need help subnetting for test

[blackadder1999]

Hi,
If there's anyone out there who's mathematically deficient like me, can you reccomend a good way to subnet for the cisco test? Or maybe a shortcut or some cheater sheet?
Thanks,
Dave

 

[Andyleates]

Dave, my advice is study study study this until it clicks. You absolutley will have to understand how it works - no two ways about it.

It took me ages too, then just one day I went "ah, now I get it". And that was thanks to a damn good instructor.

Andy Leates MCSE CCNA MCP+I

 

[eurobadger]

Hi

http://www.boson.com

used to have a free cheat sheet.

Also if the book you are using isn't getting it across try something like an NT4 Networking Essentials text for a different take on it.


EB

 

[Johns1mpCCNP]

I always thought books did a bad job teaching subnetting. First you must memorize the basic number of networks and the subnet.
subnet network number of hosts
.192 = 2 62
.224 = 6 30
.240 = 14 14
.248 = 30 6
.254 = 62 2

Notice, the number of networks and the number of hosts are the inverse of each other. 6 networks = 30 hosts or 30 hosts equals 6 subnets.

Here is my trick. To find the next network you add one and then double the number. Take 2 networks. Add one, you get 3 and double it to 6. 6 networks is the next. If you take 6 networks, divide it in half and subtract one you get 2. You can do this for any subnet.

 

[rcasta]

Nice math trick, nevertheless I would suggest understanding deeply how subnetting is done (binary code). It's not that hard.

best regards,