Sub netting Exercises?

sthompson86

Hello all, I am trying to teach myself subnetting, and I have done a pretty good job at doing just that, but I feel like I need more practice. I can do Subnetting, but I feel like I am just not smooth enough yet, for I still have to reference my study book from time to time to resolve a subnetting Network+ problem.

Nonetheless, I am looking for a resource that may have subnetting exerices for me to practice with. Everything I search for on Google for just brings up subnetting guides ect, but what I am actually looking for is subnetting problems to solve. I have done all the ones in my Sybex study book, but I feel like I need some more.

But yea, any good web resources would be appreciated! - Thank you.

hypnotoad

check out the CCNA forum -- subnetting is a huge part of the CCENT & CCNA and a lot of people have posted resources about it.

redline5th

It's definitely something good to practice, but I don't think you actually need to know how to subnet for the Network+ exam. Rather know WHY you would need to subnet, and the general ideas that surround subnetting.

sthompson86

Ok then I will check there.

Since I am on the subject - what about any online subnetting tutorials? seems like everything I run across online confuses the crap out of me. I have a way that I am doing it that works for me, but I would still like to see some notable places where you guys learned and or recommend.

Thanks!

Plantwiz

sthompson86 wrote: »

Ok then I will check there.

Since I am on the subject - what about any online subnetting tutorials? seems like everything I run across online confuses the crap out of me. I have a way that I am doing it that works for me, but I would still like to see some notable places where you guys learned and or recommend.

Thanks!

What have you found?

Typically, Learn To Subnet:  A Free, Lecture-Based Presentation on IP Addressing and Subnetting
Is awesome!!

But so it...
TechExams.net TechNotes
This for practice (checking) TechExams.net - IP Subnet Calculator


I haven't found anyone who had trouble with that first link though, so maybe if you've already been there...it is time to merely review it??

What do you not understand with subnetting? for NET+, you'll need a basic understanding...you won't need to be a master

sthompson86

Plantwiz wrote: »

What have you found?

for NET+, you'll need a basic understanding...you won't need to be a master

Thanks man, what have a I found, Just random videos on youtube thats about it. Thanks for the links.

and yes.. I thought I had to be a master!

Plantwiz

sthompson86 wrote: »

Thanks man, what have a I found, Just random videos on youtube thats about it. Thanks for the links.

and yes.. I thought I had to be a master!

The more you know, the better you'll do in the work environement...which should keep you out of trouble on your exam.

If you desire the Cisco route, then yes, you'll want to Master Subnetting, but if you put your mind to it, I suspect you will find it is not too challenging.

When preparing for your exams, take the opportunity to 'learn' the material if it is new to you rather then merely putting up the old 'high school (or even today's college try) with the material. IT skills tend to build on one another, and if you skimp in one area, you'll be 'stuck' putting more time into it at a later point (which could slow your progress).

Learn all you can!

sthompson86

Plantwiz wrote: »

If you desire the Cisco route, then yes, you'll want to Master Subnetting, but if you put your mind to it, I suspect you will find it is not too challenging.

O yea, I headed towards CCNA after Sec+ - Thanks

dancreaney

Try subnettingquestions.com - Free Subnetting Questions and Answers Randomly Generated Online

sthompson86

dancreaney wrote: »

Try subnettingquestions.com - Free Subnetting Questions and Answers Randomly Generated Online

Thats what I need thanks!

skwira001

sthompson86 wrote: »

Hello all, I am trying to teach myself subnetting, and I have done a pretty good job at doing just that, but I feel like I need more practice. I can do Subnetting, but I feel like I am just not smooth enough yet, for I still have to reference my study book from time to time to resolve a subnetting Network+ problem.

Nonetheless, I am looking for a resource that may have subnetting exerices for me to practice with. Everything I search for on Google for just brings up subnetting guides ect, but what I am actually looking for is subnetting problems to solve. I have done all the ones in my Sybex study book, but I feel like I need some more.

But yea, any good web resources would be appreciated! - Thank you.

You will not need to know any subnetting besides subnet masks that are all 0's or 255's in an octet.

If you want to know a good trick, I don't use that 2^N formula. I think it's the dumbest formula I've ever seen. If you have a calculator, then that's the way you do it. When you're doing it by hand, who is going to remember what 2^5 is? Here's a better way.

Q. You need 25 hosts per subnet. Find the subnet mask.
A. Automatically, I know that the boundary between network and host is going to be in the last octet since using all 0's in the last octet gives me 256-2=254. So here's what I'll do:
256 128 64 32 16 8 4 2
128 64 32 16 8 4 2 1
255.255.255. 1 1 1 1 0 0 0 0

You start at 256 above the 128 value. You should automatically know that 2^8=256. That I would memorize. I began at 256 and divided by 2 each time I went to the right. The numbers on the top is the number of hosts per subnet before you subtract 2. I need to top the 1's at the 32 because 16-2 does not give me enough hosts but 32-2 does. If you're going across octets, say you need 500 hosts, you can just begin at 2, go from right to left, and keep doubling until you reach or first excede the number of hosts you need. Then write the binary placeholder underneath.

For networks, you do just the opposite. You go like this. You need 25 networks. Automatically, we know we can squeeze out 256 networks if subnet 0 is allowed. If subnet 0 is not allowed, it's 254 networks.
2 4 8 16 32 64 128 256
128 64 32 16 8 4 2 1
255.255.255.1 1 1 1 1 0 0 0

Basically the top numbers in each of these is 2^N. That's essentially what you're calculating.

Now just take the binary values in the lats octet in each subnet and add them up.

If you have to jump octets, just keep doubling. You'll always begin with 2 for networks going left to right. If you're subnetting a class B network, you'll begin in the third octet rather than the last for octets. It's really important to know what the default class is when it says you need this many networks. For hosts, not as important unless the problem requires that you need more than the hosts than the default class will allow. In that case, you supernet.