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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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802.11ac: That’s the Answer. What’s the question?

Everybody’s talking about 802.11ac, but we’ve sensed some confusion for next steps as far as how CIO’s and IT organizations should be approaching the new standard.

3700internal2Should I move to 802.11ac?

You’re probably thinking: Chris, you’re a leader at Cisco, of course you want me to migrate to 802.11ac. That, my friends, is where you are wrong. There is no simple answer to the question of whether you should move your network to 802.11ac. Here’s my simple rule of thumb:

There is no premium for 802.11ac from Cisco. If you are deploying new Access Points’s today, you should be buying 802.11ac. If you’re not buying, you are probably satisfied with your network and how it will handle the growth of more and more clients associating with your network and the bandwidth demands that come with that client demand. If you feel you have a plan to handle this demand, then you are one of the few that can pass on 802.11ac.

That said, there is a strong ramp up for Cisco 802.11ac products in the market, the AP3700 is the fastest ramping access point in our history and we have yet to see if the AP2700 will claim that crown in the coming months. ABI Research estimates that currently 50% of new device introductions are 802.11ac enabled, a statistic expected to increase to 75% by the end of 2015.  This is enough proof of the overwhelming interest in adding the benefits of 11ac to networks. Let’s take a step back and consider the basics of why people are moving to the new standard.

Why .11ac?

Today, everything is about getting what we want, when we want it. Instant gratification. It’s not just the millennials—we’ve all been conditioned to expect things within seconds. Could you imagine the days pre-Internet if you had the capability for on-demand movies? Read More »

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What, Why, Where, When, How: The New FCC Ruling Around 5 GHz

You don’t need me to tell you to know that we are in the midst of a technology revolution.  It’s mobilizing the internet.  And it’s transforming the way billions of people around the globe collaborate, communicate, and connect to the internet.

•           The education customers I work with are incorporating video and mobile applications into their curriculum with up to a 100 students in an auditorium accessing the Wi-Fi network simultaneously.

•           Healthcare customers are relying on Wi-Fi to connect patients, devices and provide nurses instant access to medical records.

•           Manufacturing customers are increasingly using Wi-Fi to enable workers on the factory floor to have real-time video conversations with experts anywhere in the globe.

What do these things have in common?  They all depend on Wi-Fi for connectivity.  In these areas, and so many more, Wi-Fi has become a central way that people access the Internet.

The FCC released a historic decision on April 1, 2014 (adopted March 31)with regards to the use of 5 GHz spectrum. Although there were many technical aspects included within this decision, one of the most interesting was making the 5150-5250 MHz U-NII 1 band available for outdoor WLAN use. Read More »

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All 802.11ac Vendors are the same…Right?

If you are an Enterprise IT Manager, this is a question that you must ask yourself if you are considering deploying 802.11ac for your enterprise wireless network. 802.11ac has some great benefits such as wirelike speed and being able to handle a high concentration of clients. However, there is more to consider when deploying 802.11ac. For instance, how do I handle RF interference now that 802.11ac support 80MHz channels? Will legacy devices such as 802.11g/a/n allow me to achieve the best performance that 802.11ac advertises? How can I ensure that my users get the best wireless performance when they roam across a building? And lastly, as more clients join the network, is my performance going to suffer? These are all valid concerns and are something that Cisco addresses with HDX. HDX is High Density Experience and is part of Cisco’s 802.11ac solution. We just wrapped up a 4 part blog series on HDX where we answer these questions:

-          For Interference Mitigation, we have CleanAir for 80MHz Channels

-          Getting the best performance out of your network even with legacy clients, we  have ClientLink 3.0 Read More »

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Miercom: Cisco Aironet AP3702i

Cisco’s newest 802.11ac product, the Aironet 3700 Series Access Point is now orderable and shipping in the next few weeks.  The AP 3700 features an integrated 11ac radio with a 4x4 architecture and Cisco’s High-Density Experience (HDX) Technology.  HDX is a suite of features specific to the AP 3700 that delivers the best possible user experience, especially in high client density networks.  HDX is enabled by a combination of  hardware and software features on the AP 3700, features including:

  • CleanAir 80 MHz – Interference detection and mitigation
  • ClientLink 3.0 – RF link quality
  • Smart Roam – Intelligent roaming handoff
  • Turbo Performance – Performance with high client density

Aruba recently launched their 802.11ac access point, the AP-220 series, featuring a 3x3 design.

Miercom recently published a third-party evaluation of the performance between the AP 3702i and the AP-225.  The report consists of a diverse range of test cases meant to gauge real-world performance of the access points.  The tests include; multi-client performance, single client rate vs. range, performance in the presence of interference, and performance on reduced power.  Here are some of the highlights from the report.

Multi-Client Performance

The AP 3700 performed very well in the multi-client performance test, thanks impart to HDX Turbo Performance.  With 60 clients, the AP 3702i had a 6x performance advantage over the AP-225.  The AP-225 struggled to serve all the clients and only mustered 40 Mbps total.  The AP 3702i was able to transmit a healthy 236 Mbps, while maintaining fair throughput to each client.

The test consisted of 60 11ac clients, all associated to the 5 GHz radio.  The clients used were 10 Dell E6430 laptops with Broadcom 4360 three spatial-stream chips, 20 Apple Macbook Air two spatial-stream laptops, and 30 Dell E6430 laptops with Intel 7260 two spatial-stream chips.  Clients were setup in an open office environment surrounding the AP.  Distances varied from 10’ to 50’.

1-Mulit-Client Read More »

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