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Bring Out Yer Dead: 5 Steps to Eliminate 802.11b From Your Networks

Now that US tax day is over, we in the wireless field can get back to focusing on P1: optimizing and maintaining network performance. Keeping your network in good shape is like gardening: if you don’t pull out the weeds, it’ll never look as good as it could. My friend Jim Florwick detailed the gory bits of the 802.11b penalty with its awful lag in efficiency and absolute waste of spectrum. I write today to help give you the steps to act on Jim’s order to stop the madness.

I liken this process to a memorable scene from Monty Python: You must “Bring out yer dead.” However much the first standard insists it’s still alive, let’s all be honest with ourselves: 802.11b is dead.

In memoriam of the first amendment to the IEEE 802.11 wireless networking standard hailing all the way since 1999, 802.11b was superseded by 802.11a and g in 2003 which are much more efficient.  802.11n was available in draft form in 2007 and was ratified in 2009 while 802.11ac was ratified last September. A few years from now we should be planning the wake for 802.11a and 802.11g as well.

Now is the right time to bury 802.11b and reduce the drag on your network. Let’s be real: there is a reason cyclists are not allowed on the freeway, and an 802.11b device will slow everyone down. Here are 5 easy steps for eradicating your network of 802.11b and getting on your way towards higher speed wireless:

STEP    1.         Identify any 802.11b devices on your network

All of the latest Wi-Fi connecting devices are 802.11a/b/g/n capable. So how do you hunt down the 802.11b-only devices? You’ll be looking for older laptop and mobile clients (mostly before the year 2005).

Cisco Prime Infrastructure makes this easy for you with a report on clients by protocol. It will look like this:

prime1 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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HDX Blog Series #1: Why Spectrum Intelligence Still Matters

Editor’s Note: This is the first of a four-part deep dive series into High Density Experience (HDX), Cisco’s latest solution suite designed for high density environments and next-generation wireless technologies. For more on Cisco HDX, visit

CleanAir for 802.11ac:  Why Spectrum Intelligence Still Matters

In wireless networking and communications, as with life, nothing good comes for free. It’s well known that the primary feature of the new IEEE 802.11ac amendment is support for an 80 MHz-wide channel. The benefit of an 80 MHz channel is the potential to double usable throughput in comparison to that of 802.11n using a 40 MHz wide channel.

However, what is less well known is that a wider RF channel is also more susceptible to interference. In other words, 802.11ac devices “hear more” than 802.11n devices, primarily due to the wider channel support. It should be noted that this is not a flaw in the 802.11ac amendment, it’s simply basic communications theory.

Nevertheless, there is far more to building an 802.11ac access point than simply meeting the standard. Not all 802.11ac access points perform equally without interference. But more importantly, not all 802.11ac access points perform well in the presence of interference.

Furthermore, there is far more to deploying High Density wireless LANs than only considering the performance of individual access points. Read More »

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Prepare Your Networks for High Density without Compromising on Performance

A new year means new users and new devices. More devices means more network crowding. Mobile users demand bandwidth and speed, while the network is increasingly overwhelmed by the sheer number of devices. The networks of today and tomorrow have to be ready for high client density environments.

That’s why we’ve developed the Cisco High Density Experience (HDX). I announced HDX in a blog last October with a high level look at Cisco’s answer to handling high client density environments. Each feature in the HDX solution was designed specifically to alleviate the introduction of more clients, more bandwidth hungry applications to provide an unparalleled user experience.

Starting tomorrow we’ll kick off an HDX blog series to dive deep into the four key features that come with HDX:

  1. January 8: CleanAir
  2. January 13: Turbo Performance
  3. January 27: ClientLink 3.0
  4. February 10: Optimized Roaming

For more on Cisco’s approach to 802.11ac, visit


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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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