Is the Sybex book giving me the wrong answers?

I`m just working through some subnetting question using Tod Lammle CCNA intro book.

I`m stuck on this question: question on pg141 answer on pg 149

what is the subnet, broadcast address and valid host range for:
192.168.100.66/27

his answer is:
host is on the 32 subnet,
broadcast is 63
host range is 33-62

I get the following:
subnet 192.168.100.64
Broadcast 192.168.100.95
Host Range 192.168.100.65-94

Who is correct, because no matter how many times I do this I come up with the same answer, I need to know if I`m doing it correct or wrong.

Thanks, Nick

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Comments

Kenjin

I just downloaded the Sub net calculator from this site and it seems that I am right!! whats going on with this book?? I just spent the last 40 minutes panicking thinking I was really screwing something up

networker050184

I have heard a few people complaining about the book being inacurrate. I used the cisco press mostly when I studied. I had the Lammle book for the combined but I wasn't very impressed. Just make sure you verify the answers to all the questions. You don't wnat to learn the wrong info!

Spudage

Remember that Cisco have downloadable Errata for most of their published books, so if you encounter something you think doesn't sound right, check the updates first before doubting yourself.

rakem

you are Correct.

the book has figured out the question for the subnet below.

If the IP addresses was something like 192.168.100.46 then the book would be correct.

Netstudent

You can also download the errata from the sybex website if thats what you are using. There are also PDF's that expand on the CCNA topics that arn't covered in detail in Sybex. Like NAT.

Netwurk

Whether you use Cisco or Sybex or O'Reilly, you're going to get some errors in a book. They all have good errata sections on their websites.

The Cisco Press book I'm reading now wants me to work with a netmask of 255.255.255.255.128

Not sure how I'm going to do that

Anyhow, they all make mistakes. It proves that you're learning when you catch something the proofreaders missed.

bighornsheep

Which Lammle book and what edition are you using?

I own the INTRO (640-821) book and I dont have that question, I just in the 5th edition of the CCNA (640-801) book published in 2005 and I see this:

Was it q.8 in the written lab for ch. 3?

192.168.100.66 255.255.255.224: Subnet is 192.168.100.64, broadcast is 192.168.100.95, and valid host range is 192.168.100.65 through 94.

256 - 224 = 32. 32 + 32 = 64, plus 32 = 96. Subnet is 100.64, and broadcast is 100.95.

weird...