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Not All 802.11ac AP’s are Created Equal: Demand the Full Story

It’s always interesting and often entertaining to observe how competitors promote their products and what they choose to focus on—and more importantly, what they choose not to focus on and what they hope people won’t ask questions about.

Consider yet again how a competitor chooses to position their “purpose built” AP vs. the Cisco Aironet 3700 802.11ac Access Point Series.

This competitor frequently (and somewhat obsessively) points out that its 802.11ac AP has dual “active” 800 MHz cores while the Cisco AP3700 has only one “active” 800 MHz core. This is not completely true since it completely overlooks the fact that the Cisco AP3700 also has a dedicated CPU core and DSP for each radio subsystem.

Furthermore, it also overlooks that the dual “active” cores in the competitor’s AP share 512 MB of DRAM. The single “active” core of the AP3700 has dedicated 512 MB of DRAM. Also each radio subsystem has a dedicated 128 MB DRAM (for 768 MB total DRAM in the AP3700).


Why is all of this important? Read More »

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Winning Back the Weather Radio Channels Adds Capacity to 5GHz Wi-Fi Spectrum

In my last blog on 5 GHz spectrum, I discussed the recent FCC ruling that permitted outdoor access points to use the U-NII 1 band (5150-5250 MHz).

But the story doesn’t  stop there. As mentioned last time, there are significant technical challenges to using the 5 GHz band. It is not cleared spectrum. It contains incumbent uses that are important for national security and public safety. Therefore, it is imperative that Wi-Fi not create harmful interference to these incumbent systems. Cisco will not settle for less.

On the topic of interference, a particularly interesting component of the same  FCC ruling that opened the U-NII1 band for outdoor AP’s is that it also re-opened the Terminal Doppler Weather Radar (TDWR) band (channels 120, 124, 128) with new test requirements for DFS protection. Hold on, let’s backtrack a bit before diving into what this means:

What is TDWR?

In brief, Terminal Doppler Weather Radar (TDWR) “is a Doppler weather radar system used primarily for the detection of hazardous wind shear conditions, precipitation, and winds aloft on and near major airports situated in climates with great exposure to thunderstorms in the United States.” TDWR uses the frequency band from 5600-5650 MHz which is why wireless network equipment needs to be proven to “do no harm” to TDWR. If you’re curious for more information on TDWR, then please click here and/or here.

A Brief History

Many of you reading this will recall that the FCC closed the use of the TDWR band several years ago as the result of numerous reports of wireless equipment creating interference with TDWR. Read More »

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Score for IT this World Cup

Unless you’ve been living under a rock for the last two weeks, you know that the FIFA World Cup is in full swing. Stakes are higher than ever as we move into the semi-finals with more and more people tuning in to cheer on their favorite futbol teams. In fact, FIFA just released a media release yesterday about how this year’s 2014 FIFA World Cup™ has set new records for streaming data traffic around the world. My colleague Ido blogged about IWAN helping with the bandwidth overload caused by the FIFA World Cup last week, so let’s dive deeper and talk about video and high density.

There is no denying it: your employees and customers are streaming video. While the volume of that streaming dramatically peaks around game times during the World Cup, it should be no surprise that today, mobile applications, largely video, are increasing mobile traffic across networks. That’s straight forward: apps + video = bandwidth drain. Combine that with the fact that people are touting multiple devices--think a laptop and a smartphone, maybe a tablet, too. This means high density--lots of clients and devices on a single network. These circumstances trigger three potential yellow cards to cross an IT person’s mind – let’s see how we can avoid them.

YELLOW CARD #1: Rich Media Optimization

As an end-user, the common expectation is that I should get the same crisp, clear, rich  media or video experience across all platforms—I don’t care if it’s my phone, my tablet or my laptop: make it high definition. This is harder said than done.

It is not easy to provide the same rich media experience across wired and wireless devices. Traffic from wireless devices has to travel all the way back to the controller in a data center and then back to an access switch before reaching its destination. It’s called the hairpin effect. The result is that video over Wi-Fi could look grainy. That won’t do for the current generation of high definition junkies. Read More »

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The Momentum of 802.11ac Moves into the Real World

Wireless is enabling change everywhere. According to Cisco’s VNI Global Forecast, wireless traffic will bypass wired traffic 40% by the year 2017. This is evident by the way many organizations are using Wi-Fi technology.  Take healthcare providers as an example: many hospitals today rely on Wi-Fi to provide seamless clinician roaming, improved efficiency and patient care--not to mention patients’ relatives and friends who expect to connect to guest Wi-Fi. And then there is education where we are seeing both universities and K-12 schools faced with more and more students coming onto campus carrying mobile devices with bandwidth intensive applications like video.

The explosion of high performance applications and the number of clients using them is a big reason why 802.11ac adoption is happening at a rapid pace. 802.11ac as a standard addresses the performance needs of applications while providing a robust network that handles a growing number of client devices. Cisco provides our customers with a unique solution to meet the high density requirements with a technology suite called Cisco High Density Experience (HDX). HDX helps Cisco customers prepare beyond 802.11ac and addresses the key aspects of any network that is challenged by the high density of large numbers of clients on the network and increasing performance demands of bandwidth intensive applications.  Deploying 802.11ac with Cisco’s HDX Technology will provide a relief from the bandwidth demands while also making the overall Wi-Fi network more efficient.

With this in mind, we are hosting a webinar on June 26th where we focus on 802.11ac Standard, Cisco’s 802.11ac solution including our HDX Technology and how it can be used in various networks. We have also invite Joe Christoffersen who is the Director of IT at Katy Independent School District in Katy, TX to provide his unique perspective on how Katy ISD is deploying 802.11ac, how it will affect the performance of his network and the benefits he expects from this technology.

The webinar is next Wednesday at 1:00PM PDT. Here is the registration link. If you miss it, we will have it available on demand here shortly after.

For more on Cisco’s 802.11ac, visit

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The Network After 25 Years of Cisco Live!

#clus1A lot can change in 25 years. At the first Cisco Live (then known as Networkers conferences) in 1989, 200 geeks gathered for the inaugural event. Fast forward to three weeks ago, when we welcomed a whopping 25,000 attendees into the arms of our namesake, beautiful San Francisco.

We heard there was some interest in how the network performed at the show, so I wanted to share some of the interesting statistics about the network at Cisco Live! I shudder at the thought of the ancient network from 25 years ago. So here we go:

Wi-Fi Client Devices

This year we saw 30,705 unique devices, with 7000 in the theater for John Chambers’ keynote.

# of Unique Clients

# of Sessions

# of Unique Users

# of Unique APs

Avg Users per AP






Max. Concurrent Connected Wi-Fi Devices

There was a peak of 14216 concurrently connected device at SF this year.

clients2 Read More »

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