Forum

Correct me if I'm wrong, but no actual products use DSSS-OFDM. So why worry about it?

Ben,

Just because nobody has implemented something yet isn't a license to say, "let's forget it." We've had this same discussion concerning PCF mode...no products have implemented it, so it must be worthless and dead. NOT TRUE at all. Suddenly, the standards designers have decided to resurrect PCF in the forthcoming 802.11e standard in an enhanced mode called HCF. HCF might or might not be used, but it's well designed and you (nor anyone else) can tell the future of this industry.

You made the same argument over 802.11a phones, saying that since they don't yet exist, that we shouldn't even consider them. I wholeheartedly disagree. They're coming. 802.11a is better than 802.11b or 802.11g in a number of ways. I don't doubt that we'll also see MIMO phones. They aren't here yet, so why worry about them, right? I say we should consider these things so that we'll know what they're for, how they will be best used, and their advantages/disadvantages in the market when/if they do arrive.

If you live only in the *here and now* then you'll miss lots of valuable information in this industry.

Devinator

Devin,

I'll bet you $1 that no vendor supports HCF on both the infrastructure and end-user side in the first year after 802.11e is ratified.

To your general point, you are right to a degree. It is a very good idea to understand and promote potential features that don't yet exist. Where we have a disconnect is in requiring potential certification candidates to intimately understand paper theory.

It is one thing to say that people should think about 802.11a VoIP phones. There is a good chance that we'll see them at some point. But things like DSSS-OFDM and PCF mode? Sure, it's good for a certification candidate to understand them at a high level, but where's the need to understand every little detail? They've been an option for years now, and nobody does (or likely ever will) support them.

It may not seem like it, but I am trying to help you guys. I have probably taught more CWAP classes than every other CWNT combined. As you know, it's my favorite CWNP class to teach by far. I see far more interest in getting certified from students BEFORE we start class than I do afterwards. I know that is just the nature of difficult certifications in general, but I really get a sense that students recoil at the notion of having to spend so much time studying on topics like DSSS-OFDM that will almost certainly NEVER leave the world of paper theory.

Let's take Electrical Engineers for an example....

There are lots of them in the world, and they spend 4-5 years earning a degree that is filled with EMag classes, Calculus classes, Antenna theory classes, etc. They may end up working as an EET (a more hands-on position that is half way between an EE and an ET). In a position like this, they could easily say, "Why did i blow 4 years learning EMag, Calc, and Antennas?" This is the point of view you a presenting, and while valid, it's not the ONLY point of view.

This same EE could also get a job at IBM in their research department designing never-before-seen storage and computing devices using protocols, tools, and theory that they learned during all of those theory classes. They wouldn't be singing the same tune as the EET, I assure you. The validity of the material presented in the CWNP Program is relative to the job position you are in after receiving the education.

If you attend the CWAP class and then land in an SE job with DLink, then you may or may not use some or all of the things you learned in CWAP. If you go to work for AirMagnet as an SE, then you will have to know everything in CWAP plus likely much more. The engineers from AirMagnet, Network Chemistry, Aruba Networks, and others that have been in my CWAP classes have paid strict attention to even the PHY header information which, to some, might seem too detailed. The reason for paying strict attention to details at this level are due to security attacks and throughput issues arising from issues presented at this level.

I see your point, but I have to say that not everyone fits into your mold. We have to teach a broad array of technicians and engineers, and we can't have 20 different kinds of 1 day classes catered to each job role. :-)

Devinator

Hey, man. I see where you are coming from. Just remember, though, you can't compare certification to a 4 year degree. They are two ENTIRELY different things.

BenMiller you must be a EE !


CWAP-Paper Theory ? Please elaborate further, help us that are studying understand the students frustrations.

You say you teach this and you have more students reluctant to certify after the class than before. Please share.

Because you love teaching CWAP. Will you share your tips to success on the exam?


Regards

Ben Miller Escribi?3:

Correct me if I'm wrong, but no actual products use DSSS-OFDM. So why worry about it?

For blueice it seems that passing the test is part of the larger goal of completely understanding 802.11X. I applaud the effort. Keep asking the questions blueice.

I also want to understand the marketplace today so keep pointing out the reality Ben Miller.

Thanks,

moe

I did a degree in EEE about 6 years ago, so I've forgotten quite a lot things, since I've not been working in this field. That's why I tend to ask some basic questions.

What I've noticed in the study guide is that some things have not been included, the reason being, I guess, not to make it too complicated for those who not have an EE background.

For example, I'm still trying to understand the meaning of carrier frequency, its relation with channel center frequency, ...

Maybe I won't have the time to do that since I'm taking the exam on Monday...