The place I go announce tidbits and thought about wireless networks in general. Primarily about 802.11 technologies but the occasional something else slips in...
Saturday, March 19, 2011
Hands on with the Metageek Wi-Spy DBx
Sunday, February 27, 2011
Who said 5GHz was 'clean'? :)
Those of you that are familiar with Spectrum Analysis in general usually expect to see something this bad (high duty cycle) in the 2.4GHz spectrum but not the mid-5GHz spectrum! Having just reloaded my laptop with Windows 7 and installed Service Pack 1, I was in the 'let's test it all' mode to make sure nothing unexpected happens. At this point, I was pretty blindsided by the obnoxious noise happening and the 'Generic - Fixed Frequency' tag wasn't helping me any. At a loss for what this could be since I live an acre away from my nearest neighbor and several miles from the nearest airport, I pinged a few of my friends. They suggested the usual suspects - MRI machine, TDWR, neighbors, etc all of which I explained away by location. Being that TDWR is in the 5470-5725 frequency, I changed my card over to 5.725 - 5.850 and after some time got this equally disturbing read:
At this point, I started to suspect my Spectrum Analyzer since I was using a non-Cisco branded Spectrum Analyzer card with the Cisco Spectrum Expert software (the card I was using had the Cognio components that Cisco purchased and re-branded as their own). So I grabbed a copy of the card manufacturers software to rule out in compatibility and I got the same results.
At the end of the day, I was able to swap in a Cisco branded SA card and my results normalized. Clearly I have a flakey (old) SA card that was giving me improper readings. Lessons learned:
- Always test your tools and keep them in good working order
- Don't assume that your tools are telling you the truth. If you see something suspect, dig into it and validate against another source
New survey rig!
The intermediary piece attached to the factory mount bracket is the brush head that I picked up from The Home Depot in their drywall finishing section:
Home Depot - Drywall Stippling Brush
After ripping out the bristles, a choice few holes later and my mount was ready! Next to place the battery and AP + mount in the bottom of the Pelican case and outline the pick-and-pluck:
Here is what the bottom of the Pelican looks like with the components nestled in - I coiled my CAT5 network cable around the mount and laid in the two 90 degree arms:
Add a top layer with some space for my spare laptop batteries, the AC adapter and some survey cards and call it just about done:
Now I'm off for a week of surveying!
Saturday, January 15, 2011
Surveying with a 3502 (followup post)
Sunday, December 19, 2010
Busy weeks!
http://www.mobileaccess.com/products-services/p/category/mobileaccessve
After that, spent a few days in San Jose for the Cisco Partner VT meetings and learned about all sorts of up coming new stuff from Cisco that can't be talked about yet - infact, that's probably the biggest reason that I've been somewhat quiet recently - being wrapped up in NDA style information makes it hard to be social. :)
Contribution to the https://www.myciscocommunity.com/ page netted me a Cisco Cius when they're available. Thanks to Vic Nunes for making that happen!
Upcoming in March (17th and 18th) is the Wireless Tech Field day in San Jose that I'm quite excited to be a part of! The fine folks over at Gestalt IT that put on the 'regular' Tech Field day have teamed up to host one specifically focused on wireless technologies. I was selected as a delegate and look very forward to my first Field Day. I think the list of presenters is being firmed up but I'm glad to hear about the ones that are lined up! Details on the event are at:
http://gestaltit.com/field-day/2011-wireless/
Looking forward to meeting Stephen Foskett and hanging with wireless powerhouses like @jenniferlucille and @MarcusBurton among all of the other delegates that have confirmed.
3502 surveying
Monday, October 25, 2010
New H-REAP 'feature' in WLC 7.0 code
When a Hybrid REAP access point enters into a standalone mode, the following occurs:
•The access point checks whether it is able to reach the default gateway via ARP. If so, it will continue to try and reach the controller.
If the access point fails to establish the ARP, the following will occur.
•The access point attempts to discover for five times and if it still cannot find the controller, it tries to renew the DHCP on the ethernet interface to get a new DHCP IP.
•The access point will retry for five times, and if that fails, the access point will renew the IP address of the interface again, this will happen for three attempts.
•If the three attemps fail, the access point will fall back to the static IP and will reboot (only if the access point is configured with a static IP).
•Reboot is done to remove the possibility of any unknown error the access point configuration.
Once the access point reestablishes a connection with the controller, it disassociates all clients, applies new configuration information from the controller, and reallows client connectivity.




