Poll: What Resource is the best way to learn Subnetting

Hey guys. I wanted to know what you think the best way to subnet is. It seems like there are so many different approachs, I felt that it would be helpful to see what everyone thought was the best way for them.

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Comments

nel

For me, odoms explanation in the icnd1 book made it plain and simple. obviously know the ground work and how subnetting logically works using binary but i found using the decimal approach to figure out subnetting was the most efficient method for me in terms of timing for the exams.

That along with plenty of practice on subnetting questions.com was enough for me and it played well in my ccent exam.

dave0212

The explanation in Sybex CCNA Fifth Edition (801) worked for me, and then once you understand just practice, practice, practice

I felt I was ready when I could do them in my head at a very quick rate. Not done it for a while though and will need to brush up ready for renewal

kevin31

Hi

Ive tried few books! train signal videos give a good way to do it.

How you do it in your head I seat there for 10 minutes working out the binary first???

dave0212

Mental arithmetic has always been one of my strong skills, so I spent about a week just practicing. I also spent alot of time doing Binary/Decimal/Hex translations and could go from one to the other fairly quickly. Mainly because when I studied for the CCNA the biggest issue people moaned about was time so I wanted to ensure I could do the calculations without the slow binary conversions.

It may have just been the exam I got but finished in 60 mins, 3 sims and 949 scored

And I've got to it all again within the next 12 months

nel

kevin31 wrote:

Hi

Ive tried few books! train signal videos give a good way to do it.

How you do it in your head I seat there for 10 minutes working out the binary first???

Practice, maths calculations arent my strong point which is why i practiced the decimal way (you basically take the SM away from a "magic number" and it allows you to work it out in a decimal format). Sadly you dont get 10 minutes to work out subnetting in the exams

most people recommend being able to do it within 10 - 15 secs.

dynamik

Chris Bryant (www.thebryantadvantage.com) and James Conrad (CBT Nuggets) have been the best so far. They make's Odom's in ICND1 seem overly complex. No magic numbers and crap like that (sorry Nel

TryPingingTheServer

dynamik wrote:

Chris Bryant (www.thebryantadvantage.com) and James Conrad (CBT Nuggets) have been the best so far. They make's Odom's in ICND1 seem overly complex. No magic numbers and crap like that (sorry Nel ).

I concur with the Odom statement, but the rest of the book is solid gold. Todd's section on subnetting has its moments.

Kaminsky

pencil and paper.

Initially, write out the full 4 octect binaries and how subnetting works just leaps off the page at you. That get's you're brain understanding what's going on rather than just arbitrary numbers. The is the quickest way to ge tthe concept to "click" in your brain.

Do this with your own, made up, subnets rather than a book or do the full binary math on the questions on subnettingquestions.com.

Once you have the principals in your mind, the rest is just practice and practice and practice.

It is true that with enough practice, you can do these in your head within seconds whether you are good at mental arithmetic or not. You're average question you can get down to under 10 seconds and the harder ones, about 30-40 seconds.

This is one of those topics you cannot **** at. You have either done the hard work or you haven't. If you haven't then it will cost you as subnetting is everywhere and if you can shave of exam seconds because you have done the work on these, all the better. If you haven't, you will struggle for time.

Kam.

nel

dynamik wrote:

Chris Bryant (www.thebryantadvantage.com) and James Conrad (CBT Nuggets) have been the best so far. They make's Odom's in ICND1 seem overly complex. No magic numbers and crap like that (sorry Nel ).

Well were not friends anymore

..no seriously though, i'll check out the sybex one as i have that book, its just odoms done it first time with me but then again if it aint broke dont fix it !

billyr

Another one for Chris Bryant. His pdf workbooklet that comes with his courseware is excellent.
As said before no magic numbers or tricks etc, just practice, practice, practice.

Sorry to say I didn't pay for it though, I borrowed it from a mate. Sorry Chris.

aragoen_celtdra

If I can just add mine in... for me Odom's way gave me the best explanation for the mechanisms under this whole subnetting thing. Lammle taught me how to do it quick. In short, to know the why for subnetting, Odom is my guy. The best "how-to" approach, I would go with Lammle.

Truthfully though, everyone here seems to have their own preference, and not one of them could go wrong.

Hope this adds to all the madness in your decision-making process