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Thats right folks,

Passed it today and what a great way to start the weekend!!

Thanks to Coleman, Westcott, Harkins, and Jackman for making a great study guide, and thanks to CWNP community for helping out with questions and for the great discussions.

802.11Chef...a.k.a Pawan Jheeta

Congratulations.

It's a toughy.

Congrats thats a great achievement

Well done 802.11Chef! What other materials besides the official CWSP study guide helped you the most?

1. Read the course objectives, and understand what exactly is being asked
2. The Study guide covers all the necessary materials, but I suggest going on the web and read CWNP white papers, IEEE whitepapers and wifi blogs
3. I used [i]802.11 Wireless Networks: The Definitive Guide by Matthew Gast[/i] as a reference. There are some great in depth explanations that solidify the materials taught in the CWSP guide.
4. Practice tests. Practice, Practice, Practice. Don't try to memorize the questions, rather understand the exam format.
5. Use the CWNP forums. There are many professionals are on this site that are willing to share their insights and expertise

[u][b]You do not need a brain dump to pass[/b][/u]. You should be fine as long as you understand what is stated in the course objectives,

Where's my LIKE button?!? Thanks 802.11Chef. Great advice.

Hi.. I am preparing for CWSP and would be appearing for the test soon. Can anyone pls answer this question for me.

Q. which of the following is a passive device that views current content of the packet travelling on the network?
1. Spectrum analyzer.
2. Protocol Analyzer.
3. WLAN controller
4. Rogue AP.

if the options are incorrect than what would be the correct answer/s ???

Pls help
Thanks
Mz

I suppose you could make your Rogue AP snoop for you, but the answer should be #2 - the protocol analyzer.

The key word is "content".

Imagine that you have a prism and are standing by the window allowing sunshine to pass through it. If the prism is held at the correct angle, we can observe that the white light ?splits up? into components of red, orange, green, blue etc. What appears to be a ?single unit?, i.e. white light, is in fact made up of a number of individual components, which combine to give a composite output.

http://www.thenakedscientists.com/forum/index.php?topic=24878

So it is with RF spectrum analysis. The modulated signals that are used with 802.11 ( and other ) systems are made up of an enormous number of different frequencies. Using electronic filters and sophisticated signal processing procedures ( e.g. Fourier Analysis ), we can begin to ?break up? these signals. If we had a simple signal such as a sawtooth waveform or a square wave, we could actually see individual frequency components. The modulated signals that we use in 802.11 contain so many individual frequencies that an analysis of that depth would not provide much useful information. However, when we input a range of frequencies into a spectrum analyzer ( for example, an entire 2.4 GHz ISM band for example ), we can ?zero in? on a group of frequencies, or ?magnify? to examine one individual frequency ?slot?. There are many controls and options for doing this. By altering the resolution bandwidth of the analyzer, a skilled operator can glean a lot of information. Satellite beacons ( when modulated ) can appear to be just a jumble when appearing on a spectrum analyzer. With careful adjustment of the resolution bandwith and sweep time ( most analyzers have a feature that automatically corrects one dependent variable to another?..sweep time is inversely proportional to the square of the resolution bandwidth ) , individual sidebands can be observed for low values of modulation index.

I was once told by an engineer that a spectrum analyzer is incapable of demodulation. That is not quite true. If a spectrum analyzer is displaying a frequency modulated signal, some units can utilize what is known as ?slope demodulation? mode. He soon changed his mind when I was able to output the audio from a soccer game on a satellite signal that we were observing.

In general, spectrum analyzers allow us to ?see? incoming RF signals. This is ?down?at the physical layer.

Packet analyzers, or frame analyzers ( the two terms have become synonymous these days ) are actually looking at bitstreams. This means that by default, they are looking at the output from a demodulator. Special interface cards and drivers are usually used. If the signal has been encrypted, knowing the key that was used can allow us to see ?deeper into the packet?. These devices can be used for troubleshooting and setting up Wi-Fi sytems etc. They are sometimes known as ?sniffers?. Why ? The human nose is incredibly sensitive?able to detect tiny amounts of odor. When we ?sniff? the air, we process the smell, and if it is known from previous times ( i.e.has been literally stored in memory ), the brain says ?Oh, that?s the smell of roses, that?s the smell of coffee etc? ). Smell has been recognized as the most powerful trigger for memory. Modern memory theory says that we never forget any event ever. It?s all buried in there somewhere. I?m sure everybody has had the experience of smelling something and then having been ?transported?back to a particular event. The smell of hospitals often does that.

These devices are usually passive by nature. In other words not interacting with the other devices in the network. They can be used for ?good?purposes by engineers etc and can also be used for perhaps ?bad?purposes by hackers.

Years ago, most WiFi networks were made up of a number of autonomous or standalone devices called autonomous or ?fat? Access Points. They were called that because they provided a point of access into a ( normally ) wired network to access resources such as databases, mail etc. It was difficult trying to perform configuration changes on each individual AP when you had a large number of them. Monitoring etc could be a headache. Some Wireless Control Systems were in place to help perform some of these functions. For these and a multitude of other reasons, boxes were constructed which acted as a ?master controller?for a bunch of APs. These new APs which worked with the controllers had much of their intelligence removed and were known as ?thin APs?just as when someone loses weight. There are all sorts of controllers around. Some work in a mesh type arrangement where a little less intelligence has been removed from the APs ( or put back !! ) etc. There are more writeups on this than you could ever read in a lifetime. Although each manufacturer will go to great pains to say ?mine is better than yours?, be very careful with all of that. Systems must be tested under ?level playing field conditions?, and even that can be difficult to set up. From a personal point of view, I would say that standalone controllers will always be with us ( many, many units have been sold ), but the ?distributed intelligence? units seem to be the way to go for the future. A lot of this had to do with physical processing cost when APs first appeared on the scene. So, some APs had a lot of ?weight?, lost most of it, then some gained some back on again. Sort of like the Kirstie Allie of the electronics world.

In many corporations when Wi-Fi first came out, employees would often ( sometimes still do, but less so due to security policies, WIDS/WIPS, threat of being fired etc ) sneak a simple wireless router into work and connect it up to an ethernet walljack. This was most often done simply to be more flexible at work. However, this is fraught with a bunch of security issues.

Some people deliberately attach an AP to a company?s network for nefarious purposes. Both scenarios utilize what are known as ?Rogue APs?.

Dave

Thanks heaps guys.

Can anyone tell me how helpful are the dumps that are available online. I have a couple of them and have appeared for the test twice but failed both times at 46 and 62%. I have gone thru the official study guide as was not much dependent on the dumps. But it seems answers to the dumps are wrong.

Has anyone bought any of these dumps and did it help???

thanks
mz