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Cisco Wireless Compatibility Matrix (Nov. 2011)

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My80211 Videos

Cisco: 802 11 frames with Cisco VIP George Stefanick

Fluke Networks: Minimize Wi Fi Network Downtime

Aruba: Packets never lie: An in-depth overview of 802.11 frames

ATM15 Ten Talk “Wifi drivers and devices”

Houston Methodist Innovates with Wireless Technology

Bruce Frederick Antennas (1/2)


Bruce Frederick dB,dBi,dBd (2/2)

Cisco AP Group Nugget

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Revolution WiFi Capacity Planner

Anchor / Office Extends Ports


Peek Inside Cisco's Gear

See inside Cisco's latest wireless gear!

2.4 GHz Channel Overlap




  • CWSP Certified Wireless Security Professional Official Study Guide: Exam PW0-204
    CWSP Certified Wireless Security Professional Official Study Guide: Exam PW0-204
    by David D. Coleman, David A. Westcott, Bryan E. Harkins, Shawn M. Jackman

    Shawn Jackman (Jack) CWNE#54 is a personal friend and has been a mentor to me for many years.  I've had the pleasure and opportunity to work with Jack for 4 years. Jack is a great teacher who takes complex 802.11 standards and breaks them down so almost anyone can understand the concept at hand. I'm excited for you brother. Great job and job well done! Put another notch in the belt!

IEEE 802.11a/g/n Reference Sheet


LWAPP QoS Packet Tagging



Interference Types


Microwave Oven

Cordless Phone



How to upload the running AP IOS image to a TFTP Server

Special Guest Post By: Steven Rodriguez
Since Cisco is locking down software downloads, you may have a need to pull code off your existing access points. Here is a quick recap showing how to process the code with the archive command!

Ever lost the code you were running on an AP?  Then need to load that code to another?  What if that codes not available for download from CCO anymore?  Well, there's a pretty easy process to get through to get the image from an AP, and onto your TFTP server.

In this example, I am using a 1131, running 12.4(21a)JY

The first thing you need, is a TFTP server.  There are plenty of free ones out there.  I tested this with TFTPd32 on a PC, and with TFTPServer on a Mac(10.6).

So on the PC, it's pretty easy.  Configure your TFTP Server

Once you've stopped then started the server, you simply need to issue the command

archive upload-sw tftp://

As this command is running, it extracts the current running IOS, including the HTML files, and tar them as it's sending to the TFTP server.  <Term mon if you want to watch the process run.>

On the Mac, I found it to be a little bit different.  With my Mac, even though I did a chmod 777 on my tftp directory, I had to do the following before I attempted to upload the software.

Once the file is 'created' in my target directory it becomes the same as the PC version.

archive upload-sw tftp://

Now, if you have multiple versions of code that have been extracted to your AP, there is a switch that can be used, /version

archive upload-sw /version c1130-k9w7-mx.124-21a.JY tftp://
                                                 ^this would be the version you wanted to upload.


Understanding Cisco Access Point IOS Images

From Aaron Leonard - Cisco

All Cisco Aironet wireless access points and bridges currently being shipped run IOS.  The only exception is the OEAP602.  (Some older Cisco access points did not run IOS, such as the Aironet 340 which ran only VxWorks, and the 1000 series lightweight APs.)

Access Point IOS is distributed as a tar file.  These tar files can be downloaded from SDS; lightweight IOS images (k9w8) are also bundled in the WLC software images (.aes.)

The IOS image names include the following components:


  • platform- the access point hardware model or family supported by the image       
    • examples: c1250; ap3g1 - 3500/1260; ap801- AP embedded in 881W; c1520 - 1520/1550
  • featureset- the set of software features supported by the image - one of:      
    • k9w7 - autonomous IOS
    • k9w8 - full lightweight IOS (this is what is bundled in the WLC .aes image, and is factory installed on "mesh" APs)
    • rcvk9w8 - lightweight recovery image - this is factory installed on lightweight APs, unless a "mesh" image is specified; it lacks radio firmware
  • version- the IOS version       


Example: c1240-k9w7-tar.124-25d.JA1.tar

  • Platform: c1240: 1240 series AP
  • Featureset: k9w7: autonomous IOS
  • Version: 124-25d.JA1: 12.4(25d)JA1


As AP IOS is always distributed as a tar file, the AP cannot directly execute such a file (thus, if you were to copy c1240-k9w7-tar.124-25d.JA1.tar directly onto AP flash, and then try to boot it, this could not work.)  The tar file contains, in addition to the IOS image proper, the radio firmware files, the HTML GUI files (if present), and various other files.  The AP IOS tar file must be unbundled into AP flash using the archive exec command (this is done in an automated fashion when a lightweight AP is upgraded after joining a WLC.)  After unbundling, the IOS image itself be in a file called flash:/platform-featureset-mx.version/platform-featureset-mx.version - for example, flash:/c1240-k9w7-mx.124-25d.JA1/c1240-k9w7-mx.124-25d.JA1.  The AP is configured to boot this image if the bootloader BOOT environmental variable is set accordingly.


Autonomous: Multiple SSID With Multiple VLANs configuration example on Cisco Aironet APs 

Cisco's Wireless TAC teams is one of the best around. Their group is small when compared to other groups like r/s and security. Ive had the pleasure to work with most if not all of them over the years by simply opening a TAC case and shooting the breeze. In most cases when I open a ticket the guys know me by name. Hey if you pay for TAC use it !

This video is by Surendra. Surendra is not only a bad ass Cisco TAC enigneer but he also leads the pack on Cisco Wireless Support forum. He is by far one of the most active Cisco Wireless TAC engineer contributors who gives back to the community.

In this video Surendra shows how to configure multiple SSIDs with multiple VLANs.