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Hi folks,

I am searching for a well-written book on 802.11 site surveys which includes specific treatment of 802.11n. Would appreciate suggestions. I am aware some organizations offer full-fledged training courses that cover 802.11n. However, this query is for some people who want to begin small by just exploring the concepts, and then moving on to bigger things if required.

Thanks!

First - I've been teaching, consulting, and performing Site Surveys for many many years now.

Second - over a year ago I developed a specific course, and have been teaching and consulting on 802.11n issues.

Your problem is many-fold.

I've seen atrocious Wireless LAN installs - because people just didn't understand how 802.11 actually works, so they 'did their best' and did an 'AP on a Stick' site survey thinking what they wanted was coverage.

The actually differences between 802.11a/b/g and 802.11n are STAGGERING! Not in the baseline concepts and underlying technology, but in the implementation.

802.11n is COMPLEX, very very complex. Don't even attempt to learn it directly. First get a good, no, a great understanding of 802.11a/b/g first - then you might start down the path of learning the 'extra' stuff in 802.11n.

Do you want to learn 802.11n Wireless Network DESIGN? Or did you just want to know about some 'tricks' on how to perform a Site Survey for 802.11n?

I have a three-page questionnaire I use in my first consulting engagement meeting with a client *just* to find out what they *might* want their Wireless Network to do. So I won't be able to ask you all the questions here...

But you need to REALLY know what you want, what your expectations are, not just for the wireless component, but just as important, what it is going to do to your wired infrastructure.

I thought of writing the book you asked for... but it would HAVE TO be an add-on to first learning all you can about 802.11 (try David & David's CWNA Sybex Study Guide for a great book on that)

Then you need to learn how to *properly* do wireless network design. Design to meet specific client based needs, and then add to it knowledge of how 802.11n works.

Then finally, with all that knowledge (and answers to all the questions pertaining to what your client wants their Wireless LAN to accomplish, greenfield vs transition, client types, wired infrastructure, PoE requirements, cabling updates, switch fabric updates, antenna patterns, location tracking needs, vendor choices, vendor specific requirements, etc.

Then, and only then will you be able to accurately design and implement an working 802.11n wireless network.

(oh, and did I mention you also have to upgrade the client base to 802.11n as well in order to meet some of the wireless LAN needs and specs?)

-----------

Or - Design for 802.11a, install 802.11n and be done with it.

Hi Keith

Your statement below:

"Or - Design for 802.11a, install 802.11n and be done with it."

ARe you sating that if you deploy 11n in the 5GHz spectrum, you can perform an 11a survey and deploy 11n and have a reasonably accurate survey and design?

CP

bigcontractboy Escribi?3:

Hi Keith

Your statement below:

"Or - Design for 802.11a, install 802.11n and be done with it."

ARe you sating that if you deploy 11n in the 5GHz spectrum, you can perform an 11a survey and deploy 11n and have a reasonably accurate survey and design?

CP

We had luck with that approach here for our 11n deployment, but there were no 11n site survey tools available at the time. We were also using Meru's SCA, so we didn't have to worry about co-channel interference and power levels on the radios.

Hi Matt

We too use a SCA manufacturer, Extricom. SO the channel issues dont really affect us, however with the cost of 11n equipment your wouldnt want too much of an over kill.
With Meru, how do you find their coverage compares on the 11n to the 11a kit in a normal office environment?

CP

bigcontractboy Escribi?3:

Hi Matt

We too use a SCA manufacturer, Extricom. SO the channel issues dont really affect us, however with the cost of 11n equipment your wouldnt want too much of an over kill.
With Meru, how do you find their coverage compares on the 11n to the 11a kit in a normal office environment?

CP

I wish I had a good number, but the coverage is significantly greater. With 11n it isn't an exact 20% greater or whatever, but I have definitely seen improved range of up to 30-40% in some cases.

keithparsons Escribi?3:

Do you want to learn 802.11n Wireless Network DESIGN? Or did you just want to know about some 'tricks' on how to perform a Site Survey for 802.11n?

Keith, thanks for those insights. May be I should elaborate a bit. This book is intended for some colleagues of mine who are basically Networking systems driver developers. They are strong in 802.11a/b/g, and quite conversant with 802.11n. However, a developer???¡é?¡é?????¡é???¡és focus tends to be more on protocol implementation, driver design, OS interfacing, configuration application UI, and so on. They would like to get a wider perspective on site surveys, so that they can design the software better and also provide stronger support to field engineers. (One of them might even consider getting more involved with site surveys in years to come because there is a lot of potential in these parts).

I guess my 'flippant' answer at the end of my post might have have been mis-interpreted.

I was 'trying' to re-enforce the idea:

IF "you don't know exactly what you are designing for..."

THEN "Design for 802.11a, install 802.11n and be done with it"

Again - It is *far* more important to know *what* you are designing for, than how you design.

You CAN NOT design for merely RSSI and then expect your wireless LAN to perform properly!

It's all the other factors that really count.

I like to quote the Cheshire Cat from Alice in Wonderland. "If you don't know where you are going, then any road will take you there"

With respect to Wireless LANs - how can you expect to meet the user's goals/expectations if you don't know what they are.

I'm just fed up, and tired of going behind folks who designed for RSSI, delivered RSSI, and then the client calls me to 'fix' their Wireless LAN so it actually performs for the them.

The goal of any post-install site survey should be to 'prove' the Wireless LAN does what it was designed for.

EVERY SINGLE WIRELESS LAN *MUST* have a Post-Install Survey completed!

You might also want to do a pre-install survey...

Sorry - I don't know of any book that could help your engineers. Perhaps actually having them leave their cubicles and go in the field and do a couple post-install surveys to see how the RF Propagation and see how users are using the Wireless LAN could be invaluable for their education.[/quote]