Even with the best wireless gear, characterizing Wi-Fi performance is a pain in the buttocks and difficult at best.

Reflections, refractions, signal fading and attenuation all wreak havoc on throughput causing performance to vary freakishly.

Because wireless performance is inherently statistical, accurate performance testing must account for this random component.

Here's a good Black Paper on "Characterizing Wireless Performance" written by one of our super geeks (apologies in advance).download it here.

Ultimately, real-world wireless testing is essential, but this testing must be performed in a way that exposes the underlying performance statistics, looking beyond average throughput.

Sampling is the key to recovering the statistical performance and must be conducted across all relevant dimensions. Time-based sampling of the wireless channel, sampling at a large number of locations and sampling across the full range of channels are the keys to providing valid comparisons and predictions.

Introducing Zap: Now Free!

Zap is a wireless performance testing tool that Ruckus engineers developed precisely for this purpose. While Chariot and NetPerf are good tools for determining average (50%) throughput, they are expensive and don't do the best job in sampling to the 99.5 percentile.

Zap works by sending controlled bursts of packets and measuring both packet loss and inter-arrival times. The primary results reported are number of packets lost, total packets received and detailed throughput statistics. Because Zap provides a measure of both throughput and consistency over time and distance, it has particular importance to streaming video, voice and other latency-sensitive applications. Conversely, knowing only average throughput levels will not help predict the performance of a wireless network. By measuring the maximum throughput of batches of packets, Zap is able to determine the minimum throughput that can be expected at a given percentile

We initially developed Zap to as a way to figure out worst case performance for multicast IPTV streaming. Service providers just don't care about average throughput, they care about what they can guarantee - what they can charge for. For Ruckus, Zap has been invaluable making our Wi-Fi products perform better.  With it, we've been able to effectively guarantee how they will perform 99% of the time in a given area (just don't hold us to it).

Zap lets any company better understand the statistical throughput distribution of a wireless system to more accurately characterize Wi-Fi performance. With Zap, admins can easily test sustained throughput of an existing system and predict the real-life performance of a planned system before deployment.

By enabling an accurate determination of the true, sustained and worst-case performance that a wireless network can deliver 99.5 percent of the time, companies can become more confident in knowing that their wireless network will adequately support the more stringent application requirements that exist and the quality of service that users have come to expect.

Now in our infinite wisdom, we are releasing Zap to the world. We've released the raw code to open source and have posted compiled versions for the PC (download Zap_install_20091231) and the Mac (download Zap_mac_20100111) to anyone who wants to use it. 

NOTE: The ZapD file is a daemon that runs on the server, the other Zap file runs on the client.

By now you've probably heard that Meru is going public, having filed its S-1 with the SEC. 

Today, Aruba is really the only pure-play, publicly-held wireless LAN company. For better or worse (mostly for worse up to now as the market has under-valued the company bashing their stock in 2008), Aruba has become the ruler against which all others are measured with respect to valuation. So having Meru out there will be another good data point.  Or will it?

We'd LOVE to see Meru come out with a HUGE IPO. But this company is ill.

A closer look (if you can see it...sorry it's so small) at their balance sheet (click on graphic, left) shows a company that has struggled, having raised a boatload of capital ($126M in equity plus $27M more in debt).  Over the past year, Meru's invoiced product and services has largely remained flat. Invoiced product and services for the 9 months ended Sept. 30, 2009, were $41.2M versus the 9 months ended Sept. 30, 2008 which were $40.5M.

Apparently from Meru's S-1, Series E holders have a ticking time bomb on their hands.

<SNIP>

"In the event that we have not completed an initial public offering of our common stock or a reverse merger into a public company by March 31, 2010, we would be required to pay $0.6 million to a holder of our Series E convertible preferred stock. If we still have not completed an initial public offering of our common stock or reverse merger into a public company by April 15, 2010, we would be required to pay an additional $0.6 million, and an additional $0.2 million would be due each month beginning April 30, 2010 until the completion of an initial public offering of our common stock or reverse merger into a public company."

<SNIP>

And while their "big MAC" (single channel blanket) architecture is technically notable, it is highly complex, expensive and riddled with issues. Given that all the APs on a "blanket"  share the same channel, coping with interference or environmental changes that cause performance fluctuations is effectively impossible. Throughput is also limited though Meru claims they can have three discrete blankets (on channels 1,6,& 11) in the 2.4GHz band. According to former employees, more often than not, their single channel blanket architecture is not even implemented due to the inability to get it to work properly and stay working properly.

All that said, to go public in today's economy, you need three quarters of consistent profit, visibility in future revenues, a demonstrable differentiation and diversification across products, customers, markets and geographies. The problem is, Meru has none of this.

And finally, the company has really struggled to retain key staff and senior execs. 

• Bob Bruce former VP of channel sales. Gone.
  
• Dan Steimle, former chief financial officer. Gone.
• Steve Troyer, former VP of product marketing.  Gone. 
• Fred Corsentino, former VP of sales. Gone. 
• Anil Batria, former VP of international Sales. Gone.
• Michael Tenefoss, former VP of marketing. Gone.
• Keith Matasci, former VP of operations. Gone.
• Tushar Kothari, former SVP of field operations. Gone.

It's a soap opera. The bottom line is that these are not signs of a stable company. 

But still, we're still crossing our fingers, legs, toes and every other appendage we have at our disposal in the hopes Meru can pull this off.  Ultimately, these are some very smart people.

Those in the know, know about QR codes.

Created in the mid-90s by a Japanese company called Denso Wave, QR codes are are two-dimensional bar codes that can contain any alphanumeric text and often feature URLs that direct users to sites where they can learn about an object or place (a practice known as “mobile tagging”). 

The mesmerizing would-be Meru board-member on the right has a QR code that will take you to the Ruckus Wireless Web site. 

Here's a good one-pager on "7 Things You Should Know About QR Codes."

Decoding software on tools such as camera phones interprets the codes (here's a free QR reader for the iPhone), which represent considerably more information than a one-dimensional code of similar size (QR codes can encode up to 2K bytes of data).

The codes are increasingly found in places such as product labels, billboards, and buildings, inviting passers-by to pull out their mobile phones and uncover the encoded information.Tracking information for products in industry, routing data on a mailing label, or contact information on a business card.

Small in size, QR code pattern can be hidden or integrated into an esthetically attractive image in newspapers, magazines, or clothing. Simple QR code generators are online to help people make these things.

Users with a camera phonesoftware  can scan the image of the QR Code causing the phone's browser to launch and redirect to the programmed URL.

Think about it. The combination of mobile phones equipped with a built-in phone, embedded Wi-Fi and a QR code reader (here's another free code reader for Blackberries), pretty much eliminate the hassle for users to get where ever you want them to go on the Internet.

Mobile operators are extremely interested in solving the single signon issue. Single sign on is the idea where a user needs only log-in once to any service provider's network. Once the users roams to another location or another network, they don't need to login again because the network keeps track of who the users is and all their authentication credentials. There's a ton more to it, but that's the basic concept.

QR codes could come in REALLY handy for helping mobile operators and telecom companies that want to provide easy sign-on.

Mobile operators could leverage built-in smartphone QR-to-URL software and generate QR codes that automatically takes users to a pre-coded URL for login in or authentication - eliminating the hassle of having to give out URLs that are mistyped, etc.

Despite our incessant spewage about smart antenna arrays, dynamic beamforming and maximal ratio combining, there's more to Wi-Fi and networking than RF (but don't ever say this to our founders).  There's security, user roles and access policy and a load of other fancy techniques usually associated with island vendors. 

We talk to a lot of hotels, schools, hospitals, warehouses and other types of enterprises who want sophisticated Wi-Fi/network management but want it radically simplified. User identify or so-called "identity management" is one of those things.

How can you know if  users are who they say they are on your network?  Here are some simple ways to manage user identity in a more simplified fashion (we're Wi-Fi simpletons):

Of course there are some other, less common, techniques available but this is a reasonably representative list. Each method has its own advantages and disadvantages. So which one should you use?  Our motto: when it doubt, keep it simple.  You'll be happier.

Lots of people thought 802.11n would kill us. But it's done the opposite.

In our last two quarters, 802.11n "smart" APs have accounted for 52% of all APs we've shipped (and we shipped nearly 150,000 this quarter).

These same people have been surprised that our fancy-ass (that's what we call it) beamforming technology works extraordinarily well on top of 802.11n. 

Before the company even started, our two founding fathers (though one of them has yet to breed) got a lot of questions that hinted at the belief that "MIMO chipsets" and multi-radio techniques such as spatial multiplexing would eventually put a silicon dagger through the heart of our innovative, adaptive, state-of-the-art, revolutionary, breakthrough, one-of-kind (this is the paragraph our marketing people wrote) smart antenna array that we talk so much about. 

Bill and Victor (as they are known) simply smiled and tried to explain the big gains and interference rejection properties that smart antennas could provide on top of ANY wireless system - regardless of the number of radio chains. They (VC's usually) would smile too but still suspected in their semiconductor-schooled heads that we might go the way of the math-coprocessor. 

Fortunately, half of us came from the network school where we had learned to appreciate the immediate competitive advantage conferred by simply throwing bandwidth at a problem. The other half, RF-schooled, understood how precious and hard to come by were those extra antenna dB's. We knew that our technology had long legs, and quite sexy ones at that.

Fast forward five years later to 2008. The most trendsetting of our IPTV customers start making the upgrade from standard definition to high definition. For that they needed 802.11n. And for the first time we found ourselves with actual "competition" in the form of video dongles sporting off-the-shelf 802.11n silicon. 

But what a joke those turned out to be. If it had been a boxing match the referee would have declared a technical knockout (TKO...get it?). 

Here is an example of the performance disparity seen between Ruckus 802.11n systems and other 802.11n systems. In this case the "competition" is a Netgear 802.11n system with a really nice Atheros chipset similar to the one we use. This product actually has an internal antenna array designed apparently by Rayspan, so the comparison is particularly enlightening. 

This graph (click on it) shows the probability of getting a particular minimum throughput if the client is placed at a random location in a typical home. 

Yikes! These guys better hope the referee shows up soon - they are wobbling. 

Contrary to VC wisdom, 802.11n is driving our explosive growth. This is because signal path control and interference mitigation become even MORE important. We'll cover the reasons for all this some other time (hint: more radios means MORE ANTENNAS....go figure).  Until that time, don't believe everything you read...or hear.  Believe what people are paying money for and actually using.

If you ever have the chance to meet our CEO, Selina Lo, don't look her in the eyes, look her in the feet. 

She's the proud owner of hundreds of pairs of shoes that are quietly kept in their own living space. That's right.  People think it's just something we conjured up to make her sound eccentric.  It's not. 

So when I recently got access to her house, I thought I'd document it for all to see.  The video doesn't really do this justice but will give you some idea of the depth and breadth of this fetish.

She goes on shoe binges whenever she's in Milan, Hong Kong, or well, let's be honest, anywhere. I've had first-hand experience of one of these binges before - watching her drop thousands of dollars like a drunken sailor on two or three pairs of shoes in about 10 minutes.

She typically has two or three shoe salesmen running around Lane Crawford, Nordstrom's or Jimmy Choo's, getting her this and that  Her favorite shoes are the skull and crossbone boots pictured in the video.  What a surprise.

All her shoes are kept in a custom room with layers of  floor-to-ceiling shoes shelves on rollers. Behind the shelves are MORE shoes, handbags, scarves, etc.  It's a walk-in shoe closet essentially. Can you say ISSUES? (she had just bought a new pair of tennis shoes that day to play tennis in).

Ever heard one vendor praising a competitor in public?  Well, here it comes.

Not only did Aerohive recently give us a great a new CFO but they recently announced a very familiar (and well-loved) wireless security feature they called “Private PSK.”

It's almost identical (but not) to our own Dynamic PSK (so we were very flattered). But they've added some very cool knobs.

Like our Dynamic PSK technology, Private PSK fills a gap between WPA-PSK (pre shared key) technology and WPA enterprise mode (802.1X).

You’re probably familiar with WPA-PSK already, practically every consumer-grade wireless AP lets you setup WPA-PSK encryption where you define a key on the AP. Any wireless device that tries to connect to that network will need to type in the same key to connect. This technology has been widely implemented because it is easy to deploy and understand.

While WPA-PSK works fine in a small environment, when you have multiple people sharing the same key, in a company for example, you start to have problems keeping the key a secret. What's more, if the key is ever compromised, the only way to re-secure your network is to change the key on the AP (easy enough). But then you’ll have to update the key on every client device manually (major suckage).

WPA Enterprise (another way to really say 802.1X) solves this problem by requiring that clients authenticate against a RADIUS server first before they are allowed onto the network. Every user has a different username and password on the RADIUS server somewhere. So if a user needs to be revoked, the administrator can delete their entry. All of the other users would remain unaffected by the change.

In the real world, this can be exceedingly complex to deploy and manage. Many companies don’t have RADIUS servers, so one will have to be setup and maintained. Furthermore, the setup on the client side is very complex. Instead of typing in a single key like you would with a WPA-PSK secured network, multiple configuration adjustments need to be made (eg. the client computer must also have a certificate installed that is used to check against the certificate listed in the server).

In a typical 802.1X configuration this can easily add up to ten separate steps. This frustrates users and puts an increased burden on systems administrators who will need to assist each user in configuring their device. And devices that don't support WPA Enterprise remain unsecured with this approach.

Our Dynamic PSK (as well as Aerohive’s Private PSK) takes the "best of both worlds" approach to solve this security dilemma. See fairly fair comparison chart.

Administrators can choose to enable Dynamic PSK and have the system automatically generate a unique key for each user. Our approach actually downloads and installs the PSK automatically on the client along with the requisite SSID - and we bind the Dynamic PSK to the MAC address of a given device.

Aerohive's lets you manually generate keys or groups of keys that can be emailed and there's no need to login - but users still must install the key (also note that Aerohive's Private PSK requires the HiveManager appliance and the Guest Manager application to fully function which is kinda weird given their religious bent toward a "controller-less architecture"...but whatever we have our own problems).

Each user can then use their own unique key to connect to the wireless network, just like a traditional WPA-PSK network.This is especially convenient for devices without a WebUI. If a key is compromised, administrators can choose to selectively revoke that single key and generate a new one to replace it.

All other keys remain valid, so other users do not need to take any action in this case. Another advantage of this approach is on devices (such as mobile phones) where WPA Enterprise security is either very complex to setup or missing entirely. With AeroHive's implementation, a Private PSK can be used on multiple devices at the same time and each of these devices is shown as a different session when looking at their HiveManager management system.

With these new approaches users just need only enter their unique key into the device and they are ready to go.

But with Aerohive's Private PSK, administrators can choose to go a step further. They can assign user-based policies based on their key. In this way, different users, even if they are connecting to the same SSID, can have different VLAN, QoS or firewall settings depending on what key they use to login. That’s cool.  

So whether it’s theirs or ours, ultimately the simplicity that these technologies bring to wireless LAN security is truly game changing. Administrators will be able to maintain user-level control of encryption keys without the cost and complexity of deploying a full 802.1x RADIUS authentication system.