Category Archives: 802.11ac

WiFi for Chicks & Jocks…



WiFi for Dummies sounded too cliche and I suspect is a registered trademark, so I am going with WIFI for CHICKS & JOCKS.  This topic reminds me of when my old friend and former governor of California called WiFi Superman asking for help understanding WiFi.  He explained that although he had played superheroes, he was not actually a superhero nor was he extremely technical.  So I will try to recreate the primer I shared with him, this will teach you the basics.

WiFi is a technology that uses radio-frequency waves (electro-magnetic energy) that allows devices to communicate.  The standards that WiFi adheres to were developed by the IEEE under 802.11 (there are numerous amendments).  Two other bodies exist to regulate and provide interoperability for you and your WiFi devices.

The FCC regulates which frequencies you can “talk” on and how many watts are allowed.  The WiFi Alliance certifies devices by testing the functionality of devices to make sure that they comply with 802.11 standards and the amendments that add features and functionality.  The FCC is responsible for fining Marriott Hotels for jamming non-hotel signals as WiFi operates in an unlicensed frequency band and therefore anyone can transmit or receive on those bands.  The WiFi Alliance is responsible for making sure that your Dell laptop’s WiFi card can secure and communicate with  your Linksys wireless router.

WiFi exists in the 2.4 GHz (ISM band) and 5.0 GHz (U-NII) bands.  Not all cards support both.  802.11 started with data rates of 1 and 2 Mbps.  After amendments a,b,g,n,and ac we are looking at data rates in the Gbps range.  802.11n and 802.11ac have included many enhancement such as MIMO (multiple-input and multiple-outputand beamforming that make these high-throughput (HT) data rates possible.  Now might be a good time to get a cup of coffee if your brain is exploding or if you have had enough.


Okay apparently you want to know more.  So what is an Ad-Hoc network?  Essentially an Ad-Hoc network is a wireless network that does not use an Access Point as the central point of communication.  In an Ad-Hoc WLAN one device acts as the central coordinator (like a cell-phone Mi-Fi).  Having your device set to deny ad-hoc connections is a good security practice otherwise it is easy to be compromised by someone.  Other good practices are to avoid Open SSIDs as they do not use encryption and leave you vulnerable to eavesdropping.

“warchalking”           symbol for an             open SSID

So when setting up your home WiFi always use the strongest encryption.  Choose WPA2 over WPA,  AES over TKIP, and never use WEP: an easy WEP passphrase can be broken in seconds.  If you have advanced hardware and some time and patience you may be able to set up 802.1x/EAP as opposed to just PSK.  This also increases your security,  using 802.1x/EAP will prompt a mobile device for username and password.  The keys used by the AP when you use this method are more complex and change more often, they are therefore superior.

I remember Arnold had a specific question for me.  He asked, why is it that my wireless is always set to CHANNEL 6?”  I explained to the Governator that there are 14 channels in the ISM band, however one can only use 1 through 11 in North America.  Out of these 11 channels there are 3 that do not overlap.  They are 1, 6, and 11.  For some reason manufacturers almost always default to channel 6.


I think that is enough for the first WIFI for CHICKS & JOCKS.  If you have specific questions you can leave me a message and I will reply on this blog.

RF hero MIMO converts multipath to good


By now you have probably heard about 802.11ac which boasts data rates up to 1.3 Gbps.  If you haven’t I imagine you know about 802.11n.  So what makes these IEEE standards so good?  Well for one thing the “N” standard introduced Multiple Input/Multiple Output or MIMO.  Now hold that thought for a moment…

Back in the days prior to 2009 we had this ugly problem called Multipath.  To an RF signal there are many forces of evil working against successful transmission.  Reflection (RF Energy bounces off a smooth surface predictably), Diffraction (waves bend around sharp objects), and Scattering (RF Energy reflecting off the texture of a varied surface like stucco);  these are just some of the nefarious foes RF faces daily. Multipath is how RF energy waves react when parts of the wireless transmission meet at the antenna with differences in time and geometry.  Back in the beginning of the millennium multipath was a problem that was addressed by using antenna diversity.

If there was really a superhero called MIMO it would be Dr. Greg Raleigh.  The Qualcomm innovator was responsible for the development of MIMO which Qualcomm defines as follows: “MIMO systems divide a data stream into multiple unique streams to take advantage of multipath signal reflections to actually improve radio transmission performance.”  So when MIMO combines with other enhancements like TXBF, STBC, and SGI we see data rates really sky rocket.  To find out more about 802.11n and 802.11ac follow the links below.










ARUBA NETWORKS 270 Series Outdoor Access Points


Posted originally on July 7, 2014 By: John Busso, CISSP, ACMP, ITIL

Aruba AP270 Highlights

  • 802.11ac in 5.0 GHz band with up to 1.3 Gbps data rate
  • 802.11n   in 2.4 GHz band with up to 600 Mbps data rate
  • AP275 has an integrated MIMO Omnidirectional antennas
  • AP274 allows for external MIMO N-type antennas
  • Aesthetic design mimics common fixture for lighting/cameras
  • NEMA and IP-rated (IP66/67) for harsh environments
  • ClientMatch enabled to leverage 802.11k,r,and v standards
  • Flexibility for use as campus, remote or independent AP
  • 48VDC 802.3at-compliant or  100-240-Volt AC Power

I have been designing and implementing wireless networks since the ratification of 802.11 (yes prior to 802.11a or b).  I have seen many technologies come and go, such as WiFi using 900 MHz and Free Space Optics (FSO), which was essentially wireless using lasers as opposed to microwaves.  Aruba gets it right again improving on their existing outdoor wireless access point (see full product line here).  The AP270 series outdoor access point is a purpose-built, state-of-the-art device that will survive extreme conditions and anticipated wireless standards, making it “future-proof” for years to come.

To understand what makes the AP270 such a great WiFi access point we need to look at a few key factors: being future-proof, easy install and manage, flexible, and high-performing.

  • AP270 access points are future-proof because they are fortified against extreme weather and environmental contaminants.  The AP270 can operate between -40° F and  150° F.  It withstands humidity in a range of 5%-95%.  The access point can withstand up to 165 mph winds.  The Aruba 270 series AP is also future-proof because it uses the latest IEEE specification 802.11ac .
  • This outdoor access point is easy to install with only two mounting template one for wall-mounting and one for pole-mounting.  The mounting kits come in long and short depending on your specific application. Ethernet and serial console access makes configuring the AP270 easy and flexible.  The AP275 comes with integrated internal 3×3 MIMO antennas.  The AP274 can utilize any N-type antennas needed for your application .
  • Managing Aruba APs is easy and flexible because one can use the virtual controller resident on iAPs, controllers for campus and remote APs, or AirWave network management system for all of the above.
  • Aruba’s AP274/275 Access Points are high performing 802.11ac Access points that leverage several technologies.  Transmit Beam Forming is used for increased reliability in signal delivery.  Low Density Parity Check allows for high-efficiency error correction and increased throughput.  Maximal Rate Combining improves receiver performance.  Advanced Cellular Coexistence is employed to minimize interference from cellular systems.  To improve downlink RF performance the AP270 uses Cyclic Delay Diversity.

So to sum it up, Aruba’s AP274’s and AP275’s are good looking, easy to install, flexible, and high-performing.  Remember that they can be used as APs, iAPs or RAPs.  You can use the turnkey AP275 with its integrated antennas or select the AP274 when antenna tuning is desired.  Aruba offers all this at a list price of$1595 USD for the AP274.  For more information Click Here


WiFi Superman’s alter ego

Why do you need 802.11ac?

me                 REASONS YOU NEED 802.11AC

Originally posted 14 February, 2014

More, more, more

  • There are more devices which cries for efficiency
  • There are more applications which demands higher performance
  • There is more multimedia which necessitates getting users off and on quicker

Better coverage

  • Thanks to explicit transmit beam forming  your coverage is much more effective

Backwards compatibility

  • 802.11ac is backwards compatible for all other IEEE 802.11 standards
  • Even older chipset will benefit from many of the enhancements of 802.11ac


  • If you do not have 802.11ac then you will not have any visibility into emerging 802.11ac threats
  • Even if you are not ready to rip and replace your legacy system you could benefit by adding some 802.11ac APs as monitors.

To read more on this topic go here: