TCP/IP Subnetting Made Easy 640-801 Test Questions Guaranteed pass

Let's use the IP address of 200.156.136.89/27. First of all we can see that this is a Class C address, and the /27 indicates that we have 27 bits turned on in the subnet mask. Counting in binary we can see that the subnet ID is 224.

128 + 64 + 32 = 224.

Decimal	128	64	32	16	8	4	2	1
Binary	1	1	1	0	0	0	0	0

The following table identifies the network ID in increments of 32, the host range and the directed broadcast address for each subnet.

Network number	Host range	Broadcast address
200.156.136.0	200.156.136.1 thru 200.156.136.30	200.156.136.31
200.156.136.32	200.156.136.33 thru 200.156.136.62	200.156.136.63
200.156.136.64	200.156.136.65 thru 200.156.136.94	200.156.136.95
200.156.136.96	200.156.136.97 thru 200.156.136.126	200.156.136.127
200.156.136.128	200.156.136.129 thru 200.156.136.158	200.156.136.159
200.156.136.160	200.156.136.161 thru 200.156.136.190	200.156.136.191
200.156.136.192	200.156.136.193 thru 200.156.136.222	200.156.136.223
200.156.136.224	200.156.136.225 thru 200.156.136.254	200.156.136.255

This illustrates the long way of doing things, and if following this method you will very likely have a time with the Cisco® CCNA exam, and even possibly the Microsoft® 2003 certification exams.Consider having to identify the network ID with a 255.255.255.252 mask and the directed broadcast address when there are 50 subnets and having to create a table like this.
Time consuming to say the least, and to do that with 4 to 7 questions on a Cisco® CCNA exam or even a Microsoft® 2003 test. That will surely eat into your valuable time.
Try the following; get a pencil and paper and identify the network ID and the directed broadcast for 156.78.221.223/22.

Did you come up with:

Network ID 156.78.220.0
Host range 156.78.220.1 through 156.78.223.254
Directed broadcast 156.78.223.255
There are a total of 1022 usable (valid) IP adddresses in this range!

If you can't, solve a subnetting problem like this without a calculator, or it is time consuming and you want to be a Network Administrator, or tackle the Cisco® CCNA, or Microsoft® 70-291 exam then this book may be for you.
I cannot imagine creating a table for all of these subnets for one simple question, let alone let's say 5 questions on one exam! Our method will solve problems like this in less than a 60 seconds, with no tables, and no calculator!
Not only are the Cisco® CCNA and Microsoft® 70-291 tests tough, but you have to have subnetting nailed down!

Our two step method does not require a calculator, (which is not allowable on a Cisco® exam), does not require cumbersome tables, and the math is simple division and multiplication with whole numbers! Simply put it is amazing.

Subnetting Made Easy