CWTS Official Study Guide

[GiddyG]

I work 5 over 4 now, so decided to catch up on some studying in my spare time.

I've been interested in wireless for a while, not least because it's something I think business should be making better use of.

I should add, at this point, that I have 'installed' and maintained networks in my younger days, and I do have the Net+ exam under my belt.

So, I decided to have a look at the CWNP's replacement for the Wireless# certification, the CWTS.

I received the Sybex book through the post a few days ago from amazon.co.uk.

Now this is supposed to be more of an entry level certification. Indeed, the book Introduction says, and I quote:

'The main goal of this book is for you to learn "what it is," not "how it works." That comes later in other CWNP Study Guides...'

As seems to be the case with all Sybex books, it comes with the Assessment Test (30 questions) prior to Chapter 1. There is also a CD, that has demo software programs, Case Studies, Generic Floor Plan, Flashcards, and two bonus exams...

There are 11 chapters to the book, with Review Q&As at the end of each chapter. There is also a handy Glossary and an Index.

I have just finished chapter 4, and this is day 2.

Chapter 1
Gives a gentle intro to WLAN deployment, such as SOHO, public hotspots, and connectivity. It also talks about the various RF regulatory bodies, WLAN standards, such as 802.11g and certifications such as WPA2.0 and WMM.

Chapter 2
Begins by giving a brief overview of layers 1 to 3 of the OSI model with regard to Wireless networking. Moves onto WLAN Infrastructure devices, such as Access Points, Routers, Bridges and PoE.

Chapter 3
Introduces WLAN Client devices. You know the PC Cards, SDIO, CF, PCI and utlities such as the WZC.

Chapter 4
Now we're getting into the heavier stuff... understanding Radio Frequency; Wavelength; Frequency; Coverage; Capacity; Range... RF Behaviour, such as refraction, diffusion, scattering... relative measurements of power, such as Decibel (dB) and Decibel Isotropic (dBi)... and so it goes on.


If anyone thinks CWTS is a walk in the park, think again. But it is very interesting to me, and it may be to some of you.

As an aside, I can't wait for Chapters 8 and 9, which are to do with Planning and Performing a WLAN Site Survey respectively.

Then, there's Chapter 10, about WLAN Security.

As I go through the other chapters, I'll post my thoughts on difficulty and content.

If you do want to know more about the exam, you can visit CWNP.

I'll be booking the exam before Christmas and, if I pass, I'll be moving on to take a look at the CWNA.

[GiddyG]

This is the second part to my overview of the CWTS Official Study Guide...

Chapter 5
In this chapter, we look at the network access methods? Anyone remember CSMA/CD or CSMA/CA? The author puts in a couple of nice anaolgies as well. He goes on to cover FHSS, DSSS, HR/DSSS, OFDM, ERP-OFDM and MIMO, amongst other things.

Chapter 6
This covers WLAN antennas and accessories. I never knew there were so many different types! You have vertical and horizontal beamwidth, active and passive gain. Did you know there's even an antenna called a Yagi? You can get omni-directional, semi-directional, patch, sector...

And, although is WLANs, you have cables. And connectors... different types of connectors, just like wired LANs really.

When siting atennas, you need to be careful to maintina line of sight... and one of the things you have to do when looking at point to point externally is the curvature of the earth... then there's the fresnel zone to cocnern yourself with as well.

And you shouldn't different ways to mount an antenna.

Chapter 7
In this chapter, we delve into WLAN terminology and technology: modes of operation - IBSS, BSS and ESS, RTS/CTS/ACK, Authentication/Association, data rate versus throughput (max rate versus what you are actually getting), Dynamic Rate Switching - change in data rate as distance from AP increases or reduces, WLAN roaming, and more besides.

Some of this, anyone who has done the likes of Net+ will have seen before. But it's great to be abe to think 'I know that!' as you're reading through it.


I'll do a quick overview of Chapters 8 to 11 later this week. Thanks for reading...

[GiddyG]

And so to the next two chapters:

Chapter 8
This chapter concentrates on what you need to look for as part of the 'information gathering' prior to the actual site site survey, from talking to managers and end users, knowing what apps will be used, number of users, location and performance expectations. In addition, there are examples of the type of sites you amy install a WLAN: Office, Warehouse and Military being a few. It also goes through the type of questions to ask, and other documnation you would need. There are also other considerations, such as aesthetics, to conisder as well.

Chapter 9
In this chapter, we read about spectrum and protocol analyzers, active and passive surveys, the type of kit and software required. In addition, there are sections about power and antenna requirements, Multiple and Single Channel Architecture. Very interesting.

[GiddyG]

Chapter 10
Goes through WLAN security, from the early daus of WEP, MAC Address filtering and SSID hiding through to TKIP and CCMP and beyond. there are pieces on RBAC, RADIUS and VPN. There are also sections on WPS and WIPS and more besides.

Chapter 11
And so to the end... and troubleshooting. Identification of various problems from connectivity, through IP address/DHCP, security settings, signal strength and throughput. There is also a section on software and hardware upgrades, and optimization of the WLAN. The piece I found most interesting here was the section on Hidden Nodes.

Conclusion
This is one heck of a book, enjoyable to read and interesting from start to finish. Yes, it is entry level WLAN, but it gives you a real insight into WLAN and sets you up well for the CWTS exam. It is also a fitting prequel to the CWNA Official Study Guide which I also have.

If you want to try the CWTS exam, this book plus the CWNP Online Practice Test (costs about £30) set you up really well. If you don't want to do the exam, but you want a solid intro into WLANs, you wouldn't go far wrong with this book.

I found that the CWNP and TECHEXAMS.net sites have very good forums when it comes to Wireless networking, so they're a useful resource as well.