Blog

Get the Newest Blog Direct to your Inbox

* indicates required
  • CWNP

Just What The Wi-Fi Doctor Ordered: AirMedic

Well it's about time someone did this.  First there was nothing.  Then the Cadillac of Laptop-based spectrum analyzers came along: Cognio...to this day, still unrivaled.  Then Cisco scarfed up Cognio and the honeymoon between cash-strapped users and a bleeding-edge startup ended...  You want Spectrum Analysis, you pay.  Not unexpected of course.

Then those same self-funded users turned to the low-end alternative: MetaGeek's Wi-Spy.   For 10% of the price of Cisco's Spectrum Expert, you too can have very basic spectrum analysis in the 2.4 GHz band only.  What was that?  Oh yes, that's right..."you get what you pay for."  Rats.  If 'basic' and '2.4 GHz-only' will do ya, then you're all set with Wi-Spy.  But what if you need more but can't shell out $4k/license?  Well, you are just stuck.  Grrr.

 

Continue reading...

  • CWNP

Dynamic Protection Mechanisms

Protection mechanisms are essential to the interoperability of multiple PHY's, like 802.11b on an 802.11g network. The problem with protection mechanisms is that they are very static, either on or off. Either you don't allow a "mixed mode" environment or your do allow it and consequently run the risk of losing 40+% of your throughput. What is the answer you ask?

 

Continue reading...

  • CWNP

Much Ado About Where

First, there was a defensive strategy: Meru's RF Barrier.  Very nice.  Then, Agito added locationing to their systems whereby each phone can "calibrate" areas in such a way that they're drawing a physical line of where/when to move to/from cell tower to/from Wi-Fi network.  No scanning-for-WiFi all the time (saving battery life) because when you get to a certain cell tower, you know you're "at home" or "at work" and start looking for Wi-Fi.  Seriously cool.  Now, I'm hearing talk of adding "where" to system authentication.  No longer will it be enough to have your username/password (and/or other credentials)...now you have to physically be in the right location also.  WAY Cool!  Why so much focus on "where?"

 

Continue reading...

  • CWNP

Nigh Wi-Fi

http://www.ubnt.com/products/

Ubiquiti builds some neat stuff, I have to tell you.  I have a couple of their products.  Unique, compatible, powerful, simple to use.  But full-featured 802.11 radios, compliant with the various 802.11 amendments that live in the 700 and 900 MHz bands?  What?  "Based on 802.11g OFDM" the specs say.  Take note of the 600 mW output power on that 700 mW radio.  Yikes!

I hadn't really considered this type of thing until a CWNE friend of mine started checking out some new mesh products.  He asked me about the positives and negatives of such a thing, and the first thing I thought of was interoperability and analysis.   The Wi-Fi Alliance is only interoperability testing and certifying equipment operating in 2.4 and 5 GHz.  So, 700 MHz (public safety), 4.9 GHz (public safety), and 900 MHz (ISM) is kind of left out in the cold for now.  Additionally, analyzer vendors don't make drivers for cards that work in non-Wi-Fi bands, so site surveying, protocol analysis, and spectrum analysis is out.  That would mean you'd be flying blind.  No thanks.  Been there, done that.

 

Continue reading...

  • CWNP

MIMO 4x4 with TxBF Has Arrived - Dang That Was Fast!

http://www.quantenna.com/products-overview.html
 
Yep, my good friend Dilip Advani (CWNE #43) pointed this out to me recently.  Can you believe it?  Before long, we'll have data rates hitting 600 Mbps, with throughputs that will still be under 100 Mbps. :)  We'll have Beamforming, which will change how we wrestle with co-channel interference.  Beamforming will give us higher throughput at range and will stabilize our RF environment significantly.  This is GREAT news indeed!

My advice to IT Managers: When you see this stuff hit the market with a Wi-Fi Alliance sticker on it, find any excuse possible to throw 802.11a/b/g gear out the window (or sell it on eBay).  Obviously these new 802.11n chipsets will support 802.11r/k when the Wi-Fi Alliance version is released as "Voice-Enterprise", and likely whatever new standards are released for the next 3-4 years as well.  

How fast will vendors adopt these new chipsets?  Unknown.  You know, it's alot like 802.11r/k in fact - it'll all depend on the Wi-Fi Alliance's willingness to build and implement a test plan.  A year?  Two?  The standard is already in place, but that seems to matter very little, which is a bit irritating (though I certainly understand why things are the way they are).  I, like most everyone else, want everything now. ;) 
Continue reading...

  • CWNP

Customer Service...Hmph...You Ain't Seen Nothin'

I just got back from Ruckus Wireless's First Annual Big Dogs Conference.  It was the best thing since...sliced cheese. (inside joke)  Two long days of back-to-back meetings, but these were no ordinary meetings, and this was no ordinary conference.  Dreamed up, brought to fruition, and even MC'd by Ruckus's own David Callisch and his team of marketing geniuses (including June Eidson and Lisa Lavarias), this was a chance for Ruckus's customers, partners, employees (including all senior management and top engineers), and others with a vested interest to pour into one gigantic place to get to know each other, to share their knowledge and problems, and to become something akin to Ruckus family.

Now I have to tell you that Ruckus, for such a small company, knows how to treat its customers and partners.  Holy cow batman.  They spared no expense.  I felt like royalty, and for a country boy from Bremen, GA (yes, it's actually on Google Maps), it was...um..."off the hook...or chain...or whatever that saying is."  There were roadmap sessions (Niv kicked butt), sessions on RF design (Victor just rules), and my personal favorite: The Firing Line.  Yes, it's just what it sounds like.  CXO's and VP's were on stage taking pot shots from the quite-large audience for over an hour.  No question was off limits, and they did their best and were transparent and honest.  Big Kudos.

 

Continue reading...

  • CWNP

The Right Amount of Power

We've all heard, "Turn the power down, shrink the cell size, and you'll get more aggregate capacity in your Wi-Fi network."  It's an incomplete and bogus statement.  I know, you're thinking, "OK, Mr. Smarty Pants, where are you going with this...?"  First, consider that Cisco's VoWLAN 4.1 Design Guide, Page 3-3, starting with the section entitled, "Co-channel Interference Considerations" starts on a 15-page commentary that spells out in great detail something that it sums up in the beginning by saying, "The reality is somewhat more complicated because the AP influences the WLAN RF environment around it for a much greater distance than just the bit-rate boundary."  I give Cisco big kudos for the clarity of explanation and visual representation given of co-channel interference in these 15 pages.  

Let's restate the problem for clarity:

Regardless of how much power you're using at the AP or client, transmissions will affect the RF environment around the device at a much greater range than the data transmission actually needs to go.

Cisco makes another statement within those same 15 pages that I very much agree with, "It is not an effective strategy to reduce the overlap in order to reduce co-channel interference.  As users satisfaction can be greatly affected by poor roaming performance.  In contrast, call capacity can be addressed in planning and design."

What they're saying here is that you can't spread the APs out far enough to mitigate this RF interference problem because you'll break roaming, which is true for most systems.  So what is this blog post all about?  It's about something totally different that needed this information as a pre-requisite. :)

 

Continue reading...

  • CWNP

Aruba copies Meru? You decide.

http://www.wi-fiplanet.com/news/article.php/3774851

If you haven't read the articles or gotten the countless press releases, Aruba just released ARM 2.0.  The more I read about ARM 2.0, the more it sounds like Meru...someone who's technology Aruba dedicated a 31-page whitepaper to dismissing earlier this year.  "Coordinated Channel Access", "Airtime Fairness", and "Performance Protection" are all concepts pioneered by Meru and absolutely TRASHED by Aruba in their whitepaper here:

http://www.arubanetworks.com/pdf/technology/whitepapers/wp_RFARCH.pdf

So now we trash the ideas and features of the competition publicly in long, detailed, inaccurate whitepapers - immediately followed by announcing the same ideas and features in our own company and products?   What the @!#$&^ ??  It's not like people aren't watching and listening already.

Continue reading...

  • CWNP

RF Barrier

As you may have already read in various online high-tech rags about Meru Networks' new offering: RF Barrier.  If not, here's a good one by Lisa Phifer: http://www.wi-fiplanet.com/news/article.php/3761666

What's missing from these articles is the technical details, which are nothing short of COOL!  For example, the RF Barrier APs listen on their "internal" antenna, read in the MAC header (analyzing the source and destination MAC addresses), and then make a decision on whether or not this traffic is part of the internal (authorized) network.  If it is, then it immediately begins transmission on its directional, externally-facing antenna to "talk over" the frame.  The AP typically transmits a data frame (that's essentially just saying, "hello") to corrupt the original transmission on the exterior side of the building.  By transmitting at the same time as the original transmission, additional airtime is not used.  That makes RF Barrier a very good neighbor.

 

Continue reading...

  • CWNP

802.11r - R is for 'Radar, not on the'

I'm shocked.  I've been pinging infrastructure manufacturers, VoWiFi manufacturers, client vendors, and anyone else who will eventually add a new form of standardized key management to their equipment.  Everyone says basically the same thing, 'It's on our roadmap, but not a big priority at this time.'  They all elude to the fact that they are either waiting on the Wi-Fi Alliance to finalize the Voice-Enterprise certification or they are waiting to see what other vendors are doing.

 

Continue reading...

Page 32 of 39