can u plz help me answer this Q,

how many host addresses are available in the address 172.16.32.0/20.

thanx

[manchester90210]

Your network is a /20 so it has 4 additional bit's of mask. (default for 172.16.x.x is a /16.)

Now what I do is look at the first chart and look at the bit's column until I see '4.' Now it get's even easier, look at column Y0 for total hosts or N0 for usable hosts . Total hosts is 16 or 14 usable. The actual valid range is 172.16.32.1-172.16.32.14. 172.16.32.0 is the subnet identifier and 172.16.32.15 is the broadcast address.

[marlboro2091]

@manchester90210

how ur calculating for /16 then it would be simple... luccass asked /20 which is subnet mask is 255.255.240.0 ...meaning only 12 bits remaining for host .. now wat will be the range? need a answer from u ....

my answer is for 12 .... 172.16.32.1 to 172.16.32.10

[manchester90210]

@marlboro2091 Working with the 3rd byte is exactly the same as working with the 4th. /20 is 4 bit's more than a /16. (remember you are now working with the 3rd Octet, not the 4th.) That will give you chunks of 16. 172.16.0.0 172.16.16.0 172.16.32.0 172.16.48.0 172.16.64.0 etc. Let's look at a range of hosts for one of those networks at random. 172.16.48.1 - 172.16.63.254. The broadcast is 172.16.63.255. For verification convert it to binary and you can see it all works out.

[manchester90210]

@manchester90210 Remember that this video is not designed for peeps who can't work it out using binary. This video speeds up the calculating process. I would need a little longer than 10 minutes to help out anyone who needs to understand IP addressing and subnetting.

However look at the above, think about it and ask me more questions and I'll try to help.

Good luck.

Tony.

[marlboro2091]

@manchester90210

@manchester90210

how ur calculating for /16 then it would be simple... luccass asked /20 which is subnet mask is 255.255.240.0 ...meaning only 12 bits remaining for host .. now wat will be the range? need a answer from u ....

my answer is for 12 .... 172.16.32.1 to 172.16.32.10

[marlboro2091]

@manchester90210

@manchester90210

how ur calculating for /16 then it would be simple... luccass asked /20 which is subnet mask is 255.255.240.0 ...meaning only 12 bits remaining for host .. now wat will be the range? need a answer from u ....

my answer is for 12 .... 172.16.32.1 to 172.16.32.10

[luccass43]

thanx a lots.

[r0q]

I took the CCNA for the first time two weeks ago and even though I knew most of the material, I failed because time ran out. It simply took too long for me to do all the math for the subnetting questions, and it's my hope that I'll pass on my second go around with the help of this video. Thanks!

[manchester90210]

Let me know if I can help further. The primary purpose of this video is to do just that. Speed up your subnetting. It's not so much designed to teach the novice.

[wajdilas]

Thank you very much :-)

[trickywoo56]

Absolutely brilliant - once I grasped it after an hour or so, it revolutionised my speed doing net calculations. Congratulations Sir!

[covatexs]

thank.... this the great video

[tommieb75]

That would be just brilliant! Thanks - I really appreciate this! :) *thumbs up*

[monst4h]

theres something wrong with your subnet excel calculator. The numbers oh host and network bits within the octet do not correspond accordingly. - you need to figure out a way to change this, refer to 7:35 for an example. You say count along 6 host bits, but you count along 7 to get to the 192 address. Therefore your table is flawed.

[manchester90210]

Thanks for your opinion. What others have done before trying to prove the table is flawed is to seek understanding.

I think I said at 7:21 onwards that you need to RESERVE 6 bits for the host portion. This RESERVES 6 bits which is why my netmask falls to the left of the 6th bit. I highlighted the 7th host bit for point of emphasis. What many people do by mistake is count along 6 bits but only reserve 5 bit's.

Maths still stands, table still stands and hopefully you see where I'm coming from.

[monst4h]

Also, from my experience - your inclusion of the 0th subnet is wrong. I had a CCNA skills exam recently, and the 0th subnet does not include the broadcast address. I got 98% instead of 100% as I remembered your tool for subnet calculations of the 0th subnet. Therefore instead of it being 8 subnets, it was 7 subnets. Your calculator is incorrect, please change this. The correct formulae for 0th subnet is 2n-1 !

[manchester90210]

Do you mean subnet 0? If you do then again I must with all politeness state that in my opinion you are wrong. Subnet 0 does contain a broadcast address.

Remember this video is not to teach you how to subnet it's to speed up your ability to subnet.

My understanding and experience of TCP/IP goes back to 1994, so I feel quite comfortable that I know it reasonably well. 11 minutes isn't really enough to convey the full message but the basics are there.

Sorry but there's nothing to correct :D

[HopelessGermantic]

Thanx, hope this is gonna help on the final exams on wednesday...

[UbatuBrasil]

Great video, it's helping me a lot. Any other videos coming? this kicks CBT arse. thanks

[paseaj]

Very, very good. Thanks for sharing. This should be on your guys website, labeled , "Try before you buy." This training video is definitely much more lively than 97% of the other subnetting video out there.

[utube4ccnagoebels]

That was the best training video yet. Please make more.

Thanks,

Pete

[KrazyDawg825]

Can someone explain how Tony comes up with those bits for the octets? Shouldn't they be in ranges of 8?

[manchester90210]

Are you referring to the first chart on the left? If so, that's not representing an Octet, it's pure and simple a binary count.

So the first chart, a 'how many bit's do I need to get the job done' chart. not to be confused with the second chart which IS a representation of an Octet.

For example, how many bit's will I need to steal into the host portion to allow for 2000 Networks? I'll continue from 7 bit's, 8=256, 9=512, 10=1024, 11=2048. Hey Presto I add 11 bit's to the Network address.

[KrazyDawg825]

This is in reference to the 172.16.0.0/16 example given around the 10:08 mark. An octet is 8 bits but it shows 1-7 bits for Octet 1, 8-15 for Octet 2, and 16-23 bits for Octet 3.

[manchester90210]

Hee hee, how about that! I can't believe I put that in but it's there!

I agree with you 100%. I'm trying to figure out how I made such a simple error but hey ho. At least it doesn't affect any of the calculations, theory or application of the charts at least.

Good catch.

Tony.

[mancen10]

Outstanding video, keep it going. You are helping lots of people. Please create more.

[zizyphus99]

You might check out the CISCO Learning site. There's A LOT of good free study info. there. Tony Gibbs has material there in the forums (this video for instance) too. You can't go wrong.

[zizyphus99]

Tony Gibbs is really an excellent communicator. Elsewhere he says to watch this video 10 times and write the chart over and over until it's in your memory. I did it, and he was right. This is a VERY good, time saving technique. And you can't beat the price.

[manchester90210]

Thank you for the compliment, the check's in the post ;-)

Tony.

[Felony7]

you just made my life easier thank you

[pussErox]

this is great thanks! the only part im still having probs with is figuring out the ranges for class c subnets. i can't seem to grasp the concept of leaving one extra bit off each end than you normally would for classes A and B

[manchester90210]

I wish the video was longer too! But YouTube only allow up to 10 mins 59 seconds unless you opened your account before they implemented this rule.

I need to get round to recording a little more plus another one to show you the same chart to work with supernetting. The more people that ask me is more justification for me to spend some time on it!

[KrazyDawg825]

More examples would be great.

[RenegadeFury]

I wish this a was a bit longer, I get it mostly now :D

[dellwon]

I know a much easier way of doing this.

[manchester90210]

There are many ways of working this out. There's easier ways and faster ways, both often involve greater understanding,subtraction, division or multiplication (All of which I avoid.). The exams are stressful & try not to think too hard. The table is also useful for many other IP related questions but I couldn't go through them in 11 minutes.

I have already had a few people show me there way of working out and I think they are fantastic so please do share your knowledge.

[n4vys3a7]

could you please show us how?

[chadsexinton]

Oh god. I still dont get it. WHYYYYYY OH WHYYYYYY?

[manchester90210]

In all fairness this 11 minute video really needs to be 20 minutes to explain it further. Let me know where you are struggling and I'll see if I can help you.

Remember that this training is not intended to teach IP Subnetting, more to take your existing knowledge of how to subnet and get you going faster.

[manchester90210]

p.s I bet it's something quite simple and when we identify where you are struggling everything will click into place.

[pingtampa]

Ye know, I stumbled upon this video by accident and it has been the BEST video/tutorial I have found that solved my binary headache!! I wish you the best and would appreciate if you can extend this to route summarization etc too so we'll be totally clear on the binary math requirements of CCNA.

[nikolassd1]

Why is 15 subnets ???

I think is 16 because 24-8 = 16

[manchester90210]

15 was the requirement not a calculation. It's a sample question that a customer needs 15 different networks due to political or geographical requirements.

Of course you are correct in that you end up with 16 (If Subnet 0 can be used.) Simply use the 15 that was required.

[jaygee1267]

MAN Thanks SOOO FRACKIN MUCH!! that REALLY HELPED ME! Its So EASY.

I took the ccna 1 time before and ran out of time! This should help!

[manchester90210]

Hee hee. A fellow Battlestar Galactica fan.

That's it's design. With this knowledge you will save SOoo much time in the exam.

[AbduAllaah]

Thanks so much!! This really works! Iv only done one subnet question so i still need to check if the A class networks work on this aswell but ace video! You made me well happy!! I have like a 100 pages full of 010101 and still confused about it all. So hope this works, else ill be mail spaming you untill next tuesday. Thanks for the vid mate! well ace!

[manchester90210]

You're welcome.

It will work with any class of address. Remember if you wanted to work with '1000's' of networks or hosts all you need to do is increment the 'bit's required table' to match your requirement. If it works out that you need 10 bit's well that's easy too. simply 10 bit's along from your starting point (for example from a /8 it would be a /18) and hey presto your new mask will end in the 3rd octet and you can continue from there.

[manchester90210]

Hi All, If you found this video useful, let me know what topics you would like to know about and I will create a video for you.

I have been in the Industry since 1989 and in that time worked on almost all aspects of IT and networking. I specialise in security, content networking / Data center Business Video (CCTV, Digital signage, TelePresence etc) so feel free to ask anything and and Maybe I'll dedicate the video to you ;-)

Tony.

[manchester90210]

Fantastic. Glad it helps.

[neilcbsd]

works for me! now i can subnet without the use of subnet calculator!!!!

[macroboid]

gr8 vdo this,

makes for easy understanding of the topic..