Blog

• CWNP
• December 14, 2009
• 

Fluke Competes with Cognio

I’m a fairly self-conscious writer.  There’s plenty of good writing on the web to capture our limited attention, so if you take the time to read these articles, let me start by saying we appreciate you!  A primary part of my job is to know as much as possible about the industry, including new features, products, standards, and vendor solutions.  In that interest, I spend a lot of time sifting through potential ideas for the blog and, hopefully, presenting valuable information here.  Back to my self-consciousness… I bring that up only because I never want to sound like a broken record around here.  However, I realize that I have a predilection for writing about laptop-based analysis products and free software, so here’s one more for the books that falls into the former category.  I’m convinced this one is noteworthy.

• CWNP
• December 10, 2009
• 

First Certification: 3x3:3

By now, you’re likely well informed about the 802.11n-associated lingo related to MIMO, but if you’re not, here’s a quick tutorial before I get to the point of the article.  When referring to 802.11n devices, companies often use an abbreviation that looks something like this: 2x2, 2x3, or 3x3 (pronounced 2-by-2, etc.).  These numbers refer to the number of transmit (Tx) and receive (Rx) radio chains, respectively, that are part of the MIMO hardware design.  The first number (the ‘2’ in 2x3, for example) is the number of transmit chains.  The second number (the ‘3’ in 2x3, for example), as you’ve probably already deduced, is the number of receive radio chains.  If you remember from 802.11a/b/g SISO systems, there is only one transceiver with one transmit and receive radio. 

• CWNP
• December 08, 2009
• 

Wireless Security Implications of 802.11n

I am sure that all of us have bumped into IEEE 802.11n at some point in time – it is the latest sensation in the 802.11 family of standards. It enhances the operative range of Wi-Fi devices and enables wire-speeds. It is no surprise that most (probably all) of the wireless LAN (WLAN) equipment vendors have announced support for 802.11n. Each vendor seems to be claiming that they have the “most conducive” architecture to avail the performance benefits of 802.11n. In this article, as usual, I would like to get your attention to another important aspect of an 802.11n deployment – security. While it doesn’t explicitly introduce new security features, 802.11n does introduce certain unique challenges to your enterprise wireless LAN (WLAN) security.  Here’s how:

• CWNP
• December 07, 2009
• 

Outsourcing 802.1X Authentication Services

I recently announced a new business, NoWiresSecurity. We provide a hosted service called AuthenticateMyWiFi™. This service makes it much easier for businesses to use the Enterprise mode of WPA or WPA2 (802.11i) encryption for their wireless networks.

In this post, we'll discuss why outsourced RADIUS/802.1X services are needed.

• CWNP
• November 30, 2009
• 

The Plane Truth

As I continue to study and learn about the nuances of WLANs, I’ve found that there are some conceptual frameworks that help in the organization of the unwieldy quantities of information.  If you’re at all like me and have a lot of disparate pieces of information floating around in your head, organization is massively helpful.  Understanding how a technology works is usually a minor undertaking as compared to understanding how a set of technologies work in cooperation.  That is often my struggle, so I am hoping to share—at a high-level—about a framework (and terminology) that helps to organize some of the processes related to WLAN functionality.  This organizational taxonomy breaks down the basic WLAN functions into three planes: management, control, and data.  Each of these planes includes a set of functions.    

• CWNP
• November 12, 2009
• 

Understanding OFDM- Part 4

In the previous episode of “Understanding OFDM”, we discussed the effects that convolutional coding error correction has on our overall channel data rates. The reason for using an error correction mechanism is to attempt to recover signaling information which has been corrupted by RF noise or interference during its transmission. But what exactly is this RF noise and how does it corrupt our OFDM-based 802.11 transmissions in the first place?

• CWNP
• November 06, 2009
• 

On Classroom Education

I had a bit of a work vacation two weeks ago.  I spent the week auditing a CWSP class with David Coleman (author of the CWNA study guide).  Unfortunately, taking a week to do something like this doesn’t mean that my other responsibilities magically disappear, so it made for a busy week and a long commute through the bottomless traffic pit that is Hotlanta.  No less, it was a great experience just sitting in the back, observing and participating in the structured and systematic 802.11 security education.

• CWNP
• October 30, 2009
• 

Vendors are Getting Saasy

Aruba started a competition that is beginning to get interesting.  Aerohive started a different competition that seems to be catching wind.  What am I talking about and who are the competitors?  Well, Aruba got down and dirty on AP price, so Aerohive got down and dirty on AP price.  Aerohive introduced a hosted WLAN management solution, so Aruba did the same.  Motorola (with Brocade) announced intentions of following suit, but we all know that big partnerships between big companies with big plans take big time.  I’ll leave it to you to decide who is leading the race, but here are the facts. 

• CWNP
• October 27, 2009
• 

Understanding OFDM - Part 3

In Part 2 of this series, we determined the maximum baud rate for 802.11a/g, and calculated the maximum channel data rates by modulation type.  As an example, if using a BPSK modulation type  we arrive at raw channel data rate of 12 Mbps, for an 802.11a/g channel.  As a wireless LAN professional, you may be aware that the lowest data rate offered, in a pure OFDM 802.11a/g network, is 6 Mbps.  In order to understand the difference between the raw channel rate and the actual available channel rate, we need to see the effect that the forward error correction (FEC) mechanism used with 802.11 OFDM technologies, has on the transmitted information stream.

• CWNP
• October 23, 2009
• 

Wireless LAN Security and IEEE 802.11w

As Wireless LANs (WLANs) have been increasingly entrusted to carry mission critical enterprise data and voice communication, the impact of Wireless LAN (WLAN) Denial of Service (DoS) attacks has increased manyfold. The recently ratified 802.11w standard that provides Management Frame Protection (MFP) does provide some help in fighting WLAN DoS attacks. But, if you think that 802.11w can put an end to all of your WLAN DoS problems, I beg to differ. Please read on to find out why.