Forum

To anyone studying for the CWNA exam [ or indeed anyone interested in 802.11 ], I would strongly suggest signing up for the Wi-Fi ???¡é?¡é?????¡­?¡°Question of the Day???¡é?¡é????????.

These questions are not some old rubbish thrown together at the last minute. They are very well thought out questions. With many of them I have had to really read the question several times in order to ???¡é?¡é?????¡­?¡°not get caught out???¡é?¡é????????. My ever ready mouse trigger finger has many times been just about to "tick" one of the option boxes, when something has told me to re-read the question.

They add a lot of useful little details that are hard to find elsewere [ chunks of info from the spec etc ].

What I do is to open a Microsoft Word document and copy and paste the question [ along with the optional answers ]. You can include the "tick"marks once you have the question answered correctly.

If you look down at the bottom of the frame, you will see a little link saying ???¡é?¡é?????¡­?¡°Show Explanation???¡é?¡é????????. If you click on this, it will show you detailed information about the correct answers.

On my system, it appears behind my main browser window and I just bring it ???¡é?¡é?????¡­?¡°to the front???¡é?¡é????????.

I copy the detailed explanation and increase the font size so that I can see everything nice and clear.

I have broken the word document [ now documentS !! ] into two main parts :general 802.11 and security.

For the real tricky ones, I change the font color to red. This then gives me a good on-screen reference.

Kudos to whoever thinks up these questions. Some of them are pretty tough, and I can see that a lot of work goes into ???¡é?¡é?????¡­?¡°thinking them up???¡é?¡é????????.

Dave

Hi Dave,
Thanks for the info on the Wi-Fi "question of the day". I tried to look around on the cwnp.com on how to sign-up for the Wi-Fi "question of the day". I didn't get it. Can u tell me how to go about signing up?

It's a Google Gadget that you can add to your iGoogle page, or a widget you can add to any web site:

http://www.widgetbox.com/widget/cwnp-wi-fi-question-of-the-day

Here???¡é?¡é?????¡é???¡és a nice example from today:


The Question
You are troubleshooting a closed wireless network that is WEP secured. Which of the following things could you expect to see with a wireless protocol analyzer?

(Choose 3)

A
Wireless management and control frames.

B
MAC addresses of the wireless stations.

C
SSID information.

D
IP addresses of the wireless stations.

E
LLC Layer headers of the wireless stations.


The Detailed Explanation


While many wireless protocol analyzers can see OSI layers 2-7 (and parts of layer 1), layers 3-7 will be shown as WEP encrypted packets (unless the analyzer has been provided with the WEP key.) Only information found in layer 2 headers such as wireless management and control frames, wireless station MAC addresses, and SSID information will be seen.
IP addresses are found at layer 3, and would be WEP encrypted. In a 'closed' wireless network, the SSID information is removed from beacons, however it is still available in other layer 2 packets, such as probe requests and responses, and association and reassociation requests.


Just after getting up, fired up the old PC and took a quick glance. First thoughts into my befuddled coffee-less brain were ???¡é?¡é?????¡­?¡°OK, WEP is going on here, so no peeking at any payload info [ without the key ]. IP and LLC are out. Closed network, so no SSID broadcasting. Just about to click the first two, when my ???¡é?¡é?????¡­?¡°warning light???¡é?¡é???????? went on. Hmmmm.. Too easy. Stop right there. What about probes etc. ? ???¡é?¡é?????¡­?¡°Closed???¡é?¡é???????? should be really be called ???¡é?¡é?????¡­?¡°Door PARTLY closed???¡é?¡é????????. Clicked on item 3 which I would have missed if I hadn???¡é?¡é?????¡é???¡ét paused for a minute and really thought it out.

When we are nice and relaxed at home, these little ???¡é?¡é?????¡­?¡°tricks???¡é?¡é???????? might not seem like much, but under the stress of an exam, they can really catch you. One thing I have learned about these QOD???¡é?¡é?????¡é???¡és is that you really have to read the question more than once, then stop and really think.

Dave

Thanks Dave. Did your "warning light" go on because you had only picked two and the question says Choose 3?

I've found after doing these questions for a few months that I get a "gut feel" when I don't have all the correct answers.

I read the part about ticking the three responses, but go so side tracked with the SSID business that I was about to leave just two answers ticked. The system won't let you do that, but if it did, I would probably have just clicked the first two. These questions are really very well thought out.

I have to force myself to slow down and read and re-read the questions and possible responses.

I used a process of elimination. Knew that the first two were definitely correct. Payload is encrypted, so that got rid of the last two. I had just gotten up and my mind couldn't remember that SSID's can be shown in probe requests/probe responses etc. It took a while before I remembered.

Dave